SCSI Commands Reference Manual Seagate 2014year

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SCSI Commands Reference Manual

Parallel SCSI
Fibre Channel (FC)
Serial Attached SCSI (SAS)

100293068
Rev. H
July 2014

© 2014 Seagate Technology LLC. All rights reserved.
Publication number: 100293068, Rev. H July 2014
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CONTENTS
1.0

Definitions, Symbols, Abbreviations, Keywords, And Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
1.1
Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
1.2
Symbols and abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
1.3
Keywords . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
1.4
Conventions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11

2.0

General Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
2.1
Command Descriptor Block (CDB) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
2.1.1
CDB usage and structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
2.1.2
The fixed length CDB formats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
2.1.3
The variable length CDB formats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
2.2
Common CDB fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
2.2.1
Operation Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
2.2.2
SERVICE ACTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
2.2.3
Logical block address. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
2.2.4
TRANSFER LENGTH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
2.2.5
PARAMETER LIST LENGTH. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
2.2.6
ALLOCATION LENGTH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
2.2.7
CONTROL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
2.2.8
Grouping function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
2.3
Parameter Rounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
2.4
Sense data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
2.4.1
Sense data introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19

3.0

Command Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
3.1
CHANGE DEFINITION command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
3.2
COMPARE command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
3.3
COPY command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
3.4
COPY AND VERIFY command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
3.5
FORMAT UNIT command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
3.5.1
FORMAT UNIT command overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
3.5.2
FORMAT UNIT parameter list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
3.5.3
Parameter list header . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44
3.5.4
Initialization pattern descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
3.5.5
Address descriptor formats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
3.6
INQUIRY command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
3.6.1
INQUIRY command introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
3.6.2
Standard INQUIRY data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55
3.6.3
SCSI Parallel Interface specific INQUIRY data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61
3.6.4
Vital product data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62
3.7
LOG SELECT command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63
3.7.1
Processing LOG SELECT when the parameter list length is zero . . . . . . . . . . . . . . . . . . . . .64
3.8
LOG SENSE command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67
3.9
MODE SELECT(6) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68
3.10
MODE SELECT (10) command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70
3.11
MODE SENSE(6) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70
3.11.1
MODE SENSE(6) command introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70
3.12
MODE SENSE(10) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72
3.13
PERSISTENT RESERVE IN command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73
3.13.1
PERSISTENT RESERVE IN command introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73
3.13.2
READ KEYS service action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74
3.13.3
READ RESERVATION service action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74
3.13.4
REPORT CAPABILITIES service action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78
3.13.5
READ FULL STATUS service action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .81
3.14
PERSISTENT RESERVE OUT command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83

SCSI COMMANDS REFERENCE MANUAL, REV. H

III

CONTENTS
3.14.1
3.14.2
3.14.3
3.14.4
3.15
3.16
3.17
3.18
3.19
3.20
3.21
3.22

3.23
3.24
3.25
3.26
3.27
3.28
3.29
3.30
3.31
3.32

3.33
3.34
3.35

3.36
3.37
3.38
3.39
3.40

3.41

PERSISTENT RESERVE OUT command introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83
PERSISTENT RESERVE OUT service actions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83
Basic PERSISTENT RESERVE OUT parameter list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85
Parameter list for the PERSISTENT RESERVE OUT
command with REGISTER AND MOVE service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88
PRE-FETCH (10) command, PRE-FETCH (16) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89
PREVENT ALLOW MEDIUM REMOVAL command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89
READ (6) command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89
READ (10) command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91
READ (12) command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95
READ (16) command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95
READ (32) command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96
READ BUFFER command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97
3.22.1
READ BUFFER command introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97
3.22.2
Combined header and data mode (00h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98
3.22.3
Vendor specific mode (01h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98
READ CAPACITY (10) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104
3.23.1
READ CAPACITY (10) overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104
3.23.2
READ CAPACITY (10) parameter data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105
READ CAPACITY (16) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106
3.24.1
READ CAPACITY (16) command overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106
3.24.2
READ CAPACITY (16) parameter data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .107
READ DEFECT DATA (10) command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .109
3.25.1
READ DEFECT DATA (10) command overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .109
3.25.2
READ DEFECT DATA (10) parameter data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .110
READ DEFECT DATA (12) command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111
3.26.1
READ DEFECT DATA (12) command overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111
3.26.2
READ DEFECT DATA (12) parameter data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .112
READ LONG (10) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .113
READ LONG (16) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114
REASSIGN BLOCKS command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .115
3.29.1
REASSIGN BLOCKS command overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .115
3.29.2
REASSIGN BLOCKS parameter list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .115
RECEIVE DIAGNOSTIC RESULTS command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .117
RELEASE(6) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119
RELEASE (10) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119
3.32.1
RELEASE(10) command introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119
3.32.2
Logical unit release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .120
3.32.3
Third-party release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .120
REPORT IDENTIFYING INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .121
3.33.1
IDENTIFYING INFORMATION SUPPORTED parameter data . . . . . . . . . . . . . . . . . . . . . .122
REPORT LUNS command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123
REPORT SUPPORTED OPERATION CODES command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .125
3.35.1
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .125
3.35.2
All-commands parameter data format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .127
3.35.3
One_command parameter data format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128
3.35.4
Command timeouts descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .130
REPORT SUPPORTED TASK MANAGEMENT FUNCTIONS commands. . . . . . . . . . . . . . . . . . . . .132
REPORT TIMESTAMP command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .135
REQUEST SENSE command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136
RESERVE(6) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .137
RESERVE (10) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138
3.40.1
RESERVE (10) command introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138
3.40.2
Logical unit reservation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138
3.40.3
Third-party reservation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .139
3.40.4
Superseding reservations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .139
REZERO UNIT command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .140

SCSI COMMANDS REFERENCE MANUAL, REV. H

IV

CONTENTS
3.42

3.43
3.44
3.45
3.46
3.47
3.48
3.49
3.50
3.51
3.52
3.53
3.54
3.55
3.56
3.57
3.58
3.59
3.60
3.61
3.62
3.63
3.64
3.65
3.66
3.67
3.68

3.69
3.70
3.71
3.72

SANITIZE command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .141
3.42.1
SANITIZE command introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .141
3.42.2
SANITIZE service actions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .142
3.42.3
SANITIZE command with OVERWRITE service action . . . . . . . . . . . . . . . . . . . . . . . . . . . .142
3.42.4
SANITIZE command with BLOCK ERASE service action . . . . . . . . . . . . . . . . . . . . . . . . . .143
3.42.5
SANITIZE command with CRYPTOGRAPHIC ERASE service action . . . . . . . . . . . . . . . .144
3.42.6
SANITIZE command with EXIT FAILURE MODE service action . . . . . . . . . . . . . . . . . . . . .144
SECURITY PROTOCOL IN command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .144
3.43.1
Command description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .144
3.43.2
Security protocol information description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .146
SECURITY PROTOCOL OUT command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .152
SEEK command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .153
SEEK EXTENDED command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .154
SEND DIAGNOSTIC command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .155
SET IDENTIFYING INFORMATION command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .157
SET TIMESTAMP command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .159
START STOP UNIT command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .160
SYNCHRONIZE CACHE (10) command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .162
SYNCHRONIZE CACHE (16) command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .164
TEST UNIT READY command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .165
UNMAP command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .166
3.54.1
UNMAP command overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .166
3.54.2
UNMAP parameter list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .167
VERIFY (10) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .169
VERIFY (12) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .177
VERIFY (16) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .177
VERIFY (32) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .177
WRITE (6) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .179
WRITE (10) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .180
WRITE (12) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .184
WRITE (16) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .184
WRITE (32) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .185
WRITE AND VERIFY (10) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .186
WRITE AND VERIFY (12) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .187
WRITE AND VERIFY (16) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .187
WRITE AND VERIFY (32) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .188
WRITE BUFFER command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .189
3.68.1
WRITE BUFFER command introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .189
3.68.2
Combined header and data mode (00h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .190
3.68.3
Vendor specific mode (01h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191
3.68.4
Data mode (02h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191
3.68.5
Download microcode and activate mode (04h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191
3.68.6
Download microcode, save, and activate mode (05h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191
3.68.7
Download microcode with offsets and activate mode (06h) . . . . . . . . . . . . . . . . . . . . . . . . .191
3.68.8
Download microcode with offsets and save mode (07h) . . . . . . . . . . . . . . . . . . . . . . . . . . .192
3.68.9
Write data to echo buffer mode (0Ah) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .192
3.68.10 Download microcode with offsets, select activation events, save,
...
and defer activate mode (0Dh). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .192
3.68.11 Download microcode with offsets, save, and defer activate mode (0Eh). . . . . . . . . . . . . . .193
3.68.12 Activate deferred microcode mode (0Fh) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .193
3.68.13 Enable expander communications protocol and Echo buffer mode (1Ah) . . . . . . . . . . . . . .193
3.68.14 Disable expander communications protocol mode (1Bh). . . . . . . . . . . . . . . . . . . . . . . . . . .193
3.68.15 Download application log mode (1Ch) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .194
WRITE LONG (10) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .196
WRITE LONG (16) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .198
WRITE SAME (10) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .199
WRITE SAME (16) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .201

SCSI COMMANDS REFERENCE MANUAL, REV. H

V

CONTENTS
3.73
4.0

WRITE SAME (32) command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .202

Parameters for all device types. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .203
4.1
Diagnostic parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .203
4.1.1
Diagnostic page format and page codes for all device types . . . . . . . . . . . . . . . . . . . . . . . .203
4.1.2
Supported diagnostic pages (00h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .205
4.1.3
Translate Address input page (40h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .206
4.1.4
Translate Address Output diagnostic page (40h). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .208
4.1.5
SCSI Enclosure Services pages (01h - 2Fh) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .209
4.1.6
Rebuild Assist Input diagnostic page . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .210
4.1.7
Rebuild Assist Output diagnostic page . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .211
4.2
Log parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .212
4.2.1
Summary of log page codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .212
4.2.2
Log page structure and page codes for all device types . . . . . . . . . . . . . . . . . . . . . . . . . . .213
4.2.3
Application Client log page (0Fh) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .220
4.2.4
Background Scan log page (15h). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .222
4.2.5
Cache Statistics page (37h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .226
4.2.6
Error counter log pages (WRITE, READ, and VERIFY, 02h, 03h, and 05h) . . . . . . . . . . . .227
4.2.7
Factory Log page (3Eh) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .229
4.2.8
Informational Exceptions log page (2Fh) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230
4.2.9
Non-Medium Error log page (06h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .232
4.2.10
Power Condition Transitions log page (1Ah) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .233
4.2.11
Protocol-Specific Port log page (18h). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .235
4.2.12
Self-Test Results log page (10h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .241
4.2.13
Solid State Media log page (11h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .243
4.2.14
Start-Stop Cycle Counter log page (0Eh). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .245
4.2.15
Supported Log Pages log page (00h/ 00h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .247
4.2.16
Supported Log Pages and Subpages log page . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .248
4.2.17
Temperature log page (0Dh) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .249
4.3
Mode parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .251
4.3.1
Mode parameters overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .251
4.3.2
Mode parameter list format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .252
4.3.3
Mode parameter header formats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .252
4.3.4
Mode parameter block descriptors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253
4.3.5
Mode page and subpage formats and page codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .256
4.3.6
Application Tag mode page (0Ah/ 02h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .257
4.3.7
Background Control mode page (1Ch/ 01h). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .259
4.3.8
Caching Mode page (08h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .261
4.3.9
Control mode page (0Ah) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .264
4.3.10
Control Extension mode page (0Ah/ 01h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .269
4.3.11
Disconnect-Reconnect mode page (02h). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .270
4.3.12
Format Parameters page (03h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .277
4.3.13
Informational Exceptions Control mode page (1Ch) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .279
4.3.14
Power Condition mode page (1Ah) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .282
4.3.15
Power Consumption Mode page (1Ah/ 01h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .285
4.3.16
Read-Write Error Recovery mode page (01h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .286
4.3.17
Protocol Specific Logical Unit mode page (18h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .290
4.3.18
Protocol Specific Port mode page (19h). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .294
4.3.19
Rigid Drive Geometry Parameters page (04h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .328
4.3.20
Seagate Specific Unit Attention parameters page (00h) . . . . . . . . . . . . . . . . . . . . . . . . . . .330
4.3.21
Verify Error Recovery mode page (07h). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .332
4.4
Vital product data parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .333
4.4.1
Vital product data parameters overview and page codes . . . . . . . . . . . . . . . . . . . . . . . . . .333
4.4.2
ASCII Information VPD page (01h - 7Fh). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .334
4.4.3
Block Device Characteristics VPD page (B1h). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .335
4.4.4
Block Limits VPD page (B0h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .337
4.4.5
Date Code page (C1h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .340

SCSI COMMANDS REFERENCE MANUAL, REV. H

VI

CONTENTS
4.4.6
4.4.7
4.4.8
4.4.9
4.4.10
4.4.11
4.4.12
4.4.13
4.4.14
4.4.15
4.4.16
4.4.17

Device Behavior page (C3h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .341
Extended INQUIRY Data VPD page (86h). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .342
Firmware Numbers page (C0h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .346
Device Identification VPD page (83h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .348
Jumper Settings page (C2h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .351
Logical Block Provisioning VPD page . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .353
Mode Page Policy VPD page (87h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .355
Power Conditions Vital Product Data page (8Ah) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .357
Power Consumption Vital Product Data page . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .359
SCSI Ports VPD page . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .360
Supported Vital Product Data pages (00h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .363
Unit Serial Number page (80h). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .364

SCSI COMMANDS REFERENCE MANUAL, REV. H

VII

TABLES
Table 1.
Table 2.
Table 3.
Table 4.
Table 5.
Table 6.
Table 7.
Table 8.
Table 9.
Table 10.
Table 11.
Table 12.
Table 13.
Table 14.
Table 15.
Table 16.
Table 17.
Table 18.
Table 19.
Table 20.
Table 21.
Table 22.
Table 23.
Table 24.
Table 25.
Table 26.
Table 27.
Table 28.
Table 29.
Table 30.
Table 31.
Table 32.
Table 33.
Table 34.
Table 35.
Table 36.
Table 37.
Table 38.
Table 39.
Table 40.
Table 41.
Table 42.
Table 43.
Table 44.
Table 45.
Table 46.
Table 47.
Table 48.

ISO v American Numbering Conventions .......................................................................................................11
Typical CDB for 6-byte commands .................................................................................................................12
Typical CDB for 12-byte commands ...............................................................................................................13
Typical CDB for long LBA 16-byte commands ................................................................................................13
Typical CDB for 10-byte commands ...............................................................................................................13
Typical variable length CDB ............................................................................................................................14
Typical variable length CDB for long LBA 32-byte commands .......................................................................15
OPERATION CODE byte ................................................................................................................................16
Group Code values .........................................................................................................................................16
Control Byte ....................................................................................................................................................17
Sense data response codes ...........................................................................................................................19
Descriptor format sense data ..........................................................................................................................19
Sense data descriptor format ..........................................................................................................................20
Sense data descriptor types ...........................................................................................................................21
Information sense data descriptor format .......................................................................................................21
Command-specific information sense data descriptor format .........................................................................22
Sense key specific sense data descriptor format ............................................................................................22
Sense key specific field definitions .................................................................................................................23
Field pointer sense key specific data ..............................................................................................................23
Actual retry count sense key specific data ......................................................................................................24
Progress indication sense key specific data ...................................................................................................24
Segment pointer sense key specific data .......................................................................................................25
Unit attention condition queue overflow sense key specific data ....................................................................25
Field replaceable unit sense data descriptor format .......................................................................................26
Progress indications sense data descriptor format .........................................................................................26
Vendor specific sense data descriptor format .................................................................................................27
Fixed format sense data .................................................................................................................................27
Sense key descriptions ...................................................................................................................................30
Additional Sense and Additional Sense Qualifier codes .................................................................................31
CHANGE DEFINITION command ..................................................................................................................39
Definition parameter field ................................................................................................................................39
FORMAT UNIT command ...............................................................................................................................40
FORMAT UNIT command address descriptor usage .....................................................................................42
FORMAT UNIT parameter list .........................................................................................................................43
Short parameter list header ............................................................................................................................44
Long parameter list header .............................................................................................................................44
FMTPINFO field and PROTECTION FIELDS USAGE field ............................................................................45
Initialization pattern descriptor ........................................................................................................................47
Initialization pattern modifier (IP MODIFIER) field ..........................................................................................47
initialization pattern type field ..........................................................................................................................48
Address descriptor formats .............................................................................................................................49
Short block format address descriptor (000b) .................................................................................................49
Bytes from index format address descriptor (100b) ........................................................................................50
Bytes from index format address descriptor (100b) ........................................................................................51
Long block format address descriptor (011b) .................................................................................................52
Bytes from index format address descriptor (100b) ........................................................................................52
Physical sector format address descriptor (101b) ...........................................................................................53
INQUIRY command ........................................................................................................................................54

SCSI COMMANDS REFERENCE MANUAL, REV. H

VIII

TABLES
Table 49.
Table 50.
Table 51.
Table 52.
Table 53.
Table 54.
Table 55.
Table 56.
Table 57.
Table 58.
Table 59.
Table 60.
Table 61.
Table 62.
Table 63.
Table 64.
Table 65.
Table 66.
Table 67.
Table 68.
Table 69.
Table 70.
Table 71.
Table 72.
Table 73.
Table 74.
Table 75.
Table 76.
Table 77.
Table 78.
Table 79.
Table 80.
Table 81.
Table 82.
Table 83.
Table 84.
Table 85.
Table 86.
Table 87.
Table 88.
Table 89.
Table 90.
Table 91.
Table 92.
Table 93.
Table 94.
Table 95.
Table 96.

Standard INQUIRY data format ......................................................................................................................55
PERIPHERAL QUALIFIER .............................................................................................................................56
PERIPHERAL DEVICE TYPE ........................................................................................................................57
VERSION field codes ......................................................................................................................................58
Target Port Group Support codes ...................................................................................................................59
BQue and CmdQue bit combinations .............................................................................................................60
SPI-specific standard INQUIRY bits ...............................................................................................................61
ADDR and WBUS bit relationships .................................................................................................................61
CLOCKING codes ...........................................................................................................................................62
LOG SELECT command .................................................................................................................................63
Page Control (PC) field values ........................................................................................................................63
PAGE CODE field and SUBPAGE CODE field ...............................................................................................64
PCR bit, SP bit, and PC field meanings when parameter list length is zero ...................................................65
LOG SENSE command ..................................................................................................................................67
MODE SELECT(6) command .........................................................................................................................68
Mode page policies .........................................................................................................................................68
MODE SELECT(10) command .......................................................................................................................70
MODE SENSE(6) command ...........................................................................................................................70
Page control (PC) field ....................................................................................................................................71
MODE SENSE(10) command .........................................................................................................................72
PERSISTENT RESERVE IN command ..........................................................................................................73
PERSISTENT RESERVE IN service action codes .........................................................................................73
PERSISTENT RESERVE IN parameter data for READ KEYS ......................................................................74
PERSISTENT RESERVE IN data for READ RESERVATION with no reservation held .................................75
PERSISTENT RESERVE IN parameter data for READ RESERVATION with reservation ............................75
Persistent reservation scope codes ................................................................................................................76
Persistent reservation type codes ...................................................................................................................77
PERSISTENT RESERVE IN parameter data for REPORT CAPABILITIES ...................................................78
ALLOW COMMANDS field .............................................................................................................................79
Persistent Reservation Type Mask format ......................................................................................................80
PERSISTENT RESERVE IN parameter data for READ FULL STATUS ........................................................81
PERSISTENT RESERVE IN full status descriptor format ..............................................................................81
PERSISTENT RESERVE OUT command ......................................................................................................83
PERSISTENT RESERVE OUT service action codes .....................................................................................84
PERSISTENT RESERVE OUT parameter list ................................................................................................85
PERSISTENT RESERVE OUT specify initiator ports additional parameter data ...........................................86
PERSISTENT RESERVE OUT service actions and valid parameters (part 1 of 2) ........................................87
PERSISTENT RESERVE OUT service actions and valid parameters (part 2 of 2) ........................................87
PERSISTENT RESERVE OUT command with REGISTER AND MOVE service ...........................................88
READ (6) command ........................................................................................................................................89
Protection information checking for READ (6) ................................................................................................90
READ (10) command ......................................................................................................................................91
RDPROTECT field ..........................................................................................................................................91
Force unit access for read operations .............................................................................................................94
READ (12) command ......................................................................................................................................95
READ (16) command ......................................................................................................................................95
READ (32) command ......................................................................................................................................96
READ BUFFER command ..............................................................................................................................97

SCSI COMMANDS REFERENCE MANUAL, REV. H

IX

TABLES
Table 97. MODE field ......................................................................................................................................................97
Table 98. READ BUFFER header ..................................................................................................................................98
Table 99. READ BUFFER descriptor ..............................................................................................................................98
Table 100. Buffer offset boundary .....................................................................................................................................99
Table 101. Echo buffer descriptor .....................................................................................................................................99
Table 102. Error history BUFFER ID field .......................................................................................................................100
Table 103. Summary of error history directory device server actions .............................................................................101
Table 104. Error history directory ....................................................................................................................................101
Table 105. EHS_RETRIEVED field ................................................................................................................................102
Table 106. EHS_SOURCE field ......................................................................................................................................102
Table 107. Error history directory entry ...........................................................................................................................102
Table 108. READ CAPACITY (10) command .................................................................................................................104
Table 109. READ CAPACITY (10) parameter data ........................................................................................................105
Table 110. READ CAPACITY (16) command .................................................................................................................106
Table 111. READ CAPACITY (16) parameter data ........................................................................................................107
Table 112. P_TYPE FIELD and PROT_EN bit ...............................................................................................................107
Table 113. LOGICAL BLOCKS PER PHYSICAL BLOCKS EXPONENT field ................................................................108
Table 114. READ DEFECT DATA (10) command ..........................................................................................................109
Table 115. READ DEFECT DATA (10) parameter data .................................................................................................110
Table 116. READ DEFECT DATA (12) command ..........................................................................................................111
Table 117. READ DEFECT DATA (12) parameter data .................................................................................................112
Table 118. READ LONG (10) command .........................................................................................................................113
Table 119. READ LONG (16) command .........................................................................................................................114
Table 120. REASSIGN BLOCKS command ...................................................................................................................115
Table 121. REASSIGN BLOCKS parameter list .............................................................................................................115
Table 122. REASSIGN BLOCKS short parameter list header ........................................................................................116
Table 123. REASSIGN BLOCKS long parameter list header .........................................................................................116
Table 124. RECEIVE DIAGNOSTIC RESULTS command ............................................................................................117
Table 125. Diagnostic Data Bytes ...................................................................................................................................118
Table 126. RELEASE(6) Command ...............................................................................................................................119
Table 127. RELEASE (10) Command ............................................................................................................................119
Table 128. RELEASE(10) parameter list ........................................................................................................................120
Table 129. REPORT IDENTIFYING INFORMATION command ...................................................................................121
Table 130. INFORMATION TYPE ..................................................................................................................................121
Table 131. REPORT IDENTIFYING INFORMATION parameter data ............................................................................122
Table 132. REPORT IDENTIFYING INFORMATION SUPPORTED parameter data ....................................................122
Table 133. Identifying Information descriptor ..................................................................................................................123
Table 134. REPORT LUNS command ............................................................................................................................123
Table 135. SELECT REPORT field ................................................................................................................................124
Table 136. REPORT LUNS parameter data format ........................................................................................................124
Table 137. REPORT SUPPORTED OPERATION CODES command ...........................................................................125
Table 138. REPORTING OPTIONS field ........................................................................................................................126
Table 139. All_commands parameter data .....................................................................................................................127
Table 140. Command descriptor format .........................................................................................................................127
Table 141. One_command parameter data ....................................................................................................................128
Table 142. SUPPORT values .........................................................................................................................................129
Table 143. Command timeouts descriptor format ...........................................................................................................130
Table 144. Command timeout descriptor COMMAND SPECIFIC field usage in this manual .........................................130
SCSI COMMANDS REFERENCE MANUAL, REV. H

X

TABLES
Table 145. REPORT SUPPORTED TASK MANAGEMENT FUNCTIONS command ....................................................132
Table 146. REPORT SUPPORTED TASK MANAGEMENT FUNCTIONS parameter data ...........................................132
Table 147. REPORT SUPPORTED TASK MANAGEMENT FUNCTIONS extended parameter data ...........................133
Table 148. REPORT TIMESTAMP command ................................................................................................................135
Table 149. REPORT TIMESTAMP parameter data format ............................................................................................136
Table 150. REQUEST SENSE command .......................................................................................................................136
Table 151. RESERVE(6) command ................................................................................................................................137
Table 152. RESERVE (10) Command ............................................................................................................................138
Table 153. RESERVE(10) ID only parameter list ...........................................................................................................139
Table 154. REZERO UNIT command (01h) ...................................................................................................................140
Table 155. SANITIZE command (48h) ............................................................................................................................141
Table 156. SANITIZE service action codes ....................................................................................................................142
Table 157. OVERWRITE service action parameter list ..................................................................................................142
Table 158. TEST field .....................................................................................................................................................143
Table 159. SECURITY PROTOCOL IN command .........................................................................................................144
Table 160. SECURITY PROTOCOL field in SECURITY PROTOCOL IN command ......................................................145
Table 161. SECURITY PROTOCOL SPECIFIC field for SECURITY PROTOCOL IN protocol 00h ...............................146
Table 162. Supported security protocols SECURITY PROTOCOL IN parameter data ..................................................147
Table 163. Certificate data SECURITY PROTOCOL IN parameter data .......................................................................148
Table 164. Certificate data SECURITY PROTOCOL IN parameter data .......................................................................149
Table 165. Compliance descriptor format .......................................................................................................................150
Table 166. INFORMATION TYPE ..................................................................................................................................150
Table 167. FIPS 140 Compliance descriptor ..................................................................................................................151
Table 168. REVISION field .............................................................................................................................................151
Table 169. SECURITY PROTOCOL OUT command .....................................................................................................152
Table 170. SECURITY PROTOCOL field in SECURITY PROTOCOL OUT command ..................................................152
Table 171. SEEK command (0Bh) ..................................................................................................................................153
Table 172. SEEK command (2Bh) ..................................................................................................................................154
Table 173. SEND DIAGNOSTIC command ....................................................................................................................155
Table 174. SELF-TEST CODE field ................................................................................................................................155
Table 175. SET IDENTIFYING INFORMATION command ............................................................................................157
Table 176. INFORMATION TYPE code list ....................................................................................................................158
Table 177. SET IDENTIFYING INFORMATION parameter list ......................................................................................158
Table 178. SET TIMESTAMP command ........................................................................................................................159
Table 179. SET TIMESTAMP parameter data format ....................................................................................................159
Table 180. START STOP UNIT command .....................................................................................................................160
Table 181. POWER CONDITION field and POWER CONDITION MODIFIER field .......................................................160
Table 182. SYNCHRONIZE CACHE (10) command ......................................................................................................162
Table 183. SYNC_NV bit ................................................................................................................................................162
Table 184. SYNC_ PROG field description ....................................................................................................................163
Table 185. SYNCHRONIZE CACHE (16) command ......................................................................................................164
Table 186. TEST UNIT READY command .....................................................................................................................165
Table 187. Preferred TEST UNIT READY responses ....................................................................................................165
Table 188. UNMAP command ........................................................................................................................................166
Table 189. UNMAP parameter list ..................................................................................................................................167
Table 190. UNMAP block descriptor ...............................................................................................................................168
Table 191. VERIFY (10) command .................................................................................................................................169
Table 192. VRPROTECT field with BYTCHK set to zero - medium ...............................................................................170
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XI

TABLES
Table 193. VRPROTECT field with BYTCHK set to one - medium ................................................................................172
Table 194. VRPROTECT field with BYTCHK set to one - data-out buffer ......................................................................173
Table 195. VRPROTECT field with BYTCHK set to one - byte-by-byte comparison requirements ................................175
Table 196. VERIFY (12) command .................................................................................................................................177
Table 197. VERIFY (16) command .................................................................................................................................177
Table 198. VERIFY (32) command .................................................................................................................................178
Table 199. WRITE (6) command ....................................................................................................................................179
Table 200. WRITE (10) command ..................................................................................................................................180
Table 201. WRPROTECT field .......................................................................................................................................181
Table 202. Force unit access for write operations ..........................................................................................................183
Table 203. WRITE (12) command ..................................................................................................................................184
Table 204. WRITE (16) command ..................................................................................................................................184
Table 205. WRITE (32) command ..................................................................................................................................185
Table 206. WRITE AND VERIFY (10) command ............................................................................................................186
Table 207. WRITE AND VERIFY (12) command ............................................................................................................187
Table 208. WRITE AND VERIFY (16) command ............................................................................................................187
Table 209. WRITE AND VERIFY (32) command ............................................................................................................188
Table 210. WRITE BUFFER command ..........................................................................................................................189
Table 211. WRITE BUFFER MODE field ........................................................................................................................190
Table 212. MODE SPECIFIC field ..................................................................................................................................192
Table 213. Application log data WRITE BUFFER format ...............................................................................................194
Table 214. ERROR TYPE field .......................................................................................................................................195
Table 215. CODE SET field ............................................................................................................................................195
Table 216. ERROR LOCATION FORMAT field ..............................................................................................................196
Table 217. WRITE LONG (10) command .......................................................................................................................196
Table 218. COR_DIS bit, WR_UNCOR bit and PBLOCK bit ..........................................................................................197
Table 219. WRITE LONG (16) command .......................................................................................................................198
Table 220. WRITE SAME (10) command .......................................................................................................................199
Table 221. ANCHOR bit, UNMAP bit, and ANC_SUP bit relationships ..........................................................................199
Table 222. LBDATA bit and PBDATA bit ........................................................................................................................200
Table 223. WRITE SAME (16) command .......................................................................................................................201
Table 224. WRITE SAME (32) command .......................................................................................................................202
Table 225. Diagnostic page format .................................................................................................................................203
Table 226. Diagnostic page codes ..................................................................................................................................204
Table 227. Supported diagnostic pages .........................................................................................................................205
Table 228. Translate Address page—input diagnostic page (40h) .................................................................................206
Table 229. Address Field for Short Logical Block Address Format ................................................................................207
Table 230. Address Field for Physical Sector Address Format ......................................................................................207
Table 231. Translate Address Output diagnostic page ...................................................................................................208
Table 232. SCSI Enclosure Services page .....................................................................................................................209
Table 233. Rebuild Assist Input diagnostic page ............................................................................................................210
Table 234. Rebuild Assist Output diagnostic page .........................................................................................................211
Table 235. Log page codes ............................................................................................................................................212
Table 236. Log page format ............................................................................................................................................213
Table 237. LOG SELECT PCR bit, SP bit, and DS bit meanings when parameter list length is not zero ......................214
Table 238. Log parameter ...............................................................................................................................................215
Table 239. Threshold met criteria (TMC) field ................................................................................................................216
Table 240. FORMAT AND LINKING field .......................................................................................................................217
SCSI COMMANDS REFERENCE MANUAL, REV. H

XII

TABLES
Table 241. Parameter control byte values for bounded data counter parameters ..........................................................217
Table 242. Parameter control byte values for unbounded data counter parameters ......................................................218
Table 243. Parameter control byte values for ASCII format list log parameters .............................................................219
Table 244. Parameter control byte values for binary format list log parameters .............................................................219
Table 245. Keywords for resetting or changing log parameters .....................................................................................220
Table 246. Application Client log page parameter codes ...............................................................................................220
Table 247. Application client log page ............................................................................................................................221
Table 248. General usage application client parameter data .........................................................................................221
Table 249. Background Scan log page parameter codes ...............................................................................................222
Table 250. Background Scan log page ...........................................................................................................................222
Table 251. Background Scan Status parameter format ..................................................................................................223
Table 252. Background Scan Status field .......................................................................................................................224
Table 253. Background Medium Scan parameter format ...............................................................................................224
Table 254. REASSIGN STATUS field .............................................................................................................................225
Table 255. Parameter codes ...........................................................................................................................................226
Table 256. Cache Statistics page (37h) ..........................................................................................................................226
Table 257. Error counter log page codes ........................................................................................................................227
Table 258. Parameter codes for error counter log pages ...............................................................................................227
Table 259. Error counter log page ..................................................................................................................................228
Table 260. Factory Log page (3Eh) ................................................................................................................................229
Table 261. Informational exceptions parameter codes ...................................................................................................230
Table 262. Informational Exceptions log page ................................................................................................................230
Table 263. Informational exceptions general parameter data .........................................................................................231
Table 264. Non-medium error event parameter codes ...................................................................................................232
Table 265. Non-Medium Error log page ..........................................................................................................................232
Table 266. Non-Medium Error Count log parameter .......................................................................................................233
Table 267. Power Condition Transitions log page parameter codes ..............................................................................233
Table 268. Power Condition Transitions log page ..........................................................................................................234
Table 269. Power Condition Transitions log parameter format .......................................................................................234
Table 270. Protocol-Specific Port log page for SAS SSP ...............................................................................................235
Table 271. Protocol-Specific Port log parameter for SAS ...............................................................................................235
Table 272. SAS phy log descriptor .................................................................................................................................236
Table 273. Device type field ............................................................................................................................................237
Table 274. Reason field definition ...................................................................................................................................238
Table 275. NEGOTIATED LOGICAL LINK RATE field ...................................................................................................238
Table 276. Phy event descriptor .....................................................................................................................................240
Table 277. Self-Test Results log page ............................................................................................................................241
Table 278. Self-test results log parameter format ...........................................................................................................241
Table 279. SELF-TEST RESULTS field .........................................................................................................................242
Table 280. Solid State Media log parameters .................................................................................................................243
Table 281. Solid State Media log page ...........................................................................................................................243
Table 282. Percentage Used Endurance Indicator log parameter format .......................................................................244
Table 283. Solid State Media log parameters .................................................................................................................245
Table 284. Start-Stop Cycle Counter log page ...............................................................................................................245
Table 285. Supported log pages .....................................................................................................................................247
Table 286. Supported Log Pages and Subpages log page (00h/ FFh) ..........................................................................248
Table 287. Supported page/subpage descriptor .............................................................................................................248
Table 288. Temperature log page parameter codes .......................................................................................................249
SCSI COMMANDS REFERENCE MANUAL, REV. H

XIII

TABLES
Table 289. Temperature log page ...................................................................................................................................249
Table 290. Mode page codes and subpage codes .........................................................................................................251
Table 291. Mode parameter list ......................................................................................................................................252
Table 292. Mode parameter header(6) ...........................................................................................................................252
Table 293. Mode parameter header(10) .........................................................................................................................252
Table 294. Short LBA mode parameter block descriptor ................................................................................................254
Table 295. Long LBA mode parameter block descriptor .................................................................................................255
Table 296. Page_0 mode page format ...........................................................................................................................256
Table 297. SUB_PAGE mode page format ....................................................................................................................256
Table 298. Application Tag mode page ..........................................................................................................................257
Table 299. Application Tag descriptor format .................................................................................................................258
Table 300. Background Control mode page ...................................................................................................................259
Table 301. Caching Mode page (08h) ............................................................................................................................261
Table 302. Control mode page .......................................................................................................................................264
Table 303. Task set type (TST) field ...............................................................................................................................264
Table 304. QUEUE ALGORITHM MODIFIER field .........................................................................................................265
Table 305. Unit attention interlocks control (UA_INTLCK_CTRL) field ...........................................................................266
Table 306. Queue error management (QERR) field .......................................................................................................266
Table 307. AUTOLOAD MODE field ...............................................................................................................................268
Table 308. Control Extension mode page .......................................................................................................................269
Table 309. Disconnect-Reconnect mode page ...............................................................................................................270
Table 310. Data transfer disconnect control ...................................................................................................................272
Table 311. Disconnect-Reconnect mode page (02h) .....................................................................................................273
Table 312. Disconnect-Reconnect mode page for SAS .................................................................................................275
Table 313. Format Parameters page (03h) .....................................................................................................................277
Table 314. Informational Exceptions Control mode page ...............................................................................................279
Table 315. Method of reporting informational exceptions (MRIE) field ...........................................................................281
Table 316. Power Condition mode page .........................................................................................................................282
Table 317. PM_BG_PRECEDENCE field .......................................................................................................................283
Table 318. CCF_IDLE field .............................................................................................................................................284
Table 319. CCF_STANDBY field ....................................................................................................................................284
Table 320. CCF_STOPPED field ....................................................................................................................................285
Table 321. Power Consumption mode page ...................................................................................................................285
Table 322. Read-Write Error Recovery mode page ........................................................................................................286
Table 323. Combined error recovery bit descriptions .....................................................................................................287
Table 324. Protocol Specific Logical Unit mode page ....................................................................................................290
Table 325. PROTOCOL IDENTIFIER values .................................................................................................................291
Table 326. Fibre Channel Logical Unit Control mode page (18h) ...................................................................................292
Table 327. SAS Protocol-Specific Logical Unit mode page subpages ...........................................................................293
Table 328. Protocol-Specific Logical Unit mode page for SAS SSP - short format ........................................................293
Table 329. Page_0 format Protocol Specific Port mode page ........................................................................................294
Table 330. Sub_page format Protocol Specific Port mode page ....................................................................................294
Table 331. Port Control Mode page short format (19h) ..................................................................................................295
Table 332. Subpage Code field values ...........................................................................................................................296
Table 333. Port Control Mode page long format (19h) ...................................................................................................296
Table 334. Summary of margin control field values ........................................................................................................297
Table 335. Margin control subpage ................................................................................................................................298
Table 336. Saved training configuration values subpage ...............................................................................................299
SCSI COMMANDS REFERENCE MANUAL, REV. H

XIV

TABLES
Table 337. Negotiated settings subpage ........................................................................................................................300
Table 338. Report transfer capabilities subpage ............................................................................................................301
Table 339. Fibre Channel Interface Control page (19h) .................................................................................................302
Table 340. Values for RR_TOV UNITS ..........................................................................................................................304
Table 341. Protocol-Specific Port mode page subpages ................................................................................................305
Table 342. Protocol-Specific Port mode page for SAS SSP - short format - SAS-1.1 ....................................................306
Table 343. I_T NEXUS LOSS TIME values ....................................................................................................................307
Table 344. Protocol-Specific Port mode page for SAS SSP- short format - SAS-3 ........................................................308
Table 345. Protocol-Specific Port mode page SAS SSP - Phy Control And Discover subpage .....................................310
Table 346. SAS phy mode descriptor .............................................................................................................................311
Table 347. The HARDWARE MINIMUM & MAXIMUM PHYSICAL LINK RATE field values ..........................................313
Table 348. The PROGRAMMED MINIMUM and MAXIMUM PHYSICAL LINK RATE field values ................................313
Table 349. Port Control Mode Page ...............................................................................................................................314
Table 350. Enhanced Phy Control mode page ...............................................................................................................315
Table 351. Enhanced phy control mode descriptor ........................................................................................................316
Table 352. Transceiver Control (Out) subpage ...............................................................................................................318
Table 353. Transceiver Controls Mode descriptor (1.5Gb - 6Gb Link Rate) ...................................................................319
Table 354. Transceiver Controls descriptor (12Gb Link Rate) ........................................................................................320
Table 355. Controllable Link Rates .................................................................................................................................320
Table 356. DRIVER STRENGTH CONTROL or C1 PRE-CURSOR CONTROL (12G Mode Only) values ....................321
Table 357. DRIVER EMPHASIS CONTROL or C2 AMPLITUDE CONTROL (12G Mode Only) ....................................321
Table 358. DRIVER SLEW RATE CONTROL or C3 POST CURSOR CONTROL (12G mode only) .............................321
Table 359. Receiver Threshold Control ..........................................................................................................................322
Table 360. Receiver Equalization Gain Control field ......................................................................................................322
Table 361. RESET and IREC bit function .......................................................................................................................323
Table 362. Protocol-Specific Port - Transceiver Control (In) subpage ............................................................................324
Table 363. Transceiver Controls descriptor (1.5Gb - 6Gb Link Rate) .............................................................................325
Table 364. Transceiver Controls descriptor (1.5G, 3G, 6G and 12G) ...........................................................................326
Table 365. Controllable Link Rates field .........................................................................................................................326
Table 366. Rigid Drive Geometry Parameters page (04h) ..............................................................................................328
Table 367. Rotational Position Locking ...........................................................................................................................329
Table 368. Seagate SpecificUnit Attention parameters page (00h) ................................................................................330
Table 369. Verify Error Recovery mode page .................................................................................................................332
Table 370. Vital product data page codes ......................................................................................................................333
Table 371. ASCII Information VPD page ........................................................................................................................334
Table 372. Block Device Characteristics VPD page .......................................................................................................335
Table 373. Medium Rotation Rate field ...........................................................................................................................335
Table 374. Product Type field .........................................................................................................................................335
Table 375. WABEREQ field ............................................................................................................................................336
Table 376. WACEREQ field ............................................................................................................................................336
Table 377. Nominal Form Factor Field ...........................................................................................................................336
Table 378. Block Limits VPD page .................................................................................................................................337
Table 379. Error history BUFFER ID field .......................................................................................................................338
Table 380. ETF Log Date Code page (C1h) ...................................................................................................................340
Table 381. Device Behavior page (C3h) .........................................................................................................................341
Table 382. Extended INQUIRY Data VPD page .............................................................................................................342
Table 383. ACTIVATE MICROCODE field .....................................................................................................................343
Table 384. SPT field .......................................................................................................................................................343
SCSI COMMANDS REFERENCE MANUAL, REV. H

XV

TABLES
Table 385. Firmware Numbers page (C0h) ....................................................................................................................346
Table 386. Device Identification VPD page ....................................................................................................................348
Table 387. Identification Descriptor ................................................................................................................................349
Table 388. Code set field ................................................................................................................................................349
Table 389. PROTOCOL IDENTIFIER values .................................................................................................................349
Table 390. ASSOCIATION field ......................................................................................................................................350
Table 391. IDENTIFIER Type field .................................................................................................................................350
Table 392. Device Identification page example ..............................................................................................................351
Table 393. Jumper Settings page (C2h) .........................................................................................................................351
Table 394. Drive ID bit ....................................................................................................................................................352
Table 395. Logical Block Provisioning VPD page ...........................................................................................................353
Table 396. Provisioning Type field ..................................................................................................................................354
Table 397. Mode Page Policy VPD page ........................................................................................................................355
Table 398. Mode page policy descriptor .........................................................................................................................355
Table 399. MODE PAGE POLICY field ..........................................................................................................................356
Table 400. Power Condition VPD page ..........................................................................................................................357
Table 401. Power Consumption VPD page ....................................................................................................................359
Table 402. Power consumption descriptor format ..........................................................................................................359
Table 403. POWER CONSUMPTION UNITS field .........................................................................................................359
Table 404. SCSI Ports VPD page ...................................................................................................................................360
Table 405. SCSI port designation descriptor ..................................................................................................................361
Table 406. Relative Port Identifier field ...........................................................................................................................361
Table 407. Target port Descriptor ...................................................................................................................................362
Table 408. Supported Vital Product Data pages .............................................................................................................363
Table 409. Unit Serial Number page (80h) .....................................................................................................................364

SCSI COMMANDS REFERENCE MANUAL, REV. H

XVI

1.0

Definitions, Symbols, Abbreviations, Keywords, And Conventions

This clause contains the definitions, symbols, abbreviations, keywords and, conventions used throughout this manual. These items are
from the American National Standards Institute T10 committee standards.
Applicable Documents:
INCITS 447-2008 SCSI Architecture Model - 4 (SAM-4)
T10/2104-D SCSI Architecture Model - 5 (SAM-5) Revision 11
ANSI INCITS 408-2005 SCSI Primary Commands - 3 (SPC-3)
T10/1731-D SCSI Primary Commands - 4 (SPC-4) Revision 36
ANSI INCITS 405-2005 SCSI Block Commands - 2 (SBC-2)
T10/1799-D SCSI Block Commands - 3 (SBC-3) Revision 32
ANSI INCITS 457-2010 Serial Attached SCSI - 2 (SAS-2)
ANSI INCITS 478-2011 Serial Attached SCSI - 2 (SAS-2.1)
T10/2212-D Serial Attached SCSI - 3 (SAS-3) Revision 3
ANSI INCITS 476-2011 SAS Protocol Layer (SPL)
T10/2228-D SAS Protocol Layer - 2 (SPL-2) Revision 5
ANSI INCITS 416-2006 Fibre Channel Protocol for SCSI, - 3 (FCP-3)
ANSI INCITS 481-2011 Fibre Channel Protocol for SCSI, - 4 (FCP-4)

SCSI Commands Reference Manual, Rev. H

1

1.1

Definitions

Access control list (ACL)
The data used by a SCSI target device to configure access rights for initiator ports according to the access controls state of the SCSI
target device.
Access control list entry (ACE)
One entry in the access control list.
Access controls
An optional SCSI target device feature that restricts initiator port access to specific logical units and modifies the information about logical units in the parameter data of the INQUIRY and REPORT LUNS commands.
Access controls coordinator
The entity within a SCSI target device that coordinates the management and enforcement of access controls for all logical units within
the SCSI target device. The access controls coordinator is always addressable through the ACCESS CONTROLS well known logical
unit and LUN 0.
active power condition
When a device server is capable of responding to all of its supported commands, including media access requests, without delay.
additional sense code
A combination of the ADDITIONAL SENSE CODE and ADDITIONAL SENSE CODE QUALIFIER fields in the sense data.
Application client
An object that is the source of SCSI commands. Further definition of an application client may be found in SAM-5.
Attribute
A single unit of MAM information.
Auto contingent allegiance (ACA)
The task set condition established following the return of a CHECK CONDITION status when the NACA bit is set to one in the CONTROL byte. A detailed definition of ACA may be found in SAM-5.
Blocked task
A task that is in the blocked state. Tasks become blocked when an ACA condition occurs. The blocked state ends when the ACA condition is cleared. A detailed definition of the blocked task state may be found in SAM-5.
Byte
A sequence of eight contiguous bits considered as a unit.
Cache
See cache memory.
Cache memory
A temporary and often volatile data storage area outside the area accessible by application clients that may contain a subset of the
data stored in the non-volatile data storage area.
Check data
Information contained within a redundancy group that may allow lost or destroyed XOR-protected data to be recreated.
Command
A request describing a unit of work to be performed by a device server. A detailed definition of a command may be found in SAM-5.
Command descriptor block (CDB)
The structure used to communicate commands from an application client to a device server. A CDB may have a fixed length of up to
16 bytes or a variable length of between 12 and 260 bytes.
Command standard
A SCSI standard that defines the model, commands, and parameter data for a device type (e.g., SBC-3, SSC-3, SMC-3, MMC-5, or
SES-2).
Company_id
Synonym for OUI.
Copy manager
The device server that receives an EXTENDED COPY command and performs the operation requested.
Copy target device
The name given by the EXTENDED COPY command to a source or destination logical unit (i.e., a copy target device is a logical unit,
not a SCSI target device).
Cyclic redundancy check (CRC)
An error checking mechanism that checks data integrity by computing a polynomial algorithm based checksum.
Data defect list (DLIST)
A list of defects sent by the application client to the device server during a FORMAT UNIT command.
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Data-in buffer
The buffer specified by the application client to receive data from the device server during the processing of a command.
Data-out buffer
The buffer specified by the application client to supply data that is sent from the application client to the device server during the processing of a command.
Default protection information
Values placed into protection information fields if an application client does not specify specific protection information values.‘
Deferred error
A CHECK CONDITION status and sense data that is returned as the result of an error or exception condition that occurred during processing of a previous command for which GOOD, CONDITION MET, INTERMEDIATE, and INTERMEDIATE-CONDITION MET status
has already been returned.
Device server
An object within a logical unit that processes SCSI tasks according to the rules of task management. A detailed definition of a device
server may be found in SAM-5.
Device service request
A request, submitted by an application client, conveying a SCSI command to a device server. A detailed definition of a device service
request may be found in SAM-5.
Device service response
The response returned to an application client by a device server on completion of a SCSI command. A detailed definition of a device
service response may be found in SAM-5.
Device type
The type of peripheral device (i.e., device model) implemented by the device server and indicated by the contents of the PERIPHERAL DEVICE TYPE field in the standard INQUIRY data.
Direct-access block device
A device that is capable of containing data stored in blocks that each have a unique logical block address.
Domain
An I/O system consisting of a set of SCSI devices that interact with one another by means of a service delivery subsystem.
Element
An addressable physical component of a medium changer SCSI device that may serve as the location of a removable unit of data
storage medium. A detailed definition of an element may be found in SMC-3.
Enabled task state
The only task state in which a task may make progress towards completion. A detailed definition of the enabled task state may be
found in SAM-5.
Error correcting code (ECC)
An error checking mechanism that checks data integrity and enables some errors in the data to be corrected.
Error history I_T nexus
An I_T nexus for which the device server has reserved access to the error history
snapshot (see SPC-4).
Error history snapshot
The contents of the error history at a specific point in time (see SPC-4).
Exclusive-or (XOR)
A Boolean arithmetic function on two binary input values that results in an output value of 1 if one and only one of the input values is 1.
Extended Unique Identifier, a 48-bit globally unique identifier (EUI-48)
The IEEE maintains a tutorial describing EUI-48 at http://standards.ieee.org/regauth/oui/tutorials/EUI48.html.
Extended Unique Identifier, a 64-bit globally unique identifier (EUI-64)
The IEEE maintains a tutorial describing EUI-64 at http://standards.ieee.org/regauth/oui/tutorials/EUI64.html.
Extent
A fixed set of logical blocks occupying contiguous logical block addresses on a single logical unit.
Faulted I_T nexus
The I_T nexus on which a CHECK CONDITION status was returned that resulted in the establishment of an ACA. The faulted I_T
nexus condition is cleared when the ACA condition is cleared.
Field
A group of one or more contiguous bits, a part of a larger structure such as a CDB or sense data.

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Format corrupt
a vendor-specific condition in which the application client may not be able to perform read operations, write operations, or verify operations.
Grown defect list (GLIST)
All defects sent by the application client to the device server.
Hard reset
A condition resulting from the events defined by SAM-5 in which the SCSI device performs the hard reset operations described in
SAM-5, SPC-4, and the applicable command standards.
Host
A SCSI device with the characteristics of a primary computing device, typically a personal computer, workstation, server, minicomputer, mainframe computer, or auxiliary computing device. A host includes one or more SCSI initiator devices.
IEEE company_id
Synonym for OUI.
I_T nexus
A nexus between a SCSI initiator port and a SCSI target port.
I_T nexus loss
A condition resulting from the events defined by SAM-5 in which the SCSI device performs the I_T nexus loss operations described in
SAM-5, SPC-4, and the applicable command standards.
I_T_L nexus
A nexus between a SCSI initiator port, a SCSI target port, and a logical unit.
I_T_L_Q nexus transaction
The information transferred between SCSI ports in a single data structure with defined boundaries (e.g., an information unit).
Idle power condition
When a device server is capable of responding to all of its supported commands, including media access requests, but commands
may take longer to complete than when in the active power condition.
Implicit head of queue
An optional processing model for specified commands wherein the specified commands may be treated as if they had been received
with a HEAD OF QUEUE task attribute.
Initiator device name
A SCSI device name of a SCSI initiator device or of a SCSI target/initiator device when operating as a SCSI initiator device.
Initiator port
Synonymous with SCSI initiator port.
Initiator port identifier
A value by which a SCSI initiator port is referenced within a SCSI domain.
Initiator port name
A SCSI port name of a SCSI initiator port or of a SCSI target/initiator port when operating as a SCSI initiator port.
Internet protocol domain name
The name of a computer or hierarchy of computers within the domain name system defined by the IETF (see RFC 1035 and RFC
1591). The Internet Assigned Numbers Authority maintains a list of domain name assignments at http://www.iana.org/assignments/
domain-names.
Internet protocol number
A coded value assigned to identify protocols that layer on the Internet protocol (see RFC 791). The Internet protocol number assigned
to the transmission control protocol (TCP, see RFC 793) is six. The Internet Assigned Numbers Authority maintains a list of Internet
protocol number assignments at http://www.iana.org/assignments/protocol-numbers.
Least significant bit (LSB)
In a binary code, the bit or bit position with the smallest numerical weighting in a group of bits that, when taken as a whole, represent
a numerical value (e.g., in the number 0001b, the bit that is set to one).
Left-aligned
A type of field containing ASCII data in which unused bytes are placed at the end of the field (highest offset) and are filled with ASCII
space (20h) characters.
Logical block
A set of data bytes accessed and referenced as a unit.
Logical block address (LBA)
The value used to reference a logical block.

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Logical unit
An externally addressable entity within a SCSI target device that implements a SCSI device model and contains a device server. A
detailed definition of a logical unit may be found in SAM-5.
Logical unit access control descriptor (LUACD)
The structure within an ACE that identifies a logical unit to which access is allowed and specifies the LUN by which the logical unit is
to be accessed.
Logical unit certification list (CLIST)
Defects detected by the device server during an optional certification process performed during the FORMAT UNIT command.
Logical unit inventory
The list of the logical unit numbers reported by a REPORT LUNS command.
Logical unit number (LUN)
An encoded 64-bit identifier for a logical unit. A detailed definition of a logical unit number may be found in SAM-5.
Logical unit reset
A condition resulting from the events defined by SAM-5 in which the logical unit performs the logical unit reset operations described in
SAM-5, SPC-4, and the applicable command standards.
Media
Plural of Medium
Medium
A physical entity that stores data in a nonvolatile manner (i.e., retained through a power cycle) in accordance with commands processed by the device server.
Medium auxiliary memory (MAM)
An auxiliary memory residing on a medium that is accessible to the device server (e.g., a tape cartridge). Medium auxiliary memory
may be nonvolatile and independent of the main function of the device server.
Most significant bit (MSB)
In a binary code, the bit or bit position with the largest numerical weighting in a group of bits that, when taken as a whole, represent a
numerical value (e.g., in the number 1000b, the bit that is set to one).
Name
A label of an object that is unique within a specified context and should never change (e.g., the term name and worldwide identifier
(WWID) may be interchangeable).
Network address authority (NAA)
A field within a name that specifies the format and length of that name. See FC-FS.
Nexus
A relationship between two SCSI devices, and the SCSI initiator port and SCSI target port objects within those SCSI devices.
Non-volatile cache
Cache that retains data through power cycles.
Non-volatile cache memory
Cache memory that retains data through power cycles.
Non-volatile medium
A physical storage medium that retains data written to it for subsequent read operations through power cycles (e.g., a disk within a
device that stores data as magnetic field changes that do not require device power to exist).
Null-padded
A type of field in which unused bytes are placed at the end of the field (i.e., highest offset) and are filled with ASCII null (00h) characters.
Null-terminated
A type of field in which the last used byte (i.e., highest offset) is required to contain an ASCII null (00h) character.
One
The logical true condition of a variable.
Operation Code
The first byte of a SCSI CDB shall contain an operation code identifying the operation being requested by the CDB.
Organizationally unique identifier (OUI)
A numeric identifier that is assigned by the IEEE such that no assigned identifiers are identical. OUI is equivalent to company_id or
IEEE company_id. The IEEE prefers OUI for EUI-48 identifiers and company_id for EUI-64 identifiers. However, the numeric identifier
is called an OUI when it is assigned by the IEEE. The IEEE maintains a tutorial describing the OUI at http://standards.ieee.org/
regauth/oui/.

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Page
A regular parameter structure (or format) used by several commands. These pages are identified with a value known as a page code.
Persist through power loss
An optional capability associated with some features that allows an application client to request that a device server maintain information regarding that feature across power failures.
Persistent reservation holder
The I_T nexus(es) that are allowed to release or change a persistent reservation without preempting it.
Power cycle
Power being removed from and later applied to a SCSI device.
Power on
A condition resulting from the events defined by SAM-5 in which the SCSI device performs the power on operations described in SAM5, SPC-4, and the applicable command standards.
Primary defect list (PLIST)
The list of defects that are considered permanent defects.
Protection information
Fields appended to each logical block that contain a cyclic redundancy check (CRC), an application tag, and a reference tag.
Protocol identifier
A coded value used in various fields to identify the protocol to which other fields apply.
Protocol specific
A requirement that is defined by a SCSI transport protocol standard. A detailed definition of protocol specific may be found in SAM-5.
Protocol standard
A SCSI standard that defines SCSI transport protocol (e.g., SAS, SPI-5, SBP-3, or FCP-2).
Proxy token
An identifier for a logical unit that may be used to gain temporary access to that logical unit in the presence of access controls.
Redundancy group
A grouping of XOR-protected data and associated check data into a single type of data redundancy (see SCC-2). SPC-4 only supports
the XOR type of redundancy.
Request for comment (RFC)
The name given to standards developed by the Internet Engineering Task Force.
Registered
The condition that exists for an I_T nexus following the successful completion of a PERSISTENT RESERVE OUT command with a
REGISTER service action, REGISTER AND IGNORE EXISTING KEY service action, or REGISTER AND MOVE service action and
lasting until the registration is removed.
Registrant
An I_T nexus that is registered.
Right-aligned
A type of field containing ASCII data in which unused bytes are placed at the start of the field (i.e., lowest offset) and are filled with
ASCII space (20h) characters.
Relative port identifier
An identifier for a SCSI port that is unique within a SCSI device. Application clients may use the SCSI Ports VPD page to determine
relative port identifier values.
Relative initiator port identifier
A relative port identifier for a SCSI initiator port.
Relative target port identifier
A relative port identifier for a SCSI target port.
SCSI device
A device that contains one or more SCSI ports that are connected to a service delivery subsystem and supports a SCSI application
protocol.
SCSI device name
A name of a SCSI device that is world wide unique within the protocol of a SCSI domain in which the SCSI device has SCSI ports. The
SCSI device name may be made available to other SCSI devices or SCSI ports in protocol specific ways.
SCSI domain
The interconnection of two or more SCSI devices and a service delivery subsystem. A detailed definition of a SCSI Domain may be
found in SAM-5.

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SCSI initiator device
A SCSI device containing application clients and SCSI initiator ports that originate device service and task management requests to
be processed by a SCSI target device and receives device service and task management responses from SCSI target devices.
SCSI initiator port
A SCSI initiator device object acts as the connection between application clients and the service delivery subsystem through which
requests and responses are routed.
SCSI port
A port of a SCSI device that connects the application client, device server or task manager to the service delivery subsystem.
SCSI port identifier
A value by which a SCSI port is referenced within a domain. The SCSI port identifier is either an initiator port identifier or a target port
identifier.
SCSI port name
A name of a SCSI port that is world wide unique within the protocol of the SCSI domain of that SCSI port. The name may be made
available to other SCSI devices or SCSI ports in that SCSI domain in protocol specific ways.
SCSI Ports VPD page
A VPD page that allows retrieval of information about all the SCSI ports in a SCSI target device or SCSI target/initiator device.
SCSI target device
A SCSI device containing logical units and SCSI target ports that receives device service and task management requests for processing and sends device service and task management responses to SCSI initiator devices.
SCSI target port
A SCSI target device object that acts as the connection between device servers and task managers and the service delivery subsystem through which requests and responses are routed.
SCSI transport protocol standard
A SCSI standard that defines a SCSI transport protocol (e.g., FCP-2, SAS, SRP, or SBP-3).
Sense data
Data describing an error or exceptional condition that a device server delivers to an application client in the same I_T_L_Q nexus
transaction as a CHECK CONDITION status or in response to a REQUEST SENSE command. The format of sense data is defined in
SPC-4.
Sense key
The contents of the SENSE KEY field in the sense data.
Service action
A request describing a unit of work to be performed by a device server. A service action is an extension of a command.
Service delivery subsystem
That part of a SCSI I/O system that transmits service requests to a logical unit or SCSI target device and returns logical unit or SCSI
target device responses to a SCSI initiator device.
Standby power condition
When a device server is capable of accepting commands, but not capable of processing media access commands.
Status
One byte of response information sent from a device server to an application client upon completion of each command.
Storage array controller
Any combination of an initiator and application clients (see SAM-5) that originates SCSI commands, converts input LUNs to output
LUNs, and converts input LBAs to output LBAs. A storage array controller organizes a group of direct-access block devices into various objects (e.g., redundancy groups and volume sets). See SCC-2.
System
One or more SCSI domains operating as a single configuration.
Target device name
A SCSI device name of a SCSI target device or of a SCSI target/initiator device when operating as a SCSI target device.
Target port
Synonymous with SCSI target port.
Target port asymmetric access state
The characteristic that defines the behavior of a target port and the allowable command set for a logical unit when commands and task
management functions are routed through the target port maintaining that state.
Target port group
A set of target ports that are in the same target port asymmetric access state at all times.

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Target port group asymmetric access state
The target port asymmetric access state common to the set of target ports in a target port group.
Target port identifier
A value by which a SCSI target port is referenced within a SCSI domain.
Target port name
A SCSI port name of a SCSI target port or of a SCSI target/initiator port when operating as a SCSI target port.
Task
An object within a logical unit that represents the work associated with a command or a group of linked commands. A detailed definition of a task may be found in SAM-5.
Task set
A group of tasks within a logical unit, whose interaction is dependent on the task management (queuing) and ACA rules. See SAM-5
and the Control mode page.
TCP port numbers
One of the data needed to establish a TCP connection. TCP port numbers may be assigned to protocols that layer on TCP by the
Internet Assigned Numbers Authority. The Internet Assigned Numbers Authority maintains a list of TCP port number assignments at
http://www.iana.org/assignments/ port-numbers.
Third-party command
A command sent to one SCSI device requesting than an operation be performed involving two other SCSI devices (e.g., the
EXTENDED COPY command may perform copy operations between two or more SCSI devices none of which are the SCSI device to
which the EXTENDED COPY command was sent).
Unit attention condition
A state that a logical unit maintains while it has asynchronous status information to report to the initiator ports associated with one or
more I_T nexuses. See SAM-5.
Universal time (UT)
The time at longitude zero, colloquially known as Greenwich Mean Time. See http://aa.usno.navy.mil/faq/docs/UT.html.
URI Schemes
The Internet Assigned Numbers Authority maintains a list of schemes for URI and URL names at http://www.iana.org/assignments/urischemes.
User data
Data contained in logical blocks that is not protection information.
UTF-8
A character set that is a transformation format of the character set defined by ISO 10646. See RFC 2279.
Vendor specific (VS)
Something (e.g., a bit, field, or code value) that is not defined by SPC-4 and may be vendor defined.
Volatile cache memory or Volatile cache
Cache memory that does not retain data through power cycles.
Volatile medium
Medium that does not retain data written to it for a subsequent read operation through power cycles (e.g., a silicon memory device that
loses data written to it if device power is lost).
Well known logical unit
A logical unit that only does specific functions. Well known logical units allow an application client to issue requests to receive and
manage specific information usually relating to a SCSI target device.
Well known logical unit number (W-LUN)
The logical unit number that identifies a well known logical unit.
XOR operation
Performing an XOR bitwise on two identical-sized multiple-bit input values (e.g., the current value of a logical block and the new value
for that logical block). In a storage array implementing a redundancy group, the XOR operation is used in error correction algorithms
and may be performed by the storage array controller or by the direct-access block devices.
XOR-protected data
Logical blocks, including user data and protection information, if any, that are part of a redundancy group.
Zero
The logical false condition of a variable.
Zero-padded
A type of field in which unused bytes are placed at the end of the field (i.e., highest offset) and are filled with zeros.

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1.2

Symbols and abbreviations
See Table 1 for abbreviations of standards bodies (e.g., ISO). Additional symbols and abbreviations used in the manual include:

Abbreviation
<
>
ACE
ACL
ACA
ASC
ASCII
ASCQ
ATA
CDB
CRC
CLIST
D_ID
DLIST
ECC
EUI-48
EUI-64
FC-FS
FCP-2
GLIST
HTTP
I/O
ID
IEC
IEEE
IETF
IP
IPv4
IPv6
iSCSI
ISO
LBA
LSB
LUACD
LUN
MAM
MMC-5
MSB
NAA
n/a
INCITS
OSD
OUI
PLIST
RAID
RBC
RDMA
RFC
RMC
SAM-4
SAM-5
SAT
SBC-2
SBC-3
SCSI
SES

Meaning
less than
greater than
Access Control list Entry
Access Control List
Auto Contingent Allegiance
Additional Sense Code
American Standard Code for Information Interchange
Additional Sense Code Qualifier
AT Attachment (see www.t13.org)
Command Descriptor Block
Cyclic Redundancy Check
logical unit certification list
Destination Identifier (defined in FC-FS)
data defect list
error correcting code
Extended Unique Identifier, a 48-bit globally unique identifier
Extended Unique Identifier, a 64-bit globally unique identifier
Fibre Channel Framing and Signaling Interface
Fibre Channel Protocol for SCSI -2
grown defect list
Hypertext Transfer Protocol (see RFC 2616)
input/output
Identifier or Identification
International Electrotechnical Commission
Institute of Electrical and Electronics Engineers
Internet Engineering Task Force
Internet Protocol
Internet Protocol version 4
Internet Protocol version 6
Internet SCSI
Organization for International Standards
Logical Block Address
Least Significant Bit
Logical Unit Access Control Descriptor
Logical Unit Number
Medium Auxiliary Memory
SCSI Multi-Media Commands -5
Most Significant Bit
Network Address Authority
not applicable
InterNational Committee for Information Technology Standards
Object-based Storage Devices Commands
Organizationally Unique Identifier
primary defect list
Redundant Array of Independent Disks
SCSI Reduced Block Commands
Remote Direct Memory Access (see SRP)
Request For Comments
SCSI Reduced Multi-Media Commands
SCSI Architecture Model -4
SCSI Architecture Model -5
SCSI / ATA Translation
SCSI Block Commands -2
SCSI Block Commands -3
The architecture defined by the family of standards described in clause 1
SCSI-3 Enclosure Services

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SES-2
SPC
SPC-3
SPC-4
SPI-5
SRP
SSC-3
TCP
URI
URL
UT
USB
VPD
VS
W-LUN
1.3

SCSI Enclosure Services -2
SCSI-3 Primary Commands (ANSI INCITS 301-1997)
SCSI Primary Commands -3
SCSI Primary Commands -4
SCSI Parallel Interface -5
SCSI RDMA Protocol
SCSI Stream Commands -2
Transmission Control Protocol (see RFC 793)
Uniform Resource Identifier (see RFC 2396 and RFC 3305)
Uniform Resource Locator (see RFC 2396 and RFC 3305)
Universal time
Universal Serial Bus (see www.usb.org)
Vital Product Data
Vendor Specific
Well known logical unit number

Keywords

Expected
A keyword used to describe the behavior of the hardware or software in the design models assumed by this manual. Other hardware
and software design models may also be implemented.
Ignored
A keyword used to describe an unused bit, byte, word, field or code value. The contents or value of an ignored bit, byte, word, field or
code value shall not be examined by the receiving SCSI device and may be set to any value by the transmitting SCSI device.
Invalid
A keyword used to describe an illegal or unsupported bit, byte, word, field or code value. Receipt of an invalid bit, byte, word, field or
code value shall be reported as an error.
Mandatory
A keyword indicating an item that is required to be implemented as defined in this manual.
May
A keyword that indicates flexibility of choice with no implied preference (equivalent to “may or may not”).
May not
Keywords that indicate flexibility of choice with no implied preference (equivalent to “may or may not”).
Need not
Keywords indicating a feature that is not required to be implemented (equivalent to “is not required to”).
Obsolete
A keyword indicating that an item was defined in prior SCSI standards but has been removed from this manual.
Optional
A keyword that describes features that are not required to be implemented by the standard. However, if any optional feature defined in
the standard is implemented, then it shall be implemented as defined in this manual.
Reserved
A keyword referring to bits, bytes, words, fields and code values that are set aside for future standardization. A reserved bit, byte, word
or field shall be set to zero, or in accordance with a future extension to this manual. Recipients are not required to check reserved bits,
bytes, words or fields for zero values. Receipt of reserved code values in defined fields shall be reported as an error.
Restricted
A keyword referring to bits, bytes, words, and fields that are set aside for use in other SCSI standards. A restricted bit, byte, word, or
field shall be treated as a reserved bit, byte, word or field for the purposes of the requirements defined in this manual.
Shall
A keyword indicating a mandatory requirement. Designers are required to implement all such mandatory requirements to ensure
interoperability with other products that conform to this manual.
Should
A keyword indicating flexibility of choice with a strongly preferred alternative; equivalent to the phrase “it is strongly recommended.”
Vendor-specific
Something (e.g., a bit, field, or code value) that is not defined by this manual and may be used differently in various implementations.

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1.4

Conventions

Certain words and terms used in this manual have a specific meaning beyond the normal English meaning. These words and terms are
defined either in this clause or in the text where they first appear. Names of commands, status codes, sense keys, and additional sense
codes are in all uppercase (e.g., REQUEST SENSE).
If there is more than one CDB length for a particular command (e.g., MODE SENSE(6) and MODE SENSE(10)) and the name of the
command is used in a sentence without any CDB length descriptor (e.g., MODE SENSE), then the condition specified in the sentence
applies to all CDB lengths for that command.
Names of fields and state variables are in uppercase (e.g. NAME). When a field or state variable name contains acronyms, uppercase
letters may be used for readability. Normal case is used when the contents of a field or state variable are being discussed. Fields or state
variables containing only one bit are usually referred to as the NAME bit instead of the NAME field.
Normal case is used for words having the normal English meaning.
A binary number is represented in this manual by any sequence of digits comprised of only the Western-Arabic numerals 0 and 1
immediately followed by a lower-case b (e.g., 0101b). Underscores or spaces may be included between characters in binary number
representations to increase readability or delineate field boundaries (e.g., 0 0101 1010b or 0_0101_1010b).
A hexadecimal number is represented in this manual by any sequence of digits comprised of only the Western-Arabic numerals 0 through
9 and/or the upper-case English letters A through F immediately followed by a lower-case h (e.g., FA23h). Underscores or spaces may be
included in hexadecimal number representations to increase readability or delineate field boundaries (e.g., B FD8CFA23h or
B_FD8C_FA23h).
A decimal number is represented in this manual by any sequence of digits comprised of only the Western-Arabic numerals 0 through 9 not
immediately followed by a lower-case b or lower-case h (e.g., 25).
When the value of the bit or field is not relevant, x or xx appears in place of a specific value.
This manual uses the ISO convention for representing decimal numbers (e.g., the thousands and higher multiples are separated by a
space and a comma is used as the decimal point). Table 1 shows some examples of decimal numbers represented using the ISO and
American conventions.
Table 1

ISO v American Numbering Conventions
ISO

American

0,6
3,141 592 65
1 000
1 323 462

0.6
3.14159265
1,000
1,323,462.95

Lists sequenced by letters (e.g., a) red, b) blue, c) green) show no ordering relationship between the listed items. Lists sequenced by
numbers (e.g., 1) red, 2) blue, 3) green) show an ordering relationship between the listed items.
If a conflict arises between text, tables or figures, the order of precedence to resolve the conflicts is text, then tables, and finally figures. Not
all tables or figures are fully described in the text. Tables show data format and values. Notes do not constitute any requirements for
implementors.

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2.0

General Concepts

This manual defines behaviors that are common to all Seagate SCSI device models. This manual defines the SCSI commands that are
basic to more than one disk drive model and the SCSI commands that may apply to any SCSI Interface, including Parallel, Fibre Channel,
and Serial Attached SCSI (SAS).
2.1

Command Descriptor Block (CDB)

2.1.1

CDB usage and structure

A command is communicated by sending a command descriptor block (CDB) to the device server. For several commands, the CDB is
accompanied by a list of parameters in the Data-Out Buffer. See the specific commands for detailed information.
If a logical unit validates reserved CDB fields and receives a reserved field within the CDB that is not zero, then the logical unit shall
terminate the command with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code
set to INVALID FIELD IN CDB.
If a logical unit receives a reserved CDB code value in a field other than the OPERATION CODE field, then the logical unit shall terminate
the command with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to
INVALID FIELD IN CDB.
The fixed length CDB formats are described in 2.1.2. The variable length CDB formats are described in 2.1.4. The CDB fields that are
common to most commands are described in 2.1.5. The fields shown in 2.1.2 and 2.1.3 and described in 2.1.4 are used consistently by
most commands. However, the actual usage of any field (except OPERATION CODE and CONTROL) is described in the subclause
defining that command. If a device server receives a CDB containing an operation code that is invalid or not supported, the command shall
be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to
INVALID COMMAND OPERATION CODE.
For all commands, if there is an invalid parameter in the CDB, the device server shall terminate the command without altering the medium.
2.1.2

The fixed length CDB formats

All fixed length CDBs shall have an OPERATION CODE field as their first byte and a CONTROL byte as their last byte. Table 2 shows the
typical format of a 6-byte CDB. Table 3 shows the typical format of a 10-byte CDB. Table 4 shows the typical format of a 12-byte CDB. .
Table 5 shows the format of a 16-byte CDB for commands that provide for a long LBA.
Table 2
Bit
Byte

Typical CDB for 6-byte commands
7

6

5

3

2

1

0

OPERATION CODE

0
1

4

Miscellaneous CDB information

2
3

(MSB)

LOGICAL BLOCK ADDRESS (if required)

4

TRANSFER LENGTH (if required)
PARAMETER LIST LENGTH (if required)
ALLOCATION LENGTH (if required)

5

CONTROL

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Table 3
Bit
Byte

Typical CDB for 10-byte commands
7

6

5

4

2

2

1

Miscellaneous CDB information

SERVICE ACTION (if required)

(MSB)
LOGICAL BLOCK ADDRESS (if required)

...

(LSB)

5
Miscellaneous CDB information

6

8

TRANSFER LENGTH (if required)
PARAMETER LIST LENGTH (if required)
ALLOCATION LENGTH (if required)

9

CONTROL

7

Table 4
Bit
Byte

(MSB)

2

(LSB)

Typical CDB for 12-byte commands
7

6

5

4

3

2

1

Miscellaneous CDB information

SERVICE ACTION (if required)

(MSB)
LOGICAL BLOCK ADDRESS (if required)

...

(LSB)

5
6

(MSB)

TRANSFER LENGTH (If required)
PARAMETER LIST LENGTH (if required)
ALLOCATION LENGTH (if required)

...
9
10

Miscellaneous CDB information

11

CONTROL

Table 5
Bit
Byte

7

6

5

4

3

OPERATION CODE

1

Miscellaneous CDB information

2

1

0

(MSB)

...

LOGICAL BLOCK ADDRESS
(LSB)

9
10

(LSB)

Typical CDB for long LBA 16-byte commands

0

2

0

OPERATION CODE

0
1

0

OPERATION CODE

0
1

3

(MSB)

...
13

TRANSFER LENGTH (If required)
PARAMETER LIST LENGTH (if required)
ALLOCATION LENGTH (if required)

14

Miscellaneous CDB information

15

Control

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2.1.3

The variable length CDB formats

The first byte of a variable length CDB shall contain the operation code 7Fh. The CONTROL byte is the second byte in the variable length
CDB (see table 6)
Table 6
Bit
Byte

Typical variable length CDB
7

6

5

4

3

0

OPERATION CODE (7Fh)

1

CONTROL

2

Miscellaneous CDB information

3

Miscellaneous CDB information

4

Miscellaneous CDB information

5

Miscellaneous CDB information

6

Miscellaneous CDB information

7

ADDITIONAL CDB LENGTH (n–7)

8

(MSB)

9
10

SERVICE ACTION

2

1

0

(LSB)

(MSB)

...
n

Service Action specific fields
(LSB)

ADDITIONAL CDB LENGTH field
The ADDITIONAL CDB LENGTH field specifies the number of additional CDB bytes. This value in the ADDITIONAL CDB LENGTH field
shall be a multiple of 4. If the number of CDB bytes delivered by the service delivery subsystem is not sufficient to contain the number of
bytes specified by the ADDITIONAL CDB LENGTH field, then the command shall be terminated with CHECK CONDITION status, with the
sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN CDB.
SERVICE ACTION field
The SERVICE ACTION field specifies the action being requested by the application client. The SERVICE ACTION field is required in the
variable length CDB format and is described in 4.3.4.2. Each service action code description defines a number of service action specific
fields that are needed for that service action.

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A 32-byte variable length CDB format is defined for long LBA operations (see table 7)
Table 7
Bit
Byte

Typical variable length CDB for long LBA 32-byte commands
7

6

5

4

3

0

OPERATION CODE (7Fh)

1

CONTROL

2

Miscellaneous CDB information

3

Miscellaneous CDB information

4

Miscellaneous CDB information

5

Miscellaneous CDB information

6

Miscellaneous CDB information

7

Additional CDB Length (n–7) [9]

8

(MSB)

SERVICE ACTION

9
10

Miscellaneous CDB information

DPO

FUA

0

(LSB)
Miscellaneous CDB information

(MSB)

...

LOGICAL BLOCK ADDRESS
(LSB)

19
20

1

Miscellaneous CDB information

11
12

2

(MSB)

Miscellaneous CDB information

...
(LSB)

27
28

(MSB)

...
31

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TRANSFER LENGTH (If required)
PARAMETER LIST LENGTH (if required)
ALLOCATION LENGTH (if required)

(LSB)

15

2.2

Common CDB fields

2.2.1

Operation Code

The first byte of a SCSI CDB shall contain an operation code identifying the operation being requested by the CDB. Some operation codes
provide for modification of their operation based on a service action (see 2.1.4.2). In such cases, the operation code and service action
code combine to identify the operation being requested. The location of the SERVICE ACTION field in the CDB varies depending on the
operation code value.
The OPERATION CODE (see table 9) of the CDB has a GROUP CODE field and a COMMAND CODE field. The three-bit GROUP CODE
field provides for eight groups of command codes. The five-bit COMMAND CODE field provides for thirty-two command codes in each
group. A total of 256 possible operation codes exist. Operation codes are defined in this manual and other command standards. The group
code value shall determine the length of the CDB (see table 10).
Table 8

OPERATION CODE byte

Bit

7

6

5

4

3

GROUP CODE

2

1

0

COMMAND CODE

The value in the GROUP CODE field specifies one of the groups shown in Table 9.
Table 9

Group Code values

Group Code

Meaning

Typical CDB Format

000b

6 byte commands

see Table 2

001b

10 byte commands

see Table 3

010b

10 byte commands

see Table 3

011b

Reserved

[a]

100b

16 byte commands

see Table 5 and Table 6

101b

12 byte commands

see Table 4

110b

Vendor Specific

111b
Vendor Specific
[a] The format of the commands using operation code 7Fh is described in 2.1.3.
With the exception of operation code 7Fh, all group code 011b operation
codes are reserved.
2.2.2

SERVICE ACTION

All CDB formats except the 6-byte format provide for a SERVICE ACTION field containing a coded value identifying a function to be
performed under the more general command function specified in the OPERATION CODE field. While the SERVICE ACTION field is
defined for CDB formats, it is used as described in this subclause only in those CDB formats that contain a SERVICE ACTION field. When
the specific field SERVICE ACTION is not defined in a CDB format, the bits identified as the SERVICE ACTION field in a CDB shall be
used or reserved as specified by the particular CDB format.
2.2.3

Logical block address

The logical block addresses on a logical unit or within a volume or partition shall begin with block zero and be contiguous up to the last
logical block of that logical unit or within that volume or partition.
A six-byte CDB may contain a 21-bit LOGICAL BLOCK ADDRESS field. The ten-byte and the twelve-byte CDBs may contain 32-bit
LOGICAL BLOCK ADDRESS fields. The sixteen-byte CDB has two formats: one allows a 32-bit LOGICAL BLOCK ADDRESS field (see
Table 5) and the other allows a 64-bit LOGICAL BLOCK ADDRESS field (see Table 6). LOGICAL BLOCK ADDRESS fields in additional
parameter data have their length specified for each occurrence. See the specific command descriptions.

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2.2.4

TRANSFER LENGTH

The TRANSFER LENGTH field specifies the amount of data to be transferred, usually the number of blocks. Some commands use transfer
length to specify the requested number of bytes to be sent as defined in the command description.
Commands that use one byte for the TRANSFER LENGTH field may allow up to 256 blocks or 256 bytes of data to be transferred by one
command.
In commands that use multiple bytes for the TRANSFER LENGTH field, a transfer length of zero specifies that no data transfer shall take
place. A value of one or greater specifies the number of blocks or bytes that shall be transferred. Refer to the specific command description
for further information.
2.2.5

PARAMETER LIST LENGTH

The PARAMETER LIST LENGTH field is used to specify the number of bytes sent from the Data-Out Buffer. This field is typically used in
CDBs for parameters that are sent to a device server (e.g., mode parameters, diagnostic parameters, log parameters). A parameter list
length of zero specifies that no data shall be transferred. This condition shall not be considered as an error, unless otherwise specified.
2.2.6

ALLOCATION LENGTH

The ALLOCATION LENGTH field specifies the maximum number of bytes that an application client has allocated in the Data-In Buffer. An
allocation length of zero specifies that no data shall be transferred. This condition shall not be considered as an error. The device server
shall terminate transfers to the Data-In Buffer when the number of bytes specified by the ALLOCATION LENGTH field have been
transferred or when all available data have been transferred, whichever is less. The allocation length is used to limit the maximum amount
of variable length data (e.g., mode data, log data, diagnostic data) returned to an application client. If the information being transferred to
the Data-In Buffer includes fields containing counts of the number of bytes in some or all of the data, then the contents of these fields shall
not be altered to reflect the truncation, if any, that results from an insufficient ALLOCATION LENGTH value, unless this manual describes
the Data-In Buffer format states otherwise.
If the amount of information to be transferred exceeds the maximum value that the ALLOCATION LENGTH field is capable of specifying,
the device server shall transfer no data and terminate the command with CHECK CONDITION status, with the sense key set to ILLEGAL
REQUEST, and the additional sense code set to INVALID FIELD IN CDB.
2.2.7

CONTROL

The CONTROL byte has the same definition for all commands.
All CDBs shall contain a CONTROL byte (see table 10). The location of the CONTROL byte within a CDB depends on the CDB format (see
“<$T and “<$T).
Table 10
Bit

Control Byte
7

6

Vendor Specific
[1]
[2]

5

4

3

Reserved

2
NACA

1

0

Obsolete [1] Obsolete [2]

Bit 1 of the Control byte was formerly the FLAG bit. See FLAG bit below).
Bit 0 of the Control byte was formerly the LINK bit. See LINK bit below).

All SCSI transport protocol standards shall define the functionality needed for a logical unit to implement the NACA bit and LINK bit.
NACA (Normal ACA) bit
The NACA (Normal ACA) bit specifies whether an auto contingent allegiance (ACA) is established if the command returns with CHECK
CONDITION status. An NACA bit set to one specifies that an ACA shall be established.
0

An NACA bit set to zero specifies that an ACA shall not be established. The actions for ACA are specified in SAM-5. Actions that
may be required when an ACA is not established are described in SAM-5. All logical units shall implement support for the NACA
value of zero and may support the NACA value of one (i.e., ACA). The ability to support a NACA value of one is indicated with the
NORMACA bit in the standard INQUIRY data (see clause 3.6.2)

1

If the NACA bit is set to one but the logical unit does not support ACA, the command shall be terminated with CHECK CONDITION
status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN CDB.

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LINK bit -- declared Obsolete by T10
The LINK bit is used to continue the task across multiple commands. Support for the LINK bit is optional. The application client sets the
LINK bit to one to specify a request for continuation of the task across two or more commands.
If the LINK bit is set to one and the command completes successfully, a logical unit that supports the LINK bit shall continue the task
and return a status of INTERMEDIATE or INTERMEDIATE-CONDITION MET and a service response of LINKED COMMAND
COMPLETE (see SAM-3). If the LINK bit is set to one and the logical unit does not support linked commands, the command shall
be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to
INVALID FIELD IN CDB.D FIELD IN CDB.

1

FLAG bit -- declared Obsolete by T10
Note.

In older model drives the FLAG bit may have been used in conjunction with the LINK bit to notify the initiator in an expedited
manner that the command has completed.

Support for the FLAG bit is a logical unit option. If the LINK bit and FLAG bit are both set to one, and if the command completes with a
status of Intermediate or Intermediate-Condition Met, a drive that supports the FLAG bit returns a service response of Linked Command
Complete (with Flag).
The drive completes the command with a status of Check Condition and a sense key of Illegal Request if:
[a] • The LINK bit is set to one and the drive does not support linked commands, or
[b] • The FLAG bit is set to one and the drive does not support the FLAG bit, or
[c] • The FLAG bit is set to one and the LINK bit is set to zero.
2.2.8

Grouping function

A grouping function is a function that collects information about attributes associated with commands (i.e., information about commands
with the same group value are collected into the specified group). The definition of the attributes and the groups is outside the scope of this
manual. Groups are identified with the GROUP NUMBER field in the CDB of certain commands (e.g., the WRITE (10) command (see
3.60)).
The collection of this information is outside the scope of this manual (e.g., the information may not be transmitted using any SCSI
protocols).
Note.

An example of how grouping could be used, consider two applications using a subsystem; one application streams data and
another accesses data randomly. If the streaming application groups all of its commands with one value (e.g., x), and the random application groups all of its commands with another value (e.g., y), then a group x defined to hold performance metrics
collects all the performance metrics for the streamed commands together and a group y defined to also hold performance
metrics collects all the performance metrics for the random commands together. The result is two sets of performance metrics
(i.e., x and y). A management application then reads the performance metrics and determines if the performance of a specific
group is acceptable.

Support for the grouping function is indicated in the GROUP_SUP bit in the Extended INQUIRY Data VPD page (see 4.4.7).
2.3

Parameter Rounding

Certain parameters sent to a SCSI target port with various commands contain a range of values. Targets may choose to implement only
selected values from this range. When the target receives a value that it does not support, it either rejects the command (CHECK
CONDITION status with Illegal Request Sense key) or it rounds the value received to a supported value. The target shall reject
unsupported values unless rounding is permitted in the description of the parameter.
Rounding of parameter values, when permitted (Rounding is enabled by MODE SELECT command, page code 00h, byte 2, bit 2) shall be
performed as follows:
a SCSI target port that receives a parameter value that is not an exact supported value shall adjust the value to one that it supports and
shall return CHECK CONDITION status with a sense key of Recovered Error. The additional sense code shall be set to Rounded
Parameter. The initiator is responsible to issue an appropriate command to learn what value the target has selected.
Implementor’s Note: Generally, the target should adjust maximum-value fields down to the next lower supported value than the one
specified by the initiator. Minimum-value fields should be rounded up to the next higher supported value than the one specified by the
initiator. In some cases, the type of rounding (up or down) is explicitly specified in the description of the parameter.

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2.4

Sense data

2.4.1

Sense data introduction

Sense data shall be returned in the same I_T_L_Q nexus transaction as a CHECK CONDITION status and as parameter data in response
to the REQUEST SENSE command. Sense data returned in the same I_T_L_Q nexus transaction as a CHECK CONDITION status shall
be either fixed or descriptor format sense data format based on the value of the D_SENSE bit in the Control mode page. The REQUEST
SENSE command may be used to request either the fixed format sense data or the descriptor format sense data.f
The first byte of all sense data contains the RESPONSE CODE field that indicates the error type and format of the sense data (see table
11).
Table 11

Sense data response codes
Error type

Response
Code

Description

Sense data format
Reference

Description

Reference

Reserved

00h - 6Fh
70h

Current

2.4.1.3

Fixed

2.4.1.2

71h

Deferred

2.4.1.4

Fixed

2.4.1.2

72h

Current

2.4.1.3

Descriptor

2.4.1.1

73h

Deferred

2.4.1.4

Descriptor

2.4.1.1

74h - 7Eh

Reserved

7Fh

Vendor specific

The RESPONSE CODE field shall be set to 70h in all unit attention sense data in which:
a) The ADDITIONAL SENSE CODE field is set to 29h; or
b) The additional sense code is set to MODE PARAMETERS CHANGED.
2.4.1.1
2.4.1.1.1

Descriptor format sense data
Descriptor format sense data overview

The descriptor format sense data for response codes 72h (current errors) and 73h (deferred errors) is defined in table 12.
Table 12

Descriptor format sense data

Bit
Byte

7

0

Reserved

6

5

4

3

2

0

RESPONSE CODE (72h or 73h)
Reserved

1

1

SENSE KEY

2

ADDITIONAL SENSE CODE

3

ADDITIONAL SENSE CODE QUALIFIER

4
...

Reserved

6
ADDITIONAL SENSE LENGTH (n-7)

7

Sense Data Descriptor(s)
8

(MSB)

...
...
n

(MSB)

Sense Data Descriptor (first) (see table 13)

Sense Data Descriptor (last) (see table 13)

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RESPONSE CODE field
The contents of the RESPONSE CODE field indicate the error type and format of the sense data (see 2.4.1). For descriptor format sense
data, the RESPONSE CODE field shall be set to 72h or 73h.
SENSE KEY, ADDITIONAL SENSE CODE and ADDITIONAL SENSE CODE QUALIFIER fields
The SENSE KEY, ADDITIONAL SENSE CODE and ADDITIONAL SENSE CODE QUALIFIER fields provide a hierarchy of information.
The hierarchy provides a top-down approach for an application client to determine information relating to the error and exception conditions.
SENSE KEY field
The SENSE KEY field indicates generic information describing an error or exception condition. The sense keys are defined in 2.4.1.5.
ASC (ADDITIONAL SENSE CODE) field
The ADDITIONAL SENSE CODE (ASC) field indicates further information related to the error or exception condition reported in the
SENSE KEY field. Support of the additional sense codes not required by this manual is optional. A list of additional sense codes is in
2.4.1.5. If the device server does not have further information related to the error or exception condition, the additional sense code shall be
set to zero.
ASCQ (ADDITIONAL SENSE CODE QUALIFIER) field
The ADDITIONAL SENSE CODE QUALIFIER (ASCQ) field indicates detailed information related to the additional sense code. If the error
or exception condition is reported by the device server, the value returned shall be as specified in 2.4.1.5. If the device server does not
have detailed information related to the error or exception condition, the additional sense code qualifier shall be set to zero.
ADDITIONAL SENSE LENGTH field
The ADDITIONAL SENSE LENGTH field indicates the number of additional sense bytes that follow. The additional sense length shall be
less than or equal to 244 (i.e., limiting the total length of the sense data to 252 bytes). If the sense data is being returned as parameter data
by a REQUEST SENSE command, then the relationship between the ADDITIONAL SENSE LENGTH field and the CDB ALLOCATION
LENGTH field is defined in 2.2.6.
SENSE DATA DESCRIPTORS field
Sense data descriptors (see table 13) provide specific sense information. A given type of sense data descriptor shall be included in the
sense data only when the information it contains is valid.
Table 13
Bit
Byte

Sense data descriptor format
7

6

5

4

3

0

DESCRIPTOR TYPE

1

ADDITIONAL LENGTH (n-1)

2

2

1

0

(MSB)

...
n

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20

DESCRIPTOR TYPE field
The DESCRIPTOR TYPE field contains a type code (see table 14) that identifies the type of sense data descriptor. No more than one
sense data descriptor of each type shall be included in the descriptor format sense data.
Table 14

Sense data descriptor types

Type

Description

Reference

00h

Information

2.4.1.1.2

01h

Command specific information

2.4.1.1.3

02h

Sense key specific

2.4.1.1.4

03h

Field replaceable unit

2.4.1.1.5

04h

Stream commands

SSC-3

05h

Block commands

SBC-3

06h

OSD object identification

OSD

07h

OSD response integrity check value

OSD

08h

OSD attribute identification

OSD

09h

ATA Return

SAT

0Ah

Another Progress indication

2.4.1.1.6

0Bh - 7Fh

Reserved

80h - FFh

Vendor specific

2.4.1.1.7

ADDITIONAL LENGTH field
The ADDITIONAL LENGTH field indicates the number of sense data descriptor specific bytes that follow in the sense data descriptor.
2.4.1.1.2

Information sense data descriptor

The information sense data descriptor (see table 15) provides information that is device-type or command specific and is defined in a
command standard.
Table 15

Information sense data descriptor format

Bit
Byte

7

6

5

4

3

0

DESCRIPTOR TYPE (00h)

1

ADDITIONAL LENGTH (0Ah)
VALID (1b)

2

2

1

0

Reserved
Reserved

3
(MSB)

4

INFORMATION

...

(LSB)

n
DESCRIPTOR TYPE and ADDITIONAL LENGTH fields

The DESCRIPTOR TYPE and ADDITIONAL LENGTH fields are described in 2.4.1.1.1. For the information sense data descriptor, the
DESCRIPTOR TYPE field shall be set to 00h and the ADDITIONAL LENGTH field shall be set to 0Ah.
VALID bit
The VALID bit shall be set to one.
Note.

In the fixed format sense data, the VALID bit indicates whether the contents of the INFORMATION field is valid as defined by
a command standard. Since the contents of the INFORMATION field are valid whenever an information sense data descriptor
is included in the sense data, the only legal value for the VALID bit is set to one.

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INFORMATION field
The contents of the INFORMATION field are device-type or command specific and are defined in a command standard. When a four byte
quantity is stored in the INFORMATION field, the first four bytes shall be zero.
2.4.1.1.3

Command-specific information sense data descriptor

The command-specific information sense data descriptor (see table 16) provides information that depends on the command on which the
exception condition occurred.
Table 16

Command-specific information sense data descriptor format

Bit
Byte

7

6

5

4

3

0

DESCRIPTOR TYPE (01h)

1

ADDITIONAL LENGTH (0Ah)

2

Reserved

3

Reserved

2

1

0

(MSB)

4

COMMAND SPECIFIC INFORMATION

...

(LSB)

n
DESCRIPTOR TYPE and ADDITIONAL LENGTH fields

The DESCRIPTOR TYPE and ADDITIONAL LENGTH fields are described in 2.4.1.1.1. For the command-specific information sense data
descriptor, the DESCRIPTOR TYPE field shall be set to 01h and the ADDITIONAL LENGTH field shall be set to 0Ah.
COMMAND-SPECIFIC INFORMATION field
The COMMAND-SPECIFIC INFORMATION field contains information that depends on the command on which the exception condition
occurred. When a four byte quantity is stored in the COMMAND-SPECIFIC INFORMATION field, the first four bytes shall be zero.
Further meaning for the COMMAND-SPECIFIC INFORMATION field is defined within the command description in the appropriate command standard (e.g., see SBC-3 for the REASSIGN BLOCKS commands, or SPC-4 for the EXTENDED COPY command).
2.4.1.1.4

Sense key specific sense data descriptor

2.4.1.1.4.1

Sense key specific sense data descriptor introduction

The sense key specific sense data descriptor (see table 17) provides additional information about the exception condition. The format and
content of the sense-key specific data depends on the value in the SENSE KEY field (see 2.4.1.1.1).
Table 17
Bit
Byte

Sense key specific sense data descriptor format
7

6

5

4

3

0

DESCRIPTOR TYPE (02h)

1

ADDITIONAL LENGTH (06h)

2

Reserved

3

Reserved

4

2

1

0

SKSV (1b)

5

SENSE KEY SPECIFIC

6
7

Reserved

DESCRIPTOR TYPE and ADDITIONAL LENGTH fields
The DESCRIPTOR TYPE and ADDITIONAL LENGTH fields are described in 2.4.1.1.1. For the sense-key specific sense data descriptor,
the DESCRIPTOR TYPE field shall be set to 01h and the ADDITIONAL LENGTH field shall be set to 06h.

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SKSV (Sense-key specific valid) bit
The sense-key specific valid (SKSV) bit shall be set to one.
In the fixed format sense data, the SKSV bit indicates whether the contents of the SENSE KEY SPECIFIC field are valid as
defined by a command standard. Since the contents of the SENSE KEY SPECIFIC field are valid whenever a sense key specific sense data descriptor is included in the sense data, the only legal value for the SKSV bit is set to one.

Note.

The definition of the SENSE KEY SPECIFIC field (see table 18) is determined by the value of the SENSE KEY field (see 2.4.1.1.1).
Table 18

Sense key specific field definitions

Sense Key

Sense Key Specific Field Definition

Reference

ILLEGAL REQUEST

Field pointer

2.4.1.1.4.2

HARDWARE ERROR,
MEDIUM ERROR, or
RECOVERED ERROR

Actual retry count

2.4.1.1.4.3

NO SENSE or NOT READY

Progress indication

2.4.1.1.4.4

COPY ABORTED

Segment pointer

2.4.1.1.4.5

UNIT ATTENTION

Unit attention condition queue overflow

2.4.1.1.4.6

All other sense keys

The sense key specific sense data descriptor shall not appear in the descriptor format sense data and the SKSV bit (see 2.4.1.2) shall be set to zero in the fixed format
sense data.

2.4.1.1.4.2

Field pointer sense key specific data

If the SENSE KEY is ILLEGAL REQUEST, then the SENSE KEY SPECIFIC field shall be as shown in table 19.
Table 19

Field pointer sense key specific data

Bit
Byte

7

6

0

SKSV (1b)

C/D

1

(MSB)

5

2

4
Reserved

3

2

BPV
FIELD POINTER

1

0

BIT POINTER

(LSB)

SKSV bit
The SKSV bit is described in 2.4.1.1.4.1 for descriptor format sense data and in 2.4.1.2 for fixed format sense data.
C/D (Command Data) bit
0

A C/D bit set to zero indicates that the illegal parameter is in the data parameters sent by the application client in the Data-Out Buffer.

1

A C/D bit set to one indicates that the illegal parameter is in the CDB.

BPV (Bit Pointer Valid) bit
0

A BPV bit set to zero indicates that the value in the BIT POINTER field is not valid.

1

A BPV bit set to one indicates that the BIT POINTER field specifies which bit of the byte designated by the FIELD POINTER field is
in error. When a multiple-bit field is in error, the BIT POINTER field shall point to the first bit (i.e., the left-most bit) of the field.

FIELD POINTER field
The FIELD POINTER field indicates which byte of the CDB or of the parameter data was in error. Bytes are numbered starting from zero,
as shown in the tables describing the commands and parameters. When a multiple-byte field is in error, the field pointer shall point to the
first byte (i.e., the left-most byte) of the field. If several consecutive bytes are reserved, each shall be treated as a single-byte field.
Note.

The bytes identified as being in error are not necessarily the bytes that need to be changed to correct the problem.

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2.4.1.1.4.3

Actual retry count sense key specific data

If the sense key is HARDWARE ERROR, MEDIUM ERROR, or RECOVERED ERROR, then the SENSE KEY SPECIFIC field shall be as
shown in table 20.
Table 20

Actual retry count sense key specific data

Bit
Byte

7

6

0

SKSV (1b)

1

(MSB)

5

4

3

2

1

0

Reserved
ACTUAL RETRY COUNT

2

(LSB)

SKSV bit
The SKSV bit is described in 2.4.1.1.4.1 for descriptor format sense data and in 2.4.1.2 for fixed format sense data.
ACTUAL RETRY COUNT field
The ACTUAL RETRY COUNT field returns vendor specific information on the number of retries of the recovery algorithm used in attempting to recover an error or exception condition.
Note.

This field should be computed in the same way as the retry count fields within the Read-Write Error Recovery mode page.

2.4.1.1.4.4

Progress indication sense key specific data

If the sense key is NO SENSE or NOT READY, the SENSE KEY SPECIFIC field shall be as shown in table 21.
Table 21

Progress indication sense key specific data

Bit
Byte

7

0

SKSV (1b)

1

(MSB)

6

5

2

4

3

2

1

0

Reserved
PROGRESS INDICATION

(LSB)

SKSV bit
The SKSV bit is described in 2.4.1.1.4.1 for descriptor format sense data and in 2.4.1.2 for fixed format sense data.
PROGRESS INDICATION field
The PROGRESS INDICATION field is a percent complete indication in which the returned value is a numerator that has 65 536 (10000h)
as its denominator. The progress indication shall be based upon the total operation.
Note.

The progress indication should be time related, however this is not an absolute requirement. (E.g., since format time varies
with the number of defects encountered, etc., it is reasonable for the device server to assign values to various steps within the
process. The granularity of these steps should be small enough to provide reasonable assurances to the application client
that progress is being made.)

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2.4.1.1.4.5

Segment pointer sense key specific data

If the sense key is COPY ABORTED, the SENSE KEY SPECIFIC field shall be as shown in table 22.
Table 22

Segment pointer sense key specific data

Bit
Byte

7

6

5

4

3

0

SKSV (1b)

Reserved

SD

Reserved

BPV

1

(MSB)

2

1
BIT POINTER

FIELD POINTER

2

0

(LSB)

SKSV bit
The SKSV bit is described in 2.4.1.1.4.1 for descriptor format sense data and in 2.4.1.2 for fixed format sense data.
SD (SEGMENT DESCRIPTOR) bit
The SD bit indicates whether the field pointer is relative to the start of the parameter list or to the start of a segment descriptor.
0

An SD bit set to zero indicates that the field pointer is relative to the start of the parameter list.

1

An SD bit set to one indicates that the field pointer is relative to the start of the segment descriptor indicated by the third and fourth
bytes of the COMMAND-SPECIFIC INFORMATION field.

BPV (BIT POINTER VALID) bit
0

A BPV bit set to zero indicates that the value in the BIT POINTER field is not valid.

1

A BPV bit set to one indicates that the BIT POINTER field specifies which bit of the byte designated by the FIELD POINTER field is
in error.

When a multiple-bit field is in error, the BIT POINTER field shall point to the most-significant (i.e., left-most) bit of the field.
FIELD POINTER field
The FIELD POINTER field indicates which byte of the parameter list or segment descriptor was in error.
If the parameter list is in excess of 65 528 bytes in length and SD is set to zero, the FIELD POINTER value may not fit in two bytes
provided by the sense key specific sense data descriptor.
2.4.1.1.4.6

Unit attention condition queue overflow sense key specific data

If the sense key is UNIT ATTENTION, the SENSE KEY SPECIFIC field shall be as shown in table 23
Table 23

Unit attention condition queue overflow sense key specific data

Bit
Byte

7

0

SKSV (1b)

6

5

1

4

3

2

1

Reserved

0
OVERFLOW

Reserved

2
SKSV bit

The SKSV bit is described in 2.4.1.1.4.1 for descriptor format sense data and in 2.4.1.2 for fixed format sense data.
OVERFLOW bit
0

An OVERFLOW bit set to zero indicates that the unit attention condition queue has not overflowed.

1

An OVERFLOW bit set to one indicates that the unit attention condition queue has overflowed.

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2.4.1.1.5

Field replaceable unit sense data descriptor

The field replaceable unit sense data descriptor (see table 24) provides information about a component that has failed.
Table 24
Bit
Byte

Field replaceable unit sense data descriptor format
7

6

5

4

3

0

DESCRIPTOR TYPE (03h)

1

ADDITIONAL LENGTH (02h)

2

Reserved

3

FIELD REPLACEABLE UNIT CODE

2

1

0

DESCRIPTOR TYPE and ADDITIONAL LENGTH fields
The DESCRIPTOR TYPE and ADDITIONAL LENGTH fields are described in 2.4.1.1.1. For the field replaceable unit sense data descriptor, the DESCRIPTOR TYPE field shall be set to 03h and the ADDITIONAL LENGTH field shall be set to 02h.
FIELD REPLACEABLE UNIT CODE field
Non-zero values in the FIELD REPLACEABLE UNIT CODE field are used to identify a component that has failed. A value of zero in this
field indicates that no specific component has been identified to have failed or that the data is not available. The format of this information
is not specified by this manual. Additional information about the field replaceable unit may be available in the ASCII Information VPD page,
if supported by the device server.
2.4.1.1.6

Progress indication sense data descriptor

If the sense key is set to NO SENSE or NOT READY, the progress indication sense data descriptor (see table 25) may be used to provide
a progress indication for one operation other than the one described by the non-descriptor fields in 2.4.1.1.1. The sense data should
include one progress indication sense data descriptor for each operation for which the device server is able to report progress other than
the operation described by the non-descriptor fields in 2.4.1.1.1.
Table 25
Bit
Byte

Progress indications sense data descriptor format
7

6

5

4

3

DESCRIPTOR TYPE

1

ADDITIONAL LENGTH

0

(06h)

2

SENSE KEY

3

ADDITIONAL SENSE CODE

4

ADDITIONAL SENSE CODE QUALIFIER

5

Reserved
MSB

1

(0Ah)

0

6

2

PROGRESS INDICATION

7

LSB

DESCRIPTOR TYPE and ADDITIONAL LENGTH fields
The DESCRIPTOR TYPE field and ADDITIONAL LENGTH field are described in 2.4.1.1.1.
For the progress indications sense data descriptor:
a) the DESCRIPTOR TYPE field shall be set to 0Ah; and
b) the ADDITIONAL LENGTH field shall be set to 06h.
SENSE KEY field
The SENSE KEY field indicates the operation for which this progress indication sense data descriptor provides a progress indication. A list
of sense key values is in 2.4.1.5.
ADDITIONAL SENSE CODE field
The ADDITIONAL SENSE CODE (ASC) field indicates the operation for which this progress indication sense data descriptor provides a
progress indication. A list of additional sense codes is in 2.4.1.6.

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ADDITIONAL SENSE CODE QUALIFIER field
The ADDITIONAL SENSE CODE QUALIFIER (ASCQ) field indicates detailed information related to the additional sense code for the operation for which this progress indication sense data descriptor provides a progress indication. The value returned in the ADDITIONAL
SENSE CODE QUALIFIER (ASCQ) field shall be as specified in 2.4.1.6.
PROGESS INDICATION field
The PROGESS INDICATION field indicates a percent complete for the operation indicated by the SENSE KEY field, the ADDITIONAL
SENSE CODE field, and the ADDITIONAL SENSE CODE QUALIFIER field. The value in the PROGESS INDICATION field shall be as
defined in 2.4.1.1.4.4.
2.4.1.1.7

Vendor specific sense data descriptors

Vendor specific sense data descriptors (see table 26) contain vendor specific data that further defines the nature of the exception
condition.
Table 26
Bit
Byte

Vendor specific sense data descriptor format
7

6

5

4

3

0

DESCRIPTOR TYPE (80h - FFh)

1

ADDITIONAL LENGTH (n-1)

2

2

1

0

(MSB)
VENDOR SPECIFIC

...

(LSB)

n
DESCRIPTOR TYPE and ADDITIONAL LENGTH fields

The DESCRIPTOR TYPE and ADDITIONAL LENGTH fields are described in 2.4.1.1.1. For the vendor specific sense data descriptor, the
DESCRIPTOR TYPE field shall be set to a value between 80h and FFh, inclusive.
2.4.1.2

Fixed format sense data

The fixed format sense data for response codes 70h (current errors) and 71h (deferred errors) is defined in table 27.
Table 27
Bit
Byte
0
1
2
3
...
6
7
8
...
11
12
13
14
15
...
17
18
...
n

Fixed format sense data
7

6

5

VALID
FILEMARK
(MSB)

EOM

ILI

4

3

2

1

0

RESPONSE CODE (70H OR 71H)
Obsolete
Reserved
SENSE KEY
INFORMATION
(LSB)
ADDITIONAL SENSE LENGTH (N-7)

(MSB)
COMMAND-SPECIFIC INFORMATION
(LSB)
ADDITIONAL SENSE CODE
ADDITIONAL SENSE CODE QUALIFIER
FIELD REPLACEABLE UNIT CODE
SKSV

(MSB)
SENSE KEY SPECIFIC
(LSB)

(MSB)

SCSI Commands Reference Manual, Rev. H

ADDITIONAL SENSE BYTES
(LSB)

27

VALID bit
0

A VALID bit set to zero indicates that the INFORMATION field is not defined in this manual or any command standard.

1

A VALID bit set to one indicates the INFORMATION field contains valid information as defined in this manual or a command standard.

RESPONSE CODE field
The contents of the RESPONSE CODE field indicate the error type and format of the sense data (see 2.4.1). For fixed format sense data,
the RESPONSE CODE field shall be set to 70h or 71h.
FILE MARK bit
See the SSC-3 READ and SPACE commands for examples of FILEMARK bit usage.
EOM (End-of-Medium) bit
See the SSC-3 READ, SPACE, and WRITE commands for examples of end-of-medium (EOM) bit usage.
ILI (Incorrect length indicator) Bit
See the SBC-3 READ LONG, SBC-3 WRITE LONG, and SSC-3 READ commands and for examples of incorrect length indicator (ILI) bit
usage.
SENSE KEY, ADDITONAL SENSE CODE, and ADDITIONAL SENSE CODE QUALIFIER fields
The SENSE KEY, ADDITIONAL SENSE CODE, and ADDITIONAL SENSE CODE QUALIFIER fields are described in 4.5.2.1.
INFORMATION field
The contents of the INFORMATION field is device-type or command specific and is defined within the appropriate standard for the device
type or command of interest. targets shall implement the INFORMATION field. Unless specified otherwise, this field contains:
a) the unsigned LOGICAL BLOCK ADDRESS associated with the sense key, for direct-access devices (device type 0), write-once
devices (device type 4), CD-ROM devices (device type 5), and optical memory devices (device type 7);
b) the difference (residue) of the requested length minus the actual length in either bytes or blocks, as deter-mined by the command,
for sequential-access devices (device type 1), printer devices (device type 2), processor devices (device type 3) and some direct
access device commands, except as defined for d) below. Negative values are indicated by two's complement notation;
c) the difference (residue) of the requested number of blocks minus the actual number of blocks copied or compared for the current
segment descriptor of a COPY, COMPARE, COPY AND VERIFY, or Extended COPY command; or
d) for sequential-access devices operating in buffered modes 1h or 2h that detect an unrecoverable write error when unwritten data
blocks, filemarks, or setmarks remain in the buffer, the value of the information field for all commands shall be:
A) the total number of data blocks, filemarks, and setmarks in the buffer if the device is in fixed block mode (block length field of
the MODE SENSE block descriptor is non-zero and the fixed bit of the WRITE command is one); or
B) the number of bytes in the buffer, including filemarks and setmarks, if the device is in variable mode (the fixed bit of the
WRITE command is zero).
ADDITIONAL SENSE LENGTH field
The ADDITIONAL SENSE LENGTH field indicates the number of additional sense bytes that follow. The additional sense length shall be
less than or equal to 244 (i.e., limiting the total length of the sense data to 252 bytes). If the sense data is being returned as parameter data
by a REQUEST SENSE command, then the relationship between the ADDITIONAL SENSE LENGTH field and the CDB ALLOCATION
LENGTH field is defined in 2.2.6.
COMMAND-SPECIFIC INFORMATION field
The COMMAND-SPECIFIC INFORMATION field contains information that depends on the command on which the exception condition
occurred.
FIELD REPLACEABLE UNIT CODE field
The FIELD REPLACEABLE UNIT CODE field is described in 2.4.1.1.5.
SKSV (Sense-key Specific Valid) bit
1

A sense-key specific valid (SKSV) bit set to one indicates the SENSE KEY SPECIFIC field contains valid information as defined in
this manual.

0

An SKSV bit set to zero indicates that the SENSE KEY SPECIFIC field is not as defined by this manual.

SENSE KEY SPECIFIC field
The SENSE KEY SPECIFIC field is described in 2.4.1.1.4.
The additional sense bytes may contain vendor specific data that further defines the nature of the exception condition.
SCSI Commands Reference Manual, Rev. H

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2.4.1.3

Current errors

Response codes 70h and 72h (current error) indicate that the sense data returned is the result of an error or exception condition on the
task that returned the CHECK CONDITION status or a protocol specific failure condition. This includes errors generated during processing
of the command. It also includes errors not related to any command that are detected during processing of a command (e.g., disk servomechanism failure, off-track errors, or power-up test errors).
2.4.1.4

Deferred errors

Response codes 71h and 73h (deferred error) indicate that the sense data returned is the result of an error or exception condition that
occurred during processing of a previous command for which GOOD, CONDITION MET, INTERMEDIATE, and INTERMEDIATECONDITION MET status has already been returned. Such commands are associated with the use of the immediate bit and with some
forms of caching. Device servers that implement these features shall implement deferred error reporting.
The deferred error may be indicated by returning CHECK CONDITION status to an application client accessed through a defined I_T
nexus as described in this subclause.
If the task terminates with CHECK CONDITION status and the sense data describes a deferred error, the command for the terminated task
shall not have been processed. After the device server detects a deferred error condition, it shall return a deferred error according to the
following rules:
(a)

If no external intervention is necessary to recover a deferred error, a deferred error indication shall not be returned unless
required by the error handling parameters of a MODE SELECT command. The occurrence of the error may be logged;

(b)

If it is possible to associate a deferred error with an I_T nexus and with a particular function or a particular subset of data, and the
error is either unrecovered or required to be reported by the mode parameters, then a deferred error indication shall be returned
for a command received on the I_T nexus associated with the deferred error. If an application client request received on an I_T
nexus other than the I_T nexus associated with the deferred error attempts to access the particular function or subset of data
associated with the deferred error and the TST field equals 000b, then the device server shall respond to the command with a
BUSY or ACA ACTIVE status according to the requirements in SAM-5. If an application client request received on an I_T nexus
other than the I_T nexus associated with the deferred error attempts to access the particular function or subset of data associated
with the deferred error and the TST field equals 001b, then the command attempting the access shall not be blocked by the
deferred error and the cause of the deferred error may result in an error being reported for the command attempting the access;

(c)

If the device server is unable to associate a deferred error with an I_T nexus or with a particular subset of data, the device server
shall return a deferred error for one command received on each I_T nexus. If multiple deferred errors have accumulated for an
I_T nexus, only the last error shall be returned;

(d)

If the SCSI target device is unable to associate a deferred error with a particular logical unit, it shall establish a deferred error for
every logical unit and shall return the deferred error for one command for each logical unit received on each appropriate I_T
nexus; or

(e)

If a task has never entered the enabled task state, and a deferred error occurs, the task shall be terminated with CHECK CONDITION status and deferred error information returned in the sense data. If a deferred error occurs after a task has entered the
enabled task state and the task is affected by the error, the task shall be terminated with CHECK CONDITION status and the current error information shall be returned in the sense data. In this case, if the current error information does not adequately define
the deferred error condition, a deferred error may be returned after the current error information has been returned. If a deferred
error occurs after a task has entered the enabled task state and the task completes successfully, the device server may choose to
return the deferred error information after the completion of the current command in conjunction with a subsequent command that
has not begun processing.

Note.

A deferred error may indicate that an operation was unsuccessful long after GOOD status was returned. If the application client is unable to replicate or recover from other sources the data that is being written using cached or buffered write operations, then synchronization commands should be performed before the critical data is destroyed. This is necessary for actions
taken when deferred errors occur in the storing of the data. The synchronizing process should provide the necessary commands to allow returning CHECK CONDITION status and subsequent returning of deferred error sense information after all
cached or buffered operations are completed.

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2.4.1.5

Sense key and sense code definitions

The sense keys are defined in table 28.
Table 28
Sense
Key

Sense key descriptions
Description

0h

NO SENSE: Indicates that there is no specific sense key information to be reported. This may occur for a successful command or for a command that receives CHECK CONDITION status because one of the FILEMARK, EOM, or
ILI bits is set to one.

1h

RECOVERED ERROR: Indicates that the command completed successfully, with some recovery action performed by the
device server. Details may be determined by examining the additional sense bytes and the INFORMATION field. When
multiple recovered errors occur during one command, the choice of which error to report (e.g., first, last, most severe) is
vendor specific.

2h

NOT READY: Indicates that the logical unit is not accessible. Operator intervention may be required to correct this condition.

3h

MEDIUM ERROR: Indicates that the command terminated with a non-recovered error condition that may have been
caused by a flaw in the medium or an error in the recorded data. This sense key may also be returned if the device server
is unable to distinguish between a flaw in the medium and a specific hardware failure (i.e., sense key 4h).

4h

HARDWARE ERROR: Indicates that the device server detected a non-recoverable hardware failure (e.g., controller failure,
device failure, or parity error) while performing the command or during a self test.

5h

ILLEGAL REQUEST: Indicates that:
a) The command was addressed to an incorrect logical unit number (see SAM-5);
b) The command had an invalid task attribute (see SAM-5);
c) The command was addressed to a logical unit whose current configuration prohibits processing the command;
d) There was an illegal parameter in the CDB; or
e) There was an illegal parameter in the additional parameters supplied as data for some commands (e.g.,
PERSISTENT RESERVE OUT).
If the device server detects an invalid parameter in the CDB, it shall terminate the command without altering the medium. If
the device server detects an invalid parameter in the additional parameters supplied as data, the device server may have
already altered the medium.

6h

UNIT ATTENTION: Indicates that a unit attention condition has been established (e.g., the removable medium may have
been changed, a logical unit reset occurred). See SAM-5.

7h

DATA PROTECT: Indicates that a command that reads or writes the medium was attempted on a block that is protected.
The read or write operation is not performed.

8h

BLANK CHECK: Indicates that a write-once device or a sequential-access device encountered blank medium or formatdefined end-of-data indication while reading or that a write-once device encountered a non-blank medium while writing.

9h

VENDOR SPECIFIC: This sense key is available for reporting vendor specific conditions.

Ah

COPY ABORTED: Indicates an EXTENDED COPY command was aborted due to an error condition on the source device,
the destination device, or both.

Bh

ABORTED COMMAND: Indicates that the device server aborted the command. The application client may be able to
recover by trying the command again.

Ch

Reserved

Dh

VOLUME OVERFLOW: Indicates that a buffered SCSI device has reached the end-of-partition and data may remain in the
buffer that has not been written to the medium. One or more RECOVER BUFFERED DATA command(s) may be issued to
read the unwritten data from the buffer. (See SSC-3.)

Eh

MISCOMPARE: Indicates that the source data did not match the data read from the medium.

Fh

COMPLETED: Indicates there is command completed sense data (see SAM-5) to be reported. This may occur for a successful command.

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2.4.1.6

Additional Sense and Additional Sense Qualifier codes

Table Note. lists the Additional Sense (ASC) and Additional Sense Qualifier (ASCQ) codes. Code values are in hexadecimal. ANSI
standard SPC-4 lists a more complete table in error description alphabetical order. This Table Note. list adequately covers all Seagate
drives, however.
Note.

Table Note. is for reference only, as not all drives covered by this manual support all of the codes listed. Codes without sense
key references may or may not be supported.

Table 29

Additional Sense and Additional Sense Qualifier codes
Description

Sense
Key

ASC
(byte 12)

ASCQ
(byte 13)

00

00

No Additional Sense Information

0

01

00

No Index/Logical Block Signal

4

02

00

No SEEK Complete

4

03

00

Peripheral Device Write Fault

03

86

Write Fault Data Corruption

04

00

Logical Unit Not Ready, Cause Not Reportable

2

04

01

Logical Unit Not Ready, Becoming Ready

2

04

02

Logical Unit Not Ready, START UNIT Required

2

04

03

Logical Unit Not Ready, Manual Intervention Required

2

04

04

Logical Unit Not Ready, Format in Progress

2

04

09

Logical Unit Not Ready, Self Test in Progress

2

04

0A

Logical Unit Not Ready, NVC recovery in progress after and exception event

2

04

11

Logical Unit Not Ready, Notify (Enable Spinup) required

2

04

F0

Logical unit not ready, super certify in progress

2

08

00

Logical Unit Communication Failure

08

01

Logical Unit Communication Time-Out

08

02

Logical Unit Communication Parity Error

09

00

Track Following Error

09

01

Servo Fault

1, 4

09

04

Head Select Fault

3, 4

09

0D

Write to at least one copy of a redundant file failed

1

09

0E

Redundant files have < 50% good copies

1

09

F8

Calibration is needed but the QST is set without the Recal Only bit

1

09

FF

Servo Cal completed as part of self-test

1

0A

00

Error Log Overflow

0A

01

Failed to write super certify log file

3

0A

02

Failed to read super certify log file

3

0B

00

Aborted Command

B

0B

01

Warning—Specified Temperature Exceeded

0B

02

Warning, Enclosure Degraded

SCSI Commands Reference Manual, Rev. H

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9, B
B

1, 3, 4

1, 6
1

31

Table 29

Additional Sense and Additional Sense Qualifier codes
Description

Sense
Key

ASC
(byte 12)

ASCQ
(byte 13)

0C

00

Write Error

3

0C

01

Write Error Recovered With Auto-Reallocation

1

0C

02

Write Error—Auto Reallocation Failed

3

0C

03

Write Error—Recommend Reassignment

3

0C

FF

Write Error—Too many error recovery revs

3

0D

00

Volume Overflow Constants

D

0E

00

Data Miscompare

E

10

00

ID CRC Or ECC Error

11

00

Unrecovered Read Error

11

01

Read Retries Exhausted

11

02

Error Too Long To Correct

11

04

Unrecovered Read Error—Auto Reallocation Failed

3

11

FF

Unrecovered Read Error—Too many error recovery revs

3

12

00

Address Mark Not Found For ID Field

12

01

Recovered Data Without ECC Using Previous Logical Block ID

12

02

Recovered Data With ECC Using Previous Logical Block ID

14

00

Logical Block Not Found

14

01

Record Not Found

15

00

Random Positioning Error

15

01

Mechanical Positioning Error

15

02

Positioning Error Detected By Read Of Medium

16

00

Data Synchronization Mark Error

17

00

Recovered Data With No Error Correction Applied

17

01

Recovered Data Using Retries

1

17

02

Recovered Data Using Positive Offset

1

17

03

Recovered Data Using Negative Offset

1

17

05

Recovered Data Using Previous Logical Block ID

17

06

Recovered Data Without ECC—Data Auto Reallocated

18

00

Recovered Data With ECC

1

18

01

Recovered Data With ECC And Retries Applied

1

18

02

Recovered Data With ECC And/Or Retries, Data Auto-Reallocated

1

18

05

Recovered Data—Recommand Reassignment

18

06

Recovered Data Using ECC and Offsets

18

07

Recovered Data With ECC—Data Rewritten

19

00

Defect List Error

SCSI Commands Reference Manual, Rev. H

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3

1, 3, 4

1, 3, 4

1
1, 4
32

Table 29

Additional Sense and Additional Sense Qualifier codes
Description

Sense
Key

ASC
(byte 12)

ASCQ
(byte 13)

19

01

Defect List Not Available

19

02

Defect List Error In Primary List

19

03

Defect List Error in Grown List

19

0E

Fewer than 50% Defect List Copies

1A

00

Parameter List Length Error

1B

00

Synchronous Data Transfer Error

1C

00

Defect List Not Found

1C

01

Primary Defect List Not Found

1C

02

Grown Defect List Not Found

1C

83

Seagate Unique Diagnostic Code

1D

00

Miscompare During Verify Operation

E

1F

00

Number of Defects Overflows the Allocated Space That The Read Defect Command
Can Handle

1

20

00

Invalid Command Operation Code

5

20

F3

Invalid linked command operation code

5

21

00

Logical Block Address Out Of Range

D

24

00

Invalid Field In CDB

5

24

01

Illegal Queue Type for CDB (Low priority commands must be SIMPLE queue)

5

24

F0

Invalid LBA in linked command

5

24

F2

Invalid linked command operation code

5

24

F3

Illegal G->P operation request

5

25

00

Logical Unit Not Supported

5

26

00

Invalid Field In Parameter List

5

26

01

Parameter Not Supported

5

26

02

Parameter Value Invalid

5

26

03

Invalid Field Parameter—Threshold Parameter

5

26

04

Invalid Release of Active Persistent Reserve

5

26

05

Fail to read valid log dump data

5

26

97

Invalid Field Parameter—TMS Firmware Tag

26

98

Invalid Field Parameter—Check Sum

26

99

Invalid Field Parameter—Firmware Tag

27

00

Write Protected

7

29

00

Flashing LED occurred

4

29

00

Power On, Reset, Or Bus Device Reset Occurred

6

29

01

Power-On Reset Occurred

6

29

02

SCSI Bus Reset Occurred

6

SCSI Commands Reference Manual, Rev. H

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1, 4

33

Table 29

Additional Sense and Additional Sense Qualifier codes
Description

Sense
Key

ASC
(byte 12)

ASCQ
(byte 13)

29

03

Bus Device Reset Function Occurred

6

29

04

Internal Reset Occurred

6

29

05

Transceiver Mode Changed To Single-Ended

6

29

06

Transceiver Mode Changed To LVD

6

29

07

Write Log Dump data to disk successful OR IT Nexus Loss

6

29

08

Write Log Dump data to disk fail

6

29

09

Write Log Dump Entry information fail

6

29

0A

Reserved disk space is full

6

29

0B

SDBP test service contained an error, examine status packet(s) for details

6

29

0C

SDBP incoming buffer overflow (incoming packet too big)

6

29

CD

Flashing LED occurred. (Cold reset)

6

29

CE

Flashing LED occurred. (Warm reset)

6

2A

01

Mode Parameters Changed

6

2A

02

Log Parameters Changed

6

2A

03

Reservations preempted

6

2A

04

Reservations Released

6

2A

05

Registrations Preempted

6

2C

00

Command Sequence Error

5

2F

00

Tagged Commands Cleared By Another Initiator

6

31

00

Medium Format Corrupted

3

31

01

Corruption in R/W format request

3

31

91

Corrupt World Wide Name (WWN) in drive information file

3

32

00

No Defect Spare Location Available

4

32

01

Defect List Update Error

32

02

No Spares Available—Too Many Defects On One Track

32

03

Defect list longer than allocated memory

3

33

00

Flash not ready for access

3

35

00

Unspecified Enclosure Services Failure

4

35

01

Unsupported Enclosure Function

5

35

02

Enclosure Services Unavailable

2

35

03

Enclosure Transfer Failure

4

35

04

Enclosure Transfer Refused

4

37

00

Parameter Rounded

1

3D

00

Invalid Bits In Identify Message

3E

03

Logical Unit Failed Self Test

SCSI Commands Reference Manual, Rev. H

3, 4, 5

4
34

Table 29

Additional Sense and Additional Sense Qualifier codes
Description

Sense
Key

ASC
(byte 12)

ASCQ
(byte 13)

3E

00

Logical Unit Has Not Self Configured Yet

3F

00

Target Operating Conditions Have Changed

6

3F

01

Device internal reset occurred

6

3F

02

Changed Operating Definition

6

3F

05

Device Identifier Changed

6

3F

0F

Echo buffer overwritten

B

3F

80

Buffer contents have changed

1

3F

90

Invalid APM Parameters

3F

91

World Wide Name (WWN) Mismatch

40

01

DRAM Parity Error

40

02

Spinup Error recovered with retries

1

42

00

Power-On Or Self-Test Failure

4

42

0A

Port A failed loopback test

4

42

0B

Port B failed loopback test

4

43

00

Message Reject Error

B

44

00

Internal Target Failure

1, 3, 4

44

F2

Data Integrity Check Failed on verify

4

44

F6

Data Integrity Check Failed during write

4

44

FF

XOR CDB check error

4

45

00

Select/Reselection Failure

B

47

00

SCSI Parity Error

B

47

03

Information Unit CRC Error

B

47

80

Fibre Channel Sequence Error

B

48

00

Initiator Detected Error Message Received

B

49

00

Invalid Message Received

B

4B

00

Data Phase Error

B

4B

01

Invalid transfer tag

B

4B

02

Too many write data

B

4B

03

ACK NAK Timeout

B

4B

04

NAK received

B

4B

05

Data Offset error

B

4B

06

Initiator response timeout

B

4C

00

Logical Unit Failed Self-Configuration

4E

00

Overlapped Commands Attempted

55

01

XOR Cache is Not Available

SCSI Commands Reference Manual, Rev. H

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1, 4

B

35

Table 29

Additional Sense and Additional Sense Qualifier codes
ASCQ
(byte 13)

55

04

PRKT table is full

5B1

00

Log Exception

5B*

01

Threshold Condition Met

5B*

02

Log Counter At Maximum

5B*

03

Log List Codes Exhausted

5C

00

RPL Status Change

5C

01

Spindles Synchronized

5C

02

Spindles Not Synchronized

5D

00

Failure Prediction Threshold Exceeded

1, 6

5D

FF

False Failure Prediction Threshold Exceeded

1, 6

65

00

Voltage Fault

4

80

00

General Firmware Error Qualifier

9

80

86

IOEDC Error on Read

9

80

87

IOEDC Error on Write

9

80

88

Host Parity Check Failed

9

80

89

IOEDC Error on Read Detected by Formatter

9

80

8A

Host FIFO Parity Error detected by Common Buffer

9

80

8B

Host FIFO Parity Error detected by frame buffer logic

9

80

8C

Host Data Frame Buffer Parity Error

9

81

00

Reassign Power—Fail Recovery Failed

81

00

LA Check Error, LCM bit = 0

4

81

00

LA Check Error

B

B4

00

Unreported Deferred Errors have been logged on log page 34h

6

[1]

Description

Sense
Key

ASC
(byte 12)

5

6

Can be supported, but is a factory installed option.

SCSI Commands Reference Manual, Rev. H

36

3.0

Command Reference

This clause describes the commands supported by Seagate Disk Drives.
Commands that have been supported prior to this manual being produced and that are now indicated as obsolete will be described in this
clause as obsolete. However, a description will be provided for such commands.
Commands that have been declared obsolete by the T10 committee and were never supported by Seagate are not included in this
manual. Commands that have not been supported in the past, but may be supported in the near future will be included in this manual.
This clause contains information about the commands used by Seagate Parallel SCSI, Fibre Channel, and Serial Attached SCSI disk
drives. This clause is organized to provide rapid access to command information.
Two types of commands are supported by the drive: commands for all devices; and commands for direct access devices. The individual
Product Manuals for each Seagate model drive list the Commands and parameter pages that the particular drive supports.
Commands sorted by command name

Command name

CHANGE DEFINITION

Command type

OP
code
[1]

All
devices

40h

x [2]

Direct
access
devices

Length
6
byte

10
byte

12
byte

16
byte

32
byte

x

clause
Reference
3.1

FORMAT UNIT

04h

x

GET LBA STATUS

9Eh

x

INQUIRY

12h

x

LOG SELECT

4Ch

x

LOG SENSE

4Dh

x

MODE SELECT (6)

15h

x

MODE SELECT (10)

55h

x

MODE SENSE (6)

1Ah

x

MODE SENSE (10)

5Ah

x

x

3.12

PERSISTENT RESERVE IN

5Eh

x

x

3.13

PERSISTENT RESERVE OUT

5Fh

x

x

3.14

READ (6)

3.5
x

3.6

x

3.6
x

3.7

x

3.8

x

3.9
x

3.10

x

08h

x

READ (10)

28h

x

READ (12)

A8h

x

READ (16)

88h

x

READ (32)

7Fh/0009h

x

READ BUFFER

3Ch

READ CAPACITY (10)

25h

x

READ CAPACITY (16)

9Eh/10h

x

37h

x

READ DEFECT DATA (12)

B7h

x

READ LONG (10)

3Eh

x

READ LONG (16)

9Eh/11h

x

REASSIGN BLOCKS

07h

x

RECEIVE DIAGNOSTIC RESULTS

1Ch

RELEASE (6)

17h

RELEASE (10)

57h

x [2]

A3h/05h

x

3.11

x

3.17
x

3.18
x

3.19
x

3.20
x

x

READ DEFECT DATA (10)

REPORT IDENTIFYING INFORMATION

x

3.21

x

3.22

x

3.23
x

x

3.24
3.25

x

3.26

x

3.27
x

3.28

x

3.29

x

x

3.30

x [2]

x

3.31
x

3.32
x

3.33

REPORT LUNS

A0h

x

REQUEST SENSE

03h

x

x

3.38

RESERVE (6)

16h

x [2]

x

3.39

RESERVE (10)

56h

x [2]

SCSI Commands Reference Manual, Rev. H

x

x

3.34

3.40
37

Command name

OP
code
[1]

Command type
All
devices

Length

Direct
access
devices

6
byte
x

10
byte

12
byte

16
byte

32
byte

clause
Reference

REZERO UNIT

01h

x [2]

SANITIZE

48H

x

SECURITY PROTOCOL IN

A2h

x

x

3.43

SECURITY PROTOCOL OUT

B5h

x

x

3.44

SEEK (6)

0Bh

x [2]

SEEK EXTENDED (10)

2Bh

x

SEND DIAGNOSTIC
SET IDENTIFYING INFORMATION

1Dh

x

A4h/06h

x

3.41
x

3.42

x

3.45
x

3.46

x

3.47
x

3.48

START/STOP UNIT

1Bh

x

SYNCHRONIZE CACHE (10)

35h

x

SYNCHRONIZE CACHE (16)

91h

TEST UNIT READY

00h

UNMAP

42h

x

x

3.54

VERIFY(10)

2Fh

x

x

3.55

VERIFY (12)

AFh

x

VERIFY (16)

8Fh

x

VERIFY (32)

7Fh/000Ah

x

WRITE (6)

x

2Ah

x

WRITE (12)

AAh

x

WRITE (16)

8Ah

x

WRITE (32)

7Fh/000Bh

x

WRITE AND VERIFY (10)

2Eh

x

WRITE AND VERIFY (12)

AEh

x

WRITE AND VERIFY (16)

8Eh

x

WRITE AND VERIFY (32)

7Fh/000Ch

x

WRITE BUFFER

3Bh

WRITE LONG

3Fh

x

WRITE LONG (16)

9Fh/11h

x

WRITE SAME (10)

41h

x

x

WRITE SAME (16)

93h

x

WRITE SAME (32)

7Fh/000Dh

x

3.1

x

3.51
x

3.52

x

0Ah

[2]

3.50

x
x

WRITE (10)

[1]

x

3.53

x

3.56
x

3.57
x

x

3.58
3.59

x

3.60
x

3.61
x

3.62
x

x

3.63
3.64

x

3.65
x

3.66
x

3.67

x

3.68

x

3.69
x

3.70

x

3.71
x

3.72
x

3.73

Some commands are defined by a combination of operation code and service action.
The operation code value is shown preceding the slash and the service action value is shown after the slash.
Command has been declared obsolete by the T10 committee. However, it is included because it may be implemented on some products.
CHANGE DEFINITION command

This command has been declared obsolete by the T10 committee. However, it is included because it may be implemented on some
products.

SCSI Commands Reference Manual, Rev. H

38

The CHANGE DEFINITION command (see table ) is used to modify the operating definition of the device server(s) with respect to
commands from the sending initiator or with respect to commands from all initiators.
Table 30

CHANGE DEFINITION command

Bit
Byte

7

6

5

4

3

0

OPERATION CODE (40h)

1

Reserved

2

2

1

Reserved

3

Reserved

0

SAVE

DEFINITION PARAMETER

4

Reserved

5

Reserved

6

Reserved

7

Reserved

8

PARAMETER DATA LENGTH

9

CONTROL

If reservations are active, they shall affect the execution of the CHANGE DEFINITION command as follows. If the SCSI device does not
allow different operating definitions for each initiator, a reservation conflict shall occur when a CHANGE DEFINITION command is received
from an initiator other than the one holding a logical unit reservation. If any initiator has an extent or element reservation on an SCSI
device, no other initiator may affect the operating definition of the initiator holding the reservation by use of the CHANGE DEFINITION
command.
A save control bit (SAVE) of zero indicates that the device server shall not save the operating definition. A Save bit of one indicates that the
device server shall save the operating definition in non-volatile memory.
The definition parameter field is defined in table 14.
Table 31

Definition parameter field

Value

Meaning of definition parameter

00h

Use current operating definition

03h

SCSI-2 operating definition

04h

SCSI-3 operating definition

01 - 02h

Reserved for historical uses

05 - 3Eh

Reserved

3Fh
40 - 7Fh

Manufacturer default definition
Vendor specific

The current operating definition parameter values establish operating definitions compatible with the applicable SCSI standard.
The parameter data length field specifies the length in bytes of the parameter data that shall be transferred from the application client to the
device server. A parameter data length of zero indicates that no data shall be transferred. This condition shall not be considered as an
error. Parameter data length values greater than zero indicate the number of bytes of parameter data that shall be transferred.
The parameter data is vendor-specific.
Note.

1 The parameter data may be used to specify a password to validate an operating definition change.

The CHANGE DEFINITION command causes one of the operating definition modifications listed below:
(a)

Change the operating definition of a logical unit relative to all initiators in the system: In this case, the target is capable of maintaining a separate operating definition for each logical unit relative to all initiators in the system; or

(b)

Change the operating definition of all logical units in the target relative to all initiators in the system: In this case, the target is capable of maintaining only one operating definition.

SCSI Commands Reference Manual, Rev. H

39

Note.

2 This manual does not provide a direct means to determine which of the above methods has been implemented. An indirect
means of determining which method is implemented exists in that the device server is required to inform affected initiators of
operating definition changes via the unit attention condition.

Note.

3 The modifications listed c) and d) above may result in incompatibilities if other initiators are using a different SCSI version.

The operating definition is modified after successful completion of the command. The application client should verify the new operating
definition by issuing an INQUIRY command requesting the implemented operating definition page (see 8.4.1 in SCSI -3).
4 The method of changing the operating definition is vendor-specific. Some implementations may require that the target’s
operating mode be reinitialized as if a power-up or hard reset had occurred. Other implementations may modify only those
operating definitions that are affected by the CHANGE DEFINITION command.

Note.

If the CHANGE DEFINITION command is not executed successfully for any reason, the operating definition shall remain the same as it
was before the CHANGE DEFINITION command was attempted. If it is impossible to return to the previous operating definition, a unit
attention condition shall be generated.
5 The present operating definition of the target may always be interrogated through the INQUIRY command. When an SCSI-3
target has its operating definition changed to an older SCSI operating definition, certain changes are needed to promote compatibility with preexisting older SCSI initiators.

Note.

After a power-on condition or a hard reset condition, the target shall set its initial operating definition of the device server(s) to the last
saved value (if saving is implemented), or its default value (if saving is not implemented).
3.2

COMPARE command

Obsolete. If received, a CHECK CONDITION status is sent.
3.3

COPY command

Obsolete. If received, a CHECK CONDITION status is sent.
3.4

COPY AND VERIFY command

Obsolete. If received, a CHECK CONDITION status is sent.
3.5

FORMAT UNIT command

3.5.1

FORMAT UNIT command overview

The FORMAT UNIT command (see table 32) requests that the device server format the medium into application client accessible logical
blocks as specified in the number of blocks and block length values received in the last mode parameter block descriptor (see 4.3.4) in a
MODE SELECT command (see 3.9and 3.10). In addition, the device server may certify the medium and create control structures for the
management of the medium and defects. The degree that the medium is altered by this command is vendor-specific.
If a device server receives a FORMAT UNIT command before receiving a MODE SELECT command with a mode parameter block
descriptor the device server shall use the number of blocks and block length at which the logical unit is currently formatted (i.e., no change
is made to the number of blocks and the block length of the logical unit during the format operation).
If any deferred downloaded code has been received as a result of a WRITE BUFFER command with the MODE field set to 0Eh (see 3.68),
then that deferred downloaded code shall replace the current operational code.
Table 32
Bit
Byte

FORMAT UNIT command
7

6

5

3

2

1

0

OPERATION CODE (04h)

0
1

4

FMTPINFO

LONG-LIST FMTDATA

2
3

CMPLIST

DEFECT LIST FORMAT

Vendor Specific
Obsolete

4
5

SCSI Commands Reference Manual, Rev. H

CONTROL

40

The simplest form of the FORMAT UNIT command (i.e., a FORMAT UNIT command with no parameter data) accomplishes medium
formatting with little application client control over defect management. The device server implementation determines the degree of defect
management that is to be performed. Additional forms of this command increase the application client's control over defect management.
The application client may specify:
a) defect list(s) to be used;
b) defect locations;
c) that logical unit certification be enabled; and
d) exception handling in the event that defect lists are not accessible.
While performing a format operation, the device server shall respond to commands attempting to enter into the task set except INQUIRY
commands, REPORT LUNS commands, and REQUEST SENSE commands with CHECK CONDITION status with the sense key set to
NOT READY and the additional sense code set to LOGICAL UNIT NOT READY, FORMAT IN PROGRESS. Handling of commands
already in the task set is vendor-specific. If the device server receives an INQUIRY command, a REPORT LUNS commands, or a
REQUEST SENSE command, then the device server shall process the command. The device server shall return data for an INQUIRY
command based on the condition of the SCSI target device before beginning the FORMAT UNIT command (i.e., INQUIRY data shall not
change until after successful completion of a format operation). The processing of commands in the task set when a FORMAT UNIT
command is received is vendor specific.
FMTPINFO (Format Protection Information) field
The format protection information (FMTPINFO) field (see table 37) in combination with the PROTECTION FIELD USAGE field (see 3.5.3)
specifies whether or not the device server enables or disables the use of protection information.
When protection information is written during a FORMAT UNIT command (i.e., the FMTPINFO bit is set to one) protection information shall
be written to a default value of FFFFFFFF_FFFFFFFFh.
LONGLIST bit
If the FMTDATA bit is set to zero, the LONGLIST bit shall be ignored.
0

A LONGLIST bit set to zero specifies that the parameter list, if any, contains a short parameter list header as defined in table 35.

1

A LONGLIST bit set to one specifies that the parameter list, if any, contains a long parameter list header as defined in table 36.

FMTDATA (Format Data)
0

A format data (FMTDATA) bit set to zero specifies that no parameter list be transferred from the data-out buffer.

1

A FMTDATA bit set to one specifies that the FORMAT UNIT parameter list (see table 34) shall be transferred from the data-out buffer. The parameter list consists of a parameter list header, followed by an optional initialization pattern descriptor, followed by an
optional defect list.

CMPLST (Complete List)
If the FMTDATA bit is set to zero, the CMPLIST bit shall be ignored.
0

A complete list (CMPLST) bit set to zero specifies that the defect list included in the FORMAT UNIT parameter list shall be used in
an addition to the existing list of defects. As a result, the device server shall construct a new GLIST that contains:
a) the existing GLIST;
b) the DLIST, if it is sent by the application client; and
c) the CLIST, if certification is enabled (i.e., the device server may add any defects it detects during the format operation).

1

A CMPLST bit set to one specifies that the defect list included in the FORMAT UNIT parameter list is a complete list of defects. Any
existing GLIST shall be discarded by the device server. As a result, the device server shall construct a new GLIST that contains:
a) the DLIST, if it is sent by the application client; and
b) the CLIST, if certification is enabled (i.e., the device server may add any defects it detects during the format operation).

DEFECT LIST FORMAT field
The DEFECT LIST FORMAT field specifies the format of the address descriptors in the defect list if the FMTDATA bit is set to one (see
table 33).

SCSI Commands Reference Manual, Rev. H

41

Table 33 defines the address descriptor usage for the FORMAT UNIT command.
Table 33

FORMAT UNIT command address descriptor usage

Field in the FORMAT UNIT CDB
FMTDATA

CMPLST

DEFECT LIST
FORMAT

0

Any

000b

DEFECT LIST LENGTH
field in the parameter Type [a]
list header
Not available

0
1

1
0

Zero
000b
(short block)
Nonzero

1
0
1

1
0

Zero
001b
(long block)
Nonzero

1
0
1

1
0

Zero
010b
(long block)
Nonzero

1
0
1

1
0

Zero
011b
(long block)
Nonzero

1
0
1

1
0

Zero

100b
(bytes from
index)

Nonzero

1
0
1

1
0

Zero

101b
(physical
sector)

Nonzero

1
1

0
1

110b
(vendor
specific)

Vendor specific

All others

Comments [f]

M

Vendor-specific defect information

O

See [b] and [d]

O

See [b] and [e]

O

See [c] and [d]

O

See [c] and [e]

O

See [b] and [d]

O

See [b] and [e]

O

See [c] and [d]

O

See [c] and [e]

O

See [b] and [d]

O

See [b] and [e]

O

See [c] and [d]

O

See [c] and [e]

O

See [b] and [d]

O

See [b] and [e]

O

See [c] and [d]

O

See [c] and [e]

O

See [b] and [d]

O

See [b] and [e]

O

See [c] and [d]

O

See [c] and [e]

O

See [b] and [d]

O

See [b] and [e]

O

See [c] and [d]

O

See [c] and [e]

O
O
Reserved.

[a]

M = implementation is mandatory. O = implementation is optional.

[b]

No DLIST is included in the parameter list.

[c]

A DLIST is included in the parameter list. The device server shall add the DLIST defects to the new GLIST.

[d]

The device server shall add existing GLIST defects to the new GLIST (i.e., use the existing GLIST).

[e]

The device server shall not add existing GLIST defects to the new GLIST (i.e., discard the existing GLIST).

[f]

All the options described in this table cause a new GLIST to be created during processing of the FORMAT UNIT
command as described in the text.

SCSI Commands Reference Manual, Rev. H

42

3.5.2

FORMAT UNIT parameter list

3.5.2.1

FORMAT UNIT parameter list overview

Table 34 defines the FORMAT UNIT parameter list.
Table 34
Bit
Byte

FORMAT UNIT parameter list
7

6

5

4

3

2

1

0

Parameter List Header (see table 35 or table 36 in 3.5.3)

Initialization Pattern Descriptor (if any) (see table 38, in 3.5.4)

Defect List (if any)

PARAMETER LIST HEADER field
The PARAMETER LIST HEADER is defined in 3.5.3.
INITIALIZATION PATTERN DESCRIPTOR field
The INITIALIZATION PATTERN DESCRIPTOR, if any, is defined in 3.5.4.
DEFECT LIST field
The DEFECT LIST, if any, contains address descriptors (see table 33) each specifying a location on the medium that the device server
shall exclude from the application client accessible part. This is called the DLIST.

SCSI Commands Reference Manual, Rev. H

43

3.5.3

Parameter list header

The parameter list headers (see table 35 and table 36) provide several optional format control parameters. Device servers that implement
these headers provide the application client additional control over the use of the four defect sources, and the format operation. If the
application client attempts to select any function not implemented by the device server, the device server shall terminate the command with
CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN
PARAMETER LIST.
The short parameter list header (see table 35) is used if the LONGLIST bit is set to zero in the FORMAT UNIT CDB.
Table 35
Bit
Byte

Short parameter list header
7

6

5

4

3

2

Reserved

0
1

FOV

2

(MSB)

DPRY

DCRT

1

0

PROTECTION FIELDS USAGE
STPF

IP

Obsolete

IMMED

Vendor specific

DEFECT LIST LENGTH
(LSB)

3

The long parameter list header (see table 36) is used if the LONGLIST bit is set to one in the FORMAT UNIT CDB.
Table 36
Bit
Byte

Long parameter list header
7

6

FOV

DPRY

DCRT

3

2

1

0

PROTECTION FIELDS USAGE
STPF

IP

Obsolete

IMMED

Vendor specific

Reserved

2
P_I_INFORMATION

3
4

4

Reserved

0
1

5

PROTECTION INTERVAL EXPONENT

(MSB)

...
7

DEFECT LIST LENGTH
(LSB)

The PROTECTION FIELD USAGE field in combination with the FMTPINFO field (see table 37) specifies the requested protection type
(see SBC-3).

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Table 37

FMTPINFO field and PROTECTION FIELDS USAGE field

Device server indication

Application client specification

PROTECT [b]

FMTPINFO

PROTECTION
FIELD USAGE

Description

SPT [a]
xxxb

0

00b

000b

The logical unit shall be formatted to type 0 protection [c] (see SBC-3)
resulting in the P_TYPE field [d] being set to 000b.

xxxb

0

00b

>000b

Illegal [e]

xxxb

0

01b

xxxb

Illegal [f]

xxxb

0

1xb

xxxb

Illegal [f]

xxxb

1

00b

000b

The logical unit shall be formatted to type 0 protection [c] (see SBC-3)
resulting in the P_TYPE field [d] being set to 000b.

xxxb

1

00b

>000b

Illegal [e]

xxxb

1

0b

xxxb

Illegal [f]

000b
001b
011b
111b

1

000b
001b
011b
111b

1

000b

1

000b
001b
011b
111b

1

001b
010b

1

011b
100b

1

011b
100b
101b
111b

1

011b
100b
101b
111b
110b

The logical unit shall be formatted to type 1 protection [g] (see SBC-3)
resulting in the P_TYPE field [d] being set to 000b.

10b

000b

10b

>000b

Illegal [e]

11b

xxxb

Illegal [f]

11b

000b

11b

>000b

11b

000b

The logical unit shall be formatted to type 2 protection [g] (see SBC-3)
resulting in the P_TYPE field [d] being set to 001b.

Illegal [e]
Illegal [e]
The logical unit shall be formatted to type 3 protection.[g] (see SBC-3)
resulting in the P_TYPE field [d] being set to 010b.

11b

001b

1

11b

>001b

Illegal [e]

1

1xb

xxxb

Reserved

[a]

See the Extended INQUIRY Data VPD page(see 4.4.7) for the definition of the spt field.

[b]

See the standard INQUIRY data(see 3.6.2) for the definition of the protect bit.

[c]

The device server shall format the medium to the block length specified in the mode parameter block descriptor of the mode
parameter header (see 4.3.3).

[d]

See the READ CAPACITY command (see 3.23.1) for the definition of the P_TYPE field.

[e]

The device server shall terminate the command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST
and the additional sense code set to INVALID FIELD IN PARAMETER LIST.

[f]

The device server shall terminate the command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST
and the additional sense code set to INVALID FIELD IN CDB.

[g]

The device server shall format the medium to the block length specified in the mode parameter block descriptor of the mode
parameter header plus eight (e.g., if the block length is 512, then the formatted block length is 520). Following a successful format,
the prot_en bit in the READ CAPACITY (16) parameter data (see 3.24.1) indicates whether protection information (see SBC-3) is
enabled.

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FOV (Format Options Valid) bit
0

A format options valid (FOV) bit set to zero specifies that the device server shall use its default settings for the DPRY, DCRT, STPF,
and IP bits. If the FOV bit is set to zero, the application client shall set these bits to zero. If the FOV bit is set to zero and any of the
other bits listed in this paragraph are not set to zero, the device server shall terminate the command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN PARAMETER LIST.

1

A FOV bit set to one specifies that the device server shall examine the values of the DPRY, DCRT, STPF, and IP bits. When the
FOV bit is set to one, the DPRY, DCRT, STPF, and IP bits are defined as follows.

DPRY (Disable Primary) bit
0

A disable primary (DPRY) bit set to zero specifies that the device server shall not use parts of the medium identified as defective in
the PLIST for application client accessible logical blocks. If the device server is not able to locate the PLIST or it is not able to determine whether a PLIST exists, it shall take the action specified by the STPF bit.

1

A DPRY bit set to one specifies that the device server shall not use the PLIST to identify defective areas of the MEDIUM. The
PLIST shall not be deleted.

DCRT (disable certification) bit
0

A disable certification (DCRT) bit set to zero specifies that the device server shall perform a vendor-specific medium certification
operation to generate a CLIST.

1

A DCRT bit set to one specifies that the device server shall not perform any vendor-specific medium certification process or format
verification operation.

STPF (Stop Format) bit
The stop format (STPF) bit controls the behavior of the device server if one of the following events occurs:
a) The device server has been requested to use the PLIST (i.e., the DPRY bit is set to zero) or the GLIST (i.e., the CMPLST bit
is set to zero) and the device server is not able to locate the list or determine whether the list exists; or
b) The device server has been requested to use the PLIST (i.e., the DPRY bit is set to zero) or the GLIST (i.e., the CMPLST bit
is set to zero), and the device server encounters an error while accessing the defect list.
0

A STPF bit set to zero specifies that, if one or both of these events occurs, the device server shall continue to process the FORMAT
UNIT command. The device server shall return CHECK CONDITION status at the completion of the FORMAT UNIT command with
the sense key set to RECOVERED ERROR and the additional sense code set to either DEFECT LIST NOT FOUND if the condition
described in item a) occurred, or DEFECT LIST ERROR if the condition described in item b) occurred.

1

A STPF bit set to one specifies that, if one or both of these events occurs, the device server shall terminate the FORMAT UNIT
command with CHECK CONDITION status and the sense key shall be set to MEDIUM ERROR with the additional sense code set
to either DEFECT LIST NOT FOUND if the condition described in item a) occurred, or DEFECT LIST ERROR if the condition
described in item b) occurred.

Note.

The use of the FMTDATA bit, the CMPLST bit, and the parameter list header allow the application client to control the source
of the defect lists used by the FORMAT UNIT command. Setting the DEFECT LIST LENGTH field to zero allows the application client to control the use of PLIST and CLIST without having to specify a DLIST.

IP (initialization pattern) bit
0

An initialization pattern (IP) bit set to zero specifies that an initialization pattern descriptor is not included and that the device server
shall use its default initialization pattern.

1

An IP bit set to one specifies that an initialization pattern descriptor (see 3.5.4) is included in the FORMAT UNIT parameter list following the parameter list header.

IMMED (Immediate) bit
0

An immediate (IMMED) bit set to zero specifies that the device server shall return status after the format operation has completed.

1

An IMMED bit value set to one specifies that the device server shall return status after the entire parameter list has been transferred.

P_I_INFORMATION field
The P_I_INFORMATION field shall be set to zero.
PROTECTION INTERVAL EXPONENT field
For a type 1 protection information request, if the PROTECTION INTERVAL EXPONENT field is not set to zero, then the device server
shall terminate the command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense
code set to INVALID FIELD IN PARAMETER LIST.
For a type 2 protection or a type 3 protection format request, the protection interval exponent determines the length of user data to be sent
before protection information is transferred (i.e., the protection information interval).
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The protection information interval is calculated as follows:
protection information interval = logical block length / 2(protection interval exponent)
where:
logical block length

is the length in bytes of a logical block as specified in the mode parameter block descriptor (see
clause 4.3.4.1)

protection interval exponent

is the contents of the PROTECTION INTERVAL EXPONENT field

If the protection information interval calculates to a value that is not an even number (e.g., 520/23 = 65) or not a whole number (e.g., 520/
24 = 32.5 and 520/210 = 0.508), then the device server shall terminate the command with CHECK CONDITION status with the sense key
set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN PARAMETER LIST.
DEFECT LIST LENGTH field
The DEFECT LIST LENGTH field specifies the total length in bytes of the defect list (i.e., the address descriptors) that follows and does not
include the initialization pattern descriptor, if any. The formats for the address descriptor(s) are shown in table 41.
Address descriptors should be in ascending order. More than one physical or logical block may be affected by each address descriptor. If
the address descriptors are not in the required order, the device server shall terminate the command with CHECK CONDITION status with
the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN PARAMETER LIST.
3.5.4

Initialization pattern descriptor

The initialization pattern descriptor specifies that the device server initialize logical blocks to a specified pattern. The initialization pattern
descriptor (see table 38) is sent to the device server as part of the FORMAT UNIT parameter list.
Table 38
Bit
Byte
0

Initialization pattern descriptor
6

5

IP MODIFIER

SI

7

3

2

1

0

Reserved
INITIALIZATION PATTERN TYPE

1
2

4

(MSB)

3

INITIALIZATION PATTERN LENGTH (N - 3)

(LSB)

4
INITIALIZATION PATTERN

...
N
IP MODIFIER (Initilization Pattern Modifier) field

The IP MODIFIER field is obsolete in SBC-3 but is included here because it may be implemented in older products.
The initialization pattern modifier (IP MODIFIER) field (see table 39) specifies the type and location of a header that modifies the initialization pattern.
Table 39
Code

Initialization pattern modifier (IP MODIFIER) field
Description

00b

No header. The device server shall not modify the initialization pattern.

01b

The device server shall overwrite the initialization pattern to write the LBA in the first four bytes of each logical
block. The LBA shall be written with the most significant byte first. If the LBA is larger than four bytes, the least
significant four bytes shall be written ending with the least significant byte.

10b

The device server shall overwrite the initialization pattern to write the LBA in the first four bytes of each physical block contained within the logical block. The lowest numbered logical block or part thereof that occurs
within the physical block is used. The LBA shall be written with the most significant byte first. If the LBA is
larger than four bytes the least significant four bytes shall be written ending with the least significant byte.

11b

Reserved.

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SI (Security Initialize) bit
A security initialize (SI) bit set to one specifies that the device server shall attempt to write the initialization pattern to all areas of the
medium including those that may have been reassigned (i.e., are in a defect list). An SI bit set to one shall take precedence over any other
FORMAT UNIT CDB field. The initialization pattern shall be written using a security erasure write technique. Application clients may
choose to use this command multiple times to fully erase the previous data. Such security erasure write technique procedures are outside
the scope of this manual. The exact requirements placed on the security erasure write technique are vendor-specific. The intent of the
security erasure write is to render any previous user data unrecoverable by any analog or digital technique.
0

An SI bit set to zero specifies that the device server shall initialize the application client accessible part of the medium. The device
server is not required to initialize other areas of the medium. However, the device server shall format the medium as defined in the
FORMAT UNIT command.

1

When the SI bit is set to one, the device server need not write the initialization pattern over the header and other header and other
parts of the medium not previously accessible to the application client. If the device server is unable to write over any part of the
medium that is currently accessible to the application client or may be made accessible to the application client in the future (e.g.,
by clearing the defect list), it shall terminate the command with CHECK CONDITION status with the sense key set to MEDIUM
ERROR and the additional sense code set to the appropriate value for the condition. The device server shall attempt to rewrite all
remaining parts of the medium even if some parts are not able to be rewritten.

INITIALIZATION PATTERN TYPE field
The INITIALIZATION PATTERN TYPE field (see table 40) specifies the type of pattern the device server shall use to initialize each logical
block within the application client accessible part of the medium. All bytes within a logical block shall be written with the initialization pattern. The initialization pattern is modified by the IP MODIFIER field as described in table 39.
INITIALIZATION PATTERN TYPE field

Table 40
Code

Description
00h

Use a default initialization pattern [a]

01h

Repeat the pattern specified in the INITIALIZATION PATTERN field as required to fill the logical block [b]

02h - 7Fh

Reserved

80h - FFh

Vendor-specific

[a]

If the INITIALIZATION PATTERN LENGTH field is not set to zero, the device server shall terminate the command with
CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID
FIELD IN PARAMETER LIST.

[b]

If the INITIALIZATION PATTERN LENGTH field is set to zero, the device server shall terminate the command with CHECK
CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN
PARAMETER LIST.

INITIALIZATION PATTERN LENGTH field
The INITIALIZATION PATTERN LENGTH field specifies the number of bytes contained in the INITIALIZATION PATTERN field. If the initialization pattern length exceeds the current block length the device server shall terminate the command with CHECK CONDITION status
with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN PARAMETER LIST.
INITIALIZATION PATTERN field
The INITIALIZATION PATTERN field specifies the initialization pattern. The initialization pattern is modified by the IP MODIFIER field.
3.5.5
3.5.5.1

Address descriptor formats
Address descriptor formats overview

This subclause describes the address descriptor formats used in the FORMAT UNIT command, the READ DEFECT DATA commands
(see 3.25 and 3.26), and the Translate Address diagnostic pages (see 4.1.3) of the SEND DIAGNOSTIC command and the RECEIVE
DIAGNOSTIC RESULTS command.
The format type of an address descriptor is specified with:
a) the DEFECT LIST FORMAT field in the CDB, for the FORMAT UNIT command and the READ DEFECT DATA commands;
b) the SUPPLIED FORMAT field, for the SEND DIAGNOSTIC command Translate Address diagnostic page; or
c) the TRANSLATE FORMAT field, for the RECEIVE DIAGNOSTIC RESULTS command Translate Address diagnostic page.

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Table 41 defines the types of address descriptors.
Table 41

Address descriptor formats

Format type

Description

000b

Short block format address descriptor

3.5.5.2

001b

Extended bytes from index address descriptor [a]

3.5.5.3

010b

Extended physical sector address descriptor [a]

3.5.5.4

011b

Long block format address descriptor

3.5.5.5

100b

Bytes from index format address descriptor

3.5.5.6

101b

Physical sector format address descriptor

3.5.5.7

110b

Vendor-specific
Reserved

All others
[a]

Reference

This address descriptor format type is defined for direct access block devices
using rotating media (see SBC-3).

3.5.5.2

Short block format address descriptor

A format type of 000b specifies the short block format address descriptor defined in table 42.
Table 42

Short block format address descriptor (000b)

Bit
Byte

7

0

(MSB)

6

...
3

5

4

3

2

1

0

SHORT BLOCK ADDRESS
(LSB)

SHORT BLOCK ADDRESS field
For the FORMAT UNIT command, the SHORT BLOCK ADDRESS field contains the four-byte LBA of a defect. For the READ DEFECT
DATA commands, the SHORT BLOCK ADDRESS field contains a vendor-specific four-byte value. For the Translate Address diagnostic
pages, the SHORT BLOCK ADDRESS field contains a four-byte LBA or a vendor-specific four byte value that is greater than the capacity
of the medium.

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3.5.5.3

Extended bytes from index address descriptor

A format type of 001b specifies the extended bytes from index address descriptor defined in table 43. For the FORMAT UNIT command
and the READ DEFECT DATA command, this descriptor specifies the location of a defect that is either:
a. the length of one track;
b. is less than the length of a physical block; or
c. a defect that starts from one address descriptor and extends to the next address descriptor.
For the Translate Address diagnostic pages, this descriptor specifies the location of an LBA. If format type 001b is used in the SUPPLIED
FORMAT field of a Translate Address Output diagnostic page (see 4.1.4), and the MADS bit in the ADDRESS TO TRANSLATE field is set
to one, then the device server shall terminate the SEND DIAGNOSTIC command with CHECK CONDITION status with the sense key set
to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN PARAMETER LIST.

Table 43

Bytes from index format address descriptor (100b)

Bit
Byte

7

0

(MSB)

6

5

4

3

1

0

CYLINDER NUMBER

...

(LSB)

2
HEAD NUMBER

3
4

2

MADS

Reserved

...
7

(MSB)

BYTES FROM INDEX

(LSB)

CYLINDER NUMBER field
The CYLINDER NUMBER field contains the cylinder number.
HEAD NUMBER field
The HEAD NUMBER field contains the head number.
MADS bit
A multi-address descriptor start (MADS) bit set to one specifies that this descriptor defines the beginning of a defect that spans multiple
address descriptors. The defect may be a number of sequential physical blocks on the same cylinder and head (i.e., a track) or may be a
number of sequential tracks on the same head. A MADS bit set to zero specifies that:
a) this descriptor defines the end of a defect if the previous address descriptor has the MADS bit set to one; or
b) this descriptor defines a single defective physical track (i.e., the BYTES FROM INDEX field contains FFF_FFFFh) or a single defective
physical block (i.e., the BYTES FROM INDEX field does not contain FFF_FFFFh).
See SBC-3 for valid combinations of two address descriptors that describe a defect.
BYTES FROM INDEX field
a) if not set to FFF_FFFFh, contains the number of bytes from the index (e.g., from the start of the track) to the location being described; or
b) if set to FFF_FFFFh, specifies that the entire track is being described.
For sorting bytes from index format address descriptors, the cylinder number is the most significant part of the address and the bytes from
index is the least significant part of the address. More than one logical block may be described by this descriptor.

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3.5.5.4

Extended physical sector address descriptor

A format type of 010b specifies the extended physical sector address descriptor defined in table 44. For the FORMAT UNIT command and
the READ DEFECT DATA command, this descriptor specifies the location of a defect that is either:
a) the length of one track;
b) is less than the length of a physical block; or
c) a defect that starts from one address descriptor and extends to the next address descriptor.
For the Translate Address diagnostic pages, this descriptor specifies the location of an LBA. If format type 010b is used in the SUPPLIED
FORMAT field of a Translate Address Output diagnostic page (see 4.1.4), and the MADS bit in the ADDRESS TO TRANSLATE field is set
to one, then the device server shall terminate the SEND DIAGNOSTIC command with CHECK CONDITION status with the sense key set
to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN PARAMETER LIST.

Table 44

Bytes from index format address descriptor (100b)

Bit
Byte

7

0

(MSB)

6

5

4

3

2

1

CYLINDER NUMBER

...

(LSB)

2
HEAD NUMBER

3
4

0

MADS

Reserved

...
7

(MSB)

SECTOR NUMBER

(LSB)

CYLINDER NUMBER field
The CYLINDER NUMBER field contains the cylinder number.
HEAD NUMBER field
The HEAD NUMBER field contains the head number.
MADS bit
A multi-address descriptor start (MADS) bit set to one specifies that this descriptor defines the beginning of a defect that spans multiple
address descriptors. The defect may be a number of sequential physical blocks on the same cylinder and head (i.e., a track) or may be a
number of sequential tracks on the same head. A MADS bit set to zero specifies that:
a) this descriptor defines the end of a defect if the previous address descriptor has the MADS bit set to one; or
b) this descriptor defines a single defective physical track (i.e., the BYTES FROM INDEX field contains FFF_FFFFh) or a single defective
physical block (i.e., the BYTES FROM INDEX field does not contain FFF_FFFFh).
See SBC-3 for valid combinations of two address descriptors that describe a defect.
The SECTOR NUMBER field contains the sector number. A SECTOR NUMBER field set to FFF_FFFFh specifies that the entire track is
being described.
SECTOR NUMBER field
a) if not set to FFF_FFFFh, contains the sector number of the location being described; or
b) if set to FFF_FFFFh, specifies that the entire track is being described.
For sorting extended physical sector address descriptors, the cylinder number is the most significant part of the address and the sector
number is the least significant part of the address. More than one logical block may be described by this descriptor.

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3.5.5.5

Long block format address descriptor

A format type of 011b specifies the long block format address descriptor defined in table 45.
Table 45

Long block format address descriptor (011b)

Bit
Byte

7

0

(MSB)

6

5

4

3

2

1

0

LONG BLOCK ADDRESS

...

(LSB)

7
LONG BLOCK ADDRESS field

For the FORMAT UNIT command, the LONG BLOCK ADDRESS field contains the eight-byte logical block address of a defect. If multiple
logical blocks are contained within a physical block, then the device server may consider logical blocks in addition to the one specified by
this descriptor as containing defects. For the READ DEFECT DATA commands, the LONG BLOCK ADDRESS field contains a vendor-specific eight-byte value. For the Translate Address diagnostic pages, the LONG BLOCK ADDRESS field contains a four-byte LBA or a vendor-specific four byte value that is greater than the capacity of the medium.
3.5.5.6

Bytes from index format address descriptor

A format type of 100b specifies the bytes from index address descriptor defined in table 46. For the FORMAT UNIT command and the
READ DEFECT DATA commands, this descriptor specifies the location of a defect that is either the length of one track or is no more than
eight bytes long. For the Translate Address diagnostic pages, this descriptor specifies the location of a track or the first byte or last byte of
an area
.
Table 46

Bytes from index format address descriptor (100b)

Bit
Byte

7

0

(MSB)

6

5

4

3

1

0

CYLINDER NUMBER

...

(LSB)

2
HEAD NUMBER

3
4

2

(MSB)

...

BYTES FROM INDEX

7

(LSB)

CYLINDER NUMBER field
The CYLINDER NUMBER field contains the cylinder number.
HEAD NUMBER field
The HEAD NUMBER field contains the head number.
BYTES FROM INDEX field
The BYTES FROM INDEX field contains the number of bytes from the index (e.g., from the start of the track) to the location being
described. A BYTES FROM INDEX field set to FFFFFFFFh specifies that the entire track is being described.
For sorting bytes from index format address descriptors, the cylinder number is the most significant part of the address and the bytes from
index is the least significant part of the address. More than one logical block may be described by this descriptor.

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3.5.5.7

Physical sector format address descriptor

A format type of 101b specifies the physical sector address descriptor defined in table 47. For the FORMAT UNIT command and the READ
DEFECT DATA commands, this descriptor specifies the location of a defect that is either the length of one track or the length of one sector.
For the Translate Address diagnostic pages, this descriptor specifies the location of a track or a sector.
Table 47

Physical sector format address descriptor (101b)

Bit
Byte

7

0

(MSB)

6

5

4

3

1

0

CYLINDER NUMBER

...

(LSB)

2
HEAD NUMBER

3
4

2

(MSB)

...

SECTOR NUMBER

7

(LSB)

CYLINDER NUMBER field
The CYLINDER NUMBER field contains the cylinder number.
HEAD NUMBER field
The HEAD NUMBER field contains the head number.
SECTOR NUMBER field
The SECTOR NUMBER field contains the sector number. A SECTOR NUMBER field set to FFFFFFFFh specifies that the entire track is
being described.
For sorting physical sector format address descriptors, the cylinder number is the most significant part of the address and the sector
number is the least significant part of the address. More than one logical block may be described by this descriptor.

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3.6

INQUIRY command

3.6.1

INQUIRY command introduction

The INQUIRY command (see table 48) requests that information regarding the logical unit and SCSI target device be sent to the
application client.
Table 48
Bit
Byte

INQUIRY command
7

6

4

3

2

1

0

Obsolete
Formerly
CMDDT

EVPD

OPERATION CODE (12h)

0

Reserved

1

PAGE CODE

2
3

5

(MSB)

4

ALLOCATION LENGTH

(LSB)

CONTROL

5
EVPD (Enable Vital Product Data) bit

An enable vital product data (EVPD) bit set to one specifies that the device server shall return the vital product data specified by the PAGE
CODE field (see 3.6.4).
0

If the EVPD bit is set to zero, the device server shall return the standard INQUIRY data (see 3.6.2). If the PAGE CODE field is not
set to zero when the EVPD bit is set to zero, the command shall be terminated with CHECK CONDITION status, with the sense key
set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN CDB.

1

When the EVPD bit is set to one, the PAGE CODE field specifies which page of vital product data information the device server
shall return (see 4.4).

CMDDT (Command Support Data) bit
This bit has been declared obsolete by the T10 committee. However, it is included because it may be implemented on some products.See
SPC-2 for a description of this bit.
If both the EVPD and CMDDT bits are one, the target shall return CHECK CONDITION status with the sense key set to ILLEGAL
REQUEST and an additional sense code of Invalid Field in CDB. When the EVPD bit is one, the Page or OPERATION CODE field specifies which page of vital product data information the target shall return.
ALLOCATION LENGTH field
The ALLOCATION LENGTH field is defined in 2.2.6. If EVPD is set to zero, the allocation length should be at least five, so that the ADDITIONAL LENGTH field in the parameter data (see 3.6.2) is returned. If EVPD is set to one, the allocation length should be should be at
least four, so that the PAGE LENGTH field in the parameter data (see 4.4) is returned.
In response to an INQUIRY command received by an incorrect logical unit, the SCSI target device shall return the INQUIRY data with the
peripheral qualifier set to the value defined in 3.6.2. The INQUIRY command shall return CHECK CONDITION status only when the device
server is unable to return the requested INQUIRY data.
If an INQUIRY command is received from an initiator port with a pending unit attention condition (i.e., before the device server reports
CHECK CONDITION status), the device server shall perform the INQUIRY command and shall not clear the unit attention condition (see
SAM-5).
The INQUIRY data should be returned even though the device server is not ready for other commands. The standard INQUIRY data
should be available without incurring any media access delays. If the device server does store some of the standard INQUIRY data or VPD
data on the media, it may return ASCII spaces (20h) in ASCII fields and zeros in other fields until the data is available from the media.
The INQUIRY data may change as the SCSI target device and its logical units perform their initialization sequence. (E.g., logical units may
provide a minimum command set from nonvolatile memory until they load the final firmware from the media. After the firmware has been
loaded, more options may be supported and therefore different INQUIRY data may be returned.)
If the INQUIRY data changes for any reason, the device server shall establish a unit attention condition for the initiator port associated with
every I_T nexus (see SAM-5), with the additional sense code set to INQUIRY DATA HAS CHANGED.
The INQUIRY command may be used by an application client after a hard reset or power on condition to determine the device types for
system configuration.

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3.6.2

Standard INQUIRY data

The standard INQUIRY data (see table 49) shall contain at least 36 bytes
Table 49
Bit
Byte
0
1

Standard INQUIRY data format
7

6

5

4

PERIPHERAL QUALIFIER

2

1

0

PERIPHERAL DEVICE TYPE

RMB

Reserved
VERSION

2
3

3

Obsolete

Obsolete

NORMACA

HISUP

RESPONSE DATA FORMAT

ADDITIONAL LENGTH (N-4)

4
5

SCCS

ACC

TPGS

3PC

Reserved

6

Obsolete

ENCSERV

VS

MULTIP

Obsolete

Obsolete

Obsolete

ADDR16 [a]

7

Obsolete

Obsolete

WBUS16 [a]

SYNC [a]

Obsolete

Obsolete

CMDQUE

VS

8

(MSB)
T10 VENDOR IDENTIFICATION

...

(LSB)

15
16

(MSB)
PRODUCT IDENTIFICATION

...

(LSB)

31
32

PROTECT

(MSB)
PRODUCT REVISION LEVEL

...

(LSB)

35
36
DRIVE SERIAL NUMBER

...
43
44

Vendor Unique
Seagate fills this field with 00h.

...
55
Reserved

56

QAS [a]

IUS [a]

Reserved

57
58

CLOCKING [a]

(MSB)

59

VERSION DESCRIPTOR 1

(LSB)

...
72

(MSB)

73

VERSION DESCRIPTOR 8

(LSB)

74
Reserved

...
95

Vendor specific parameters
96

(MSB)
Copyright Notice (Vendor specific)
(LSB)

n
[a]

The meanings of these fields are specific to SPI-5 (see 3.6.3). For SCSI transport
protocols other than the SCSI Parallel Interface, these fields are reserved.

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PERIPHERAL QUALIFIER and PERIPHERAL DEVICE TYPE fields
The PERIPHERAL QUALIFIER field and PERIPHERAL DEVICE TYPE field identify the peripheral device connected to the logical unit. If
the SCSI target device is not capable of supporting a peripheral device connected to this logical unit, the device server shall set these
fields to 7Fh (i.e., PERIPHERAL QUALIFIER field set to 011b and PERIPHERAL DEVICE TYPE field set to 1Fh).
The peripheral qualifier is defined in table 50 and the peripheral device type is defined in table 51
Table 50

PERIPHERAL QUALIFIER

Qualifier

Description

000b

A peripheral device having the specified peripheral device type is connected to this logical unit. If the device server
is unable to determine whether or not a peripheral device is connected, it also shall use this peripheral qualifier.
This peripheral qualifier does not mean that the peripheral device connected to the logical unit is ready for access.

001b

A peripheral device having the specified peripheral device type is not connected to this logical unit. However, the
device server is capable of supporting the specified peripheral device type on this logical unit.

010b

Reserved

011b

The device server is not capable of supporting a peripheral device on this logical unit. For this peripheral qualifier
the peripheral device type shall be set to 1Fh. All other peripheral device type values are reserved for this peripheral qualifier.

100b - 111b

Vendor specific

.

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Table 51

PERIPHERAL DEVICE TYPE

Code

Doc. [a]

Description

00h

SBC-3

Direct access block device (e.g., magnetic disk)

01h

SSC-3

Sequential-access device (e.g., magnetic tape)

02h

SSC

03h

SPC-2

04h

SBC

05h

MMC-5

Printer device
Processor device
Write-once device (e.g., some optical disks)
CD/DVD device
Scanner device (obsolete)

06h
07h

SBC

08h

SMC-3

Optical memory device (e.g., some optical disks)
Medium changer device (e.g., jukeboxes)
Communications device (obsolete)

09h

Obsolete

0Ah - 0Bh

Storage array controller device (e.g., RAID)

0Ch

SCC-2

0Dh

SES

Enclosure services device

0Eh

RBC

Simplified direct-access device (e.g., magnetic disk)

0Fh

OCRW

10h

BCC

Bridge Controller Commands

11h

OSD

Object-based Storage Device

12h

ADC-2

13h - 1Dh

Optical card reader/writer device

Automation/Drive Interface
Reserved

1Eh

Well known logical unit [b]

1Fh

Unknown or no device type

[a]

All standards are subject to revision, and parties to agreements based on the standard are encouraged to
investigate the possibility of applying the most recent editions of the listed standards.

[b]

All well known logical units use the same peripheral device type code.

RMB (Removable Media) bit
0

A removable medium (RMB) bit set to zero indicates that the medium is not removable.

1

A RMB bit set to one indicates that the medium is removable.

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VERSION field
The VERSION field indicates the implemented version of the SPC standard and is defined in table 52.
Table 52

VERSION field codes

Code

Description

00h

The device does not claim conformance to any standard.

02h

Obsolete

03h

The device complies to ANSI INCITS 301-1997 (SPC).

04h

The device complies to ANSI INCITS 351-2001 (SPC-2).

05h

The device complies to ANSI INCITS 408-2005 (SPC-3).

06h

The device complies to T10/1731-D (SPC-4)

Code

Description

Code

Description

01h

Obsolete (SCSI=001b)

07h

Reserved

08h - 0Ch

Obsolete (ECMA=001b)

0Dh - 3Fh

Reserved

40h - 44h

Obsolete (ISO=01b)

45h - 47h

Reserved

48h - 4Ch

Obsolete (ISO=01b & ECMA=001b)

4Dh - 7Fh

Reserved

80h - 84h

Obsolete (ISO=10b)

85h - 87h

Reserved

88h - 8Ch

Obsolete (ECMA=001b)

8Dh - FFh

Reserved

NORMACA (Normal ACA Supported
1

The Normal ACA Supported (NORMACA) bit set to one indicates that the device server supports a NACA bit set to one in the CDB
CONTROL byte and supports the ACA task attribute (see SAM-5).

0

A NORMACA bit set to zero indicates that the device server does not support a NACA bit set to one and does not support the ACA
task attribute.

HISUP (Hierarchical Support) bit
0

A hierarchical support (HISUP) bit set to zero indicates the SCSI target device does not use the hierarchical addressing model to
assign LUNs to logical units.

1

A HISUP bit set to one indicates the SCSI target device uses the hierarchical addressing model to assign LUNs to logical units.

RESPONSE DATA FORMAT field
A RESPONSE DATA FORMAT field value of two indicates that the data shall be in the format defined in this manual. Response data format
values less than two are obsolete. Response data format values greater than two are reserved.
ADDITIONAL LENGTH field
The ADDITIONAL LENGTH field indicates the length in bytes of the remaining standard INQUIRY data. The relationship between the
ADDITIONAL LENGTH field and the CDB ALLOCATION LENGTH field is defined in 2.2.6.
SCCS (SCC Supported) bit
1
0

An SCC Supported (SCCS) bit set to one indicates that the SCSI target device contains an embedded storage array controller component. See SCC-2 for details about storage array controller devices.
An SCCS bit set to zero indicates that the SCSI target device does not contain an embedded storage array controller component.

ACC (Access Controls Coordinator) bit
1

An Access Controls Coordinator (ACC) bit set to one indicates that the SCSI target device contains an access controls coordinator
that may be addressed through this logical unit.

0

An ACC bit set to zero indicates that no access controls coordinator may be addressed through this logical unit. If the SCSI target
device contains an access controls coordinator that may be addressed through any logical unit other than the ACCESS CONTROLS well known logical unit, then the ACC bit shall be set to one for LUN 0.

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TPGS (Target Port Group Support) field
The contents of the target port group support (TPGS) field (see table 53) indicate the support for asymmetric logical unit access.
Table 53
Code

Target Port Group Support codes
Description

00b

The SCSI target device does not support asymmetric logical unit access or supports a form of asymmetric
access that is vendor specific. Neither the REPORT TARGET GROUPS nor the SET TARGET GROUPS commands is supported.

01b

Only implicit asymmetric logical unit access (see SPC-4) is supported. The SCSI target device is capable of
changing target port asymmetric access states without a SET TARGET PORT GROUPS command. The
REPORT TARGET PORT GROUPS command is supported and the SET TARGET PORT GROUPS command
is not supported.

10b

Only explicit asymmetric logical unit access (i.e., the TPGS field contains 10b or 11b) is supported. The SCSI
target device only changes target port asymmetric access states as requested with the SET TARGET PORT
GROUPS command. Both the REPORT TARGET PORT GROUPS command and the SET TARGET PORT
GROUPS command are supported.

11b

Both explicit and implicit asymmetric logical unit access are supported. Both the REPORT TARGET PORT
GROUPS command and the SET TARGET PORT GROUPS commands are supported.

3PC (Third-Party Copy) bit
1

A Third-Party Copy (3PC) bit set to one indicates that the SCSI target device supports third-party copy commands such as the
EXTENDED COPY command.

0

A 3PC bit set to zero indicates that the SCSI target device does not support such commands.

PROTECT bit
0

A PROTECT bit set to zero indicates that the logical unit does not support protection information (i.e. type 0) (see SPC-4 and SBC3).

1

A PROTECT bit set to one indicates that the logical unit supports type 1 protection, type 2 protection, or type 3 protection (see
SBC-3). The SPT field in the Extended INQUIRY Data VPD page (see 4.4.7) indicates which type of protection the logical unit supports.

ENCSERV (Enclosure Services) bit
1

An Enclosure Services (ENCSERV) bit set to one indicates that the SCSI target device contains an embedded enclosure services
component. See SES for details about enclosure services, including a device model for an embedded enclosure services device.

0

An ENCSERV bit set to zero indicates that the SCSI target device does not contain an embedded enclosure services component.

MULTIP (Multi Port) bit
1

A Multi Port (MULTIP) bit set to one indicates that this is a multi-port (two or more ports) SCSI target device and conforms to the
SCSI multi-port device requirements found in the applicable standards (e.g., SAM-5, a SCSI transport protocol standard and possibly provisions of a command standard).

0

A MULTIP bit set to zero indicates that this SCSI target device has a single port and does not implement the multi-port requirements.

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CMDQUE (Command Queuing) bit
If the logical unit does not support the BQUE bit, CMDQUE bit shall be set to one indicating that the logical unit supports the task management model (see SAM-5).
If the logical unit supports the BQUE bit, the CMDQUE bit and BQUE bit indicate whether the logical unit supports the full task management model as described in table 54.
Table 54

BQue and CmdQue bit combinations

BQue

CmdQue

Description

0

0

Obsolete

0

1

Full task management model supported

1

0

Basic task management model supported

1

1

Illegal combination of BQUE and CMDQUE bits

T10 VENDOR IDENTIFICATION field
The T10 VENDOR IDENTIFICATION field contains eight bytes of left-aligned ASCII data (see 4.4.2) identifying the vendor of the product.
The T10 vendor identification shall be one assigned by INCITS. Bytes 8 through 15 contain the ASCII characters that represent “SEAGATE” (53h 45h 41h 47h 41h 54h 45h 20h (space)).
PRODUCT IDENTIFICATION
The PRODUCT IDENTIFICATION field contains sixteen bytes of left-aligned ASCII data (see 4.4.2) defined by Seagate. Bytes 16 through
31 indicate the drive model with 20h (space) used as a filler. The table below is an example of drive test data returned by the drive. Bytes
16 and 17 will contain 53 54 for all drive models.
Byte 18 through 26 values that may be returned by a Seagate 15K5 parallel SCSI drive:
Parallel SCSI
Fibre Channel (FC)
Serial Attached SCSI (SAS)
ST92811A
ST373455LW
ST373455LC

53
53
53
53
53
53

54
54
54
54
54
54

33
33
33
33
33
33

33
33
31
31
37
37

30
30
35
35
33
33

30
30
36
36
34
34

36
36
38
38
35
35

35
35
35
35
35
35

35
35
35
35
4C
4C

4C
4C
4C
4C
57
43

57
43
57
43
20
20

Refer to the applicable Seagate product manual to get the actual test string.
PRODUCT REVISION LEVEL field
The PRODUCT REVISION LEVEL field contains four bytes of left-aligned ASCII data defined by Seagate. Bytes 32 through 35 contain the
four ASCII digits representing the last four digits of the product Firmware Release number.
VERSION DESCRIPTOR fields
The VERSION DESCRIPTOR fields provide for identifying up to eight standards to which the SCSI target device claims conformance. The
value in each VERSION DESCRIPTOR field shall be selected from the Version Descriptor Values Table in the current SPC standard. All
version descriptor values not listed in table 55 are reserved. Technical Committee T10 of INCITS maintains an electronic copy of the information in the Version Descriptor Values Table on its world wide web site (http://www.t10.org/). In the event that the T10 world wide web site
is no longer active, access may be possible via the INCITS world wide web site (http://www.incits.org), the ANSI world wide web site (http:/
/www.ansi.org), the IEC site (http://www.iec.ch/), the ISO site (http://www.iso.ch/), or the ISO/IEC JTC 1 web site (http://www.jtc1.org/). It is
recommended that the first version descriptor be used for the SCSI architecture standard, followed by the physical transport standard if
any, followed by the SCSI transport protocol standard, followed by the appropriate SPC version, followed by the device type command set,
followed by a secondary command set if any. Refer to the latest SPC version for a complete list of descriptor values.
Copyright Notice field
Seagate uses bytes 96 - 143 to provide a copyright notice that begins “Copyright (c) XXXX Seagate All rights reserved,” where “XXXX”
indicates the year the drive’s firmware code was built (for example: 2005).

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3.6.3

SCSI Parallel Interface specific INQUIRY data

Portions of bytes 6 and 7 and all of byte 56 of the standard INQUIRY data shall be used only by SCSI target devices that implement the
SCSI Parallel Interface. These fields are noted in table 49. For details on how the SPI-specific fields relate to the SCSI Parallel Interface
see SPI-n (where n is 2 or greater). Table 55 shows just the SPI-specific standard INQUIRY fields. The definitions of the SCSI Parallel
Interface specific fields shall be as follows.
Table 55
Bit
Byte

SPI-specific standard INQUIRY bits
7

6

5

4

3

2

1

SEE table 49

6
SEE table 49

7

WBUS16

SYNC

0
ADDR16

SEE table 49

Obsolete

SEE table 49

...

...
Reserved

56

CLOCKING

QAS

IUS

ADDR16 (wide SCSI address 16) bit
1
A wide SCSI address 16 (ADDR16) bit of one indicates that the SCSI target device supports 16-bit wide SCSI addresses.
0

A value of zero indicates that the SCSI target device does not support 16-bit wide SCSI addresses.

WBUS16 (wide bus 16) bit
1

A wide bus 16 (WBUS16) bit of one indicates that the SCSI target device supports 16-bit wide data transfers.

0

A value of zero indicates that the SCSI target device does not support 16-bit wide data transfers.

SYNC (synchronous transfer) bit
1

A synchronous transfer (SYNC) bit of one indicates that the SCSI target device supports synchronous data transfer.

0

A value of zero indicates the SCSI target device does not support synchronous data transfer.

The obsolete bit 2 in byte 7 indicates whether the SCSI target device supports an obsolete data transfers management mechanism defined
in SPI-2.
Table 56 defines the relationships between the ADDR16 and WBUS16 bits.
Table 56

ADDR and WBUS bit relationships

addr16

wbus16

Description

0

0

8 bit wide data path on a single cable with 8 SCSI IDs supported

0

1

16 bit wide data path on a single cable with 8 SCSI IDs supported

1

1

16 bit wide data path on a single cable with 16 SCSI IDs supported

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CLOCKING field
The CLOCKING field shall not apply to asynchronous transfers and is defined in table 57.
Table 57

CLOCKING codes

Code

Description

00b

Indicates the target port supports only ST

01b

Indicates the target port supports only DT

10b

Reserved

11b

Indicates the target port supports ST and DT

QAS (Quick Arbitration And Selection Supported) bit
1
A quick arbitration and selection supported (QAS) bit of one indicates that the target port supports quick arbitration and selection.
0

A value of zero indicates that the target port does not support quick arbitration and selection.

IUS (information units supported) bit
1

An information units supported (IUS) bit of one indicates that the SCSI target device supports information unit transfers.

0

A value of zero indicates that the SCSI target device does not support information unit transfers.

The acronyms ST and DT and the terms 'quick arbitration and selection' and 'information units' are defined in SPI-5.
3.6.4

Vital product data

The application client requests the vital product data information by setting the EVPD bit to one and specifying the page code of a vital
product data. See 4.4 for details about vital product data. The information returned consists of configuration data (e.g., vendor
identification, product identification, model, serial number), manufacturing data (e.g., plant and date of manufacture), field replaceable unit
data and other vendor specific or device specific data. If the device server does not implement the requested page, the command shall be
terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID
FIELD IN CDB.
The device server should have the ability to process the INQUIRY command even when an error occurs that prohibits normal command
completion. In such a case, CHECK CONDITION status should be returned for commands other than INQUIRY or REQUEST SENSE.
The sense data returned may contain the field replaceable unit code. The vital product data may be obtained for the failing device using the
INQUIRY command.
This manual defines a format that allows device-independent application client software to display the vital product data returned by the
INQUIRY command. The contents of the data may be vendor specific, and may be unusable without detailed information about the device.
This manual does not define the location or method of storing the vital product data. The retrieval of the data may require completion of
initialization operations within the device, that may induce delays before the data is available to the application client. Time-critical
requirements are an implementation consideration and are not addressed in the standard.

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3.7

LOG SELECT command

The LOG SELECT command (see table 58) provides a means for an application client to manage statistical information maintained by the
SCSI target device about the SCSI target device or its logical units. Device servers that implement the LOG SELECT command shall also
implement the LOG SENSE command. Structures in the form of log parameters within log pages are defined as a way to manage the log
data. The LOG SELECT command provides for sending zero or more log pages via the Data-Out Buffer. This manual defines the format of
the log pages (see 4.2.2), but does not define the conditions and events that are logged. Application clients should issue LOG SENSE
commands prior to issuing LOG SELECT commands to determine supported log pages and page lengths.
Table 58
Bit
Byte

LOG SELECT command
7

6

5

4

3

2

1

0

PCR

SP

OPERATION CODE (4Ch)

0

Reserved

1
PC

2

PAGE CODE
SUBPAGE CODE

3
(MSB)

4

Reserved

...

(LSB)

6
(MSB)

7

PARAMETER LIST LENGTH
8

(LSB)

CONTROL

9
PCR (Parameter Code Reset) bit

The parameter code reset (PCR) bit instructs a device server whether or not to set parameters to their vendor specific default values (e.g.,
zero) as described in table 61.
SP (Save Parameters) bit
The save parameters (SP) bit instructs a device server whether or not to save parameters to non-volatile memory as described in table 61.
PC (Page Control) field
The page control (PC) field specifies which data counter parameter values (i.e., when the FORMAT AND LINKING field (see 4.2.2) contains 00b or 10b) shall be processed by a device server in response to a LOG SELECT command as described in table 59. The PC field
shall be ignored for list parameters (i.e., when the FORMAT AND LINKING field contains 01b or 11b).
Table 59

Page Control (PC) field values

Values

Description

00b

Threshold values

01b

Cumulative values

10b

Default threshold values

11b

Default cumulative values

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The threshold values and cumulative values for data counter parameters are:
1) the current values if there has been an update to a cumulative parameter value (e.g., by a LOG SELECT command or by a device
specific event) in the specified page or pages since the last logical unit reset occurred;
2) the saved values, if saved parameters are implemented, current values have been saved, and an update has not occurred since
the last logical unit reset; or
3) the vendor specific default values, if saved values are not available or not implemented.
When evaluated together, the combination of the values in the PCR bit, the SP bit, and the PC field specify the actions that a SCSI target
device performs while processing a LOG SELECT command (see table 61).
PARAMETER LIST LENGTH field
If the PARAMETER LIST LENGTH field is set to zero, the PAGE CODE field and SUBPAGE CODE field specify the log page or log pages
to which the other CDB fields apply (see 3.7.1).
Since each log page in the parameter list contains a PAGE CODE field and SUBPAGE CODE field (see 4.2.2), the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID
FIELD IN CDB, if:
a) the PARAMETER LIST LENGTH field contains a value other than zero, and:
A) the PAGE CODE field contains a value other than zero; or
B) the SUBPAGE CODE field contains a value other than zero.
The PARAMETER LIST LENGTH field specifies the length in bytes of the parameter list that shall be located in the Data-Out Buffer.
If the PARAMETER LIST LENGTH field contains zero, no log pages shall be transferred. This condition shall not be considered an error.
The LOG SELECT command shall be processed as described in 3.7.1.
3.7.1

Processing LOG SELECT when the parameter list length is zero

If the PARAMETER LIST LENGTH field is set to zero (i.e., when there is no parameter data being sent with a LOG SELECT command),
the SCSI target device responds by processing the log parameter values as described in this subclause.
PAGE CODE field and SUBPAGE CODE field
The PAGE CODE field and SUBPAGE CODE field (see table 60) specify the log page or log pages to which the other CDB fields apply
(see table 60).
Table 60

PAGE CODE field and SUBPAGE CODE field

PAGE CODE field

[a]

SUBPAGE CODE field

Description
All log parameters in all log pages

[a]

00h

00h

00h to 3Fh

01h to FEh

00h to 3Fh

FFh

All log parameters in the log pages specified by page code and all subpage codes

01h to 3Fh

00h

All log parameters in the log page specified by the page code

All log parameters in the log page specified by the page code and subpage code

This is equivalent to the LOG SELECT command operation specified by previous versions of this standard.

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Table 61 defines the meaning of the combinations of values for the PCR bit, the SP bit, and the PC field.
PCR bit, SP bit, and PC field meanings when parameter list length is zero (Sheet 1 of 2)

Table 61
PCR
bit

SP
bit

PC
field

Description

0b

0b

0xb

This is not an error. The device server shall make no changes to any log parameter values and
shall not save any values to non-volatile media.

0b

1b

00b

The device server shall make no changes to any log parameter values and shall process the
optional saving of current parameter values as follows:
a) if the values are current threshold data counter parameters, then:
A) if the device server implements saving of the current threshold values, the device server
shall save all current threshold values to non-volatile media; or
B) if the device server does not implement saving of the current threshold values, the device
server shall terminate the command. [a]
or
b) if the values are current list parameters, then:
A) if the device server implements saving of the current list parameters, the device server
shall save all current list parameters to non-volatile media; or
B) if the device server does not implement saving of the current list parameters, the device
server shall terminate the command. [a]

0b

1b

01b

The device server shall make no change to any log parameter values and shall process the
optional saving of current parameter values as follows:
a) if the values are current cumulative data counter parameters, then:
A) if the device server implements saving of the current cumulative values, the device server
shall save all current cumulative values to non-volatile media; or
B) if the device server does not implement saving of the current cumulative values, the
device server shall terminate the command. [a]
or
b) if the values are current list parameters, then:
A) if the device server implements saving of the current list parameters, the device server
shall save all current list parameters to non-volatile media; or
B) if the device server does not implement saving of the current list parameters, the device
server shall terminate the command. [a]

0b

xb

10b

The device server shall set all current threshold values to the vendor specific default threshold
values [b] and shall not save any values to non-volatile media.

0b

xb

11b

The device server shall set all current cumulative values to the vendor specific default cumulative
values [b] and shall not save any values to non-volatile media.

[a]

The command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST,
and the additional sense code set to INVALID FIELD IN CDB.

[b]

Vendor specific default threshold values and vendor specific default cumulative values may be zero.

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PCR bit, SP bit, and PC field meanings when parameter list length is zero (Sheet 2 of 2)

Table 61
PCR
bit

SP
bit

PC
field

Description

1b

0b

xxb

The device server shall:
a) set all current threshold values to the vendor specific default threshold values; [b]
b) set all current cumulative values to the vendor specific default cumulative values; [b]
c) set all list parameters to their vendor specific default values; and
d) not save any values to non-volatile media.

1b

1b

00b

The device server shall process the optional saving of current threshold values as follows:
a) if the device server implements saving of the current threshold values, the device server
shall:
1) save all current threshold values to non-volatile media;
2) set all current threshold values to the vendor specific default threshold values [b];
3) set all current cumulative values to the vendor specific default cumulative values [b],
and
4) set all list parameters to their vendor specific default values.
or
b) if the device server does not implement saving of the current threshold values, the device
server shall terminate the command. [a]

1b

1b

01b

The device server shall process the optional saving of current cumulative values as follows:
a) if the device server implements saving of the current cumulative values, the device server
shall:
1) save all current cumulative values to non-volatile media;
2) set all current threshold values to the vendor specific default threshold values [b];
3) set all current cumulative values to the vendor specific default cumulative values [b],
and
4) set all list parameters to their vendor specific default values.
or
b) if the device server does not implement saving of the current cumulative values, the device
server shall terminate the command. [a]

1b

1b

1xb

The device server shall:
a) set all current threshold values to the vendor specific default threshold values [b];
b) set all current cumulative values to the vendor specific default cumulative values [b];
c) set all list parameters to their vendor specific default values; and
d) not save any values to non-volatile media.

[a]

The command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST,
and the additional sense code set to INVALID FIELD IN CDB.

[b]

Vendor specific default threshold values and vendor specific default cumulative values may be zero.

The current cumulative values may be updated by the device server as defined for the specific log page or by the application client using
the LOG SELECT command. The current threshold values may only be modified by the application client via the LOG SELECT command.
Note.

Log pages or log parameters that are not available may become available at some later time (e.g., after the logical unit has
become ready).

Additional information about the LOG SELECT command is in Section 3.7.
The application client should send log pages in ascending order by page code value if the Data-Out Buffer contains multiple log pages. If
the Data-Out Buffer contains multiple log parameters within a log page, then they should be sent in ascending order by parameter code
value. If the application client sends log pages out of order or parameter codes out of order, the command shall be terminated with CHECK
CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN PARAMETER
LIST.

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3.8

LOG SENSE command

The LOG SENSE command (see table 62) provides a means for the application client to retrieve statistical or other operational information
maintained by the SCSI target device about the SCSI target device or its logical units. It is a complementary command to the LOG
SELECT command. See clause 4.2 of this manual for more information on returned log pages.
Table 62
Bit
Byte

LOG SENSE command
7

6

5

4

3

OPERATION CODE

0
PC

2

SUBPAGE CODE

4

Reserved
(MSB)

6
7

(MSB)

8

0

Obsolete

SP

PAGE CODE

3

5

1

(4Dh)

Reserved

1

2

PARAMETER POINTER
ALLOCATION LENGTH

(LSB)
(LSB)

CONTROL

9
SP (Saving Parameters) bit
1

If saving log parameters is implemented, an SP bit set to one specifies that the device server shall perform the specified LOG
SENSE command and shall save all log parameters identified as saveable by the DS bit to a nonvolatile, vendor specific location.
Saving parameters is an optional function of the LOG SENSE command. If the logical unit does not implement saving log parameters and if the save parameters (SP) bit is set to one, then the command shall be terminated with CHECK CONDITION status, with
the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN CDB.

0

An SP bit set to zero specifies the device server shall perform the specified LOG SENSE command and shall not save any log
parameters.

For data counter log parameters (i.e., when the FORMAT AND LINKING field in the parameter control byte in the log parameter structure
(see 4.2.2.2) contains 00b or 10b), the page control (PC) table 59 specifies which log parameter values are to be returned by a device
server in response to a LOG SENSE command.
For list parameters (i.e., when the FORMAT ANDLINKING field in the parameter control byte in the log parameter structure (see 4.2.2.2)
contains 01b or 11b), the PC field shall be ignored. If the parameters specified by the PAGE CODE field and SUBPAGE CODE field in the
CDB are list parameters, then the parameter values returned by a device server in response to a LOG SENSE command are determined
as follows:
1)
2)
3)

the current list parameter values, if there has been an update to a list parameter value (e.g., by a LOG SELECT command or by a
device specific event) in the specified page or pages since the last logical unit reset occurred;
the saved list parameter values, if saved parameters are implemented and an update has not occurred since the last logical unit
reset; or
the vendor specific default list parameter values, if saved values are not available or not implemented and an update has not
occurred since the last logical unit reset.

PAGE CODE and SUBPAGE CODE Fields
The PAGE CODE field and SUBPAGE CODE field specify which log page of data is being requested. If the log page code and subpage
combination is reserved or not implemented, the command shall be terminated with CHECK CONDITION status, with the sense key set to
ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN CDB.
PARAMETER POINTER field
The PARAMETER POINTER field allows the application client to request parameter data beginning from a specific parameter code to the
maximum allocation length or the maximum parameter code supported by the logical unit, whichever is less. If the value of the PARAMETER POINTER field is larger than the largest available parameter code known to the device server for the specified log page, the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code
set to INVALID FIELD IN CDB.
ALLOCATION LENGTH field
The ALLOCATION LENGTH field is defined in 2.2.6.
Log parameters within the specified log page shall be transferred in ascending order according to parameter code. Additional information
about the LOG SENSE command is in 4.2.
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3.9

MODE SELECT(6) command

The MODE SELECT(6) command (see table 63) provides a means for the application client to specify medium, logical unit, or peripheral
device parameters to the device server. Device servers that implement the MODE SELECT(6) command shall also implement the MODE
SENSE(6) command. Application clients should issue MODE SENSE(6) prior to each MODE SELECT(6) to determine supported mode
pages, page lengths, and other parameters.
Table 63
Bit
Byte

MODE SELECT(6) command
7

6

5

4

3

2

1

0

OPERATION CODE (15h)

0
Reserved

1
2

PF

Reserved

SP

Reserved

3
4

PARAMETER LIST LENGTH

5

CONTROL

Logical units shall share mode parameter header and block descriptor values across all I_T nexuses. I_T nexus loss shall not affect mode
parameter header, block descriptor, and mode page values.
Logical units shall maintain current and saved values of each mode page based on any of the policies listed in table 64. The mode page
policy used for each mode page may be reported in the Mode Page Policy VPD page (see 4.4.12).
Table 64

Mode page policies

Mode page policy

Number of mode page copies

Shared

One copy of the mode page that is shared by all I_T nexuses.

Per target port

A separate copy of the mode page for each target port with each copy shared by all initiator ports.

Per I_T nexus

A separate copy of the mode page for each I_T nexus

After a logical unit reset, each mode parameter header, block descriptor, and mode page shall revert to saved values if supported or default
values if saved values are not supported.
If an application client sends a MODE SELECT command that changes any parameters applying to other I_T nexuses, the device server
shall establish a unit attention (see SAM-5) condition for the initiator port associated with every I_T nexus except the I_T nexus on which
the MODE SELECT command was received, with the additional sense code set to MODE PARAMETERS CHANGED.
PF (Page Format) bit
0

A page format (PF) bit set to zero specifies that all parameters after the block descriptors are vendor specific.

1

A PF bit set to one specifies that the MODE SELECT parameters following the header and block descriptor(s) are structured as
pages of related parameters and are as defined in this manual.

SP (save pages) bit
0

A save pages (SP) bit set to zero specifies that the device server shall perform the specified MODE SELECT operation, and shall
not save any mode pages. If the logical unit implements no distinction between current and saved mode pages and the SP bit is set
to zero, the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the
additional sense code set to INVALID FIELD IN CDB. An SP bit set to one specifies that the device server shall perform the specified MODE SELECT operation, and shall save to a nonvolatile vendor specific location all the saveable mode pages including any
sent in the Data-Out Buffer. Mode pages that are saved are specified by the parameter saveable (PS) bit that is returned in the first
byte of each mode page by the MODE SENSE command.

1

If the PS bit is set to one in the MODE SENSE data, then the mode page shall be saveable by issuing a MODE SELECT command
with the SP bit set to one. If the logical unit does not implement saved mode pages and the SP bit is set to one, then the command
shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code
set to INVALID FIELD IN CDB.

PARAMETER LIST LENGTH field
The PARAMETER LIST LENGTH field specifies the length in bytes of the mode parameter list that shall be contained in the Data-Out Buffer. A parameter list length of zero specifies that the Data-Out Buffer shall be empty. This condition shall not be considered as an error.
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If the parameter list length results in the truncation of any mode parameter header, mode parameter block descriptor(s), or mode page,
then the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional
sense code set to PARAMETER LIST LENGTH ERROR.
The mode parameter list for the MODE SELECT and MODE SENSE commands is defined in 3.11. Parts of each mode parameter list are
defined in a device-type dependent manner. Definitions for the parts of each mode parameter list that are unique for each device-type may
be found in the applicable command standards.
The device server shall terminate the MODE SELECT command with CHECK CONDITION status, set the sense key to ILLEGAL
REQUEST, set the additional sense code to INVALID FIELD IN PARAMETER LIST, and shall not change any mode parameters in
response to any of the following conditions:
a) If the application client sets any field that is reported as not changeable by the device server to a value other than its current
value;
b) If the application client sets any field in the mode parameter header or block descriptor(s) to an unsupported value;
c) If an application client sends a mode page with a page length not equal to the page length returned by the MODE SENSE
command for that mode page;
d) If the application client sends an unsupported value for a mode parameter and rounding is not implemented for that mode
parameter; or
e) If the application client sets any reserved field in the mode parameter list to a non-zero value and the device server checks
reserved fields.
If the application client sends a value for a mode parameter that is outside the range supported by the device server and rounding is implemented for that mode parameter, the device server handles the condition by either:
a) Rounding the parameter to an acceptable value and terminating the command as described in 2.3; or
b) Terminating the command with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional
sense code set to INVALID FIELD IN PARAMETER LIST.
A device server may alter any mode parameter in any mode page, even those reported as non-changeable, as a result of changes to other
mode parameters.
The device server validates the non-changeable mode parameters against the current values that existed for those mode parameters prior
to the MODE SELECT command.
Note.

The current values calculated by the device server may affect the application client's operation. The application client may
issue a MODE SENSE command after each MODE SELECT command, to determine the current values.

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3.10

MODE SELECT (10) command

The MODE SELECT(10) command (see table 65) provides a means for the application client to specify medium, logical unit, or peripheral
device parameters to the device server. See the MODE SELECT(6) command (see 3.9) for a description of the fields and operation of this
command. Application clients should issue MODE SENSE(10) prior to each MODE SELECT(10) to determine supported mode pages,
page lengths, and other parameters. Device servers that implement the MODE SELECT(10) command shall also implement the MODE
SENSE(10) command.
Table 65
Bit
Byte

MODE SELECT(10) command
7

6

5

4

3

2

1

0

OPERATION CODE (55h)

0
Reserved

1

PF

Reserved

SP

2
Reserved

..
6
(MSB)

7

PARAMETER LIST LENGTH
(LSB)

8
CONTROL

9
3.11

MODE SENSE(6) command

3.11.1

MODE SENSE(6) command introduction

The MODE SENSE(6) command (see table 66) provides a means for a device server to report parameters to an application client. It is a
complementary command to the MODE SELECT(6) command. Device servers that implement the MODE SENSE(6) command shall also
implement the MODE SELECT(6) command.
Table 66
Bit
Byte

MODE SENSE(6) command
7

6

5

3

2

1

0

OPERATION CODE (1Ah)

0
Reserved

1
2

4

DBD

PC

Reserved

PAGE CODE

3

SUBPAGE CODE

4

ALLOCATION LENGTH

5

CONTROL

DBD (disable block descriptors) bit
0

A disable block descriptors (DBD) bit set to zero specifies that the device server may return zero or more block descriptors in the
returned MODE SENSE data.

1

A DBD bit set to one specifies that the device server shall not return any block descriptors in the returned MODE SENSE data.

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PC (Page Control) field
The page control (PC) field specifies the type of mode parameter values to be returned in the mode pages. The PC field is defined in table
67.
Table 67

Page control (PC) field

Code

Type of parameter

Reference

00b

Current values

3.11.1.1

01b

Changeable values

3.11.1.2

10b

Default values

3.11.1.3

11b

Saved values

3.11.1.4

The PC field only affects the mode parameters within the mode pages, however the PS bit, SPF bit, PAGE CODE field, SUBPAGE CODE
field, and PAGE LENGTH field should return current values (i.e., as if PC is set to 00b). The mode parameter header and mode parameter
block descriptor should return current values.
Some SCSI target devices may not distinguish between current and saved mode parameters and report identical values in response to a
PC field of either 00b or 11b. See also the description of the save pages (SP) bit in the MODE SELECT command.
PAGE CODE and SUBPAGE CODE fields
The PAGE CODE and SUBPAGE CODE fields specify which mode pages and subpages to return (see table 290).
ALLOCATION LENGTH field
The ALLOCATION LENGTH field is defined in 2.2.6.
An application client may request any one or all of the supported mode pages from the device server. If an application client issues a
MODE SENSE command with a page code or subpage code value not implemented by the logical unit, the command shall be terminated
with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN
CDB.
If an application client requests all supported mode pages, the device server shall return the supported pages in ascending page code
order beginning with mode page 01h. If mode page 00h is implemented, the device server shall return mode page 00h after all other mode
pages have been returned.
If the PC field and the PAGE CODE field are both set to zero, the device server should return a mode parameter header and block
descriptor, if applicable.
The mode parameter list for all device types for MODE SELECT and MODE SENSE is defined in 3.11. Parts of the mode parameter list are
specifically defined for each device type. Definitions for the parts of each mode parameter list that are unique for each device-type may be
found in the applicable command standards.
3.11.1.1

Current values

A PC field value of 00b requests that the device server return the current values of the mode parameters. The current values returned are:
a) The current values of the mode parameters established by the last successful MODE SELECT command;
b) The saved values of the mode parameters if a MODE SELECT command has not successfully completed since the mode
parameters were restored to their saved values (see 3.7); or
c) The default values of the mode parameters if a MODE SELECT command has not successfully completed since the mode
parameters were restored to their default values (see 3.7).
3.11.1.2

Changeable values

A PC field value of 01b requests that the device server return a mask denoting those mode parameters that are changeable. In the mask,
the bits in the fields of the mode parameters that are changeable all shall be set to one and the bits in the fields of the mode parameters
that are non-changeable (i.e., defined by the logical unit) all shall be set to zero.
If the logical unit does not implement changeable parameters mode pages and the device server receives a MODE SENSE command with
01b in the PC field, then the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL
REQUEST, and the additional sense code set to INVALID FIELD IN CDB.
An attempt to change a non-changeable mode parameter using the MODE SELECT command shall result in an error condition (see 3.7).
The application client should issue a MODE SENSE command with the PC field set to 01b and the PAGE CODE field set to 3Fh to
determine which mode pages are supported, which mode parameters within the mode pages are changeable, and the supported length of
each mode page prior to issuing any MODE SELECT commands.
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3.11.1.3

Default values

A PC field value of 10b requests that the device server return the default values of the mode parameters. Unsupported parameters shall be
set to zero. Default values should be accessible even if the logical unit is not ready.
3.11.1.4

Saved values

A PC field value of 11b requests that the device server return the saved values of the mode parameters. Mode parameters not supported
by the logical unit shall be set to zero. If saved values are not implemented, the command shall be terminated with CHECK CONDITION
status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to SAVING PARAMETERS NOT SUPPORTED.
The method of saving parameters is vendor specific. The parameters are preserved in such a manner that they are retained when the
device is powered down. All saveable mode pages should be considered saved when a MODE SELECT command issued with the SP bit
set to one has returned a GOOD status or after the successful completion of a FORMAT UNIT command.
3.11.1.5

Initial responses

After a logical unit reset, the device server shall respond in the following manner:
a) If default values are requested, report the default values;
(b)

If saved values are requested, report valid restored mode parameters, or restore the mode parameters and report them. If the
saved values of the mode parameters are not able to be accessed from the nonvolatile vendor specific location, the command
shall be terminated with CHECK CONDITION status, with the sense key set to NOT READY. If saved parameters are not implemented, respond as defined in 3.11.1.4; or

(c)

If current values are requested and the current values have been sent by the application client via a MODE SELECT command,
the current values shall be returned. If the current values have not been sent, the device server shall return:
a) The saved values, if saving is implemented and saved values are available; or
b) The default values.

3.12

MODE SENSE(10) command

The MODE SENSE(10) command (see table 68) provides a means for a device server to report parameters to an application client. It is a
complementary command to the MODE SELECT(10) command. Device servers that implement the MODE SENSE(10) command shall
also implement the MODE SELECT(10) command.
Table 68
Bit
Byte

MODE SENSE(10) command
7

6

5

4

3

2

1

0

OPERATION CODE (5Ah)

0
Reserved

1

LLBAA

DBD

PC

2

Reserved

PAGE CODE
SUBPAGE CODE

3
4
...

Reserved

6
7

(MSB)

ALLOCATION LENGTH
(LSB)

8
CONTROL

9
LLBAA (Long LBA Accepted) bit
1

If the Long LBA Accepted (LLBAA) bit is set to one, the device server is allowed to return parameter data with the LONGLBA bit
equal to one.

0

If LLBAA bit is set to zero, the LONGLBA bit shall be zero in the parameter data returned by the device server.

See the MODE SENSE(6) command (3.11) for a description of the other fields and operation of this command.

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3.13

PERSISTENT RESERVE IN command

3.13.1

PERSISTENT RESERVE IN command introduction

The PERSISTENT RESERVE IN command (see table 69) is used to obtain information about persistent reservations and reservation keys
(i.e., registrations) that are active within a device server. This command is used in conjunction with the PERSISTENT RESERVE OUT
command (see 3.14).
Table 69

PERSISTENT RESERVE IN command

Bit
Byte

7

6

5

4

3

2

1

0

OPERATION CODE (5Eh)

0
Reserved

1

SERVICE ACTION

2
Reserved

...
6
(MSB)

7
8

ALLOCATION LENGTH

(LSB)

CONTROL

9

The service action codes for the PERSISTENT RESERVE IN command are defined in table 70.
Table 70
Code

PERSISTENT RESERVE IN service action codes
Name

Description

00h

READ KEYS

Reads all registered reservation keys (i.e., registrations) as described in SPC-4.

3.13.2

01h

READ RESERVATION

Reads the current persistent reservations as
described in SPC-4.

3.13.3

02h

REPORT CAPABILITIES

Returns capability information

3.13.4

03h

READ FULL STATUS

Reads complete information about all registrations
and the persistent reservations, if any

3.13.5

Reserved

Reserved

04h - 1Fh

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3.13.2

READ KEYS service action

The READ KEYS service action requests that the device server return a parameter list containing a header and a list of each currently registered I_T nexus’ reservation key. If multiple I_T nexuses have registered with the same key, then that key value shall be listed multiple
times, once for each such registration.
For more information on READ KEYS see SPC-4.
The format for the parameter data provided in response to a PERSISTENT RESERVE IN command with the READ KEYS service action is
shown in table 71.
Table 71

PERSISTENT RESERVE IN parameter data for READ KEYS

Bit
Byte

7

0

(MSB)

6

5

4

3

1

0

PRGENERATION

...

(LSB)

3
4

2

(MSB)
ADDITIONAL LENGTH (N-7)

...

(LSB)

7
Reservation key list
8

(MSB)
Reservation key [first]

...

(LSB)

15

n-7

(MSB)
Reservation key [last]

...

(LSB)

n
PRGENERATION (Persistent Reservations Generation) field

The Persistent Reservations Generation (PRGENERATION) field shall contain a 32-bit counter maintained by the device server that shall
be incremented every time a PERSISTENT RESERVE OUT command requests a REGISTER service action, a REGISTER AND IGNORE
EXISTING KEY service action, a REGISTER AND MOVE service action, a CLEAR service action, a PREEMPT service action, or a PREEMPT AND ABORT service action. The counter shall not be incremented by a PERSISTENT RESERVE IN command, by a PERSISTENT
RESERVE OUT command that performs a RESERVE or RELEASE service action, or by a PERSISTENT RESERVE OUT command that
is terminated due to an error or reservation conflict. Regardless of the APTPL bit value the PRGENERATION value shall be set to zero by
a power on.
ADDITIONAL LENGTH field
The ADDITIONAL LENGTH field contains a count of the number of bytes in the Reservation key list. The relationship between the ADDITIONAL LENGTH field and the CDB ALLOCATION LENGTH field is defined in 2.2.6.
The reservation key list contains the 8-byte reservation keys for all I_T nexuses that have been registered (see SPC-4).
3.13.3
3.13.3.1

READ RESERVATION service action
READ RESERVATION service action introduction

The READ RESERVATION service action requests that the device server return a parameter list containing a header and the persistent
reservation, if any, that is present in the device server.
For more information on READ RESERVATION see SPC-4.

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3.13.3.2

PERSISTENT RESERVE IN parameter data for READ RESERVATION

When no persistent reservation is held, the format for the parameter data provided in response to a PERSISTENT RESERVE IN command
with the READ RESERVATION service action is shown in table 72.
Table 72

PERSISTENT RESERVE IN data for READ RESERVATION with no reservation held

Bit
Byte

7

0

(MSB)

6

5

4

3

2

1

PRGENERATION

...

(LSB)

3
4

0

(MSB)
ADDITIONAL LENGTH (0000_0000h)

...

(LSB)

7
PRGENERATION field

The PRGENERATION field shall be as defined for the PERSISTENT RESERVE IN command with READ KEYS service action parameter
data (see 3.13.2).
ADDITIONAL LENGTH field
The ADDITIONAL LENGTH field shall be set to zero, indicating that no persistent reservation is held.
When a persistent reservation is held, the format for the parameter data provided in response to a PERSISTENT RESERVE IN command
with the READ RESERVATION service action is shown in table 73.
Table 73

PERSISTENT RESERVE IN parameter data for READ RESERVATION with reservation

Bit
Byte

7

0

(MSB)

6

5

4

3

2

1

PRGENERATION

...

(LSB)

3
4

(MSB)
ADDITIONAL LENGTH (0000-0010h)

...

(LSB)

7
8

0

(MSB)
RESERVATION KEY

...

(LSB)

15
16
Obsolete

...
19

Reserved

20
21

SCOPE

22
23

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PRGENERATION field
The PRGENERATION field shall be as defined for the PERSISTENT RESERVE IN command with READ KEYS service action parameter
data.
ADDITIONAL LENGTH field
The ADDITIONAL LENGTH field contains a count of the number of bytes to follow and shall be set to 16. The relationship between the
ADDITIONAL LENGTH field and the CDB ALLOCATION LENGTH field is defined in 2.2.6.
RESERVATION KEY field
The RESERVATION KEY field shall contain the reservation key under which the persistent reservation is held (see SPC-4).
SCOPE field
The SCOPE field shall be set to LU_SCOPE (see 3.13.3.3).
TYPE field
The TYPE field shall contain the persistent reservation type (see 3.13.3.4) specified in the PERSISTENT RESERVE OUT command that
created the persistent reservation.
The obsolete fields in bytes 16 through 19, byte 22, and byte 23 were defined in a previous standard.
3.13.3.3

Persistent reservations scope

The SCOPE field (see table 74) shall be set to LU_SCOPE, specifying that the persistent reservation applies to the entire logical unit.
Table 74
Code
0h

Persistent reservation scope codes
Name

Description

LU_SCOPE

Persistent reservation applies to the full logical unit

1h - 2h

Obsolete

3h - Fh

Reserved

The LU_SCOPE scope shall be implemented by all device servers that implement PERSISTENT RESERVE OUT.

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3.13.3.4

Persistent reservations type

The TYPE field (see table 75) specifies the characteristics of the persistent reservation being established for all logical blocks within the
logical unit. SPC-4 defines the persistent reservation types under which each command defined in that standard is allowed to be
processed. Each other command standard (e.g., SBC-3, SSC-3, SMC-3, MMC-5, or SES-2) defines the persistent reservation types under
which each command defined in that command standard is allowed to be processed.
Table 75
Code

Persistent reservation type codes
Name

Obsolete

0h
1h

Write
Exclusive

Exclusive
Access

6h

7h

8h

9h - Fh

Access Restrictions: Some commands (e.g., media-access commands) are only
allowed for the persistent reservation holder (see SPC-4).
Persistent Reservation Holder: There is only one persistent reservation holder.
Obsolete

4h

5h

Access Restrictions: Some commands (e.g., media-access write commands) are
only allowed for the persistent reservation holder (see SPC-4).
Persistent Reservation Holder: There is only one persistent reservation holder.
Obsolete

2h
3h

Description

Write Exclusive
– Registrants
Only

Access Restrictions: Some commands (e.g., media-access write commands) are
only allowed for registered I_T nexuses.
Persistent Reservation Holder: There is only one persistent reservation holder (see
SPC-4).

Exclusive
Access – Registrants
Only

Access Restrictions: Some commands (e.g., media-access commands) are only
allowed for registered I_T nexuses.
Persistent Reservation Holder: There is only one persistent reservation holder (see
SPC-4).

Write Exclusive
– All
Registrants

Access Restrictions: Some commands (e.g., media-access write commands) are
only allowed for registered I_T nexuses.
Persistent Reservation Holder: Each registered I_T nexus is a persistent reservation holder (see SPC-4).

Exclusive
Access – All
Registrants

Access Restrictions: Some commands (e.g., media-access commands) are only
allowed for registered I_T nexuses.
Persistent Reservation Holder: Each registered I_T nexus is a persistent reservation holder (see SPC-4).

Reserved

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3.13.4

REPORT CAPABILITIES service action

The REPORT CAPABILITIES service action requests that the device server return information on persistent reservation features.
The format for the parameter data provided in response to a PERSISTENT RESERVE IN command with the REPORT CAPABILITIES
service action is shown in table 76.
Table 76

PERSISTENT RESERVE IN parameter data for REPORT CAPABILITIES

Bit
Byte

7

0

(MSB)

6

5

RLR_C

3

TMV

3

2

1

LENGTH (0008h)

1
2

4

Reserved

CRH

SIP_C

ALLOW COMMANDS

4

0

(LSB)
ATP_C
Reserved

Reserved

PTPL_C
PTPL_A

PERSISTENT RESERVATION TYPE MASK

5
6

Reserved

7
LENGTH field

The LENGTH field indicates the length in bytes of the parameter data. The relationship between the LENGTH field and the CDB ALLOCATION LENGTH field is defined in 2.2.6.
RLR_C (Replace Lost Reservation Capable) bit
1

Indicates that the device server supports the REPLACE LOST RESERVATION service action in the PERSISTENT RESERVE OUT
command.

0

Indicates that the device server does not support the REPLACE LOST RESERVATION service action in the PERSISTENT
RESERVE OUT command. If set to 0 then the device server shall not terminate any commands with CHECK CONDITION status
with the sense key set to DATA PROTECT and the additional sense code set to PERSISTENT RESERVATION INFORMATION
LOST as described in SPC-4.

CRH (Compatible Reservation Handling) field

1

A Compatible Reservation Handling (CRH) bit set to one indicates that the device server supports the exceptions to the RESERVE
and RELEASE commands described in SPC-4.

0

A CRH bit set to zero indicates that RESERVE(6) command, RESERVE(10) command, RELEASE(6) command, and
RELEASE(10) command are processed as defined in SPC-4.

SIP_C (Specify Initiator Ports Capable) bit

1

A Specify Initiator Ports Capable (SIP_C) bit set to one indicates that the device server supports the SPEC_I_PT bit in the PERSISTENT RESERVE OUT command parameter data (see 3.14.3).

0

An SIP_C bit set to zero indicates that the device server does not support the SPEC_I_PT bit in the PERSISTENT RESERVE OUT
command parameter data.

ATP_C (Target Ports Capable) bit

1

An All Target Ports Capable (ATP_C) bit set to one indicates that the device server supports the ALL_TG_PT bit in the PERSISTENT RESERVE OUT command parameter data.

0

An ATP_C bit set to zero indicates that the device server does not support the ALL_TG_PT bit in the PERSISTENT RESERVE
OUT command parameter data.

PTPL_C (Persist Through Power Loss Capable) bit

1

A Persist Through Power Loss Capable (PTPL_C) bit set to one indicates that the device server supports the persist through power
loss capability see SPC-4 for persistent reservations and the APTPL bit in the PERSISTENT RESERVE OUT command parameter
data.

0

An PTPL_C bit set to zero indicates that the device server does not support the persist through power loss capability.

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78

TMV (Type Mask Valid) bit
1

A Type Mask Valid (TMV) bit set to one indicates that the PERSISTENT RESERVATION TYPE MASK field contains a bit map indicating which persistent reservation types are supported by the device server.

0

A TMV bit set to zero indicates that the PERSISTENT RESERVATION TYPE MASK field shall be ignored.

The ALLOW COMMANDS (see table 77) indicates whether certain commands are allowed through certain types of persistent reservations.
Table 77

ALLOW COMMANDS field

Code

Description

000b

No information is provided about whether certain commands are allowed through certain types of persistent reservations.

001b

The device server allows the TEST UNIT READY command (see 3.53) through Write Exclusive and
Exclusive Access persistent reservations and does not provide information about whether the following
commands are allowed through Write Exclusive persistent reservations:
a) the MODE SENSE, READ ATTRIBUTE, READ BUFFER, RECEIVE DIAGNOSTIC RESULTS,
REPORT SUPPORTED OPERATION CODES, and REPORT SUPPORTED TASK MANAGEMENT
FUNCTION commands (see 3.36); and
b) the READ DEFECT DATA command (see 3.26).

010b

The device server allows the TEST UNIT READY command through Write Exclusive and Exclusive
Access persistent reservations and does not allow the following commands through Write Exclusive persistent reservations:
a) the MODE SENSE, READ ATTRIBUTE, READ BUFFER, RECEIVE DIAGNOSTIC RESULTS,
REPORT SUPPORTED OPERATION CODES, and REPORT SUPPORTED TASK MANAGEMENT
FUNCTION commands; and
b) the READ DEFECT DATA command.
The device server does not allow the RECEIVE COPY RESULTS command through Write Exclusive or
Exclusive Access persistent reservations.

011b

The device server allows the TEST UNIT READY command through Write Exclusive and Exclusive
Access persistent reservations and allows the following commands through Write Exclusive persistent
reservations:
a) the MODE SENSE, READ ATTRIBUTE, READ BUFFER, RECEIVE DIAGNOSTIC RESULTS,
REPORT SUPPORTED OPERATION CODES, and REPORT SUPPORTED TASK MANAGEMENT
FUNCTION commands; and
b) the READ DEFECT DATA command.
The device server does not allow the RECEIVE COPY RESULTS command through Write Exclusive or
Exclusive Access persistent reservations.

100b

The device server allows the TEST UNIT READY command and the RECEIVE COPY RESULTS command
through Write Exclusive and Exclusive Access persistent reservations and allows the following commands
through Write Exclusive persistent reservations:
a) the MODE SENSE command, READ ATTRIBUTE command, READ BUFFER command, RECEIVE
DIAGNOSTIC RESULTS command, REPORT SUPPORTED OPERATION CODES command, and
REPORT SUPPORTED TASK MANAGEMENT FUNCTION command; and
b) the READ DEFECT DATA command.

101b to 111b

Reserved

PTPL_A (Persist Through Power Loss Activated) bit
1

A Persist Through Power Loss Activated (PTPL_A) bit set to one indicates that the persist through power loss capability is activated
(see SPC-4).

0

A PTPL_A bit set to zero indicates that the persist through power loss capability is not activated.

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79

PERSISTENT RESERVATION TYPE MASK field
The PERSISTENT RESERVATION TYPE MASK field (see table 78) contains a bit map that indicates the persistent reservation types that
are supported by the device server.
Table 78
Bit
Byte
4

Persistent Reservation Type Mask format
7

6

5

WR_EX_AR EX_AC_RO WR_EX_RO

4

3

2

1

0

Reserved

EX_AC

Reserved

WR_EX

Reserved

Reserved

5

EX_AC_AR

WR_EX_AR (Write Exclusive – All Registrants) bit
1

A Write Exclusive – All Registrants (WR_EX_AR) bit set to one indicates that the device server supports the Write Exclusive – All
Registrants persistent reservation type.

0

An WR_EX_AR bit set to zero indicates that the device server does not support the Write Exclusive – All Registrants persistent reservation type.

EX_AC_RO (Exclusive Access – Registrants Only) bit
1

An Exclusive Access – Registrants Only (EX_AC_RO) bit set to one indicates that the device server supports the Exclusive Access
– Registrants Only persistent reservation type.

0

An EX_AC_RO bit set to zero indicates that the device server does not support the Exclusive Access – Registrants Only persistent
reservation type.

WR_EX_RO (Write Exclusive – Registrants Only) bit
1

A Write Exclusive – Registrants Only (WR_EX_RO) bit set to one indicates that the device server supports the Write Exclusive –
Registrants Only persistent reservation type.

0

An WR_EX_RO bit set to zero indicates that the device server does not support the Write Exclusive – Registrants Only persistent
reservation type.

EX_AC (Exclusive Access) bit
1

An Exclusive Access (EX_AC) bit set to one indicates that the device server supports the Exclusive Access persistent reservation
type.

0

An EX_AC bit set to zero indicates that the device server does not support the Exclusive Access persistent reservation type.

WR_EX (Write Exclusive) bit
1

A Write Exclusive (WR_EX) bit set to one indicates that the device server supports the Write Exclusive persistent reservation type.

0

An WR_EX bit set to zero indicates that the device server does not support the Write Exclusive persistent reservation type.

EX_AC_AR (Exclusive Access – All Registrants)
1

An Exclusive Access – All Registrants (EX_AC_AR) bit set to one indicates that the device server supports the Exclusive Access –
All Registrants persistent reservation type.

0

An EX_AC_AR bit set to zero indicates that the device server does not support the Exclusive Access – All Registrants persistent
reservation type.

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80

3.13.5

READ FULL STATUS service action

The READ FULL STATUS service action requests that the device server return a parameter list describing the registration and persistent
reservation status of each currently registered I_T nexus for the logical unit.
For more information on READ FULL STATUS see SPC-4.
The format for the parameter data provided in response to a PERSISTENT RESERVE IN command with the READ FULL STATUS service
action is shown in table 79.
Table 79
Bit
Byte
0
...
3
4
...
7

PERSISTENT RESERVE IN parameter data for READ FULL STATUS
7

6

5

4

3

2

1

0

(MSB)
PRGENERATION
(LSB)
(MSB)
ADDITIONAL LENGTH (N-7)
(LSB)
Full status descriptors

8
...
...
n

Full status descriptor [first] (see table 80)
Full status descriptor [last] (see table 80)

PRGENERATION field
The PRGENERATION field shall be as defined for the PERSISTENT RESERVE IN command with READ KEYS service action parameter
data (see 3.13.2).
ADDITIONAL LENGTH field
The ADDITIONAL LENGTH field contains a count of the number of bytes to follow in the full status descriptors. The relationship between
the ADDITIONAL LENGTH field and the CDB ALLOCATION LENGTH field is defined in 2.2.6.
The format of the full status descriptors is shown in table 80. Each full status descriptor describes one or more registered I_T nexuses. The
device server shall return persistent reservations status information for every registered I_T nexus.
Table 80
Bit
Byte
0
...
7
8
...
11
12
13
14
...
17
18
19
20
...
23
24
...
n

PERSISTENT RESERVE IN full status descriptor format
7

6

5

4

3

2

1

0

(MSB)
RESERVATION KEY
(LSB)
Reserved
Reserved

ALL_TG_PT R_HOLDER
TYPE

SCOPE
Reserved
(MSB)

RELATIVE TARGET PORT IDENTIFIER

(LSB)

(MSB)
ADDITIONAL DESCRIPTOR LENGTH (N-23)

SCSI Commands Reference Manual, Rev. H

(LSB)
TRANSPORTID

81

RESERVATION KEY field
The RESERVATION KEY field contains the reservation key.
R_HOLDER (Reservation Holder) bit
1

A Reservation Holder (R_HOLDER) bit set to one indicates that all I_T nexuses described by this full status descriptor are registered and are persistent reservation holders.

0

A R_HOLDER bit set to zero indicates that all I_T nexuses described by this full status descriptor are registered but are not persistent reservation holders.

ALL_TG_PT (All Target Ports) bit
0

An All Target Ports (ALL_TG_PT) bit set to zero indicates that this full status descriptor represents a single I_T nexus.

1

An ALL_TG_PT bit set to one indicates that:
(a)

This full status descriptor represents all the I_T nexuses that are associated with both:

a. The initiator port specified by the TRANSPORTID field; and
b. Every target port in the SCSI target device;
(b)

All the I_T nexuses are registered with the same reservation key; and

(c)

All the I_T nexuses are either reservation holders or not reservation holders as indicated by the R_HOLDER bit.

The device server is not required to return an ALL_TG_PT bit set to one. Instead, it may return separate full status descriptors for each I_T
nexus.
R_HOLDER bit
1

If the R_HOLDER bit is set to one (i.e., if the I_T nexus described by this full status descriptor is a reservation holder), the SCOPE
field and the TYPE field are as defined in the READ RESERVATION service action parameter data (see 3.13.3).

0

If the R_HOLDER bit is set to zero, the contents of the SCOPE field and the TYPE field are not defined by this manual.

ALL_TG_PT bit
0

If the ALL_TG_PT bit set to zero, the RELATIVE TARGET PORT IDENTIFIER field contains the relative port identifier (see SPC-4)
of the target port that is part of the I_T nexus described by this full status descriptor.

1

If the ALL_TG_PT bit is set to one, the contents of the RELATIVE TARGET PORT IDENTIFIER field are not defined by this manual.

ADDITIONAL DESCRIPTOR LENGTH field
The ADDITIONAL DESCRIPTOR LENGTH field contains a count of the number of bytes that follow in the descriptor (i.e., the size of the
TRANSPORTID).
TRANSPORTID field
The TRANSPORTID field contains a TRANSPORTID (see SPC-4) identifying the initiator port that is part of the I_T nexus or I_T nexuses
described by this full status descriptor.

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82

3.14

PERSISTENT RESERVE OUT command

3.14.1

PERSISTENT RESERVE OUT command introduction

The PERSISTENT RESERVE OUT command (see table 81) is used to request service actions that reserve a logical unit for the exclusive
or shared use of a particular I_T nexus. The command uses other service actions to manage and remove such persistent reservations.
I_T nexuses performing PERSISTENT RESERVE OUT service actions are identified by a registered reservation key provided by the
application client. An application client may use the PERSISTENT RESERVE IN command to obtain the reservation key, if any, for the I_T
nexus holding a persistent reservation and may use the PERSISTENT RESERVE OUT command to preempt that persistent reservation.
Table 81
Bit
Byte

PERSISTENT RESERVE OUT command
7

6

5

4

2

1

0

OPERATION CODE (5Fh)

0
Reserved

1

SERVICE ACTION

SCOPE

2

TYPE

3

Reserved

4
5

3

(MSB)
PARAMETER LIST LENGTH

...

(LSB)

8
CONTROL

9

If a PERSISTENT RESERVE OUT command is attempted, but there are insufficient device server resources to complete the operation,
the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional
sense code set to INSUFFICIENT REGISTRATION RESOURCES.
The PERSISTENT RESERVE OUT command contains fields that specify a persistent reservation service action, the intended scope of the
persistent reservation, and the restrictions caused by the persistent reservation. The TYPE and SCOPE fields are defined in 3.13.3.4 and
3.13.3.3. If a SCOPE field specifies a scope that is not implemented, the command shall be terminated with CHECK CONDITION status,
with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN CDB.
Fields contained in the PERSISTENT RESERVE OUT parameter list specify the information required to perform a particular persistent
reservation service action.
PARAMETER LIST LENGTH field
The PARAMETER LIST LENGTH field specifies the number of bytes of parameter data for the PERSISTENT RESERVE OUT command.
The parameter list shall be 24 bytes in length and the PARAMETER LIST LENGTH field shall contain 24 (18h), if the following conditions
are true:
a) The SPEC_I_PT bit (see 3.14.3) is set to zero; and
b) The service action is not REGISTER AND MOVE.
If the SPEC_I_PT bit is set to zero, the service action is not REGISTER AND MOVE, and the parameter list length is not 24, then the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code
set to PARAMETER LIST LENGTH ERROR.
If the parameter list length is larger than the device server is able to process, the command should be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to PARAMETER LIST LENGTH ERROR.
3.14.2

PERSISTENT RESERVE OUT service actions

When processing the PERSISTENT RESERVE OUT service actions, the device server shall increment the PRGENERATION value as
specified in 3.13.2.

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83

The PERSISTENT RESERVE OUT command service actions are defined in table 82.
Table 82

PERSISTENT RESERVE OUT service action codes

Description

PRGENERATION
field incremented
(see 3.13.2)

Parameter
list format

REGISTER

Register a reservation key with the device
server (see SPC-4) or unregister a reservation key (see SPC-4).

Yes

Basic
(see 3.14.3)

01h

RESERVE

Creates a persistent reservation having a
specified SCOPE and TYPE (see SPC-4).
The SCOPE and TYPE of a persistent reservation are defined in 3.13.3.3 and 3.13.3.4.

No

Basic
(see 3.14.3)

02h

RELEASE

Releases the selected persistent reservation
(see SPC-4).

No

Basic
(see 3.14.3)

03h

CLEAR

Clears all reservation keys (i.e., registrations) and all persistent reservations (see
SPC-4).

Yes

Basic
(see 3.14.3)

04h

PREEMPT

Preempts persistent reservations and/or
removes registrations (see SPC-4).

Yes

Basic
(see 3.14.3)

05h

PREEMPT AND
ABORT

Preempts persistent reservations and/or
removes registrations and aborts all tasks for
all preempted I_T nexuses (see SPC-4)

Yes

Basic
(see 3.14.3)

06h

REGISTER AND
IGNORE EXISTING KEY

Register a reservation key with the device
server (see SPC-4) or unregister a reservation key (see SPC-4).

Yes

Basic
(see 3.14.3)

07h

REGISTER AND
MOVE

Register a reservation key for another I_T
nexus with the device server and move a
persistent reservation to that I_T nexus (see
SPC-4)

Yes

Register and
move
(see 3.14.4)

08h

REPLACE LOST
RESERVATION

Replace lost persistent reservation information (see SPC-4)

Yes

Basic
(see 3.14.3)

Code

00h

09h - 1Fh

Name

Reserved

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84

3.14.3

Basic PERSISTENT RESERVE OUT parameter list

The parameter list format shown in table 83 shall be used by the PERSISTENT RESERVE OUT command with any service action except
the REGISTER AND MOVE service action. All fields shall be sent, even if the field is not required for the specified service action and scope
values.
Table 83
Bit
Byte
0
...
7
8
...
15
16
...
19
20
21
22
23
24
...
n

PERSISTENT RESERVE OUT parameter list
7

6

5

4

3

2

1

0

(MSB)
RESERVATION KEY
(LSB)
(MSB)
SERVICE ACTION RESERVATION KEY
(LSB)
Obsolete
Reserved

SPEC_I_PT ALL_TG_PT
Reserved

Reserved

APTPL

Obsolete

Additional parameter data

The obsolete fields in bytes 16 through 19, byte 22 and byte 23 were defined in a previous standard.
RESERVATION KEY field
The RESERVATION KEY field contains an 8-byte value provided by the application client to the device server to identify the I_T nexus that
is the source of the PERSISTENT RESERVE OUT command. The device server shall verify that the contents of the RESERVATION KEY
field in a PERSISTENT RESERVE OUT command parameter data matches the registered reservation key for the I_T nexus from which
the command was received, except for:
a) The REGISTER AND IGNORE EXISTING KEY service action where the RESERVATION KEY field shall be ignored; and
b) The REGISTER service action for an unregistered I_T nexus where the RESERVATION KEY field shall contain zero; and
c) The REPLACE LOST RESERVATION service action where the RESERVATION KEY field shall contain zero.
Except as noted above, when a PERSISTENT RESERVE OUT command specifies a RESERVATION KEY field other than the reservation key
registered for the I_T nexus the device server shall return a RESERVATION CONFLICT status. Except as noted above, the reservation
key of the I_T nexus shall be verified to be correct regardless of the SERVICE ACTION and SCOPE field values.
SERVICE ACTION RESERVATION KEY field
The SERVICE ACTION RESERVATION KEY field contains information needed for the following service actions: REGISTER, REGISTER
AND IGNORE EXISTING KEY, PREEMPT, PREEMPT AND ABORT, and REPLACE LOST RESERVATION. The SERVICE ACTION RESERVATION KEY field is ignored for the following service actions: RESERVE, RELEASE, and CLEAR.
For the REGISTER service action and REGISTER AND IGNORE EXISTING KEY service action, the SERVICE ACTION RESERVATION
KEY field contains:
a) The new reservation key to be registered in place of the registered reservation key specified in the RESERVATION KEY field;
or
b) Zero to unregister the registered reservation key specified in the RESERVATION KEY field.
For the PREEMPT service action and PREEMPT AND ABORT service action, the SERVICE ACTION RESERVATION KEY field contains the reservation key of:
a) The registrations to be removed; and
b) If the SERVICE ACTION RESERVATION KEY field identifies a persistent reservation holder (see SPC-4), persistent reservations that are to be preempted.
For the REPLACE LOST RESERVATION service action, the SERVICE ACTION RESERVATION KEY field contains the new reservation
key to be registered.
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85

SPEC_I_PT (Specify Initiator Ports) bit
0

If the Specify Initiator Ports (SPEC_I_PT) bit is set to zero, the device server shall apply the registration only to the I_T nexus that
sent the PERSISTENT RESERVE OUT command.

1

If the SPEC_I_PT bit is set to one for the REGISTER service action or the REGISTER AND IGNORE EXISTING KEY service
action, then the additional parameter data shall include a list of transport IDs (see table 84) and the device server shall also apply
the registration to the I_T nexus for each initiator port specified by a TRANSPORTID. If a registration fails for any initiator port (e.g.,
if the logical unit does not have enough resources available to hold the registration information), no registrations shall be made, and
the command shall be terminated with CHECK CONDITION status.

Table 84
Bit
Byte

PERSISTENT RESERVE OUT specify initiator ports additional parameter data
7

6

5

4

3

2

1

0

24
TRANSPORTID PARAMETER DATA LENGTH (N - 27)

...
27

TransportIDs List
28

TransportID [first]

...
...

TransportID [last]

n
TRANSPORTID PARAMETER DATA LENGTH field
The TRANSPORTID PARAMETER DATA LENGTH field specifies the number of bytes of TRANSPORTIDs that follow.
The command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST:
(a)

If the value in the parameter list length field in the CDB does not include all of the additional parameter list bytes specified by the
TRANSPORTID PARAMETER DATA LENGTH field; or

(b)

If the value in the TRANSPORTID PARAMETER DATA LENGTH field results in the truncation of a TRANSPORTID.

The format of a TRANSPORTID is specified in SPC-4.
ALL_TG_PT (All Target Ports) bit
The All Target Ports (ALL_TG_PT) bit is valid only for the REGISTER service action and the REGISTER AND IGNORE EXISTING KEY
service action, and shall be ignored for all other service actions. Support for the ALL_TG_PT bit is optional.
1

If the device server receives a REGISTER service action or a REGISTER AND IGNORE EXISTING KEY service action with the
ALL_TG_PT bit set to one, it shall create the specified registration on all target ports in the SCSI target device known to the device
server (i.e., as if the same registration request had been received individually through each target port).

0

If the device server receives a REGISTER service action or a REGISTER AND IGNORE EXISTING KEY service action with the
ALL_TG_PT bit set to zero, it shall apply the registration only to the target port through which the PERSISTENT RESERVE OUT
command was received.

APTPL (Activate Persist Through Power Loss) bit
1

The Activate Persist Through Power Loss (APTPL) bit is valid only for the REGISTER service action and the REGISTER AND
IGNORE EXISTING KEY service action, and shall be ignored for all other service actions. Support for an APTPL bit equal to one is
optional. If a device server that does not support an APTPL bit set to one receives that value in a REGISTER service action or a
REGISTER AND IGNORE EXISTING KEY service action, the command shall be terminated with CHECK CONDITION status, with
the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN PARAMETER LIST. If the last
valid APTPL bit value received by the device server is one, the logical unit shall retain any persistent reservation(s) that may be
present and all reservation keys (i.e., registrations) for all I_T nexuses even if power is lost and later returned (see SPC-4).

0

If the last valid APTPL bit value received by the device server is zero, the loss of power in the SCSI target device shall release the
persistent reservation for the logical unit and remove all registered reservation keys (see SPC-4).

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86

Table 85 summarizes which fields are set by the application client and interpreted by the device server for each service action and scope
value.
Table 85

PERSISTENT RESERVE OUT service actions and valid parameters (part 1 of 2)
Parameters (part 1 of 2)

Service action

TYPE

RESERVATION
KEY

SERVICE
ACTION
RESERVATION
KEY

APTPL

Allowed SCOPE

REGISTER

ignored

ignored

valid

valid

valid

REGISTER AND
IGNORE
EXISTING KEY

ignored

ignored

ignored

valid

valid

RESERVE

LU_SCOPE

valid

valid

ignored

ignored

RELEASE

LU_SCOPE

valid

valid

ignored

ignored

ignored

ignored

valid

ignored

ignored

PREEMPT

LU_SCOPE

valid

valid

valid

ignored

PREEMPT AND
ABORT

LU_SCOPE

valid

valid

valid

ignored

REGISTER AND
MOVE

LU_SCOPE

valid

valid

valid

not
applicable [a]

REPLACE LOST
RESERVATION

LU_SCOPE

valid

valid

valid

valid

CLEAR

[a] The parameter list format for the REGISTER AND MOVE service action is described in 3.14.4.
Table 86

PERSISTENT RESERVE OUT service actions and valid parameters (part 2 of 2)
Parameters (part 2 of 2)

Service action

Allowed SCOPE
ALL_TG_PT

SPEC_I_PT

REGISTER

ignored

valid

valid

REGISTER AND IGNORE
EXISTING KEY

ignored

valid

invalid

RESERVE

LU_SCOPE

ignored

invalid

RELEASE

LU_SCOPE

ignored

invalid

ignored

ignored

invalid

PREEMPT

LU_SCOPE

ignored

invalid

PREEMPT AND ABORT

LU_SCOPE

ignored

invalid

REGISTER AND MOVE

LU_SCOPE

not
applicable [a]

invalid

LU_SCOPE

invalid

invalid

CLEAR

REPLACE LOST
RESERVATION

[a] The parameter list format for the REGISTER AND MOVE service action is described in 3.14.4.

SCSI Commands Reference Manual, Rev. H

87

3.14.4

Parameter list for the PERSISTENT RESERVE OUT command with REGISTER AND MOVE service

The parameter list format shown in table 87 shall be used by the PERSISTENT RESERVE OUT command with REGISTER AND MOVE
service action.
Table 87

PERSISTENT RESERVE OUT command with REGISTER AND MOVE service

Bit
Byte

7

0

(MSB)

6

5

4

3

2

1

RESERVATION KEY

...

(LSB)

7
8

(MSB)
SERVICE ACTION RESERVATION KEY

...

(LSB)

15
Reserved

16
Reserved

17
18

(MSB)

UNREG

RELATIVE TARGET PORT IDENTIFIER

19
20

0

APTPL

(LSB)

(MSB)
TRANSPORTID PARAMETER DATA LENGTH (N - 23)

...

(LSB)

23
24
TRANSPORTID

...
n
RESERVATION KEY field

The RESERVATION KEY field contains an 8-byte value provided by the application client to the device server to identify the I_T nexus that
is the source of the PERSISTENT RESERVE OUT command. The device server shall verify that the contents of the RESERVATION KEY
field in a PERSISTENT RESERVE OUT command parameter data matches the registered reservation key for the I_T nexus from which
the command was received. If a PERSISTENT RESERVE OUT command specifies a RESERVATION KEY field other than the reservation
key registered for the I_T nexus, the device server shall return a RESERVATION CONFLICT status.
SERVICE ACTION RESERVATION KEY field
The SERVICE ACTION RESERVATION KEY field contains the reservation key to be registered to the specified I_T nexus.
APTPL (Activate Persist Through Power Loss) bit
1

The Activate Persist Through Power Loss (APTPL) bit set to one is optional. If a device server that does not support an APTPL bit
set to one receives that value, it shall return CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the
additional sense code set to INVALID FIELD IN PARAMETER LIST. If the last valid APTPL bit value received by the device server
is one, the logical unit shall retain any persistent reservation(s) that may be present and all reservation keys (i.e., registrations) for
all I_T nexuses even if power is lost and later returned (see SPC-4).

0

If the last valid APTPL bit value received by the device server is zero, the loss of power in the SCSI target device shall release the
persistent reservation for the logical unit and remove all registered reservation keys (see SPC-4).

UNREG (Unregister) bit
0

The unregister (UNREG) bit set to zero specifies that the device server shall not unregister the I_T nexus on which the PERSISTENT RESERVE OUT command REGISTER AND MOVE service action was received.

1

An UNREG bit set to one specifies that the device server shall unregister the I_T nexus on which the PERSISTENT RESERVE
OUT command REGISTER AND MOVE service action was received.

RELATIVE TARGET PORT IDENTIFIER field
The RELATIVE TARGET PORT IDENTIFIER field specifies the relative port identifier of the target port in the I_T nexus to which the persistent reservation is to be moved.
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TRANSPORTID DESCRIPTOR LENGTH field
The TRANSPORTID DESCRIPTOR LENGTH field specifies the number of bytes of the TRANSPORTID that follows, shall be a minimum
of 24 bytes, and shall be a multiple of 4.
TRANSPORTID field
The TRANSPORTID field specifies the initiator port in the I_T nexus to which the persistent reservation is to be moved. The format of the
TransportID is defined in SPC-4.
The command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST:
a) If the value in the PARAMETER LIST LENGTH field in the CDB does not include all of the parameter list bytes specified by the
TRANSPORTID PARAMETER DATA LENGTH field; or
b) If the value in the TRANSPORTID PARAMETER DATA LENGTH field results in the truncation of a TransportID.
3.15

PRE-FETCH (10) command, PRE-FETCH (16) command

These commands are not supported by Seagate disk drives. The command shall be terminated with CHECK CONDITION status, with the
sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID COMMAND OPERATION CODE.
3.16

PREVENT ALLOW MEDIUM REMOVAL command

This command is not supported by Seagate disk drives. The drive returns CHECK CONDITION status with ILLEGAL REQUEST in the
Sense Key.
3.17

READ (6) command

This command has been declared obsolete by the T10 committee. However, it is included because it may be implemented on some
products.
The READ (6) command (see table 88) requests that the device server read the specified logical block(s) and transfer them to the data-in
buffer. Each logical block read includes user data and, if the medium is formatted with protection information enabled, protection
information. Each logical block transferred includes user data but does not include protection information. The most recent data value
written, or to be written if cached, in the addressed logical blocks shall be returned.
Table 88
Bit
Byte

READ (6) command
7

6

4

3

2

1

0

OPERATION CODE (08h)

0
1

5

Reserved

2
3

(MSB)
LOGICAL BLOCK ADDRESS

4

TRANSFER LENGTH

5

CONTROL

(LSB)

The cache control bits are not provided for this command. Direct-access block devices with cache may have values for the cache control
bits that affect the READ (6) command; however, no default values are defined by this manual. If explicit control is required, the READ (10)
command should be used.
LOGICAL BLOCK ADDRESS field
The LOGICAL BLOCK ADDRESS field specifies the first logical block accessed by this command. If the logical block address exceeds the
capacity of the medium the device server shall terminate the command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to LOGICAL BLOCK ADDRESS OUT OF RANGE.

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TRANSFER LENGTH field
The TRANSFER LENGTH field specifies the number of contiguous logical blocks of data that shall be read and transferred to the data-in
buffer, starting with the logical block specified by the LOGICAL BLOCK ADDRESS field. A TRANSFER LENGTH field set to zero specifies
that 256 logical blocks shall be read. Any other value specifies the number of logical blocks that shall be read. If the logical block address
plus the transfer length exceeds the capacity of the medium, the device server shall terminate the command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to LOGICAL BLOCK ADDRESS OUT OF RANGE.
The TRANSFER LENGTH field is constrained by the MAXIMUM TRANSFER LENGTH field in the Block Limits VPD page.
a) For the READ (10) command, READ (12) command, READ (16) command, and READ (32) command, a TRANSFER
LENGTH field set to zero specifies that no logical blocks are read.
b) Although the READ (6) command is limited to addressing logical blocks up to a capacity of 2 Gigabytes, for block lengths of
512 bytes, this command has been maintained since some system initialization routines require that the READ (6) command be
used. System initialization routines should migrate from the READ (6) command to the READ (10) command, which is capable of
addressing 2 Terabytes with block lengths of 512 bytes, or the READ (16) command to address more than 2 Terabytes.
The device server shall check the protection information read from the medium before returning status for the command as described in
table 89.
Table 89

Protection information checking for READ (6)

Logical unit
formatted with
protection
information

Yes

Shall device
server transmit
protection
information?

No

Extended INQUIRY
Field in protection
Data VPD page bit
information [e]
value [d]

If check fails [b] [c],
additional sense code

LOGICAL BLOCK
GUARD

GRD_CHK = 1

LOGICAL BLOCK GUARD CHECK
FAILED

GRD_CHK = 0

No check performed

LOGICAL BLOCK
APPLICATION TAG

APP_CHK = 1 [a]
APP_CHK = 0

LOGICAL BLOCK APPLICATION TAG
CHECK FAILED
No check performed

LOGICAL BLOCK REFERENCE TAG
[f] [g]
LOGICAL BLOCK REF_CHK = 1
CHECK FAILED
REFERENCE TAG
No check performed
REF_CHK = 0
No

No protection information available to check

[a] The device server checks the logical block application tag only if it has knowledge of the contents of the LOGICAL
BLOCK APPLICATION TAG field. The method for acquiring this knowledge is not defined by this manual.
[b] If an error is reported, the sense key shall be set to ABORTED COMMAND.
[c] If multiple errors occur, the selection of which error to report is not defined by this manual.
[d] See the Extended INQUIRY Data VPD page (see 4.4.7) for the definitions of the GRD_CHK bit, APP_CHK bit,
and REF_CHK bit.
[e] If the device server detects a:
a) LOGICAL BLOCK APPLICATION TAG field set to FFFFh and type 1 protection (See SBC-3)
or type 2 protection (See SBC-3) is enabled;
or
b) LOGICAL BLOCK APPLICATION TAG field set to FFFFh, LOGICAL BLOCK REFERENCE TAG
field set to FFFF FFFFh, and type 3 protection (See SBC-3) is enabled, then the device server
shall not check any protection information in the associated logical block.
[f]

If type 1 protection is enabled, the device server checks the logical block reference tag by comparing it to the lower 4
bytes of the LBA associated with the logical block.

[g] If type 2 protection or type 3 protection is enabled, the device server checks the logical block reference tag only if it
has knowledge of the contents of the LOGICAL BLOCK REFERENCE TAG field. The method for acquiring this
knowledge is not defined by this manual.

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3.18

READ (10) command

The READ (10) command (see table 90) requests that the device server read the specified logical block(s) and transfer them to the data-in
buffer. Each logical block read includes user data and, if the medium is formatted with protection information enabled, protection
information. Each logical block transferred includes user data and may include protection information, based on the RDPROTECT field
and the medium format. The most recent data value written in the addressed logical block shall be returned.
Table 90

READ (10) command

Bit
Byte

7

6

5

3

2

1

0

RARC

FUA_NV

Obsolete

OPERATION CODE (28h)

0
RDPROTECT

1
2

4

DPO

FUA

(MSB)
LOGICAL BLOCK ADDRESS

...

(LSB)

5
Reserved

6
7

GROUP NUMBER

(MSB)

TRANSFER LENGTH

8

(LSB)

CONTROL

9
RDPROTECT field

The device server shall check the protection information read from the medium before returning status for the command based on the
RDPROTECT field as described in table 91.
Table 91

Code

000b

RDPROTECT field (Sheet 1 of 3)
Logical unit
formatted with
protection
information

Yes [d]

Shall device server
transmit protection
information?

No

No

001b
101b [b]

Yes

No [a]

Field in
Extended INQUIRY
protection
Data VPD page bit
information [h]
value [g]

If check fails [d] [f],,
additional sense code

LOGICAL BLOCK
GUARD

GRD_CHK = 1

LOGICAL BLOCK GUARD CHECK FAILED

GRD_CHK = 0

NO CHECK PERFORMED

LOGICAL BLOCK
APPLICATION
TAG

APP_CHK = 1 [c]

LOGICAL BLOCK APPLICATION TAG
CHECK FAILED

APP_CHK = 0

NO CHECK PERFORMED

LOGICAL BLOCK
REFERENCE
TAG

REF_CHK = 1 [i]

LOGICAL BLOCK REFERENCE TAG
CHECK FAILED

REF_CHK = 0

NO CHECK PERFORMED

No protection information available to check

Yes [e]

LOGICAL BLOCK
GUARD

GRD_CHK = 1

LOGICAL BLOCK GUARD CHECK FAILED

GRD_CHK = 0

NO CHECK PERFORMED

LOGICAL BLOCK
APPLICATION
TAG

APP_CHK = 1 [c]

LOGICAL BLOCK APPLICATION TAG
CHECK FAILED

APP_CHK = 0

NO CHECK PERFORMED

LOGICAL BLOCK
REFERENCE
TAG [j]

REF_CHK = 1 [i]

LOGICAL BLOCK REFERENCE TAG
CHECK FAILED

REF_CHK = 0

NO CHECK PERFORMED

No protection information available to transmit to the data-in buffer or for checking

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Table 91

Code

RDPROTECT field (Sheet 2 of 3)
Logical unit
formatted with
protection
information

Shall device server
transmit protection
information?

Field in
Extended INQUIRY
protection
Data VPD page bit
information [h]
value [g]
LOGICAL BLOCK
GUARD

010b [b]

Yes

Yes [e]

011b

Yes

No [a]

LOGICAL BLOCK
APPLICATION
TAG

APP_CHK = 1 [c]

LOGICAL BLOCK APPLICATION TAG
CHECK FAILED

APP_CHK = 0

NO CHECK PERFORMED

LOGICAL BLOCK
REFERENCE
TAG

REF_CHK = 1 [i]

LOGICAL BLOCK REFERENCE TAG
CHECK FAILED

REF_CHK = 0

NO CHECK PERFORMED

Yes

[e]

LOGICAL BLOCK
GUARD

NO CHECK PERFORMED

LOGICAL BLOCK
APPLICATION
TAG

NO CHECK PERFORMED

LOGICAL BLOCK
REFERENCE
TAG

NO CHECK PERFORMED

No protection information available to transmit to the data-in buffer or for checking
LOGICAL BLOCK
GUARD

Yes
100b [b]

No [a]

NO CHECK PERFORMED

No protection information available to transmit to the data-in buffer or for checking

No [a]

[b]

If check fails [d] [f],,
additional sense code

Yes [e]

GRD_CHK = 1

LOGICAL BLOCK GUARD CHECK FAILED

GRD_CHK = 0

NO CHECK PERFORMED

LOGICAL BLOCK
APPLICATION
TAG

NO CHECK PERFORMED

LOGICAL BLOCK
REFERENCE
TAG

NO CHECK PERFORMED

No protection information available to transmit to the data-in buffer or for checking

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Table 91

RDPROTECT field (Sheet 3 of 3)
Logical unit
formatted with
protection
information

Code

Shall device server
transmit protection
information?

Extended INQUIRY
Field in
Data VPD page bit
protection
value [g]
information [h]

101b 111b

If check fails [d] [f],,
additional sense code

Reserved

[a] A read operation to a logical unit that supports protection information and has not been formatted with protection information shall be
terminated with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to
INVALID FIELD IN CDB.
[b] If the logical unit does not support protection information the requested command should be terminated with CHECK CONDITION
status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN CDB.
[c] If the device server has knowledge of the contents of the LOGICAL BLOCK APPLICATION TAG field, then the device server shall
check each logical block application tag. If the ATO bit in the Control mode page (see 4.3.9) is set to one, then this knowledge is
acquired from:
1. the EXPECTED LOGICAL BLOCK APPLICATION TAG field and the LOGICAL BLOCK APPLICATION TAG MASK field in the
CDB, if a READ (32) command (see 5.14) is received by the device server;
2. the Application Tag mode page (see 4.3.6), if a command other than READ (32) is received by the device server, and the ATMPE
bit in the Control mode page (see 4.3.9) is set to one; or
3. a method not defined by this standard, if a command other than READ (32) is received by the device server, and the ATMPE bit
is set to zero.
[d] If an error is reported, the sense key shall be set to ABORTED COMMAND.
[e] Transmit protection information to the data-in buffer.
[f] If multiple errors occur, the selection of which error to report is not defined by this manual.
[g] See the Extended INQUIRY Data VPD page (see 4.4.7) for the definitions of the GRD_CHK bit, the APP_CHK bit,
and the REF_CHK bit.
[h] If the device server detects:
1. a LOGICAL BLOCK APPLICATION TAG field set to FFFFh and type 1 protection (See SBC-3) or type 2 protection
(See SBC-3) is enabled; or
2. a LOGICAL BLOCK APPLICATION TAG field set to FFFFh, LOGICAL BLOCK REFERENCE TAG field set to FFFF FFFFh,
and type 3 protection (See SBC-3) is enabled, then the device server shall not check any protection information in the associated
protection information interval.
[i]

If type 1 protection is enabled, the device server checks the logical block reference tag by comparing it to the lower 4 bytes of the
LBA associated with the logical block. If type 2 protection or type 3 protection is enabled, the device server checks the LOGICAL
BLOCK REFERENCE TAG if it has knowledge of the contents of the logical block reference tag field. If type 2 protection is enabled,
then this knowledge may be acquired through the expected INITIAL LOGICAL BLOCK REFERENCE TAG field in a READ (32) command (see 3.21). If type 3 protection is enabled, then the method for acquiring this knowledge is not defined by this manual.

[j] If the DPICZ bit in the Control mode page (see 4.3.9) is set to one, then protection information shall not be checked.
DPO (Disable Page Out) bit
0

A Disable Page Out (DPO) bit set to zero specifies that the retention priority shall be determined by the RETENTION PRIORITY
fields in the Caching mode page (see 4.3.8).

1

A DPO bit set to one specifies that the device server shall assign the logical blocks accessed by this command the lowest retention
priority for being fetched into or retained by the cache. A DPO bit set to one overrides any retention priority specified in the Caching
mode page. All other aspects of the algorithm implementing the cache replacement strategy are not defined by this manual.

Note.

The DPO bit is used to control replacement of logical blocks in the cache when the application client has information on the
future usage of the logical blocks. If the DPO bit is set to one, the application client is specifying that the logical blocks
accessed by the command are not likely to be accessed again in the near future and should not be put in the cache nor
retained by the cache. If the DPO bit is set to zero, the application client is specifying that the logical blocks accessed by this
command are likely to be accessed again in the near future.

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The force unit access (FUA) and force unit access non-volatile cache (FUA_NV) bits are defined in table 92.
Table 92

Force unit access for read operations

FUA

FUA_NV

Description

0

0

The device server may read the logical blocks from volatile cache, non-volatile cache, and/or
the medium.

0

1

If the NV_SUP bit is set to one in the Extended INQUIRY Data VPD page (see 4.4.7), the
device server shall read the logical blocks from non-volatile cache or the medium. If a non-volatile cache is present and a volatile cache contains a more recent version of a logical block, the
device server shall write the logical block to:
(a) non-volatile cache; and/or
(b) the medium,
before reading it.
If the NV_SUP bit is set to zero in the Extended INQUIRY Data VPD page (see 4.4.7), the
device server may read the logical blocks from volatile cache, non-volatile cache, and/or the
medium.

1

0 or 1

The device server shall read the logical blocks from the medium. If a cache contains a more
recent version of a logical block, the device server shall write the logical block to the medium
before reading it.

RARC bit
If rebuild assist mode is supported and not enabled, then the rebuild assist recovery control (RARC) bit is ignored. If rebuild assist mode is
supported and enabled, then the RARC bit specifies that read operations are processed as defined in SBC-3.
If the rebuild assist mode is not supported and the RARC bit is set to one, then the device server should terminate the command with
CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN CDB.
LOGICAL BLOCK ADDRESS field
The LOGICAL BLOCK ADDRESS field specifies the first logical block accessed by this command. If the logical block address exceeds the
capacity of the medium the device server shall terminate the command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to LOGICAL BLOCK ADDRESS OUT OF RANGE.
GROUP NUMBER field
The GROUP NUMBER field specifies the group into which attributes associated with the command should be collected. A GROUP NUMBER field set to zero specifies that any attributes associated with the command shall not be collected into any group.
TRANSFER LENGTH field
The TRANSFER LENGTH field specifies the number of contiguous logical blocks of data that shall be read and transferred to the data-in
buffer, starting with the logical block specified by the LOGICAL BLOCK ADDRESS field. A TRANSFER LENGTH field set to zero specifies
that no logical blocks shall be read. This condition shall not be considered an error. Any other value specifies the number of logical blocks
that shall be read. If the logical block address plus the transfer length exceeds the capacity of the medium, the device server shall terminate the command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to
LOGICAL BLOCK ADDRESS OUT OF RANGE. The TRANSFER LENGTH field is constrained by the MAXIMUM TRANSFER LENGTH
field in the Block Limits VPD page.

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3.19

READ (12) command

The READ (12) command (see table 93) requests that the device server read the specified logical block(s) and transfer them to the data-in
buffer. Each logical block read includes user data and, if the medium is formatted with protection information enabled, protection
information. Each logical block transferred includes user data and may include protection information, based on the RDPROTECT field
and the medium format.
Table 93

READ (12) command

Bit
Byte

7

6

5

4

3

2

1

0

RARC

FUA_NV

Obsolete

OPERATION CODE (A8h)

0
RDPROTECT

1

DPO

FUA

(MSB)

2

LOGICAL BLOCK ADDRESS

...

(LSB)

5
(MSB)

6

TRANSFER LENGTH

...

(LSB)

9
RESTRICTED
FOR MMC-6

10

Reserved

GROUP NUMBER
CONTROL

11

See the READ (10) command for the definitions of the fields in this command.
3.20

READ (16) command

The READ (16) command (see table 94) requests that the device server read the specified logical block(s) and transfer them to the data-in
buffer. Each logical block read includes user data and, if the medium is formatted with protection information enabled, protection
information. Each logical block transferred includes user data and may include protection information, based on the RDPROTECT field
and the medium format.
Table 94
Bit
Byte

READ (16) command
7

6

5

3

2

1

0

RARC

FUA_NV

Reserved

OPERATION CODE (88h)

0
RDPROTECT

1
2

4

DPO

FUA

(MSB)
LOGICAL BLOCK ADDRESS

...

(LSB)

9
10

(MSB)
TRANSFER LENGTH

...

(LSB)

13
14

Restricted for
MMC-6

Reserved

15

GROUP NUMBER
CONTROL

See the READ (10) command for the definitions of the fields in this command.

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3.21

READ (32) command

The READ (32) command (see table 95) requests that the device server read the specified logical block(s) and transfer them to the data-in
buffer. Each logical block read includes user data and, if the medium is formatted with protection information enabled, protection
information. Each logical block transferred includes user data and may include protection information, based on the RDPROTECT field
and the medium format.
1. The READ (32) command shall only be processed if type 2 protection is enabled (see SBC-3).
Table 95
Bit
Byte
0
1
2
...
5
6
7
8
9
10
11
12
...
19
20
...
23
24
25
26
27
28
...
31

READ (32) command
7

6

5

4

3

2

1

0

FUA_NV

(LSB)
Reserved

OPERATION CODE (7Fh)
CONTROL
Reserved
Reserved

GROUP NUMBER
ADDITIONAL CDB LENGTH (18h)

(MSB)

SERVICE ACTION (0009h)
RDPROTECT

DPO

FUA
Reserved

RARC

(MSB)
LOGICAL BLOCK ADDRESS
(LSB)
(MSB)
EXPECTED INITIAL LOGICAL BLOCK REFERENCE TAG
(LSB)
(MSB)

EXPECTED LOGICAL BLOCK APPLICATION TAG

(MSB)

LOGICAL BLOCK APPLICATION TAG MASK

(LSB)
(LSB)

(MSB)
TRANSFER LENGTH
(LSB)

See the READ (10) command for the definitions of the GROUP NUMBER field, the RDPROTECT field, the DPO bit, the FUA bit, the RARC
bit, the FUA_NV bit, the LOGICAL BLOCK ADDRESS field, and the TRANSFER LENGTH field.
EXPECTED INITIAL LOGICAL BLOCK REFERENCE TAG field
When checking of the LOGICAL BLOCK REFERENCE TAG field is enabled (see table 91), the EXPECTED INITIAL LOGICAL BLOCK
REFERENCE TAG field contains the value of the LOGICAL BLOCK REFERENCE TAG field expected in the protection information of the
first logical block accessed by the command instead of a value based on the LBA.
EXPECED LOGICAL BLOCK APPLICATION TAG and LOGICAL BLOCK APPLICATION TAG MASK fields
If the ATO bit in the Control mode page (see 4.3.9) is set to one in the Control mode page (see 4.3.9) and checking of the LOGICAL
BLOCK APPLICATION TAG field is enabled (see table 91), the LOGICAL BLOCK APPLICATION TAG MASK field contains a value that is
a bit mask for enabling the checking of the LOGICAL BLOCK APPLICATION TAG field in the protection information for each logical block
accessed by the command. A LOGICAL BLOCK APPLICATION TAG MASK field bit set to one enables the checking of the corresponding
bit of the EXPECTED LOGICAL BLOCK APPLICATION TAG field with the corresponding bit of the LOGICAL BLOCK APPLICATION TAG
field in the protection information.
If the ATO bit is set to one in the Control mode page (see 4.3.9) and checking of the LOGICAL BLOCK APPLICATION TAG field is disabled
(see table 91), or if the ATO bit is set to zero, the LOGICAL BLOCK APPLICATION TAG MASK field and the EXPECTED LOGICAL
BLOCK APPLICATION TAG field shall be ignored.

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3.22

READ BUFFER command

3.22.1

READ BUFFER command introduction

The READ BUFFER command (see table 96) is used in conjunction with the WRITE BUFFER command as a diagnostic function for
testing memory in the SCSI device and the integrity of the service delivery subsystem. This command shall not alter the medium.
Table 96

READ BUFFER command

Bit
Byte

7

6

5

4

3

2

1

0

OPERATION CODE (3Ch)

0
Reserved

1

MODE
BUFFER ID

2
(MSB)

3

BUFFER OFFSET

...

(LSB)

5
(MSB)

6

ALLOCATION LENGTH

...

(LSB)

8
CONTROL

9
MODE field

The function of this command and the meaning of fields within the CDB depend on the contents of the MODE field. The MODE field is defined
in table 97.
Table 97

MODE field

MODE

Description

00h

Combined header and data a

01h

Not supported a

02h

Data

03h

Descriptor

04h - 09h

Reserved

0Ah

Echo buffer

0Bh

Echo buffer descriptor

0Ch - 19h

Reserved

1Ah

Enable expander communications protocol and Echo buffer

1Bh

Reserved

1Ch

Error history

1Dh - 1Fh

Reserved

a Mode 00h and 01h are not recommended.
ALLOCATION LENGTH field
If the MODE field is not set to one, the ALLOCATION LENGTH field is defined in 2.2.6.

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3.22.2

Combined header and data mode (00h)

The four-byte READ BUFFER header (see table 98) is followed by data bytes from the buffer.
Table 98
Bit
Byte
0
1
...
3
4
...
n

READ BUFFER header
7

6

5

4

3

2

1

0

Reserved
(MSB)
BUFFER CAPACITY
(LSB)
DATA

BUFFER CAPACITY field
The BUFFER CAPACITY field specifies the total number of data bytes available in the buffer. The buffer capacity is not reduced to reflect
the actual number of bytes written using the WRITE BUFFER command with combined header and data mode. The relationship between
the BUFFER CAPACITY field and the CDB ALLOCATION LENGTH field is defined in 2.2.6. Following the READ BUFFER header, the
device server shall transfer data from the buffer.
3.22.3

Vendor specific mode (01h)

This mode is not supported by Seagate products. If used, the drive will return CHECK CONDITION and report an ILLEGAL REQUEST/
INVALID FIELD IN CDB error.
3.22.3.1

Data mode (02h)

In this mode, the Data-In Buffer is filled only with logical unit buffer data. The BUFFER ID field specifies a buffer within the logical unit from
which data shall be transferred. Seagate assigns buffer ID codes to buffers within the logical unit. Buffer ID zero shall be supported. If more
than one buffer is supported, then additional buffer ID codes shall be assigned contiguously, beginning with one. Buffer ID code
assignments for the READ BUFFER command shall be the same as for the WRITE BUFFER command. If an unsupported buffer ID code
is selected, then the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and
the additional sense code set to INVALID FIELD IN CDB.
The BUFFER OFFSET field contains the byte offset within the specified buffer from which data shall be transferred. The application client
should conform to the offset boundary requirements returned in the READ BUFFER descriptor (see 3.22.3.2). If the device server is unable
to accept the specified buffer offset, the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL
REQUEST, and the additional sense code set to INVALID FIELD IN CDB.
3.22.3.2

Descriptor mode (03h)

In this mode, a maximum of four bytes of READ BUFFER descriptor information is returned. The device server shall return the descriptor
information for the buffer specified by the BUFFER ID field (see the description of the buffer ID in 3.22.3.1). If there is no buffer associated
with the specified buffer ID, the device server shall return all zeros in the READ BUFFER descriptor. The BUFFER OFFSET field is
reserved in this mode. The allocation length should be set to four or greater. The READ BUFFER descriptor is defined as shown in table
99.
Table 99
Bit
Byte
0
1
...
3

READ BUFFER descriptor
7

6

5

4

3

2

1

0

OFFSET BOUNDARY
(MSB)
BUFFER CAPACITY
(LSB)

OFFSET BOUNDARY field
The OFFSET BOUNDARY field returns the boundary alignment within the selected buffer for subsequent WRITE BUFFER and READ
BUFFER commands. The value contained in the OFFSET BOUNDARY field shall be interpreted as a power of two.
For READ BUFFER commands, the OFFSET BOUNDARY field (see table 100) applies to the following modes:
a) data (i.e., 02h) (see 3.22.3.1); and
b) error history (i.e., 1Ch) (see 3.22.3.6)
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The value contained in the BUFFER OFFSET field of subsequent WRITE BUFFER and READ BUFFER commands should be a multiple
of 2offset boundary as shown in table 100.
Table 100

Buffer offset boundary

Offset boundary

2Offset boundary

Buffer offsets

0h

20 = 1

Byte boundaries

1h

21 = 2

Even-byte boundaries

2h

22 = 4

Four-byte boundaries

3h

23 = 8

Eight-byte boundaries

4h

24 = 16

16-byte boundaries

.

.

FFh

Not applicable

.
0 is the only supported buffer offset

BUFFER CAPACITY field
The BUFFER CAPACITY field shall return the maximum size of the selected buffer in bytes. This capacity value only apples to data mode
(i.e., MODE field set to 02h).
Note.

In a system employing multiple application clients, a buffer may be altered between the WRITE BUFFER and READ BUFFER
commands by another application client. Buffer testing applications should ensure that only a single application client is
active. Use of reservations to all logical units on the device or linked commands may be helpful in avoiding buffer alteration
between these two commands.

3.22.3.3

Echo buffer mode (0Ah)

In this mode the device server transfers data to the application client from the echo buffer that was written by the most recent WRITE
BUFFER command with the mode field set to echo buffer received on the same I_T nexus. The READ BUFFER command shall return the
same number of bytes of data as received in the prior WRITE BUFFER command with the mode field set to echo buffer, limited by the
allocation length. The BUFFER ID and BUFFER OFFSET fields are ignored in this mode.
If no WRITE BUFFER command with the mode set to echo buffer received on this I_T nexus has completed without an error, then the
READ BUFFER command shall terminate with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the
additional sense code set to COMMAND SEQUENCE ERROR. If the data in the echo buffer has been overwritten by another I_T nexus,
the READ BUFFER command shall be terminated with CHECK CONDITION status, with the sense key set to ABORTED COMMAND, and
the additional sense code set to ECHO BUFFER OVERWRITTEN.
After a WRITE BUFFER command with the mode set to echo buffer has completed without an error, the application client may send
multiple READ BUFFER commands with the mode set to echo buffer in order to read the echo buffer data multiple times.
3.22.3.4

Echo buffer descriptor mode (0Bh)

In this mode, a maximum of four bytes of READ BUFFER descriptor information is returned. The device server shall return the descriptor
information for the echo buffer. If there is no echo buffer implemented, the device server shall return all zeros in the READ BUFFER
descriptor. The BUFFER ID field and BUFFER OFFSET field are reserved in this mode. The allocation length should be set to four or greater.
The READ BUFFER descriptor is defined as shown in table 101.
Table 101
Bit
Byte

Echo buffer descriptor
7

6

5

4

0

Reserved

1

Reserved

2

Reserved

3

3

2

1

0
EBOS

(MSB)
BUFFER CAPACITY

(LSB)

BUFFER CAPACITY field
The BUFFER CAPACITY field shall return the size of the echo buffer in bytes aligned to a four-byte boundary. The maximum echo buffer
size is 4 096 bytes.
If the echo buffer is implemented, the echo buffer descriptor shall be implemented.
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EBOS bit
1

An echo buffer overwritten supported (EBOS) bit set to one indicates either:
a) The device server returns the ECHO BUFFER OVERWRITTEN additional sense code if the data being read from the echo
buffer is not the data previously written by the same I_T nexus, or
b) The device server ensures echo buffer data returned to each I_T nexus is the same as that previously written by that I_T
nexus.

0

An EBOS bit set to zero specifies that the echo buffer may be overwritten by any intervening command received on any I_T nexus.

A READ BUFFER command with the mode set to echo buffer descriptor may be used to determine the echo buffer capacity and supported
features before a WRITE BUFFER command with the mode set to echo buffer is sent.
3.22.3.5

Enable expander communications protocol and Echo buffer (1Ah)

Receipt of a READ BUFFER command with this mode (1Ah) causes a communicative expander (see SPI-5) to enter the expanded communications protocol mode. Device servers in SCSI target devices that receive a READ BUFFER command with this mode shall process it
as if it were a READ BUFFER command with mode 0Ah (see 3.22.3.3).
3.22.3.6

Error history mode (1Ch)

3.22.3.6.1

Error history overview

This mode is used to manage and retrieve error history (see SPC-4).
If the device server is unable to process a READ BUFFER command with the MODE field set to 1Ch because of a vendor specific condition,
then the device server shall terminate the READ BUFFER command with CHECK CONDITION status, with the sense key set to ILLEGAL
REQUEST, and the additional sense code set to COMMAND SEQUENCE ERROR.
The BUFFER ID field (see table 102) specifies the action that the device server shall perform, and the parameter data, if any, that the
device server shall return.
Table 102

Error history BUFFER ID field

Code

Description

Buffer offset

Error history
I_T nexus
constrained

Reference

00h

Return error history directory

0000h

Yes

3.22.3.6.2

01h

Return error history directory and create new
error history snapshot (see 1.1 and SPC-4)

0000h

Yes

3.22.3.6.2

02h

Return error history directory and establish new
error history I_T nexus (see 1.1 and SPC-4)

0000h

No

3.22.3.6.2

03h

Return error history directory, establish new
error history I_T nexus, and create new error
history snapshot

0000h

No

3.22.3.6.2

04h to 0Fh

Reserved

10h to EFh

Return error history

F0h to FDh

Reserved

Yes
0000h to FFFFh

Yes

3.22.3.6.3

Yes

FEh

Clear error history I_T nexus

Ignored

Yes

3.22.3.6.4

FFh

Clear error history I_T nexus and release error
history snapshot

Ignored

Yes

3.22.3.6.5

The command shall be terminated with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional
sense code set to OPERATION IN PROGRESS if the device server receives a READ BUFFER command:
a) with the MODE field set to 1Ch;
b) with the BUFFER ID field set to a value that table 102 shows as constrained by error history I_T nexus;
c) if an error history I_T nexus exists and the command is received from an I_T nexus that is different that I_T nexus; and
d) an error history snapshot exists.
BUFFER OFFSET field
The BUFFER OFFSET field specifies the byte offset from the start of the buffer specified by the BUFFER ID field from which the device
server shall return data. The application client should conform to the offset boundary requirements indicated in the READ BUFFER
descriptor (see 3.22.3.2). If the buffer offset is not one of those shown in table 102 or the device server is unable to accept the specified
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buffer offset, then the device server shall terminate the READ BUFFER command with CHECK CONDITION status, with the sense key set
to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN CDB.
3.22.3.6.2

Error history directory

Whenever allowed by established error history I_T nexus constraints (see 3.22.3.6.1), if any, all error history device server actions return
an error history directory (see table 104). Some error history device server actions also discard the existing error history snapshot (see
SPC-4) and create a new error history snapshot (see table 103).
Table 103

Summary of error history directory device server actions
Error history snapshot (see SPC-4)

BUFFER ID field

Establish new error history I_T
nexus (see SPC-4)

Preserved (if exists)

Created

00h

No [a]

Yes

No [b]

01h

No [a]

No

Yes

02h

Yes

Yes

No [b]

03h

Yes

No

Yes

[a]

If no error history I_T nexus is established, a new one is established.

[b]

If no error history snapshot exists, a new one is created.

The error history directory is defined in table 104.
Table 104

Error history directory

Bit
Byte

7

0

(MSB)

6

5

4

3

2

1

.

T10 VENDOR INDENTIFICATION

...

0

(LSB)

7
VERSION

8
Reserved

9

EHS_RETRIEVED

10
Reserved

...

EHS_SOURCE

CLR_SUP
.

29
30

(MSB)

DIRECTORY LENGTH (n-31)

31

(LSB)

Error history directory list
32
Error history directory entry [first]
(see table 107)

...

.

39
...
n-7
Error history directory entry [last]
(see table 107)

...
n
T10 VENDOR INDENTIFICATION field

The T10 VENDOR INDENTIFICATION field contains eight bytes of left-aligned ASCII data identifying the manufacturer of the logical unit.
The T10 vendor identification shall be one assigned by INCITS.
Note.

The T10 VENDOR INDENTIFICATION field may contain a different value than the VENDOR INDENTIFICATION field in the
standard INQUIRY data (see 3.6.2) (e.g., this field may indicate a disk drive component vendor while the standard INQUIRY
data indicates the original equipment manufacturer).

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VERSION field
The VERSION field indicates the version and format of the vendor specific error history. The VERSION field is assigned by the vendor indicated in the T10 VENDOR INDENTIFICATION field.
EHS_RETRIEVED (error history retrieved) field
The error history retrieved (EHS_RETRIEVED) field (see table 105) indicates whether a clear error history device server action has been
requested for the error history snapshot. EHS_RETRIEVED field shall be set to 00b or 10b when the error history snapshot is created.
Table 105
Code

EHS_RETRIEVED field
Description

00b

No information

01b

The error history I_T nexus has requested buffer ID FEh (i.e., clear error history I_T nexus) or buffer ID FFh
(i.e., clear error history I_T nexus and release snapshot) for the current error history snapshot.

10b

An error history I_T nexus has not requested buffer ID FEh (i.e., clear error history I_T nexus) or buffer ID
FFh (i.e., clear error history I_T nexus and release snapshot) for the current error history snapshot.

11b

Reserved

EHS_SOURCE (error history source) field
The error history source (EHS_SOURCE) field (see table 106) indicates the source of the error history snapshot.
Table 106
Code

EHS_SOURCE field
Description

00b

The error history snapshot was created by the device server and was not created due to processing a READ
BUFFER command.

01b

Error history snapshot was created due to processing of the current READ BUFFER command

10b

Error history snapshot was created due to processing of a previous READ BUFFER command

11b

Reserved

CLR_SUPC (clear support) bit
1

A clear support (CLR_SUP) bit set to one indicates that the CLR bit is supported in the WRITE BUFFER command download error
history mode (see 3.68).

0

A CLR_SUP bit set to zero indicates that the CLR bit is not supported.

DIRECTORY LENGTH field
The DIRECTORY LENGTH field indicates the number of error history directory list bytes available to be transferred. This value shall not be
altered even if the allocation length is not sufficient to transfer the entire error history directory list.
The error history directory list contains an error history directory entry (see table 107) for each supported buffer ID in the range of 00h to
EFh. The first entry shall be for buffer ID 00h and the entries shall be in order of ascending buffer IDs. The supported buffer IDs are not
required to be contiguous. There shall not be any entries for buffer IDs greater than or equal to F0h.
Table 107
Bit
Byte

Error history directory entry
7

6

5

0

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3

2

1

0

SUPPORTED BUFFER ID

102

Table 107
Bit
Byte

Error history directory entry
7

6

5

4

3

2

1

0

1
Reserved

...
3
4

(MSB)
MAXIMUM AVAILABLE LENGTH

...

(LSB)

7
SUPPORTED BUFFER ID field
The SUPPORTED BUFFER ID field indicates the error history buffer ID associated with this entry.
MAXIMUM AVAILABLE LENGTH

The MAXIMUM AVAILABLE LENGTH field indicates the maximum number of data bytes contained in the buffer indicated by the SUPPORTED BUFFER ID field. The actual number of bytes available for transfer may be smaller.
3.22.3.6.3

Error history data buffer

Unless an error is encountered, the device server shall return parameter data that contains error history in a vendor specific format from
the error history snapshot from the specified buffer at the specified buffer offset.
If the device server receives a READ BUFFER command with the MODE field set to 1Ch from the established error history I_T nexus and
the BUFFER ID field is set to a value that the error history directory (see 3.22.3.6.2) shows as not supported, then the command shall be
terminated with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID
FIELD IN CDB.
If the value in the BUFFER OFFSET field is not supported, the command shall be terminated with CHECK CONDITION status with the
sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN CDB.
The amount of error history in the specified buffer shall be less than or equal to the number of bytes indicated by the MAXIMUM
AVAILABLE LENGTH field in the error history directory (see 3.22.3.6.2).
3.22.3.6.4

Clear error history I_T nexus

If the BUFFER ID field is set to FEh, the device server shall:
a) clear the error history I_T nexus, if any; and
b) not transfer any data.
3.22.3.6.5

Clear error history I_T nexus and release snapshot

If the BUFFER ID field is set to FFh, the device server shall:
a) clear the error history I_T nexus, if any,
b) release the error history snapshot, if any; and
c) not transfer any data.

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3.23

READ CAPACITY (10) command

3.23.1

READ CAPACITY (10) overview

The READ CAPACITY (10) command (see table 108) requests that the device server transfer 8 bytes of parameter data describing the
capacity and medium format of the direct-access block device to the data-in buffer. This command may be processed as if it has a HEAD
OF QUEUE task attribute. If the logical unit supports protection information, the application client should use the READ CAPACITY (16)
command instead of the READ CAPACITY (10) command.
Table 108
Bit
Byte

READ CAPACITY (10) command
7

6

5

4

3

2

1

0

OPERATION CODE (25h)

0

Reserved

1

Obsolete

(MSB)

2
...

LOGICAL BLOCK ADDRESS (Obsolete)
(LSB)

5
6

Reserved

7

Reserved

8

PMI
(Obsolete)

CONTROL

9

For the definition of the LOGICAL BLOCK ADDRESS field see 2.2.3.
LOGICAL BLOCK ADDRESS field
This field has been declared obsolete by the T10 committee. However, it is included because it may be implemented on some products.
The LOGICAL BLOCK ADDRESS field shall be set to zero if the PMI bit is set to zero. If the PMI bit is set to zero and the LOGICAL
BLOCK ADDRESS field is not set to zero, the device server shall terminate the command with CHECK CONDITION status with the sense
key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN CDB.
PMI (Partial Medium Indicator) bit
This bit has been declared obsolete by the T10 committee. However, it is included because it may be implemented on some products.
0

A partial medium indicator (PMI) bit set to zero specifies that the device server return information on the last logical block on the
direct-access block device.

1

A PMI bit set to one specifies that the device server return information on the last logical block after that specified in the LOGICAL
BLOCK ADDRESS field before a substantial vendor-specific delay in data transfer may be encountered.

This function is intended to assist storage management software in determining whether there is sufficient space starting with the logical
block address specified in the CDB to contain a frequently accessed data structure (e.g., a file directory or file index) without incurring an
extra delay.

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3.23.2

READ CAPACITY (10) parameter data

The READ CAPACITY (10) parameter data is defined in table 109. Any time the READ CAPACITY (10) parameter data changes, the
device server should establish a unit attention condition as described in SBC-3.
Table 109

READ CAPACITY (10) parameter data

Bit
Byte

7

0

(MSB)

6

5

4

3

2

1

0

RETURNED LOGICAL BLOCK ADDRESS

...

(LSB)

3
(MSB)

4

BLOCK LENGTH IN BYTES

...

(LSB)

7
RETURNED LOGICAL BLOCK ADDRESS field

If the number of logical blocks exceeds the maximum value that is able to be specified in the RETURNED LOGICAL BLOCK ADDRESS
field, the device server shall set the RETURNED LOGICAL BLOCK ADDRESS field to FFFFFFFFh. The application client should then
issue a READ CAPACITY (16) command (see 3.25) to retrieve the READ CAPACITY (16) parameter data.
0

If the PMI bit is set to zero, the device server shall set the RETURNED LOGICAL BLOCK ADDRESS field to the lower of:
a) the LBA of the last logical block on the direct-access block device; or
b) FFFFFFFFh.

1

If the PMI bit is set to one, the device server shall set the RETURNED LOGICAL BLOCK ADDRESS field to the lower of:
a) the last LBA after that specified in the LOGICAL BLOCK ADDRESS field of the CDB before a substantial vendor-specific delay
in data transfer may be encountered; or
b) the LBA of the last logical block on the direct-access block device.

The RETURNED LOGICAL BLOCK ADDRESS shall be greater than or equal to that specified by the LOGICAL BLOCK ADDRESS field in
the CDB.
BLOCK LENGTH IN BYTES field
The BLOCK LENGTH IN BYTES field contains the number of bytes of user data in the logical block indicated by the RETURNED LOGICAL BLOCK ADDRESS field. This value does not include protection information or additional information (e.g., ECC bytes) recorded on
the medium.

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3.24

READ CAPACITY (16) command

3.24.1

READ CAPACITY (16) command overview

The READ CAPACITY (16) command (see table 110) requests that the device server transfer parameter data describing the capacity and
medium format of the direct-access block device to the data-in buffer. This command is mandatory if the logical unit supports protection
information and optional otherwise (see SBC-3). This command is implemented as a service action of the SERVICE ACTION IN operation
code. This command may be processed as if it has a HEAD OF QUEUE task attribute.
Table 110
Bit
Byte

READ CAPACITY (16) command
7

6

5

3

2

Reserved

1

0

SERVICE ACTION (10h)

(MSB)
LOGICAL BLOCK ADDRESS (Obsolete)

...

(LSB)

9
10

1

OPERATION CODE (9Eh)

0

2

4

(MSB)

...

ALLOCATION LENGTH
(LSB)

13
14
15

Reserved

PMI
(Obsolete)

CONTROL

LOGICAL BLOCK ADDRESS field and PMI bit
See 2.2.3 for the definition of the LOGICAL BLOCK ADDRESS field.
See the READ CAPACITY (10) command (see 3.23) for the definition of the PMI bit.
ALLOCATION LENGTH field
The ALLOCATION LENGTH field (see 2.2.6) specifies the maximum number of bytes that the application client has allocated for returned
parameter data. An allocation length of zero indicates that no data shall be transferred. This condition shall not be considered as an error.
The device server shall terminate transfers to the data-in buffer when the number of bytes specified by the ALLOCATION LENGTH field
have been transferred or when all available data has been transferred, whichever is less. The contents of the parameter data shall not be
altered to reflect the truncation, if any, that results from an insufficient allocation length.

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3.24.2

READ CAPACITY (16) parameter data

The READ CAPACITY (16) parameter data is defined in table 111. Any time the READ CAPACITY (16) parameter data changes, the
device server should establish a unit attention condition as described in SPC-4.
Table 111

READ CAPACITY (16) parameter data

Bit
Byte
0
...
7
8
...
11
12

7

6

5

4

3

2

1

0

(MSB)
RETURNED LOGICAL BLOCK ADDRESS
(LSB)
(MSB)
LOGICAL BLOCK LENGTH IN BYTES
(LSB)
P_TYPE
PROT_EN
LOGICAL BLOCKS PER PHYSICAL BLOCK
EXPONENT

Reserved
P_I_EXPONENT

13
LBPME

14
15
16
...
31

LBPRZ

(MSB)

LOWEST ALIGNED LOGICAL BLOCK ADDRESS

(LSB)

Reserved

RETURNED LOGICAL BLOCK ADDRESS
The RETURNED LOGICAL BLOCK ADDRESS field and LOGICAL BLOCK LENGTH IN BYTES field of the READ CAPACITY (16) parameter data are the same as the in the READ CAPACITY (10) parameter data (see 3.23.1). The maximum value that shall be returned in the
RETURNED LOGICAL BLOCK ADDRESS field is FFFFFFFF_FFFFFFFEh.
LOGICAL BLOCK LENGTH IN BYTES field
The LOGICAL BLOCK LENGTH IN BYTES field contains the number of bytes of user data in the logical block indicated by the
RETURNED LOGICAL BLOCK ADDRESS field. This value does not include protection information or additional information (e.g., ECC
bytes) recorded on the medium.
P_TYPE (Protection Type) field and PROT_EN bit
The protection type (P_TYPE) field and the PROT_EN bit (see table 112) indicate the logical unit’s current type of protection.
Table 112

P_TYPE FIELD and PROT_EN bit

PROT_EN

P_TYPE

DESCRIPTION

0

XXXb

The logical unit is formatted to type 0 protection (see SBC-3)

1

000b

The logical unit is formatted to type 1 protection (see SBC-3)

1

001b

The logical unit is formatted to type 2 protection (see SBC-3)

1

010b

The logical unit is formatted to type 3 protection (see SBC-3)

1

011b - 111b

Reserved

P_I_EXPONENT field
The P_I_EXPONENT field may be used to determine the number of protection information intervals placed within each logical block (see
3.5.2).
The number of protection information intervals is calculated as follows:
number of protection information intervals = 2(p_i exponent)
where:
p_i exponent

is the contents of the P_I EXPONENT field

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LOGICAL BLOCKS PER PHYSICAL BLOCKS EXPONENT field
The LOGICAL BLOCKS PER PHYSICAL BLOCKS EXPONENT field is defined in table 113.
Table 113

LOGICAL BLOCKS PER PHYSICAL BLOCKS EXPONENT field

Code
0
n>0

Description
One or more physical blocks per logical block []
2n logical blocks per physical block

The number of physical blocks per logical block is not reported.
Logical Block Provisioning Management Enabled (LBPME) bit
1

If the thin provisioning enabled (TPE) bit is set to one, then the logical unit implements logical block provisioning management (see
SBC-3).

0

If the TPE bit is set to zero, then the logical unit does not implement logical block provisioning management (see SBC-3).

Logical Block Provisioning Read Zeros (LBPRZ) bit
1

If the logical block provisioning read zeros (LBPRZ) bit is set to one, then, for an unmapped LBA specified by a read operation, the
device server shall send user data with all bits set to zero to the data-in buffer.

0

If the TPRZ bit is set to zero, then, for an unmapped LBA specified by a read operation, the device server may send user data with
all bits set to any value to the data-in buffer.

LOWEST ALIGNED LOGICAL BLOCK ADDRESS field
The LOWEST ALIGNED LOGICAL BLOCK ADDRESS field indicates the LBA of the first logical block that is located at the beginning of a
physical block (SBC-3).
Note.

The highest LBA that the lowest aligned logical block address field supports is 3FFFh (i.e., 16 383).

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3.25

READ DEFECT DATA (10) command

3.25.1

READ DEFECT DATA (10) command overview

The READ DEFECT DATA (10) command (see table 114) requests that the device server transfer the medium defect data to the data-in
buffer.
Table 114
Bit
Byte

READ DEFECT DATA (10) command
7

6

5

4

3

0

OPERATION CODE (37h)

1

Reserved
Reserved

2

REQ_PLIST

REQ_GLIST

2

1

0

DEFECT LIST FORMAT

3
Reserved

...
6
7

(MSB)

8

ALLOCATION LENGTH

(LSB)

CONTROL

9

If the device server is unable to access the medium defect data, it shall terminate the command with CHECK CONDITION status. The
sense key shall be set to either MEDIUM ERROR, if a medium error occurred, or NO SENSE, if medium defect data does not exist. The
additional sense code shall be set to DEFECT LIST NOT FOUND.
Note.

Some device servers may not be able to return medium defect data until after a FORMAT UNIT command (see 3.5) has been
completed successfully.

REQ_PLIST (request primary defect list) bit
0

A request primary defect list (REQ_PLIST) bit set to zero specifies that the device server shall not return the PLIST.

1

A REQ_PLIST bit set to one specifies that the device server shall return the PLIST, if any.

REQ_GLIST (request grown defect list) bit
0

A request grown defect list (REQ_GLIST) bit set to zero specifies that the device server shall not return the GLIST.

1

A REQ_GLIST bit set to one specifies that the device server shall return the GLIST, if any.

A REQ_PLIST bit set to zero and a REQ_GLIST bit set to zero specifies that the device server shall return only the defect list header (i.e.,
the first four bytes of the defect list).
A REQ_PLIST bit set to one and a REQ_GLIST bit set to one specifies that the device server shall return both the PLIST and GLIST, if any.
The order the lists are returned in is vendor-specific. Whether the lists are merged or not is vendor-specific.
DEFECT LIST FORMAT field
The DEFECT LIST FORMAT field specifies the preferred format for the defect list. This field is intended for those device servers capable of
returning more than one format, as defined in the FORMAT UNIT command (see 3.5.5). A device server unable to return the requested format shall return the defect list in its default format and indicate that format in the DEFECT LIST FORMAT field in the defect list header (see
table 115).
If the requested defect list format and the returned defect list format are not the same, the device server shall transfer the defect data and
then terminate the command with CHECK CONDITION status with the sense key set to RECOVERED ERROR and the additional sense
code set to DEFECT LIST NOT FOUND.
ALLOCATION LENGTH field
The ALLOCATION LENGTH field is defined in 2.2.6. The application client is responsible for comparing the allocation length requested in
the CDB with the defect list length returned in the parameter data to determine whether a partial list was received. If the number of address
descriptors the device server has to report exceeds the maximum value that is able to be specified in the ALLOCATION LENGTH field, the
device server shall transfer no data and return CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN CDB.

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3.25.2

READ DEFECT DATA (10) parameter data

The READ DEFECT DATA (10) parameter data (see table 115) contains a four-byte header, followed by zero or more address descriptors.
Table 115
Bit
Byte

READ DEFECT DATA (10) parameter data
7

6

5

4

2

1

0

Reserved

0
Reserved

1
2

3

(MSB)

3

PLISTV

GLISTV

DEFECT LIST FORMAT

DEFECT LIST LENGTH (N - 3)

(LSB)

Defect List (if any)
4
ADDRESS DESCRIPTOR(S) (IF ANY)

...
n
PLISTV (PLIST valid) bit
0

A PLIST valid (PLISTV) bit set to zero indicates that the data returned does not contain the PLIST.

1

A PLISTV bit set to one indicates that the data returned contains the PLIST.

GLISTV (GLIST valid) bit
0

A GLIST valid (GLISTV) bit set to zero indicates that the data returned does not contain the GLIST.

1

A GLISTV bit set to one indicates that the data returned contains the GLIST.

DEFECT LIST FORMAT field
The DEFECT LIST FORMAT field indicates the format of the address descriptors returned by the device server. This field is defined in the
FORMAT UNIT command (see 3.5.5).
If the device server returns short block format address descriptors or long block format address descriptors, the address descriptors
contain vendor-specific values.
Note.

The use of the short block format and the long block format is not recommended for this command. There is no standard
model that defines the meaning of the block address of a defect. In the usual case, a defect that has been reassigned no longer has an LBA.

If the device server returns physical sector format address descriptors (see 3.5.5.7), it may or may not include defects in parts of the
medium not accessible to the application client. If the device server returns bytes from index format address descriptors (see 3.5.5.6), it
shall return a complete list of the defects. A complete list of the defects may include defects in areas not within the capacity returned in the
READ CAPACITY command.
DEFECT LIST LENGTH field
The DEFECT LIST LENGTH field indicates the length in bytes of the address descriptors that follow. The DEFECT LIST LENGTH is equal
to four or eight times the number of the address descriptors, depending on the format of the returned address descriptors.
The address descriptors may or may not be sent in ascending order.

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3.26

READ DEFECT DATA (12) command

3.26.1

READ DEFECT DATA (12) command overview

The READ DEFECT DATA (12) command (see Table 116) requests that the device server transfer the medium defect data to the data-in
buffer.
Table 116
Bit
Byte
0
1
2
...
5
6
...
9
10
11

READ DEFECT DATA (12) command
7

6

5

Reserved

4

3

OPERATION CODE (B7h)
REQ_PLIST REQ_GLIST

2

1

0

DEFECT LIST FORMAT

ADDRESS DESCRIPTOR INDEX
(MSB)
ALLOCATION LENGTH
(LSB)
Reserved
CONTROL

See the READ DEFECT DATA (10) command (see 3.25) for the definitions of the fields in this command that are not described in this
clause.
ADDRESS DESCRIPTOR INDEX field
The ADDRESS DESCRIPTOR INDEX field specifies the index of the first address descriptor (see Section 3.5.5.1) in the defect list that the
device server shall return. If the ADDRESS DESCRIPTOR INDEX field is set to:
a. a value less than the number of available address descriptors, then the device server shall transfer a defect list beginning with the
address descriptor that is at the ADDRESS DESCRIPTOR INDEX field value multiplied by the size of the address descriptor; or
b. a value greater than or equal to the number of available address descriptors, then the device server shall return a zero length
defect list.
ALLOCATION LENGTH field
The ALLOCATION LENGTH field is defined in SPC-4. The application client is responsible for comparing the allocation length requested in
the CDB with the DEFECT LIST LENGTH field value returned in the parameter data to determine whether a partial list was received. If the
length of all the address descriptors that are available is greater than FFFF_FFFFh, then the device server shall transfer the length of
address descriptors specified by the allocation length or the DEFECT LIST LENGTH field value plus eight, whichever is less, and complete
the command with GOOD status.

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3.26.2

READ DEFECT DATA (12) parameter data

The READ DEFECT DATA (12) parameter data (see table 117) contains an eight byte header, followed by zero or more address
descriptors.
Table 117
Bit
Byte
0
1
2
3
4
...
7

READ DEFECT DATA (12) parameter data
7

6

Reserved

5

4

3

Reserved
PLISTV
GLISTV
Reserved
Reserved

2

1

0

DEFECT LIST FORMAT

(MSB)
DEFECT LIST LENGTH (N - 7)
(LSB)
Defect List (if any)

8
...
n

Address descriptor(s) (if any)

See the READ DEFECT DATA (10) command (see 3.25.2) for the definitions of the fields in the defect list header that are not described in
this clause.
DEFECT LIST LENGTH field
The DEFECT LIST LENGTH field indicates the length in bytes of address descriptors from the beginning address descriptor specified by
the ADDRESS DESCRIPTOR INDEX field to the last address descriptor available to be returned. A value of FFFF_FFFFh in the DEFECT
LIST LENGTH field indicates that more than FFFF_FFFEh bytes are available.

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3.27

READ LONG (10) command

The READ LONG (10) command (see table 118) requests that the device server transfer data from a single logical block to the data-in
buffer. The data transferred during the READ LONG (10) command is vendor-specific, but shall include the following items recorded on the
medium:
a)

b)

if a logical block is being transferred, then:
A) user data or transformed user data for the logical block;
B) protection information or transformed protection information, if any, for the logical block; and
C) any additional information (e.g., ECC bytes) for all the physical blocks in the logical block.
or
if a physical block is being transferred, then:
A) user data or transformed user data for all the logical blocks in the physical block;
B) protection information or transformed protection information, if any, for all the logical blocks in the physical block; and
C) any additional information (e.g., ECC bytes).

If a cache contains a more recent version of a logical block, the device server shall write the logical block to the medium before reading it.
The values in the Read-Write Error Recovery mode page (see 4.3.16) do not apply to this command. The device server may perform
retries while processing this command.
Table 118
Bit
Byte
0
1
2
...
5
6
7
8
9

READ LONG (10) command
7

6

5

4

3

2

1

0

PBLOCK

CORRCT

Obsolete

OPERATION CODE (3Eh)
Reserved
(MSB)
LOGICAL BLOCK ADDRESS
(LSB)
Reserved
(MSB)

BYTE TRANSFER LENGTH

(LSB)

CONTROL

LOGICAL BLOCK ADDRESS field
See 2.2.3 for the definition of the LOGICAL BLOCK ADDRESS field.
PBLOCK bit
If there is more than one logical block per physical block (i.e., the LOGICAL BLOCKS PER PHYSICAL BLOCK EXPONENT field in the
READ CAPACITY (16) data is set to a non-zero value), then the device server shall support the physical block (PBLOCK) bit.
1

a PBLOCK bit set to one specifies that the device server shall return the entire physical block containing the specified logical block,
and

0

a PBLOCK bit set to zero specifies that the device server shall return bytes representing only the specified logical block.

If there are one or more physical blocks per logical block (i.e., the LOGICAL BLOCKS PER PHYSICAL BLOCK EXPONENT field in the
READ CAPACITY (16) data is set to zero) and the PBLOCK bit is set to one, then the device server shall return CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN CDB.
CORRCT (correct) bit
0

A correct (CORRCT) bit set to zero specifies that a logical block be read without any correction made by the device server. A CORRCT bit set to zero should result in GOOD status unless data is not transferred for some reason other than that the data is non-correctable. In this case the appropriate status and sense data shall be returned.

1

A CORRCT bit set to one specifies that the data be corrected by ECC before being transferred to the data-in buffer.

BYTE TRANSFER LENGTH field
The BYTE TRANSFER LENGTH field specifies the number of bytes of data that shall be read from the specified logical block and transferred to the data-in buffer. If the BYTE TRANSFER LENGTH field is not set to zero and does not match the available data length, the
device server shall terminate the command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN CDB. In the sense data (see SPC-4), the VALID and ILI bits shall each be set to one and the
INFORMATION field shall be set to the difference (i.e., residue) of the requested byte transfer length minus the actual available data length
in bytes. Negative values shall be indicated by two's complement notation.
A BYTE TRANSFER LENGTH field set to zero specifies that no bytes shall be read. This condition shall not be considered an error.

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3.28

READ LONG (16) command

The READ LONG (16) command (see table 119) requests that the device server transfer data from a single logical block to the data-in
buffer. The data transferred during the READ LONG (16) command is vendor-specific, but shall include the following items recorded on the
medium:
a)

b)

if a logical block is being transferred, then:
A) user data or transformed user data for the logical block;
B) protection information or transformed protection information, if any, for the logical block; and
C) any additional information (e.g., ECC bytes) for all the physical blocks in the logical block.
or
if a physical block is being transferred, then:
A) user data or transformed user data for all the logical blocks in the physical block;
B) protection information or transformed protection information, if any, for all the logical blocks in the physical block; and
C) any additional information (e.g., ECC bytes).

If a cache contains a more recent version of a logical block, the device server shall write the logical block to the medium before reading it.
The values in the Read-Write Error Recovery mode page (see 4.3.16) do not apply to this command. The device server may perform
retries while processing this command. This command is implemented as a service action of the SERVICE ACTION IN operation code.
Table 119
Bit
Byte

READ LONG (16) command
7

6

4

3

2

1

Reserved

1

SERVICE ACTION (11h)

(MSB)
LOGICAL BLOCK ADDRESS

...

(LSB)

9
10

Reserved

11
12

0

OPERATION CODE (9Eh)

0

2

5

(MSB)

13
14
15

BYTE TRANSFER LENGTH
Reserved

(LSB)
PBLOCK

CORRCT

CONTROL

See the READ LONG (10) command (see 3.27) for the definitions of the fields in this command.

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3.29

REASSIGN BLOCKS command

3.29.1

REASSIGN BLOCKS command overview

The REASSIGN BLOCKS command (see table 120) requests that the device server reassign defective logical blocks to another area on
the medium set aside for this purpose. The device server should also record the location of the defective logical blocks in the GLIST, if
supported. This command shall not alter the contents of the PLIST.
The parameter list provided in the data-out buffer contains a defective LBA list that contains the LBAs of the logical blocks to be
reassigned. The device server shall reassign the parts of the medium used for each logical block in the defective LBA list. More than one
physical block may be relocated by each LBA. If the device server is able to recover user data and protection information, if any, from the
original logical block, it shall write the recovered user data and any protection information to the reassigned logical block. If the LBA is
unmapped, then the device server shall cause the LBA to become mapped and write the data that was retrieved during a read operation
specifying the LBA that was reassigned to the logical block (see SBC-3). If the device server is unable to recover user data and protection
information, if any, it shall write vendor-specific data as the user data and shall write a default value of FFFFFFFF_FFFFFFFFh as the
protection information, if enabled. The data in all other logical blocks on the medium shall be preserved.
The effect of specifying a logical block to be reassigned that previously has been reassigned is to reassign the logical block
again. Although not likely, over the life of the medium, a logical block may be assigned to multiple physical block addresses
until no more spare locations remain on the medium.

Note.

Table 120
Bit
Byte

REASSIGN BLOCKS command
7

6

5

4

3

2

1

0

LONGLBA

LONGLIST

OPERATION CODE (07h)

0

Reserved

1
2

Reserved

...
4

CONTROL

5
LONGLBA (Long LBA) bit
0

A long LBA (LONGLBA) bit set to zero specifies that the REASSIGN BLOCKS defective LBA list contains four byte LBAs.

1

A LONGLBA bit set to one specifies that the REASSIGN BLOCKS defective LBA list contains eight byte LBAs.

3.29.2

REASSIGN BLOCKS parameter list

The REASSIGN BLOCKS parameter list (see table 121) contains a four-byte parameter list header followed by a defective LBA list
containing one or more LBAs.
Table 121
Bit
Byte

REASSIGN BLOCKS parameter list
7

6

5

4

3

2

1

0

0
...

Parameter list header (see table 122 or table 123)

3
4
...

DEFECTIVE LBA LIST (if any)

n

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LONGLIST bit
If LONGLIST is set to zero, the parameter list header is defined in table 122.

0

Table 122
Bit
Byte

REASSIGN BLOCKS short parameter list header
7

6

5

4

0

3

2

1

0

Reserved

1
(MSB)

2

DEFECT LIST LENGTH

3

(LSB)

If LONGLIST is set to one, the parameter list header is defined in table 123.

1

Table 123

REASSIGN BLOCKS long parameter list header

Bit
Byte

7

0

(MSB)

6

5

...

4

3

2

1

0

DEFECT LIST LENGTH

3

(LSB)

DEFECT LIST LENGTH field
The DEFECT LIST LENGTH field indicates the total length in bytes of the DEFECTIVE LBA LIST field. The DEFECT LIST LENGTH field
does not include the parameter list header length and is equal to either:
a) four times the number of LBAs, if the LONGLBA bit is set to zero; or
b) eight times the number of LBAs, if the LONGLBA bit is set to one.
DEFECTIVE LBA LIST field
The DEFECTIVE LBA LIST field contains a list of defective LBAs. Each LBA is a four-byte field if the LONGLBA bit is set to zero or an
eight-byte field if the LONGLBA bit is set to one. The LBAs shall be in ascending order.
If the direct-access block device has insufficient capacity to reassign all of the specified logical blocks, the device server shall terminate the
command with CHECK CONDITION status with the sense key set to HARDWARE ERROR and the additional sense code set to NO
DEFECT SPARE LOCATION AVAILABLE.
If the direct-access block device is unable to successfully complete a REASSIGN BLOCKS command, the device server shall terminate
the command with CHECK CONDITION status with the appropriate sense data (see SPC-4). The first LBA not reassigned shall be
returned in the COMMAND-SPECIFIC INFORMATION field of the sense data. If information about the first LBA not reassigned is not
available, or if all the defects have been reassigned, the COMMAND-SPECIFIC INFORMATION field shall be set to FFFFFFFFh if fixed
format sense data is being used or FFFFFFFF_FFFFFFFFh if descriptor format sense data is being used.
If the REASSIGN BLOCKS command failed due to an unexpected unrecoverable read error that would cause the loss of data in a logical
block not specified in the defective LBA list, the LBA of the unrecoverable block shall be returned in the INFORMATION field of the sense
data and the VALID bit shall be set to one.
If the REASSIGN BLOCKS command returns CHECK CONDITION status and the sense data COMMAND-SPECIFIC INFORMATION field
contains a valid LBA, the application client should remove all LBAs from the defective LBA list prior to the one returned in the COMMANDSPECIFIC INFORMATION field. If the sense key is MEDIUM ERROR and the INFORMATION field contains the valid LBA, the application
client should insert that new defective LBA into the defective LBA list and reissue the REASSIGN BLOCKS command with the new defective LBA list. Otherwise, the application client should perform any corrective action indicated by the sense data and then reissue the REASSIGN BLOCKS command with the new defective LBA list.

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3.30

RECEIVE DIAGNOSTIC RESULTS command

The RECEIVE DIAGNOSTIC RESULTS command (see table 124) requests analysis data be sent to the application client Data-In Buffer
after completion of a SEND DIAGNOSTIC command (see 3.47), or, optionally, SCSI-3 Enclosure Services (SES) pages be sent to the
initiator. Support for SES is indicated in the drive product manual.
If no data in the optional Page format was requested by the SEND DIAGNOSTICs command (0 in bit 4 of Table 173), the data returned to
the initiator is in the format shown in Table 125.
All FRU and error code definitions are unique to the product and intended for factory/field maintenance personnel.
Table 124
Bit
Byte

RECEIVE DIAGNOSTIC RESULTS command
7

6

5

3

2

1

0

OPERATION CODE (1Ch)

0

Reserved

1

PCV

PAGE CODE

2
3

4

(MSB)

4

ALLOCATION LENGTH

(LSB)

CONTROL

5
PCV (Page Code Valid) bit
0

A page code valid (PCV) bit set to zero specifies that the device server return parameter data based on the most recent SEND
DIAGNOSTIC command (e.g., the diagnostic page with the same page code as that specified in the most recent SEND DIAGNOSTIC command). The response to a RECEIVE DIAGNOSTIC RESULTS command with the PCV bit set to zero is vendor-specific if:
a) The most recent SEND DIAGNOSTIC command was not a SEND DIAGNOSTIC command defining parameter data to return;
b) A RECEIVE DIAGNOSTIC RESULTS command with a PCV bit set to one has been processed since the last SEND DIAGNOSTIC command was processed; or
c) No SEND DIAGNOSTIC command defining parameter data to return has been processed since power on, hard reset, or logical unit reset.

1

A page code valid (PCV) bit set to one specifies that the device server return the diagnostic page specified in the PAGE CODE field.
Page code values are defined in Table 226.

PAGE CODE field
The PAGE CODE field identifies which diagnostic page is requested as a result of a RECEIVE DIAGNOSTIC RESULTS command with the
PCV bit equal to one, or returned as a result of a RECEIVE DIAGNOSTIC RESULTS parameter data.
ALLOCATION LENGTH field
The ALLOCATION LENGTH field (see 2.2.6) shall specify the number of bytes the initiator has allocated for returned data. An ALLOCATION LENGTH of zero indicates that no data shall be transferred. Any other value indicates the maximum number of bytes that shall be
transferred. The drive terminates the DATA IN phase when ALLOCATION LENGTH bytes have been transferred or when all available data
has been transferred to the initiator, whichever is less.

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Table 125

[1]
[2]

[3]

[4]

Diagnostic Data Bytes

Code

Byte

Description

00h

0

ADDITIONAL LENGTH (MSB) [1]

28h

1

ADDITIONAL LENGTH (LSB) [1]

XXh

2

FRU CODE (most probable) [2]

XXh

3

FRU CODE [2]

XXh

4

FRU CODE [2]

XXh

5

FRU CODE (least probable) [2]

XXh

6

ERROR CODE (MSB) [3]

V.U.

7

ERROR CODE (LSB) [4]

V.U.

8 thru n

Additional vendor unique fault information (if any) (not available)

ADDITIONAL LENGTH. This two byte value indicates the number of additional bytes included in the diagnostic data list. For example,
if no product unique byte (byte 7) is available, this value would be 0006h. A value of 0000h means that there are no additional bytes.
A FIELD REPLACEABLE UNIT (FRU) Code is a byte that identifies an assembly that may have failed. The codes will be listed in
probability order, with the most probable assembly listed first and the least probable listed last. A code of 00h indicates there is no
FRU information and a code of 01h indicates the entire unit should be replaced. Seagate drives return 00h in these bytes.
The ERROR CODE is a two byte value that provides information designating which part of a diagnostic operation has failed. The LSB
of the error code is vendor unique and defined in note [4]. Usually, Seagate drives support only some subset of the list given in note
[4].
Vendor Unique codes supported by Seagate devices.

Diagnostic Fault Codes
01h

Formatter Diagnostic Error

02h

Microprocessor RAM Diagnostic Error

04h

No Drive Ready

08h

No Sector or Index Detected

09h

Fatal Hardware Error While Doing Drive Diagnostics

0Ch

No Drive Command Complete

10h

Unable to Set Drive Sector Size

14h

Unable to Clear Drive Attention

18h

Unable to Start Spindle Motor

20h

Unable to Recal Drive

30h

Unable to Send Write Current Data to Drive

34h

Unable to Issue Drive SEEK Command

40h

Unable to Read User Table From Drive

41h

Ran Out of Sectors While Doing Drive Diagnostics

42h

Unable to Read Reallocation Table

43h

Unable to Read ETF Log

45h

Firmware Read from disk or Sent by Host has an Invalid Checksum

60h

Thermal Calibration Failure

70h

Microprocessor Internal Timer Error

80h

Buffer Controller Diagnostic Error

81h

Buffer RAM Diagnostic Error

C1h

Data Miscompare While Doing Drive Diagnostics

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3.31

RELEASE(6) command

This command has been declared obsolete by the T10 committee. However, it is included because it may be implemented on some
products.
The RELEASE(6) command (see table 126) is used to release a previously reserved logical unit. This subclause describes only those
instances where the RELEASE(6) command differs from the RELEASE(10) command. Except for the instances described in this
subclause, the RELEASE(6) command shall function exactly like the RELEASE(10) command (see 3.35).
Table 126
Bit
Byte

RELEASE(6) Command
7

6

5

4

3

2

1

0

OPERATION CODE (17h)

0
Reserved

1

Obsolete

2

Obsolete

3

Reserved

4

Reserved

5

CONTROL

The RELEASE(6) command shall not release third-party reservations.
Obsolete Bits 1 through 4 of Byte 1 provided a method, limited to device addresses 0 through 7, to handle third-party reservations in earlier
versions of the SCSI standard. The obsolete method has been replaced by the RESERVE(10) and RELEASE(10).
Byte 1 Bit 0 and Byte 2 provide an obsolete way to release previously reserved extents within a logical unit. If Byte 1, Bit 0 is equal to one,
device servers not implementing the obsolete capability shall terminate the command with CHECK CONDITION status and the sense key
shall be set to ILLEGAL REQUEST.
3.32

RELEASE (10) command

This command has been declared obsolete by the T10 committee. However, it is included because it may be implemented on some
products.
3.32.1

RELEASE(10) command introduction

The RELEASE(10) command (see table 127) is used to release a previously reserved logical unit.
Table 127
Bit
Byte

RELEASE (10) Command
7

6

5

4

3

2

0

LONGID

Obsolete

OPERATION CODE (57h)

0
Reserved

1

3RDPTY

Reserved

2

Obsolete

3

THIRD-PARTY DEVICE ID

4

Reserved

5

Reserved

6

Reserved

7

1

(MSB)

8
9

PARAMETER LIST LENGTH

(LSB)

CONTROL

The RESERVE and RELEASE commands provide a basic mechanism for contention resolution in multiple-initiator systems. See 5.5.1 for
a general description of reservations and the commands that manage them. A reservation may only be released by a RELEASE command
from the initiator that made it. It is not an error for an application client to attempt to release a reservation that is not currently valid, or is
held by another initiator. In this case, the device server shall return GOOD status without altering any other reservation.

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Byte 1 Bit 0 and Byte 2 provide an obsolete way to release previously reserved extents within a logical unit. If Byte 1, Bit 0 is equal to one,
device servers not implementing the obsolete capability shall terminate the command with CHECK CONDITION status and the sense key
shall be set to ILLEGAL REQUEST.
3.32.2

Logical unit release

Logical unit reservation release is mandatory if the RELEASE(10) command is implemented. This command shall cause the device server
to terminate all non-third-party logical unit reservations that are active from the initiator to the specified logical unit.
3.32.3

Third-party release

Third-party reservation release is optional if the RELEASE(10) command is implemented. Third-party release allows an application client
to release a logical unit that was previously reserved using third-party reservation (see 7.21.3).
3RDPTY (third-party) bit
0

If the third-party (3RDPTY) bit is zero, then a third-party release is not requested. If the 3RDPTY bit is zero then the LONGID bit
and the PARAMETER LIST LENGTH field shall be ignored.

1

If the 3RDPTY bit is one then the device server shall release the specified logical unit, but only if the initiator ID, 3RDPTY bit, and
THIRD-PARTY DEVICE ID are identical when compared to the RESERVE command that established the reservation. The device
server shall not modify the mode parameters for commands received from the third-party device even if the device server implements the transfer of mode parameters with a third-party RESERVE command.

Note.

If a target implements independent storage of mode parameters for each initiator, a third-party RESERVE command copies
the current mode parameters for the initiator that sent the RESERVE command to the current mode parameters for the initiator specified as the third-party device (e.g., a copy manager SCSI device). A unit attention condition notifies the third-party of
the changed mode parameters due to the reservation. A successful third-party RELEASE command does not change the
third-party devices' current mode parameters back to their previous values. The third-party device may issue MODE SENSE
and MODE SELECT commands to query and modify the mode parameters.

THIRD-PARTY DEVICE ID field and LONGID bit
If the THIRD-PARTY DEVICE ID value associated with the reservation release is smaller than 255, the LONGID bit may be zero and the ID
value sent in the CDB THIRD-PARTY DEVICE ID field. Device ID formats are protocol specific. If the LONGID bit is zero, the PARAMETER LIST LENGTH field shall be set to zero. If the THIRD-PARTY DEVICE ID is greater than 255, the LONGID bit shall be one.
Device servers that support device IDs greater than 255 shall accept commands with LONGID equal to one. Device servers whose
devices IDs are limited to 255 or smaller may reject commands with LONGID equal to one with CHECK CONDITION status and a sense
key of ILLEGAL REQUEST.
If the LONGID bit is one, the parameter list length shall be eight, and the parameter list shall have the format shown in table 96. If the
LONGID bit is one, the THIRD-PARTY DEVICE ID field in the CDB shall be ignored. If the LONGID bit is one and the parameter list length
is not eight, the device server shall return a CHECK CONDITION status with a sense key of ILLEGAL REQUEST.
Table 128
Bit
Byte

RELEASE(10) parameter list
7

6

5

4

3

2

1

0

0
...

THIRD-PARTY DEVICE ID

7

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3.33

REPORT IDENTIFYING INFORMATION

The REPORT IDENTIFYING INFORMATION command requests that the device server send device identification information to the
application client.
The device server shall return the same identifying information regardless of the I_T nexus being used to retrieve the identifying
information.
Processing a REPORT IDENTIFYING INFORMATION command may require the enabling of a nonvolatile memory within the logical unit.
If the nonvolatile memory is not ready, the command shall be terminated with CHECK CONDITION status, rather than wait for the
nonvolatile memory to become ready. The sense key shall be set to NOT READY and the additional sense code shall be set as described
in table (see table Note.). This information should allow the application client to determine the action required to cause the device server to
become ready.
Table 129
Bit
Byte

REPORT IDENTIFYING INFORMATION command
7

6

5

4

2

1

0

OPERATION CODE (A3h)

0
Reserved

1

SERVICE ACTION (05h)

2

Reserved

3
4

RESTRICTED (see SCC-2)

5
6

3

(MSB)
ALLOCATION LENGTH

...

(LSB)

9
INFORMATION TYPE

10

Reserved

CONTROL

11
ALLOCATION LENGTH field
The ALLOCATION LENGTH field is defined in 2.2.6.
INFORMATION TYPE field

The INFORMATION TYPE field (see table 130) specifies the type of information to be reported.
Table 130

INFORMATION TYPE

Code

Description

Length

Reference

0000000b

Peripheral device identifying information

0 to 64 bytes

Table 30

0000010b

Peripheral device text identifying information.

65 to
512bytes

Table 30

1111111b

Identifying information supported. The parameter data contains a list of
supported identifying information types and the maximum length of each.

0 to 256
bytes

3.33.1

xxxxxx1b

Restricted.

All other

Reserved.

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The REPORT IDENTIFYING INFORMATION parameter data format used when the INFORMATION TYPE field is set to 0000000b or
0000010b is shown in table 131.
Table 131

REPORT IDENTIFYING INFORMATION parameter data

Bit
Byte

7

6

5

4

0

3

2

1

0

Reserved

1
(MSB)

2

INFORMATION LENGTH (n - 3)

(LSB)

3
4
INFORMATION

...
n
INFORMATION LENGTH

The INFORMATION LENGTH field indicates the length in bytes of the INFORMATION field. The relationship between the INFORMATION
LENGTH field and the CDB ALLOCATION LENGTH field is defined in 2.2.6.
INFORMATION
The INFORMATION field contains the identifying information that has the specified information type (see table 130).
3.33.1

IDENTIFYING INFORMATION SUPPORTED parameter data

The REPORT IDENTIFYING INFORMATION parameter data format used when the INFORMATION TYPE field is set to 1111111b is shown
in table 132.
Table 132
Bit
Byte

REPORT IDENTIFYING INFORMATION SUPPORTED parameter data
7

6

5

4

3

2

1

0

Reserved

0
1
2

(MSB)

IDENTIFYING INFORMATION LENGTH (n - 3)

3

(LSB)

Identifying information descriptor list
4
...

Identifying information descriptor [first] (see table 133)

7
...
n-3
...

Identifying information descriptor [last]

n
IDENTIFYING INFORMATION LENGTH field
The IDENTIFYING INFORMATION LENGTH field indicates the length in bytes of the identifying information descriptor list. The relationship
between the IDENTIFYING INFORMATION LENGTH field and the CDB ALLOCATION LENGTH field is defined in 2.2.6.

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Identifying information descriptor list
The Identifying information descriptor list contains an identifying information descriptor (see table (see table 133)) for each identifying information type supported by the device server. The identifying information descriptors shall be sorted in increasing order by information type.
Table 133

Identifying Information descriptor

Bit
Byte

7

6

5

4

3

2

1

INFORMATION TYPE

0

0
Reserved

Reserved

1
(MSB)

2

MAXIMUM INFORMATION LENGTH

(LSB)

3
INFORMATION TYPE field
The INFORMATION TYPE field indicates the information type (see table 130).
MAXIMUM LENGTH field

The MAXIMUM LENGTH field indicates the maximum number of bytes supported for identifying information that has the indicated information type.
3.34

REPORT LUNS command

The REPORT LUNS command (see table 134) requests that the peripheral device logical unit inventory accessible to the I_T nexus be
sent to the application client. The logical unit inventory is a list that shall include the logical unit numbers of all logical units having a
PERIPHERAL QUALIFIER value of 000b (see table 50). Logical unit numbers for logical units with PERIPHERAL QUALIFIER values other
than 000b and 011b may be included in the logical unit inventory. Logical unit numbers for logical units with a PERIPHERAL QUALIFIER
value of 011b shall not be included in the logical unit inventory.
Table 134
Bit
Byte

REPORT LUNS command
7

6

5

4

3

0

OPERATION CODE (A0h)

1

Reserved

2

SELECT REPORT

2

1

0

3
Reserved

...
5
6

(MSB)

...

ALLOCATION LENGTH
(LSB)

9
10

Reserved

11

CONTROL

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SELECT REPORT field
The SELECT REPORT field (see table 135) specifies the types of logical unit addresses that shall be reported.
Table 135

SELECT REPORT field

Code

Description
The list shall contain the logical units accessible to the I_T nexus with the following addressing methods (see SAM-5):
Logical unit addressing method,
Peripheral device addressing method; and
Flat space addressing method.

00h

If there are no logical units, the LUN LIST LENGTH field shall be zero.
01h

The list shall contain only well known logical units, if any. If there are no well known logical units, the
LUN LIST LENGTH field shall be zero.

02h

The list shall contain all logical units accessible to the I_T nexus.
Reserved

03h - FFh

ALLOCATION LENGTH field
The ALLOCATION LENGTH field is defined in 2.2.6. The allocation length should be at least 16.
The REPORT LUNS command shall return CHECK CONDITION status only when the device server is unable to return the requested
report of the logical unit inventory.
If a REPORT LUNS command is received from an I_T nexus with a pending unit attention condition (i.e., before the device server reports
CHECK CONDITION status), the device server shall perform the REPORT LUNS command (see SAM-5).
The REPORT LUNS parameter data should be returned even though the device server is not ready for other commands. The report of the
logical unit inventory should be available without incurring any media access delays. If the device server is not ready with the logical unit
inventory or if the inventory list is null for the requesting I_T nexus and the SELECT REPORT field set to 02h, then the device server shall
provide a default logical unit inventory that contains at least LUN 0 or the REPORT LUNS well known logical unit. A non-empty peripheral
device logical unit inventory that does not contain either LUN 0 or the REPORT LUNS well known logical unit is valid.
If a REPORT LUNS command is received for a logical unit that the SCSI target device does not support and the device server is not
capable of returning the logical unit inventory, then the command shall be terminated with CHECK CONDITION status, with the sense key
set to ILLEGAL REQUEST, and the additional sense code set to LOGICAL UNIT NOT SUPPORTED.
The device server shall report those devices in the logical unit inventory using the format shown in table 136.
Table 136

REPORT LUNS parameter data format

Bit
Byte

7

0

(MSB)

6

5

...

4

3

2

1

0

LUN LIST LENGTH (N-7)
(LSB)

3
4
...

Reserved

7
LUN list
8
...

LUN [first]

15
...
n-7
...

LUN [last]

n
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LUN LIST LENGTH field
The LUN LIST LENGTH field shall contain the length in bytes of the LUN list that is available to be transferred. The LUN list length is the
number of logical unit numbers in the logical unit inventory multiplied by eight. The relationship between the LUN LIST LENGTH field and
the CDB ALLOCATION LENGTH field is defined in 2.2.6.
3.35

REPORT SUPPORTED OPERATION CODES command

3.35.1

Introduction

The REPORT SUPPORTED OPERATION CODES command requests information on commands the addressed logical unit supports. An
application client may request a list of all operation codes and service actions supported by the logical unit or the command support data
for a specific command.
The REPORT SUPPORTED OPERATION CODES command is a service action of the MAINTENANCE IN command. Additional
MAINTENANCE IN service actions are defined in SCC-2 and in this manual. The MAINTENANCE IN service actions defined in SCC-2
apply only to logical units that return a device type of 0Ch or the SCCS bit set to one in their standard INQUIRY data.
Table 137
Bit
Byte

REPORT SUPPORTED OPERATION CODES command
7

6

5

4

Reserved

1
RCTD

(MSB)

5
6

1

0

SERVICE ACTION (0Ch)
Reserved

REPORTING OPTIONS

REQUESTED OPERATION CODE

3
4

2

OPERATION CODE (A3h)

0

2

3

REQUESTED SERVICE ACTION

(LSB)

(MSB)
ALLOCATION LENGTH

...

(LSB)

9
10

Reserved

11

CONTROL

RCTD (Return Command Timeouts Descriptor)
0

A RCTD bit set to zero specifies that the command timeouts descriptor shall not be included in any parameter data returned.

1

A RCTD bit set to one specifies that the command timeouts descriptor shall be included in each command descriptor that is
returned or in the one-command parameter that is returned.

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REPORTING OPTIONS field
The REPORTING OPTIONS field specifies the information to be returned in the parameter data.
Table 138

REPORTING OPTIONS field
Parameter Data
Reference

Code

Descriptions

000b

A list of all operation codes and service actions supported by the logical unit shall be returned
in the all_commands parameter data format. The REQUESTED OPERATION CODE CDB field
and REQUESTED SERVICE ACTION CDB field shall be ignored.

3.35.2

001b

The command support data for the operation code specified in the REQUESTED OPERATION
CODE field shall be returned in the one_command parameter data format. The REQUESTED
SERVICE ACTION CDB field shall be ignored. If the REQUESTED OPERATION CODE field
specifies an operation code that has service actions, then the command shall be terminated
with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN CDB.

3.35.3

010b

The command support data for the operation code and service action specified in the
REQUESTED OPERATION CODE CDB field and REQUESTED SERVICE ACTION CDB field
shall be returned in the one_command parameter data format. If the REQUESTED OPERATION CODE CDB field specifies an operation code that does not have service actions, then the
command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN CDB.

3.35.4

011b - 111b

Reserved.

REQUESTED OPERATION CODE field
The REQUESTED OPERATION CODE field specifies the operation code of the command to be returned in the one_command parameter
data format (see 3.35.3).
REQUESTED SERVICE ACTION field
The REQUESTED SERVICE ACTION field specifies the service action of the command to be returned in the one_command parameter
data format.
ALLOCATION LENGTH field
The ALLOCATION LENGTH field is defined in 2.2.6.

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3.35.2

All-commands parameter data format

The REPORT SUPPORTED OPERATION CODES all_commands parameter data format begins with a four-byte header that contains the
length in bytes of the parameter data followed by a list of supported commands. Each command descriptor contains information about a
single supported command CDB (i.e., one operation code and service action combination, or one non-service-action operation code). The
list of command descriptors shall contain all commands supported by the logical unit.
Table 139

All_commands parameter data

Bit
Byte

7

0

(MSB)

6

5

4

3

2

1

0

COMMAND DATA LENGTH (n - 3)

...

(LSB)

3
Command descriptors
4

Command descriptor [first]

...
...
...

Command descriptor [last] (see table 39)

n
The COMMAND DATA LENGTH field indicates the length in bytes of the command descriptor list.
Each command descriptor (see table 140) contains information about a single supported command CDB.
Table 140
Bit
Byte

Command descriptor format
7

6

5

4

3

0

OPERATION CODE

1

Reserved

2

(MSB)

1

SERVICE ACTION

3

0

(LSB)

Reserved

4
Reserved

5
6

2

(MSB)

CTDP
CDB LENGTH

7

SERVACTV

(LSB)

8
...

Command timeouts descriptor, if any (see table 143)

19
OPERATION CODE field
The OPERATION CODE field contains the operation code of a command supported by the logical unit.
SERVICE ACTION field
The SERVICE ACTION field contains a supported service action of the supported operation code indicated by the OPERATION CODE
field. If the operation code indicated in the OPERATION CODE field does not have a service action, the SERVICE ACTION field shall be
set to 00h.

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CTDP (Command Timeouts Descriptor Present) bit
0

A CTDP bit set to zero indicates that the command timeouts descriptor is not included in this command descriptor.

1

A CTDP bit set to one indicates that the command timeouts descriptor is included in this command descriptor.

SERVACTV (Service Action Valid) bit
0

A service action valid (SERVACTV) bit set to zero indicates the operation code indicated by the OPERATION CODE field does not
have service actions and the SERVICE ACTION field contents are reserved.

1

A SERVACTV bit set to one indicates the operation code indicated by the OPERATION CODE field has service actions and the
contents of the SERVICE ACTION field are valid.

CDB LENGTH field
The CDB LENGTH field contains the length of the command CDB in bytes for the operation code indicated in the OPERATION CODE field.
If the SERVACTV bit is set to one, the CDB LENGTH field contains the length in bytes of the command CDB for the OPERATION CODE/
SERVICE ACTION combination.
RCTD (Report Command Timeout Descriptor) bit
0

If the RCTD bit is set to zero, the command timeouts descriptor shall not be included.

1

If the RCTD bit is set to one in the REPORT SUPPORTED OPERATION CODES CDB, the command timeouts descriptor shall be
included.

3.35.3

One_command parameter data format

The REPORT SUPPORTED OPERATION CODES one_command parameter data format contains information about the CDB and a
usage map for bits in the CDB for the command specified by the REPORTING OPTIONS, REQUESTED OPERATION CODE, and
REQUESTED SERVICE ACTION fields in the REPORT SUPPORTED OPERATION CODES CDB.
Table 141
Bit
Byte

One_command parameter data
7

6

5

4

3

2

1

0

Reserved

0
1

CTDP

2

(MSB)

Reserved

SUPPORT
CDB SIZE (n - 3)

3

(LSB)

4
CDB USAGE DATA

...
n
n+1

Command timeouts descriptor, if any (see table 143)

...
n+12

CTDP (Command Timeout Descriptor Present) bit
0

A CTDP bit set to zero indicates that the command timeouts descriptor is not included in the parameter data.

1

A CTDP bit set to one indicates that the command timeouts descriptor is included in the parameter data.

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SUPPORT field
The SUPPORT field is defined in table 142.
Table 142

SUPPORT values

Support

Description

000b

Data about the requested SCSI command is not currently available. All data after byte 1 is not valid. A
subsequent request for command support data may be successful.

001b

The device server does not support the requested command. All data after byte 1 is undefined.

010b

Reserved.

011b

The device server supports the requested command in conformance with a SCSI standard. The
parameter data format conforms to the definition in table 141.

100b

Reserved.

101b

The device server supports the requested command in a vendor specific manner. The parameter data
format conforms to the definition in table 141.

110b - 111b

Reserved.

CDB SIZE field
The CDB SIZE field contains the size of the CDB USAGE DATA field in the parameter data, and the number of bytes in the CDB for command being queried (i.e., the command specified by the REPORTING OPTIONS, REQUESTED OPERATION CODE, and REQUESTED
SERVICE ACTION fields in the REPORT SUPPORTED OPERATION CODES CDB).
CDB USAGE DATA field
The CDB USAGE DATA field contains information about the CDB for the command being queried. The first byte of the CDB USAGE DATA
field shall contain the operation code for the command being queried. If the command being queried contains a service action, then that
service action code shall be placed in the CDB USAGE DATA field in the same location as the SERVICE ACTION field of the command
CDB. All other bytes of the CDB USAGE DATA field shall contain a usage map for bits in the CDB for the command being queried.
The bits in the usage map shall have a one-for-one correspondence to the CDB for the command being queried. If the device server evaluated a bit in the CDB for the command being queried, the usage map shall contain a one in the corresponding bit position. If any bit representing part of a field is returned as one, all bits for the field shall be returned as one. If the device server ignores or treats as reserved a
bit in the CDB for the command being queried, the usage map shall contain a zero in the corresponding bit position. The usage map bits for
a given CDB field all shall have the same value.
FOr example, the CDB usage bit map for the REPORT SUPPORTED OPERATION CODES command is: A3h, 0Ch, 87h, FFh, FFh, FFh,
FFh, FFh, FFh, FFh, 00h, 07h. This example assumes that the logical unit only supports the low-order three bits of the CDB CONTROL
byte. The first byte contains the operation code, and the second byte contains three reserved bits and the service action. The remaining
bytes contain the usage map.
RCTD (Report Command Timeout Descriptor) bit
0

If the RCTD bit is set to zero, the command timeouts descriptor shall not be included.

1

If the RCTD bit is set to one in the REPORT SUPPORTED OPERATION CODES CDB, the command timeouts descriptor shall be
included.

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3.35.4

Command timeouts descriptor

3.35.4.1

Overview

The command timeouts descriptor (see table 143) returns timeout information for commands supported by the logical unit based on the
time from the start of processing for the command to its reported completion.
Values returned in the command timeouts descriptor do not include times that are outside the control of the device server (e.g., prior
commands with the IMMED bit set to one in the CDB, concurrent commands from the same or different I_T nexuses, manual unloads,
power-on self tests, prior aborted commands, commands that force cache synchronization, delays in the service delivery subsystem).
For commands that cause a change in power condition, values returned in the command timeouts descriptor do not include the power
condition transition time (e.g., the time to spinup rotating media).
Values returned in the command timeouts descriptor should not be used to compare products.
Table 143

Command timeouts descriptor format

Bit
Byte

7

0

(MSB)

6

5

4

3

2

1

DESCRIPTOR LENGTH (000Ah)

1
2

Reserved

3

COMMAND SPECIFIC

0

(LSB)

(MSB)

4

NOMINAL COMMAND PROCESSING TIMEOUT

...

(LSB)

7
(MSB)

8

RECOMMEND COMMAND TIMEOUT

...

(LSB)

11
DESCRIPTOR LENGTH field
The DESCRIPTOR LENGTH field indicates the number of bytes that follow in the command timeouts descriptor.
COMMAND SPECIFIC field

The COMMAND SPECIFIC field contains timeout information (see table 144) that is specific to one or more commands. If no command
specific timeout information is defined by this or the applicable command standard the COMMAND SPECIFIC field is reserved.
Table 144

Command timeout descriptor COMMAND SPECIFIC field usage in this manual

Command

Reference

WRITE BUFFER

3.35.4.2

NOMINAL COMMAND PROCESSING TIMEOUT field
A non-zero value in the NOMINAL COMMAND PROCESSING TIMEOUT field indicates the minimum amount of time in seconds the application client should wait prior to querying for the progress of the command identified by the parameter data that contains this command
timeouts descriptor. A value of zero in the NOMINAL COMMAND PROCESSING TIMEOUT field indicates that no timeout is indicated.
Note.

The value contained in the NOMINAL COMMAND PROCESSING TIMEOUT field may include time required for typical device
error recovery procedures expected to occur on a regular basis.

RECOMMENDED COMMAND TIMEOUT field
A non-zero value in the RECOMMENDED COMMAND TIMEOUT field specifies the recommended time in seconds the application client
should wait prior to timing out the command identified by the parameter data that contains this command timeouts descriptor. A value of
zero in the RECOMMENDED COMMAND TIMEOUT field indicates that no time is indicated.
The device server should set the recommended command timeout to a value greater than or equal to the nominal command processing
timeout.
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3.35.4.2

WRITE BUFFER command timeouts descriptor COMMAND SPECIFIC field usage

For the WRITE BUFFER command, the COMMAND SPECIFIC field usage is reserved for all modes except the following:
a. Download microcode mode (04h);
b. Download microcode and save mode (05h);
c. Download microcode with offsets mode (06h);
d. Download microcode with offsets and save mode (07h);
e. Download microcode with offsets and defer activation mode (0Eh) only if the microcode is activated by an event other than an activate
deferred microcode mode; and
f. Activate deferred microcode mode (0Fh).
If the command timeouts descriptor describes one of the WRITE BUFFER modes listed in this subclause, then the COMMAND SPECIFIC
field indicates the maximum time, in one second increments, that access to the SCSI device is limited or not possible through any SCSI
ports associated with a logical unit that processes a WRITE BUFFER command that specifies one of the named modes. A value of zero in
the COMMAND SPECIFIC field indicates that the no maximum time is indicated.

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3.36

REPORT SUPPORTED TASK MANAGEMENT FUNCTIONS commands

The REPORT SUPPORTED TASK MANAGEMENT FUNCTIONS command requests information on task management functions (see
SAM-5) the addressed logical unit supports.
The REPORT SUPPORTED TASK MANAGEMENT FUNCTIONS command is a service action of the MAINTENTANCE IN command.
Additional MAINTENANCE IN service actions are defined in SCC-2 and this manual. The MAINTENANCE IN service actions defined in
SCC-2 apply only to logical units that return a device type of OCh or the SCCS bit set to one in their standard INQUIRY data (see 3.6.2).
Table 145
Bit
Byte

REPORT SUPPORTED TASK MANAGEMENT FUNCTIONS command
7

6

5

4

3

2

1

0

OPERATION CODE (A3h)

0
Reserved

1

SERVICE ACTION (0Dh)

REPD

2

Reserved

...
5
(MSB)

6

ALLOCATION LENGTH (4h or larger)

...

(LSB)

9
10

Reserved

11

CONTROL

REPD bit
1

A return extended parameter data (REPD) bit set to one specifies that the task management timeout information shall be included
in the parameter data that is returned.

0

A REPD bit set to zero specifies that the task management timeout information shall not be returned.

ALLOCATION LENGTH field
The ALLOCATION LENGTH field (see 2.2.6) specifies the number of bytes that have been allocated for the returned parameter data. The
allocation length should be at least four. If the allocation length is less than four, the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN CDB.
The format of the parameter data returned by the REPORT TASK MANAGEMENT FUNCTIONS command is shown in table 146.
Table 146

REPORT SUPPORTED TASK MANAGEMENT FUNCTIONS parameter data

Bit
Byte

7

6

5

4

3

2

1

0

0

ATS

ATSS

CACAS

CTSS

LURS

QTS

TRS

WAKES

QAES

QTSS

ITNRS

1

Reserved

2

Reserved

3

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The REPORT SUPPORTED TASK MANAGEMENT FUNCTIONS extended parameter data format is shown in Table 147.
Table 147
Bit
Byte
0
1
2
3
4
5
6
7
8
...
11
12
...

REPORT SUPPORTED TASK MANAGEMENT FUNCTIONS extended parameter data
7

6

5

4

3

2

1

0

ATS

ATSS

CACAS
Reserved

CTSS

LURS

QTS
QAES

TRS
QTSS

WAKES
ITNRS

Reserved
REPORT SUPPORTED TASK MANAGEMENT FUNCTIONS ADDITIONAL DATA LENGTH (0Ch)
Reserved
TMFTMOV
Reserved
ATS
ATSTS
CACATS
CTSTS
LURTS
QTTS
Reserved
Reserved
Reserved
QAETS
QTSTS
ITNRTS
(MSB)
TASK MANAGEMENT FUNCTIONS LONG TIMEOUT
(LSB)
(MSB)
TASK MANAGEMENT FUNCTIONS SHORT TIMEOUT
(LSB)

15
ATS (ABORT TASK Supported) bit

1
0

An ATS bit set to one indicates the ABORT TASK task management functions (see SAM-5) is supported by the logical unit
An ATS bit set to zero indicates the ABORT TASK task management function is not supported.

ATSS (ABORT TASK Set Supported) bit

1
0

ATS bit set to one indicates the ABORT TASK SET task management function (see SAM-5) is supported by the logical unit.
ATS bit set to zero indicates the ABORT TASK SET task management function is not supported.

CACAS (CLEAR ACA Supported) bit

1
0

A CACAS bit set to one indicates the CLEAR ACA task management function (see SAM-5) is supported by the logical unit.
A CACAS bit set to zero indicates the CLEAR ACA task management function is not supported.

CTSS (CLEAR TASK SET Supported) bit

1
0

A CTSS bit set to one indicates the CLEAR TASK SET task management function (see SAM-5) is supported by the logical unit.
A CTSS bit set to zero indicates the CLEAR TASK SET task management function is not supported.

LURS (LOGICAL UNIT RESET Supported) bit

1

A LURS bit set to one indicates the LOGICAL UNIT RESET task management function (see SAM-5) is supported by the logical
unit.

0

A LURS bit set to zero indicates the LOGICAL UNIT RESET task management function is not supported.

QTS (QUERY TASK Supported) bit

1
0

A QTS bit set to one indicates the QUERY TASK task management function (see SAM-5) is supported by the logical unit.
A QTS bit set to zero indicates the QUERY TASK task management function is not supported.

TRS (TARGET RESET Supported) bit

1
0

A TRS bit set to one indicates the TARGET RESET task management function (See SAM-2) is supported by the logical unit.
A TRS bit set to zero indicates the TARGET RESET task management function is not supported.

WAKES (WAKEUP Supported) bit

1
0

A WAKES bit set to one indicates the WAKEUP task management function (see SAM-2) is supported by the logical unit.
A WAKES bit set to zero indicates the WAKEUP task management function is not supported.

QAES (QUERY ASYNCHRONOUS EVENT Supported) bit

1

A QAES bit set to one indicates the QUERY ASYNCHRONOUS EVENT task management function (see SAM-5) is supported by
the logical unit.

0

A QAES bit set to zero indicates the QUERY ASYNCHRONOUS EVENT task management function is not supported.

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QTSS (QUERY TASK SET Supported) bit

1

A QUERY TASK SET supported (QTSS) bit set to one indicates the QUERY TASK SET task management function (see SAM-5) is
supported by the logical unit.

0

A QTSS bit set to zero indicates the QUERY TASK SET task management function is not supported.

ITNRS (I-T NEXUS RESET Supported) bit

1
0

An ITNRS bit set to one indicates the I_T NEXUS RESET task management function (see SAM-5) is supported by the logical unit.
An ITNRS bit set to zero indicates the I_T NEXUS RESET task management function is not supported.

TMFTMOV (Task Management Function Timeouts Valid) bit
1

A TMFTMOV bit set to one indicates the contents of the TASK MANAGEMENT FUNCTIONS SHORT TIMEOUT field and TASK
MANAGEMENT FUNCTIONS LONG TIMEOUT field are valid.

0

A TMFTMOV bit set to zero indicates the contents of the TASK MANAGEMENT FUNCTIONS SHORT TIMEOUT field and TASK
MANAGEMENT FUNCTIONS LONG TIMEOUT field are not valid and should be ignored.

ATTS (ABORT TASK Timeout Selector) bit
1

An ATTS bit set to one indicates that the value in the TASK MANAGEMENT FUNCTIONS SHORT TIMEOUT field applies to the
ABORT TASK task management function.

0

An ATTS bit set to zero indicates that the value in the TASK MANAGEMENT FUNCTIONS LONG TIMEOUT field applies to the
ABORT TASK task management function.

ATSTS (ABORT TASK SET Timeout Selector) bit
1

An ATSTS)bit set to one indicates that the value in the TASK MANAGEMENT FUNCTIONS SHORT TIMEOUT field applies to the
ABORT TASK SET task management function.

0

An ATSTS bit set to zero indicates that the value in the TASK MANAGEMENT FUNCTIONS LONG TIMEOUT field applies to the
ABORT TASK SET task management function.

CACATS (CLEAR ACA Timeout Selector) bit
1

A CACATS bit set to one indicates that the value in the TASK MANAGEMENT FUNCTIONS SHORT TIMEOUT field applies to the
CLEAR ACA task management function.

0

A CACATS bit set to zero indicates that the value in the TASK MANAGEMENT FUNCTIONS LONG TIMEOUT field applies to the
CLEAR ACA task management function.

CTSTS (CLEAR TASK SET Timeout Selector) bit
1

A CTSTS bit set to one indicates that the value in the TASK MANAGEMENT FUNCTIONS SHORT TIMEOUT field applies to the
CLEAR TASK SET task management function.

0

A CTSTS bit set to zero indicates that the value in the TASK MANAGEMENT FUNCTIONS LONG TIMEOUT field applies to the
CLEAR TASK SET task management function.

LURTS (LOGICAL UNIT RESET Timeout Selector) bit
1

A LURTS bit set to one indicates that the value in the TASK MANAGEMENT FUNCTIONS SHORT TIMEOUT field applies to the
LOGICAL UNIT RESET task management function.

0

A LURTS bit set to zero indicates that the value in the TASK MANAGEMENT FUNCTIONS LONG TIMEOUT field applies to the
LOGICAL UNIT RESET task management function.

QTTS (QUERY TASK Timeout Selector) bit
1

A QTTS bit set to one indicates that the value in the TASK MANAGEMENT FUNCTIONS SHORT TIMEOUT field applies to the
QUERY TASK task management function.

0

A QTTS bit set to zero indicates that the value in the TASK MANAGEMENT FUNCTIONS LONG TIMEOUT field applies to the
QUERY TASK task management function.

QAETS (QUERY ASYNCHRONOUS EVENT Timeout Selector) bit
1

A QAETS bit set to one indicates that the value in the TASK MANAGEMENT FUNCTIONS SHORT TIMEOUT field applies to the
QUERY ASYNCHRONOUS EVENT task management function.

0

A QAETS bit set to zero indicates that the value in the TASK MANAGEMENT FUNCTIONS LONG TIMEOUT field applies to the
QUERY ASYNCHRONOUS EVENT task management function.

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QTSTS (QUERY TASK SET Timeout Selector) bit
1

A QTSTS bit set to one indicates that the value in the TASK MANAGEMENT FUNCTIONS SHORT TIMEOUT field applies to the
QUERY TASK SET task management function.

0

A QTSTS bit set to zero indicates that the value in the TASK MANAGEMENT FUNCTIONS LONG TIMEOUT field applies to the
QUERY TASK SET task management function.

ITNRTS (I_T NEXUS RESET timeout selector) bit
1

An ITNRTS bit set to one indicates that the value in the TASK MANAGEMENT FUNCTIONS SHORT TIMEOUT field applies to the
I_T NEXUS RESET task management function.

0

An ITNRTS bit set to zero indicates that the value in the TASK MANAGEMENT FUNCTIONS LONG TIMEOUT field applies to the
I_T NEXUS RESET task management function.

TASK MANAGEMENT FUNCTIONS LONG TIMEOUT field
If the TMFTMOV bit is set to one and the TASK MANAGEMENT FUNCTIONS LONG TIMEOUT field is not set to zero, then the contents of
the TASK MANAGEMENT FUNCTIONS LONG TIMEOUT field indicate the recommended time in 100 millisecond increments that the
application client should wait prior to timing out a task management function for which the applicable selector bit is set to zero. If the TMFTMOV bit is set to zero or the TASK MANAGEMENT FUNCTIONS LONG TIMEOUT field is set to zero, then the recommended timeout is
unspecified for any task management function for which the applicable selector bit is set to zero.
TASK MANAGEMENT FUNCTIONS SHORT TIMEOUT field
If the TMFTMOV bit is set to one and the TASK MANAGEMENT FUNCTIONS SHORT TIMEOUT field is not set to zero, then the contents
of the TASK MANAGEMENT FUNCTIONS SHORT TIMEOUT field indicate the recommended time in 100 millisecond increments that the
application client should wait prior to timing out a task management function for which the applicable selector bit is set to one. If the TMFTMOV bit is set to zero or the TASK MANAGEMENT FUNCTIONS SHORT TIMEOUT field is set to zero, then the recommended timeout is
unspecified for any task management function for which the applicable selector bit is set to one.
3.37

REPORT TIMESTAMP command

The REPORT TIMESTAMP command requests that the device server return the value of the logical unit’s timestamp.
Table 148
Bit
Byte

REPORT TIMESTAMP command
7

6

5

4

3

2

1

0

OPERATION CODE (A3h)

0
Reserved

1

SERVICE ACTION (0Fh)

2
Reserved

...
5
6

(MSB)

...

ALLOCATION LENGTH
(LSB)

9
10

Reserved

11

CONTROL

ALLOCATION LENGTH field
The ALLOCATION LENGTH field is defined in 2.2.6.

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The format for the parameter data returned by the REPORT TIMESTAMP command is shown in table 149.
Table 149

REPORT TIMESTAMP parameter data format

Bit
Byte

7

0

(MSB)

6

5

4

3

2

1

9

TIMESTAMP PARAMETER DATA LENGTH (0Ah)

1

Reserved

2

(LSB)

TIMESTAMP ORIGIN
Reserved

3
4

TIMESTAMP

...
9
10

Reserved

11

Rerserved

TIMESTAMP DATA LENGTH field
The TIMESTAMP DATA LENGTH field indicates the number of bytes of parameter data that follow. The relationship between the TIMESTAMP PARAMETER DATA LENGTH field and the CDB ALLOCATION LENGTH field is defined in 2.2.6.
TIMESTAMP ORIGIN field
The TIMESTAMP ORIGIN field indicates the origin of the timestamp (see SPC-4).
TIMESTAMP field
The TIMESTAMP field contains the current value of the timestamp (see SPC-4).
3.38

REQUEST SENSE command

The REQUEST SENSE command (see table 150) requests that the device server transfer sense data to the application client.
Table 150
Bit
Byte

REQUEST SENSE command
7

6

5

4

3

2

1

0

OPERATION CODE (03h)

0

Reserved

1

DESC

Reserved

2
3
4

ALLOCATION LENGTH

5

CONTROL

DESC (Descriptor Format) bit
The descriptor format (DESC) bit specifies which sense data format shall be returned.
0

If DESC is set to zero, fixed format sense data shall be returned (see 2.4.1.2).

1

If DESC is set to one and descriptor format sense data is supported, descriptor format sense data shall be returned (see 2.4.1.1).

Note.

If DESC is set to one and the descriptor format sense data is not supported, Seagate drives terminate the command with
CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID
FIELD IN CDB.

ALLOCATION LENGTH field
The ALLOCATION LENGTH field is defined in 2.2.6. Application clients should request 252 bytes of sense data to ensure they retrieve all
the sense data. If fewer than 252 bytes are requested, sense data may be lost since the REQUEST SENSE command with any allocation
length clears the sense data.
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CONTROL field
The CONTROL field is described in clause 2.2.7.
Sense data shall be available and cleared under the conditions defined in SAM-5. If the device server has no other sense data available to
return, it shall:
1) return the sense key set to NO SENSE, additional sense code set to NO ADDITIONAL SENSE INFORMATION and;
2) complete the REQUEST SENSE command with GOOD status.
3)
On completion of the command the logical unit shall return to the same power condition that was active before the REQUEST SENSE
command was received. A REQUEST SENSE command shall not reset any power condition timers.
The device server shall return CHECK CONDITION status for a REQUEST SENSE command only to report exception conditions specific
to the REQUEST SENSE command itself.
Examples of conditions that cause a REQUEST SENSE command to return a CHECK CONDITION status are:
a) An invalid field value is detected in the CDB;
b) The device server does not support the REQUEST SENSE command (see 3.38);
c) An unrecovered error is detected by the service delivery subsystem; or
d) A malfunction prevents return of the sense data.
Device servers shall return at least 18 bytes of parameter data in response to a REQUEST SENSE command if the allocation length is 18
or greater and the DESC bit is set to zero. Application clients may determine how much sense data has been returned by examining the
ALLOCATION LENGTH field in the CDB and the ADDITIONAL SENSE LENGTH field in the sense data. Device servers shall not adjust
the additional sense length to reflect truncation if the allocation length is less than the sense data available.
3.39

RESERVE(6) command

This command has been declared obsolete by the T10 committee. However, it is included because it may be implemented on some
products.
The RESERVE(6) command (see table 151) is used to reserve a logical unit. This subclause describes only those instances where the
RESERVE(6) command differs from the RESERVE(10) command. Except for the instances described in this subclause, the RESERVE(6)
command shall function exactly like the RESERVE(10) command (see 3.40).
Table 151
Bit
Byte

RESERVE(6) command
7

6

4

3

2

1

0

OPERATION CODE (16h)

0
1

5

Reserved

2
3
4
5

Obsolete
Obsolete
Obsolete
CONTROL

Obsolete Bits 1 through 4 of Byte 1 provided a method, limited to device addresses 0 through 7, to handle third-party reservations in earlier
versions of the SCSI standard. The obsolete method has been replaced by the RESERVE(10) and RELEASE(10).
Byte 1 Bit 0 and Bytes 2 through 4 provide an obsolete way to reserve extents within a logical unit. The Seagate device server does not
support the feature--if it is set, it will be rejected with an ILLEGAL REQUEST/INVALID BIT IN THE CDB. The Seagate device server
ignores the Obsolete field for the Reservation ID.

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3.40

RESERVE (10) command

This command has been declared obsolete by the T10 committee. However, it is included because it may be implemented on some
products.
3.40.1

RESERVE (10) command introduction

The RESERVE(10) command (see table 152) is used to reserve a logical unit.
Table 152
Bit
Byte

RESERVE (10) Command
7

6

5

4

3

2

0

LONGID

Obsolete

OPERATION CODE (56h)

0
Reserved

1

3RDPTY

Reserved

2

Obsolete

3

THIRD-PARTY DEVICE ID

4

Reserved

5

Reserved

6

Reserved

7

1

(MSB)

8

PARAMETER LIST LENGTH

(LSB)

CONTROL

9

The RESERVE and RELEASE commands provide a basic mechanism for contention resolution in multiple-initiator systems. The thirdparty reservation allows logical units to be reserved for another specified SCSI device. See 5.5.1 for a general description of reservations
and the commands that manage them.
If the RESERVE(10) command is implemented, then the RELEASE(10) also shall be implemented.
Byte 1 Bit 0 and Byte 2 provide an obsolete way to reserve extents within a logical unit. If Byte 1, Bit 0 is equal to one, device servers not
implementing the obsolete capability shall terminate the command with CHECK CONDITION status and the sense key shall be set to
ILLEGAL REQUEST.
3.40.2

Logical unit reservation

Logical unit reservations are mandatory if the RESERVE(10) command is implemented. This command shall request that the entire logical
unit be reserved for the exclusive use of the initiator until the reservation is superseded by another valid RESERVE command from the
same initiator or until released by a RELEASE command from the same initiator that made the reservation, by a TARGET RESET task
management function performed by any initiator, by a hard reset condition, or by a power on cycle. A logical unit reservation shall not be
granted if the logical unit is reserved by another initiator. It shall be permissible for an initiator to reserve a logical unit that is currently
reserved by that initiator. If the LONGID bit or the 3RDPTY bit is zero then the PARAMETER LIST LENGTH field shall be ignored.
If the logical unit is reserved for another initiator, the device server shall return RESERVATION CONFLICT status. After honoring a logical
unit reservation, the device server shall check each newly received command for reservation conflicts.
For multiple port implementations, devices on other ports (i.e., the ports that do not include the initiator to which the reservation has been
granted) also shall be denied access to the logical unit as described in the preceding clause.

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3.40.3

Third-party reservation

Third-party reservations are mandatory if the RESERVE(10) command is implemented. The third-party reservation for the RESERVE(10)
command allows an application client to reserve a logical unit within a logical unit for another SCSI device. This is intended for use in
multiple initiator systems that use the COPY or EXTENDED COPY command.
0

If the third-party (3RDPTY) bit is zero, then a third-party reservation is not requested. If the 3RDPTY bit is zero then the LONGID bit
shall be ignored.

1

If the 3RDPTY bit is one then the device server shall reserve the specified logical unit for the SCSI device specified in the THIRDPARTY DEVICE ID field. Device ID formats are protocol specific. The device server shall preserve the reservation until it is superseded by another valid RESERVE command from the initiator that made the reservation or until it is released by the same initiator,
by a TARGET RESET task management function performed by any initiator, a hard reset condition, or by a power on cycle. The
device server shall ignore any attempt to release the reservation made by any other initiator.

After a third-party reservation has been granted, the initiator that sent the RESERVE command shall be treated like any other initiator.
Reservation conflicts shall occur in all cases where another initiator is not allowed access due to the reservation.
If independent sets of mode parameters are implemented, a third-party reservation shall cause the device server to transfer the set of
mode parameters in effect for the application client that sent the RESERVE command to the mode parameters used for commands from
the third-party device. Any subsequent command issued by the third-party device shall be executed according to the mode parameters in
effect for the application client that sent the RESERVE command.
Note.

This transfer of the mode parameters is applicable to device servers that store mode information independently for different
initiators. This mechanism allows an application client to set the mode parameters of a target for the use of a copy master (i.e.,
the third-party device). The third-party copy master may subsequently issue a MODE SELECT command to modify the mode
parameters.

THIRD-PARTY DEVICE ID field
If the THIRD-PARTY DEVICE ID value associated with the reservation release is smaller than 255, the LONGID bit may be zero and the ID
value sent in the CDB. Device ID formats are protocol specific. If the THIRD-PARTY DEVICE ID is greater than 255, the LONGID bit shall
be one. If the LONGID bit is one, the THIRD-PARTY DEVICE ID field in the CDB shall be ignored. If the LONGID bit is one, the parameter
list length shall be at least eight. If the LONGID bit is one and the parameter list length is less than eight, the device server shall return a
CHECK CONDITION status with a sense key of ILLEGAL REQUEST.
Device servers that support device IDs greater than 255 shall accept commands with LONGID equal to one. Device servers whose
devices IDs are limited to 255 or smaller may reject commands with LONGID equal to one with CHECK CONDITION status and a sense
key of ILLEGAL REQUEST.
If the LONGID bit is one, the parameter list length shall be eight, and the parameter list shall have the format shown in table 153. If the
LONGID bit is one and the parameter list length is not eight, the device server shall return a CHECK CONDITION status with a sense key
of ILLEGAL REQUEST.
Table 153
Bit
Byte

RESERVE(10) ID only parameter list
7

6

5

4

3

2

1

0

0
THIRD-PARTY DEVICE ID

...
7
3.40.4

Superseding reservations

Superseding reservations is mandatory if the RELEASE(10) command is implemented. An application client that holds a current logical
unit reservation may modify that reservation by issuing another RESERVE command to the same logical unit. The superseding RESERVE
command shall release the previous reservation state when the new reservation request is granted. The current reservation shall not be
modified if the superseding reservation request is not granted. If the superseding reservation cannot be granted because of conflicts with a
previous reservation, other than the reservation being superseded, then the device server shall return RESERVATION CONFLICT status.
Note.

Superseding reservations allow the SCSI device ID in a third-party reservation to be changed. This capability is necessary for
certain situations when using the EXTENDED COPY command.

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3.41

REZERO UNIT command

This command has been declared obsolete by the T10 committee. However, it is included because it may be implemented on some
products.
Table 154

REZERO UNIT command (01h)

Bit
Byte

7

6

5

3

2

1

0

OPERATION CODE (01h)

0
1

4

LUN

2

LOGICAL BLOCK ADDRESS MUST BE 0’S

3
4

Reserved

5

CONTROL

The Rezero Unit command (see table 154) requests that the disk drive set its logical block address to zero and return the disk drive read/
write heads to the track (or cylinder) containing Logical Block Zero. This command is intended for systems which disable retries and the
initiator performs error recovery. It is longer than a seek to Logical Block Address zero and should be utilized if seek errors are
encountered.
For systems that support disconnection, the disk drive disconnects when this command is received.
A Rezero Command also causes a thermal compensation to occur and resets the thermal compensation cycle timer back to its start, thus
allowing the host to know when to expect the next thermal compensation to occur. The host can thus prevent critical data transfer
operations from being interrupted at an undesirable time.
For drives that support saved log parameters, the Rezero Unit command will also save log counters to the media and reset the log save
timer back to its start.
LUN (Logical Unit Number) field
Seagate drives only support Logical Unit Number 0.
CONTROL field
The CONTROL field is described in clause 2.2.7.

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3.42

SANITIZE command

3.42.1

SANITIZE command introduction

The SANITIZE command (see table 155) requests that the device server perform a sanitize operation. This command shall be processed
as if it has a HEAD OF QUEUE task attribute.
Table 155

SANITIZE command (48h)

Bit
Byte

7

6

5

4

3

2

1

0

OPERATION CODE (48h)

0
IMMED

1

Reserved

AUSE

SERVICE ACTION

2
Reserved

...
6
(MSB)

7
8

PARAMETER LIST LENGTH

(LSB)

CONTROL

9
OPERATION CODE field

The OPERATION CODE field is defined in SPC-4 and shall be set to the value defined in Table 155.
IMMED bit
0

If the IMMED (immediate) bit is set to zero, then the device server shall return status after the sanitize operation is completed.

1

If the IMMED bit set to one, then the device server shall return status as soon as the CDB and parameter data, if any, have been
validated. The REQUEST SENSE command may be used to poll for progress of the sanitize operation regardless of the value of
the IMMED bit.

AUSE bit
If the allow unrestricted sanitize exit (AUSE) bit is set to one, and the specified sanitize operation fails, then the device server shall process
a subsequent EXIT FAILURE MODE service action as if the previous sanitize operation had completed without error (see Completing a
sanitize operation in SBC-3).
If:
a) the AUSE bit is set to zero in the SANITIZE command that requested a sanitize operation;
b) the specified sanitize operation completes with an error; and
c) a subsequent SANITIZE command with the EXIT FAILURE MODE service action is received,
then the device sever shall terminate the command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and
the additional sense code set to INVALID FIELD IN PARAMETER LIST.
SERVICE ACTION field
The SERVICE ACTION field is defined in Section 3.42.2.
PARAMETER LIST LENGTH field
The PARAMETER LIST LENGTH field specifies the length in bytes of the parameter data that shall be sent from the application client to
the device server. A PARAMETER LIST LENGTH field set to zero specifies that no data shall be transferred.
CONTROL field
The CONTROL field is described in clause 2.2.7.

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3.42.2

SANITIZE service actions

The SANITIZE command service actions are defined in (see table 156). At least one service action shall be supported if the SANITIZE
command is supported. If the specified service action is not supported, then the command shall be terminated with CHECK CONDITION
status with the sense key set to ILLEGAL REQUEST and additional sense code set to INVALID FIELD IN CDB.
Table 156

SANITIZE service action codes

Code

Name

Description

PARAMETER LIST LENGTH
field requirement [1][1]

Reference

01h

OVERWRITE

Perform the overwrite
sanitize method.

Greater than 0004h and less
than logical block length + 5

3.42.3

02h

BLOCK ERASE

Perform the block erase
sanitize method.

Set to 0000h

3.42.4

03h

CRYPTOGRAPHIC
ERASE

Perform the cryptographic
erase sanitize method.

Set to 0000h

3.42.5

1Fh

EXIT FAILURE MODE

Exit the Sanitize failure mode

Set to 0000h

3.45.6

all others

Reserved

[1]If the requirement is not met, then the SANITIZE command is terminated with CHECK CONDITION status
with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN CDB.
3.42.3

SANITIZE command with OVERWRITE service action

3.42.3.1

OVERWRITE service action introduction

The OVERWRITE service action (see table 156) performs a sanitize operation using the overwrite method
(see SBC-3).
3.42.3.2

OVERWRITE service action parameter list

The parameter list format for the OVERWRITE service action is shown in Table 157.
Table 157

OVERWRITE service action parameter list

Bit
Byte

7

0

INVERT

6

5

4

3

TEST

2

1

0

OVERWRITE COUNT
Reserved

1
(MSB)

2
3

INITIALIZATION PATTERN LENGTH (n - 3)

(LSB)

4
INITIALIZATION PATTERN

....
n
INVERT bit
1

The INVERT MULT PASSES bit set to one specifies that the initialization pattern and protection information bytes, if any, shall be
inverted (i.e., each bit XORed with one) between consecutive overwrite passes.

0

The INVERT MULT PASSES bit set to zero specifies that the initialization pattern and protection information bytes, if any, are written as specified in the INITIALIZATION PATTERN field on each overwrite pass.

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TEST field
The TEST field is described in Table 158.
Table 158

TEST field

Code

Description

00b
01b to 11b

Shall not cause any changes in the defined behavior of the SANITIZE command
Vendor specific

OVERWRITE COUNT field
The OVERWRITE COUNT field specifies the number of overwrite passes to be performed. A value of 00h is reserved.
INITIALIZATION PATTERN LENGTH field
The INITIALIZATION PATTERN LENGTH field specifies the length in bytes of the INITIALIZATION PATTERN field. The INITIALIZATION
PATTERN LENGTH field shall be greater than zero and shall not exceed the logical block length. If the INITIALIZATION PATTERN
LENGTH field is set to zero or is greater than the logical block length, then the device server shall terminate the command with CHECK
CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN PARAMETER
LIST.
The INITIALIZATION PATTERN field specifies the data pattern used to write the user data. This data pattern is repeated as necessary to fill
each logical block. For each logical block, the first byte of the user data shall begin with the first byte of the initialization pattern. Protection
information bytes, if any, shall be set to FFFF_FFFF_FFFF_FFFFh.
If the INVERT bit is set to one and:
a) the OVERWRITE COUNT field is an even number, then the pattern used for the first write pass shall consist of:
A) the user data shall be set to the inversion of the INITIALIZATION PATTERN data; and
B) protection information bytes, if any, shall be set to 0000_0000_0000_0000h; or
b) the OVERWRITE COUNT field is an odd number, then the pattern used for the first write pass shall consist of:
A) the user data is set to the INITIALIZATION PATTERN data; and
B) protection information bytes, if any, shall be set to FFFF_FFFF_FFFF_FFFFh.
Following a successful sanitize overwrite service action operation:
a. the medium shall not be format corrupt;
b. protection information, if any, set to FFFF_FFFF_FFFF_FFFFh; and
c.read operations should complete without error.
3.42.4

SANITIZE command with BLOCK ERASE service action

The BLOCK ERASE service action (see table 156) performs a sanitize operation using the block erase method (see SBC-3).
After successful completion of a sanitize block erase, the device server:
a) may terminate commands that perform read operations to mapped LBAs with:
A) CHECK CONDITION status with sense key set to MEDIUM ERROR and the appropriate additional sense code for the condition; or
B) if the logical unit is formatted with protection information, CHECK CONDITION status with sense key set to ABORTED COMMAND and
additional sense code set to one of the protection information check codes shown in Table 91;
and
b) should complete read operations to unmapped LBAs without error. (see SBC-3)

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3.42.5

SANITIZE command with CRYPTOGRAPHIC ERASE service action

The CRYPTOGRAPHIC ERASE service action (see table 156) performs a sanitize operation using the cryptographic erase method (see
SBC-3.
After successful completion of the cryptographic erase operation:
a) if any LBA is mapped and if the logical unit is formatted with protection information, then the device server may terminate read
operations with CHECK CONDITION status with sense key set to ABORTED COMMAND and additional sense code set to one of the
protection information check codes shown in Table 91; and
b) the device server shall process unmapped LBAs as required by logical block provisioning management.
3.42.6

SANITIZE command with EXIT FAILURE MODE service action

The EXIT FAILURE MODE service action (see Table 91) requests that the device server complete a sanitize operation which completed
with an error as if the sanitize operation completed without an error (see SBC-3).
After successful completion of a SANITIZE command with the EXIT FAILURE MODE service action:
a. if any LBA is mapped (see SBC-3), and the logical unit is formatted with protection information, then the device server may terminate
commands that perform read operations to mapped LBAs with CHECK CONDITION status with the sense key set to ABORTED COMMAND and the additional sense code set to one of the codes defined in Table 91; and
b. the device server should complete read operations to unmapped LBAs without error (see SBC-3).
3.43

SECURITY PROTOCOL IN command

3.43.1

Command description

The SECURITY PROTOCOL IN command (see table 159) is used to retrieve security protocol information or the results of one or more
SECURITY PROTOCOL OUT commands.
Table 159
Bit
Byte

SECURITY PROTOCOL IN command
7

6

5

4

3

0

OPERATION CODE (A2h)

1

SECURITY PROTOCOL

2

INC_512

0

Reserved
Reserved

5
6

1

SECURITY PROTOCOL SPECIFIC

3
4

2

(MSB)

...

ALLOCATION LENGTH
(LSB)

9
10

Reserved

11

CONTROL

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SECURITY PROTOCOL field
The SECURITY PROTOCOL field (see table 160) specifies which security protocol is being used.
Table 160

SECURITY PROTOCOL field in SECURITY PROTOCOL IN command

Code

Description

Reference

00h

Security protocol information

3.43.2

01h - 06h

Defined by the TCG

https://www.trustedcomputinggroup.org

07h

CbCS

SPC-4

08h - 1Fh

Reserved

20h

Tape Data Encryption

SSC-3

21h

Data Encryption Configuration

ADC-3

22h - 3Fh

Reserved

40h

SA Creation Capabilities

SPC-4

41h

IKEv2-SCSI

SPC-4

42h to EBh

Reserved

ECh

JEDEC Universal Flash Storage

UFS

EDh

SDcard TrustedFlash Security Systems Specification 1.1.3

http://www.sdcard.org/

EEh

Authentication in Host Attachments of Transient Storage Deices

IEEE 1667

EFh

ATA Device Server Password Security

SAT-3

F0h - FFh

Vendor specific

The contents of the SECURITY PROTOCOL SPECIFIC field depend on the protocol specified by the SECURITY PROTOCOL field (see
table 160).
INC_512 (512 Increment)
0

An INC_512 bit set to zero specifies that the ALLOCATION LENGTH field (see 2.2.6) expresses the number of bytes to be transferred.

1

A 512 increment (INC_512) bit set to one specifies that the ALLOCATION LENGTH field (see 2.2.6) expresses the maximum number of bytes available to receive data in increments of 512 bytes (e.g., a value of one means 512 bytes, two means 1,024 bytes,
etc.). Pad bytes may or may not be appended to meet this length. Pad bytes shall have a value of 00h.

Indications of data overrun or underrun and the mechanism, if any, for processing retries depend on the protocol specified by the
SECURITY PROTOCOL field (see table 160).
Any association between a previous SECURITY PROTOCOL OUT command and the data transferred by a SECURITY PROTOCOL IN
command depends on the protocol specified by the SECURITY PROTOCOL field (see table 161). If the device server has no data to
transfer (e.g., the results for any previous SECURITY PROTOCOL OUT commands are not yet available), the device server may transfer
data indicating it has no other data to transfer.
The format of the data transferred depends on the protocol specified by the SECURITY PROTOCOL field (see table 160).
The device server shall retain data resulting from a SECURITY PROTOCOL OUT command, if any, until one of the following events is
processed:
a. Transfer of the data via a SECURITY PROTOCOL IN command from the same I_T_L nexus as defined by the protocol specified by the
SECURITY PROTOCOL field;
b. Logical unit reset (See SAM-5); or
c. I_T nexus loss (See SAM-5) associated with the I_T nexus that sent the SECURITY PROTOCOL OUT command.
If the data is lost due to one of these events the application client may send a new SECURITY PROTOCOL OUT command to retry the
operation.

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3.43.2

Security protocol information description

3.43.2.1

Overview

The purpose of security protocol information security protocol (i.e., the SECURITY PROTOCOL field set to 00h in a SECURITY
PROTOCOL IN command) is to transfer security protocol related information from the logical unit. A SECURITY PROTOCOL IN command
in which the SECURITY PROTOCOL field is set to 00h is not associated with a previous SECURITY PROTOCOL OUT command and
shall be processed without regard for whether a SECURITY PROTOCOL OUT command has been processed.
If the SECURITY PROTOCOL IN command is supported, the SECURITY PROTOCOL value of 00h shall be supported as defined in this
standard.
3.43.2.2

CDB description

When the SECURITY PROTOCOL field is set to 00h in a SECURITY PROTOCOL IN command, the SECURITY PROTOCOL SPECIFIC
field contains a single numeric value as defined in 161.
Table 161

SECURITY PROTOCOL SPECIFIC field for SECURITY PROTOCOL IN protocol 00h

Code

Description

Support

Reference

0000h

Supported security protocol list

Mandatory

3.43.2.3

0001h

Certificate data

Mandatory

3.43.2.4

0002h

Security compliance information

Optional

3.43.2.4.1

0003h - FFFFh

Reserved

All other CDB fields for SECURITY PROTOCOL IN command shall meet the requirements stated in 3.43.1.
Each time a SECURITY PROTOCOL IN command with the SECURITY PROTOCOL field set to 00h is received, the device server shall
transfer the data defined in 3.43.2 starting with byte 0.

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3.43.2.3

Supported security protocols list description

If the SECURITY PROTOCOL field is set to 00h and the SECURITY PROTOCOL SPECIFIC field is set to 0000h in a SECURITY
PROTOCOL IN command, the parameter data shall have the format shown in table 162.
Table 162
Bit
Byte

Supported security protocols SECURITY PROTOCOL IN parameter data
7

6

5

4

3

2

1

0

0
Reserved

...
5
6
7

(MSB)

SUPPORTED SECURITY PROTOCOL LIST LENGTH (m - 7)

8

SUPPORTED SECURITY PROTOCOL (first) (00h)

...

...

m

SUPPORTED SECURITY PROTOCOL (last)

(LSB)

m+1
...

Pad bytes (optional)

n
SUPPORTED SECURITY PROTOCOL LIST LENGTH field
The SUPPORTED SECURITY PROTOCOL LIST LENGTH field indicates the total length, in bytes, of the supported security protocol list
that follows.
SUPPORTED SECURITY PROTOCOL field
Each SUPPORTED SECURITY PROTOCOL field in the supported security protocols list shall contain one of the security protocol values
supported by the logical unit. The values shall be listed in ascending order starting with 00h.

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3.43.2.4
3.43.2.4.1

Certificate data description
Certificate overview

A certificate is either an X.509 Public Key Certificate or an X.509 Attribute Certificate depending on the capabilities of the logical unit.
If the SECURITY PROTOCOL field is set to 00h and the SECURITY PROTOCOL SPECIFIC field is set to 0001h in a SECURITY
PROTOCOL IN command, the parameter data shall have the format shown in table 163.
Table 163
Bit
Byte

Certificate data SECURITY PROTOCOL IN parameter data
7

6

5

0

3

2

1

0

Reserved

1
2

4

(MSB)

3

CERTIFICATE LENGTH (m - 3)

(LSB)

4
CERTIFICATE

...
m
m+1

Pad bytes (optional)

...
n
CERTIFICATE LENGTH field

The CERTIFICATE LENGTH field indicates the total length, in bytes, of the certificate or certificates that follow. The length may include
more than one certificates. If the device server doesn’t have a certificate to transfer, the CERTIFICATE LENGTH field shall be set to
0000h.
CERTIFICATE field
The contents of the CERTIFICATE field are defined in 3.43.2.4.2 and 3.43.2.4.3.
3.43.2.4.2

Public Key certificate description

RFC 3280 defines the certificate syntax for certificates consistent with X.509v3 Public Key Certificate Specification. Any further restrictions
beyond the requirements of RFC 3280 are yet to be defined by T10.
3.43.2.4.3

Attribute certificate description

FRC 3281 defines the certificate syntax for certificates consistent with X.509v2 Attribute certificate Specification. Any further restrictions
beyond the requirements of RFC 3281 are yet to be defined by T10.

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3.43.2.5
3.43.2.5.1

Security compliance information description
Security compliance information overview

The security compliance information parameter data contains information about security standards that apply to this SCSI target device.
If the SECURITY PROTOCOL field is set to 00h and the SECURITY PROTOCOL SPECIFIC field is set to 0002h in a SECURITY
PROTOCOL IN command, then the parameter data shall have the format shown in
Table 164

Certificate data SECURITY PROTOCOL IN parameter data

Bit
Byte

7

0

(MSB)

...

6

5

4

3

2

1

0

SECURITY COMPLIANCE INFORMATION LENGTH (m-3)
(LSB)

3
4
...

Compliance descriptor [first]
...

...

Compliance descriptor [last]

m
m+1
...

Pad bytes (optional)

n
SECURITY COMPLIANCE INFORMATION LENGTH field
The SECURITY COMPLIANCE INFORMATION LENGTH field indicates the total length, in bytes, of the compliance descriptors that follow.
Each compliance descriptor (see 3.43.2.5.2) contains information about a security standard that applies to this SCSI target device. Compliance descriptors may be returned in any order.
The total data length shall conform to the ALLOCATION LENGTH field requirements (see 2.2.6). Pad bytes may be appended to meet this
length. Pad bytes shall have a value of 00h.

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3.43.2.5.2

Compliance descriptor overview

The format of a compliance descriptor in the security compliance information SECURITY PROTOCOL IN parameter data is shown in table
163.
Table 165

Compliance descriptor format

Bit
Byte

7

0

(MSB)

6

5

4

2

Compliance Descriptor Type

1
2

1

0

(LSB)

Reserved

3
4

3

(MSB)
COMPLIANCE DESCRIPTOR LENGTH (n-3)

...

(LSB)

7
8
Descriptor specific information

...
n
COMPLIANCE DESCRIPTOR TYPE field

The COMPLIANCE DESCRIPTOR TYPE field (see table 514) indicates the format of the descriptor specific information. The security compliance information SECURITY PROTOCOL IN parameter data may contain more than one compliance descriptor with the same value in
the COMPLIANCE DESCRIPTOR TYPE field.
Table 166

INFORMATION TYPE

Code

Description

Content

Reference

0001h

Peripheral device identifying information

FIPS 140-2
FIPS 140-3

3.43.2.5.3

All other

Reserved.

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3.43.2.5.3

FIPS 140 compliance descriptor

The FIPS 140 compliance descriptor (see table 167) contains information that may be used to locate information about a FIPS 140 certificate associated with the SCSI target device. The SCSI target device may or may not be operating in the mode specified by that certificate.
Table 167

FIPS 140 Compliance descriptor

Bit
Byte

7

0

(MSB)

6

5

3

2

Compliance Descriptor Type (0001h)

1
2

1

0

(LSB)

Reserved

3
4

4

(MSB)
COMPLIANCE DESCRIPTOR LENGTH (0000 0208h)

...

(LSB)

7
8

REVISION

9

OVERALL SECURITY LEVEL

10
Reserved

...
15
16

(MSB)
Hardware Version

...

(LSB)

143
144

(MSB)
Version

...

(LSB)

271
272

(MSB)
Module Name

...

(LSB)

527
COMPLIANCE DESCRIPTOR TYPE and COMPLIANCE DESCRIPTOR LENGTH fields

The COMPLIANCE DESCRIPTOR TYPE field and COMPLIANCE DESCRIPTOR LENGTH field are defined in 3.43.2.5.2 and shall be set
as shown in table 167 for the FIPS 140 compliance descriptor.
REVISION field
The REVISION field (see table 516) is an ASCII data field (see SPC-4) that indicates the FIPS 140 revision that applies to the SCSI target
device..
Table 168

REVISION field

Code

Related standard

32h

FIPS 140-2

33h

FIPS 140-3

all others
OVERALL SECURITY LEVEL field
The OVERALL SECURITY LEVEL field is an ASCII data field (see SPC-4) that indicates the FIPS 140 overall security level that is reported
by NIST.
HARDWARE VERSION field
The HARDWARE VERSION field is null terminated, null padded data (see SPC-4) that indicates the version number of the hardware in the
module, as reported by NIST.
VERSION field
The VERSION field is null terminated, null padded data (see SPC-4) that indicates the version number of the firmware or software in the
module, as reported by NIST. The value in the VERSION field is not related to the PRODUCT REVISION LEVEL field of standard
INQUIRY data (see 3.6.2).
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MODULE NAME field
The MODULE NAME field is null terminated, null padded data (see SPC-4) that indicates the name or identifier of the cryptographic module, as reported by NIST.
3.44

SECURITY PROTOCOL OUT command

The SECURITY PROTOCOL OUT command (see table 169) is used to send data to the logical unit. The data sent specifies one or more
operations to be performed by the logical unit. The format and function of the operations depends on the contents of the SECURITY
PROTOCOL field(see table 170). Depending on the protocol specified by the SECURITY PROTOCOL field, the application client may use
the SECURITY PROTOCOL IN command (see 3.43) to retrieve data derived from these operations.
Table 169
Bit
Byte

SECURITY PROTOCOL OUT command
7

6

5

4

3

0

OPERATION CODE (B5h)

1

SECURITY PROTOCOL

2

2

1

0

SECURITY PROTOCOL SPECIFIC

3
INC_512

4

Reserved
Reserved

5
(MSB)

6

TRANSFER LENGTH

...

(LSB)

9
10

Reserved

11

CONTROL

SECURITY PROTOCOL field
The SECURITY PROTOCOL field (see table 170) specifies which security protocol is being used.
Table 170

SECURITY PROTOCOL field in SECURITY PROTOCOL OUT command

Code

Description

00h

Reserved

01h - 06h

Defined by the TCG

https://www.trustedcomputinggroup.org

07h

CbCS

SPC-4

08h - 1Fh

Reserved

20h

Tape Data Encryption

SSC-3

21h

Data Encryption Configuration

ADC-3

22h - 40h

Reserved

41h

IKEv2-SCSI

42h - EBh

Reserved

ECh

JEDEC Universal Flash Storage

UFS

EDh

SDcard TrustedFlash Security Systems Specification

http://www.sdcard.org/

EEh

Authentication in Host Attachments of Transient Storage Devices

IEEE 1667

EFh

ATA Device Server Password Security

SAT-3

F0h - FFh

Vendor specific

Note.

Reference

SPC-4

The SECURITY PROTOCOL SPECIFIC field code values 21h - 2Fh are tentatively reserved for SSC-x uses.

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SECURITY PROTOCOL SPECIFIC field
The contents of the SECURITY PROTOCOL SPECIFIC field depend on the protocol specified by the SECURITY PROTOCOL field (see
table 170).
INC_512 (512 Increment)
0

A INC_512 bit set to zero specifies that the TRANSFER LENGTH field indicates the number of bytes to be transferred.

1

INC_512 bit set to one specifies that the TRANSFER LENGTH field (see 2.2.4) expresses the number of bytes to be transferred in
increments of 512 bytes (e.g., a value of one means 512 bytes, two means 1,024 bytes, etc.). Pad bytes shall be appended as
needed to meet this requirement. Pad bytes shall have a value of 00h.

Any association between a SECURITY PROTOCOL OUT command and a subsequent SECURITY PROTOCOL IN command depends on
the protocol specified by the SECURITY PROTOCOL field (see table 170). Each protocol shall define whether:
a. The device server shall complete the command with GOOD status as soon as it determines the data has been correctly received. An
indication that the dat has been processed is obtained by sending a SECURITY PROTOCOL IN command and receiving the results in
the associated data transfer; or
b. The device server shall complete the command with GOOD status only after the data has been successfully processed and an associated SECURITY PROTOCOL IN command is not required.
The format of the data transferred depends on the protocol specified by the SECURITY PROTOCOL field (see table 170).
3.45

SEEK command

This command has been declared obsolete by the T10 committee. However, it is included because it may be implemented on some
products.
Table 171

SEEK command (0Bh)

Bit
Byte

7

6

5

3

2

1

0

OPERATION CODE (0Bh)

0
1

4

LUN

2
3

MSB
LOGICAL BLOCK ADDRESS

4

Reserved

5

CONTROL

LSB

The Seek command (see table 171) requests that the disk drive seek to the specified logical block address.
For systems which support disconnection, the disk drive disconnects when a valid Seek command is received. The use of this command is
infrequent since all commands involving data transfer to/from the disk drive media contain implied seek addresses.
LUN (Logical Unit Number) field
Seagate drives only support Logical Unit Number 0.
LOGICAL BLOCK ADDRESS field
The maximum Logical Block Address that may be specified for a Seek command is defined in Read Capacity Data (see 3.23.1 and 3.24.1).
See 2.2.3 for the definition of the LOGICAL BLOCK ADDRESS field.
CONTROL field
The CONTROL field is described in clause 2.2.7.

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3.46

SEEK EXTENDED command

This command has been declared obsolete by the T10 committee. However, it is included because it may be implemented on some
products.
Table 172

SEEK command (2Bh)

Bit
Byte

7

6

5

4

3

2

1

0

OPERATION CODE (2Bh)

0
LUN

1
2

Reserved
LOGICAL BLOCK ADDRESS (MSB)

...
...

LOGICAL BLOCK ADDRESS (LSB)

5
6

Reserved

7

Reserved

8

Reserved

9

CONTROL

The Seek Extended command (see table 172) requests that the disk drive seek to the specified logical block address.
This command is implemented with the disk drive specific parameters listed in Table 172.
LUN (Logical Unit Number) field
Seagate drives only support Logical Unit Number 0.
Note.

Byte 1 should be 00h. In the CDB, the LUN must be zero.

LOGICAL BLOCK ADDRESS field
Four byte Logical Address may be specified. The drive will seek to this address when the command is received. The maximum Logical
Block Address that may be specified for a Seek command is defined in Read Capacity Data (see 3.23.1 and 3.24.1). See 2.2.3 for the
definition of the LOGICAL BLOCK ADDRESS field.
CONTROL field
The CONTROL field is described in clause 2.2.7.

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3.47

SEND DIAGNOSTIC command

The SEND DIAGNOSTIC command (see table 173) requests the device server to perform diagnostic operations on the SCSI target
device, on the logical unit, or on both. Logical units that support this command shall implement, at a minimum, the default self-test feature
(i.e., the SELFTEST bit equal to one and a parameter list length of zero).
Table 173

SEND DIAGNOSTIC command

Bit
Byte

7

6

5

0

4

3

2

1

0

SELFTEST

DEVOFFL

UNITOFFL

OPERATION CODE (1Dh)

1

SELF-TEST CODE

2

PF

Reserved
Reserved

3

(MSB)

PARAMETER LIST LENGTH

4
5

(LSB)

CONTROL

SELFTEST bit
1

If the SELFTEST bit is set to one, the SELF-TEST CODE field shall contain 000b.

0

If the SELFTEST bit is set to zero, the contents of SELF-TEST CODE field are specified in table 174.

SELF-TEST CODE field
Table 174
Code

SELF-TEST CODE field
Name

Description
This value shall be used when the SELFTEST bit is set to one, or when the SELFTEST bit is set to
zero and the PF bit is set to one.

000b
001b

Background
short self-test

The device server shall start its short self-test (see SPC-4) in the background mode (see SPC-4).
The PARAMETER LIST LENGTH field shall contain zero.

010b

Background
extended self-test

The device server shall start its extended self-test (see SPC-4) in the background mode (see SPC-4).
The PARAMETER LIST LENGTH field shall contain zero.

011b

Reserved

100b

Abort background
self-test

The device server shall abort the current self-test running in background mode. The PARAMETER
LIST LENGTH field shall contain zero. This value is only valid if a previous SEND DIAGNOSTIC
command specified a background self-test function and that self-test has not completed. If either of
these conditions is not met, the command shall be terminated with CHECK CONDITION status, with
the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN
CDB.

101b

Foreground
short self-test

The device server shall start its short self-test (see SPC-4) in the foreground mode (see SPC-4).
The PARAMETER LIST LENGTH field shall contain zero.

110b

Foreground
extended self-test

The device server shall start its extended self-test (see SPC-4) in the foreground mode (see SPC-4).
The PARAMETER LIST LENGTH field shall contain zero.

111b

Reserved

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PF (page format) bit
A page format (PF) bit set to one specifies that the SEND DIAGNOSTIC parameters and any parameters returned by a following
RECEIVE DIAGNOSTIC RESULTS command with the PCV bit set to zero shall contain a single diagnostic page as defined in
4.1.1.

1

Note.

0

Logical units compliant with previous versions of SPC-4 may transfer more than one diagnostic page in the SEND DIAGNOSTIC command’s parameter list and by doing so may request that more than one diagnostic page be transmitted in the
RECEIVE DIAGNOSTIC RESULTS command’s parameter data.
A PF bit set to zero specifies that all SEND DIAGNOSTIC parameters are vendor specific. If the PARAMETER LIST LENGTH field
is set to zero and the SEND DIAGNOSTIC command is not going to be followed by a corresponding RECEIVE DIAGNOSTIC
RESULTS command with the PCV bit set to zero, then the application client shall set the PF bit to zero. The implementation of the
PF bit is optional.

SELFTEST (Self-test) bit
1

A self-test (SELFTEST) bit set to one specifies that the device server shall perform the logical unit default self-test. If the self-test
successfully passes, the command shall be terminated with GOOD status. If the self-test fails, the command shall be terminated
with CHECK CONDITION status, with the sense key set to HARDWARE ERROR.

0

A SELFTEST bit set to zero specifies that the device server shall perform the diagnostic operation specified by the SELF-TEST
CODE field or in the parameter list. The diagnostic operation may require the device server to return parameter data that contains
diagnostic results. If the return of parameter data is not required, the return of GOOD status indicates successful completion of the
diagnostic operation. If the return of parameter data is required, the device server shall either:
[a] Perform the requested diagnostic operation, prepare the parameter data to be returned and indicate completion by returning
GOOD status. The application client issues a RECEIVE DIAGNOSTIC RESULTS command to recover the parameter data; or
[b] Accept the parameter list, and if no errors are detected in the parameter list, return GOOD status. The requested diagnostic
operation and the preparation of the parameter data to be returned are performed upon receipt of a RECEIVE DIAGNOSTIC
RESULTS command.

UNITOFFL (unit offline) bit
1

A unit offline (UNITOFFL) bit set to one specifies that the device server may perform diagnostic operations that may affect the user
accessible medium on the logical unit (e.g., write operations to the user accessible medium, or repositioning of the medium on
sequential access devices). The device server may ignore the UNITOFFL bit.

0

A UNITOFFL bit set to zero specifies that, after the device server has completed any diagnostic operations specified by the SEND
DIAGNOSTIC command, the user accessible medium shall exhibit no effects resulting from the device server’s processing the
SEND DIAGNOSTIC command that are detectable by any application client. When the SELFTEST bit is set to zero, the UNITOFFL
bit shall be ignored.

DEVOFFL (SCSI target device offline) bit
1

A SCSI target device offline (DEVOFFL) bit set to one grants permission to the device server to perform diagnostic operations that
may affect all the logical units in the SCSI target device (e.g., alteration of reservations, log parameters, or sense data). The device
server may ignore the DEVOFFL bit.

0

A DEVOFFL bit set to zero specifies that, after the device server has completed any diagnostic operations specified by the SEND
DIAGNOSTIC command, no logical unit shall exhibit any effects resulting from the device server’s processing the SEND DIAGNOSTIC command that are detectable by any application client. If the SELFTEST bit is set to zero, the DEVOFFL bit shall be
ignored.

PARAMETER LIST LENGTH field
The PARAMETER LIST LENGTH field specifies the length in bytes of the parameter list that shall be transferred from the application client
Data-Out Buffer to the device server. A parameter list length of zero specifies that no data shall be transferred. This condition shall not be
considered an error. If PF bit is set to one and the specified parameter list length results in the truncation of the diagnostic page (e.g., the
parameter list length does not match the page length specified in the diagnostic page), then the command shall be terminated with CHECK
CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN CDB.
To ensure that the diagnostic command information is not destroyed by a command sent from another I_T nexus, the logical unit should be
reserved.

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3.48

SET IDENTIFYING INFORMATION command

The SET IDENTIFYING INFORMATION command (see table 202) requests that the device server set identifying information in the logical
unit to the value received in the SET IDENTIFYING INFORMATION parameter list. The SET IDENTIFYING INFORMATION command is
an extension to the SET PERIPHERAL DEVICE/COMPONENT DEVICE IDENTIFIER service action of the MAINTENANCE OUT
command defined in SCC-2. Additional MAINTENANCE IN and MAINTENANCE OUT service actions are defined in SCC-2 and in this
standard.
The MAINTENANCE OUT service actions defined only in SCC-2 shall apply only to logical units that return a device type of 0Ch (i.e.,
storage array controller device) or the SCCS bit set to one in their standard INQUIRY data. When a logical unit returns a device type of
0Ch or the SCCS bit set to one in its standard INQUIRY data, the implementation requirements for the SCC-2 MAINTENANCE OUT
service actions shall be as specified in SCC-2. Otherwise the MAINTENANCE OUT service action definitions and implementation
requirements stated in this manual shall apply.
On successful completion of a SET IDENTIFYING INFORMATION command that changes identifying information saved by the logical unit,
the device server shall establish a unit attention condition (see SAM-5) for the initiator port associated with every I_T nexus except the I_T
nexus on which the SET IDENTIFIER command was received, with the additional sense code set to DEVICE IDENTIFIER CHANGED.
Table 175
Bit
Byte

SET IDENTIFYING INFORMATION command
7

6

5

3

2

1

0

OPERATION CODE (A4h)

0
Reserved

1
2

SERVICE ACTION (06h)
Reserved

3
4

RESTRICTED (see SSC-2)

5
6

4

(MSB)

...

PARAMETER LIST LENGTH
(LSB)

9
10
11

INFORMATION TYPE

Reserved

CONTROL

The PARAMETER LIST LENGTH field specifies the length in bytes of the identifying information that shall be transferred from the
application client to the device server. A parameter list length of zero specifies that no data shall be transferred, and that subsequent
REPORT IDENTIFYING INFORMATION commands shall return the INFORMATION LENGTH field set to zero for the specified information
type.

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The INFORMATION TYPE specifies the identifying information type to be set.
Table 176

INFORMATION TYPE code list

Code

Description

0000000b

Peripheral device identifying information.
If the PARAMETER LIST LENGTH field is set to greater than the maximum length of the peripheral device identifying information, the device server shall terminate the command with CHECK
CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code
set to INVALID FIELD IN CDB.

0000010b

Peripheral device text identifying information (see 3.33).
If the PARAMETER LIST LENGTH field is set to a value greater than the maximum length of the
peripheral device text identifying information (see 3.33), the device server shall terminate the
command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the
additional sense code set to INVALID FIELD IN CDB.
If the format of the INFORMATION field is incorrect, the device server shall terminate the command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the
additional sense code set to INVALID FIELD IN PARAMETER LIST.

xxxxxx1b

Restricted (see SCC-2)

All other

Reserved.

The SET IDENTIFYING INFORMATION parameter list (see table 177) contains the identifying information to be set by the device server.
Table 177

SET IDENTIFYING INFORMATION parameter list

Bit
Byte

7

6

5

4

3

2

1

0

0
...

INFORMATION

n
INFORMATION
The INFORMATION field specifies the identifying information to be set for the specified information type (see 3.33).
Upon successful completion of a SET IDENTIFYING INFORMATION command, the identifying information that is saved by the logical unit
shall persist through logical unit resets, hard resets, power loss, I_T nexus losses, media format operations, and media replacement.

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3.49

SET TIMESTAMP command

The SET TIMESTAMP command (see table 178) requests the device server to initialize the timestamp. If the SCSIP bit is set to one or the
TCMOS bit is set to one in the Control Extension mode page. If the SCSIP bit is set to zero, the SET TIMESTAMP command shall be
terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID
FIELD IN CDB.
The SET TIMESTAMP command is a service action of the MAINTENANCE OUT command. Additional MAINTENANCE OUT service
actions are defined in SCC-2 and in this standard. The MAINTENANCE OUT service actions defined only in SCC-2 apply only to logical
units that return a device type of 0Ch or the SCCS bit set to one in their standard INQUIRY data (see 3.6.2).
Table 178
Bit
Byte

SET TIMESTAMP command
7

6

5

4

3

2

1

0

OPERATION CODE (0Fh)

0
Reserved

1

SERVICE ACTION (0Fh)

2
Reserved

...
5
6

(MSB)
PARAMETER LIST LENGTH

...

(LSB)

9
10

Reserved

11

CONTROL

PARAMETER LIST LENGTH field
The PARAMETER LIST LENGTH field specifies the length in bytes of the SET TIMESTAMP parameters that shall be transferred from the
application client to the device server. A parameter list length of zero indicates that no data shall be transferred, and that no change shall
be made to the timestamp.
The format for the parameter data returned by the SET TIMESTAMP command is shown in table 179.
Table 179
Bit
Byte

SET TIMESTAMP parameter data format
7

6

5

4

3

2

1

0

0
...

Reserved

3
4
...

TIMESTAMP

9
10

Reserved

11

Reserved

TIMESTAMP field
The TIMESTAMP field shall contain the initial value of the timestamp. The timestamp should be the number of milliseconds that have
elapsed since midnight, 1 January 1970 UT. If the high order byte in the TIMESTAMP field is greater than F0h, the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID
FIELD IN PARAMETER LIST.
On successful completion of a SET TIMESTAMP command the device server shall generate a unit attention condition for the initiator port
associated with every I_T nexus except the I_T nexus on which the SET TIMESTAMP command was received (see SAM-5), with the
additional sense code set to TIMESTAMP CHANGED.
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3.50

START STOP UNIT command

The START STOP UNIT command (see table 180) requests that the device server change the power condition of the logical unit (see
SBC-3) or load or eject the medium. This includes specifying that the device server enable or disable the direct-access block device for
medium access operations by controlling power conditions and timers.
If a START STOP UNIT command is being processed by the device server, and a subsequent START STOP UNIT command for which the
CDB is validated requests that the logical unit change to a different power condition than was specified by the START STOP UNIT
command being processed, then the device server shall terminate the subsequent START STOP UNIT command with CHECK
CONDITION status with the sense key set to NOT READY and the additional sense code set to LOGICAL UNIT NOT READY, START
STOP UNIT COMMAND IN PROGRESS.
If any deferred downloaded code has been received as a result of a WRITE BUFFER command with the MODE field set to 0Eh (see 3.68),
then that deferred downloaded code shall replace the current operational code.
Table 180
Bit
Byte

START STOP UNIT command
7

6

5

4

3

2

1

0

OPERATION CODE (1Bh)

0

Reserved

1

IMMED

Reserved

2
3

Reserved

4

POWER CONDITION

POWER CONDITION MODIFER
Reserved

NO_ FLUSH

LOEJ

START

CONTROL

5
IMMED (Immediate) bit
0

If the immediate (IMMED) bit is set to zero, then the device server shall return status after the operation is completed.

1

If the IMMED bit set to one, then the device server shall return status as soon as the CDB has been validated.

POWER CONDITION field and POWER CONDITION MODIFIER field
The combinations of values in the POWER CONDITION field and POWER CONDITION MODIFIER field are defined in table 181. If the
POWER CONDITION field field is supported and is set to a value other than 0h, then the START and LOEJ bits shall be ignored.
Table 181

POWER
CONDITION

POWER CONDITION field and POWER CONDITION MODIFIER field
POWER
CONDITION
Name

POWER
CONDITION
Description
MODIFIER
value

0h

START_VALID

0h

Process the START and LOEJ bits.

1h

ACTIVE

0h

Cause the logical unit to transition to the active power condition (see SPC-4).

0h

Cause the logical unit to transition to the idle_a power condition (see SPC-4).

1h

Cause the logical unit to transition to the idle_b power condition (see SPC-4).

2h

IDLE

Cause the logical unit to transition to the idle_c power condition (see SPC-4).
3h

STANDBY

5h

Obsolete

7h

LU_CONTROL

Ah

FORCE_IDLE_0

0h

Cause the logical unit to transition to the standby_z power condition (see SPC-4).

1h

Cause the logical unit to transition to the standby_y power condition (see SPC-4).

0h to Fh

Obsolete

0h

Initialize and start all of the idle condition timers that are enabled (see SPC-4), and
initialize and start all of the standby condition timers that are enabled (see SPC-4).

0h

Force the idle_a condition timer to be set to zero (see SPC-4).

1h

Force the idle_b condition timer to be set to zero (see SPC-4).

2h

Force the idle_c condition timer to be set to zero (see SPC-4).

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Table 181

POWER CONDITION field and POWER CONDITION MODIFIER field

POWER
CONDITION

POWER
CONDITION
Name

Bh

FORCE_STANDBY_0

POWER
CONDITION
Description
MODIFIER
value
0h

Force the standby_z condition timer to be set to zero (see SPC-4).

1h

Force the standby_y condition timer to be set to zero (see SPC-4).

All other combinations

Reserved

If the START STOP UNIT command specifies a power condition that conflicts with an operation in progress (e.g., a background self test),
then, after the START STOP UNIT command completes with GOOD status, the logical unit may not be in the power condition that was
requested by the command.
It is not an error to specify that the logical unit transition to its current power condition.
NO_FLUSH bit
0

If the NO_FLUSH bit is set to zero, then logical units that contain cache shall write all cached logical blocks to the medium (e.g., as
they would do in response to a SYNCHRONIZE CACHE command (see 3.51 and 3.52) with the SYNC_NV bit set to zero, the LOGICAL BLOCK ADDRESS field set to zero, and the NUMBER OF LOGICAL BLOCKS field set to zero) prior to entering into any
power condition that prevents accessing the medium (e.g., before the rotating media spindle motor is stopped during transition to
the stopped power condition).

1

If the NO_FLUSH bit is set to one, then cached logical blocks should not be written to the medium by the logical unit prior to entering into any power condition that prevents accessing the medium.

LOEJ (load eject) bit
0

If the load eject (LOEJ) bit is set to zero, then the logical unit shall take no action regarding loading or ejecting the medium.

1

If the LOEJ bit is set to one, then the logical unit shall unload the medium if the START bit is set to zero. If the LOEJ bit is set to one,
then the logical unit shall load the medium if the START bit is set to one. If the POWER CONDITION field is supported and is set to
a value other than 0h, then the device server shall ignore the LOEJ bit.

START bit
0

1

If the START bit is set to zero, then the device server shall:
a) cause the logical unit to transition to the stopped power condition;
b) stop any idle condition timer that is enabled (see SPC-4); and
c) stop any standby condition timer that is enabled (see SPC-4).
If the START bit set to one, then the device server shall:
comply with requirements defined in SCSI transport protocol standards (e.g., the NOTIFY (ENABLE SPINUP) requirement (see
SAS-3));
2) cause the logical unit to transition to the active power condition;
3) initialize and start any idle condition timer that is enabled; and
4) initialize and start any standby condition timer that is enabled.
1)

If the POWER CONDITION field is supported and is set to a value other than 0h, then the device server shall ignore the START bit

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3.51

SYNCHRONIZE CACHE (10) command

The SYNCHRONIZE CACHE (10) command (see table 182) requests that the device server ensure that the specified logical blocks have
their most recent data values recorded in non-volatile cache and/or on the medium, based on the SYNC_NV bit. Logical blocks include
user data and, if the medium is formatted with protection information enabled, protection information. Logical blocks may or may not be
removed from volatile cache and non-volatile cache as a result of the synchronize cache operation.
Table 182
Bit
Byte
0
1
2
...
5
6
7
8
9

SYNCHRONIZE CACHE (10) command
7

6

5

4

3

2

1

0

SYNC_NV

IMMED

Obsolete

OPERATION CODE (35h)
Reserved
(MSB)
LOGICAL BLOCK ADDRESS
(LSB)
Reserved
(MSB)

GROUP NUMBER
NUMBER OF BLOCKS

(LSB)

CONTROL

OPERATION CODE field
The OPERATION CODE field is defined in SPC-4.
LOGICAL BLOCK ADDRESS field
The LOGICAL BLOCK ADDRESS field specifies the first logical block accessed by this command. If the logical block address exceeds the
capacity of the medium the device server shall terminate the command with CHECK CONDITION status with the sense key set to
ILLEGAL REQUEST and the additional sense code set to LOGICAL BLOCK ADDRESS OUT OF RANGE.
GROUP NUMBER field
The GROUP NUMBER field specifies the group into which attributes associated with the command should be collected. A GROUP NUMBER field set to zero specifies that any attributes associated with the command shall not be collected into any group.
SYNC_NV bit
The SYNC_NV bit (see table 183) specifies whether the device server is required to synchronize volatile and non-volatile caches.
Table 183

SYNC_NV bit
Device server requirement to synchronize logical blocks currently in the

Code
Volatile cache

Non-volatile cache

0

Device server shall synchronize to the medium.

Device server shall synchronize to the medium.

1

If a non-volatile cache is present, device server shall synchronize
to non-volatile cache or the medium. If a non-volatile cache is not No requirement.
present, device server shall synchronize to the medium.

IMMED (Immediate) bit
0

An immediate (IMMED) bit set to zero specifies that the device server shall not return status until the synchronize cache operation
has been completed.

1

An IMMED bit set to one specifies that the device server shall return status as soon as the CDB has been validated. If the IMMED
bit is set to one and the device server does not support the IMMED bit, the device server shall terminate the command with CHECK
CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN CDB.

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If the IMMED bit is set to one and the synchronize cache operation has not completed, then the SYNC_PROG field in the Caching mode
page (see 4.3.8) defines device server behavior (see table 184).
Table 184

SYNC_ PROG field description

Code

Description

00b

The device server shall not terminate commands due to the synchronize cache operation and shall not provide pollable sense
data.

01b

The device server:
a) shall not terminate commands due to the synchronize cache operation; and
b) shall provide pollable sense data with the sense key set to NO SENSE, the additional sense code set to SYNCHRONIZE
CACHE OPERATION IN PROGRESS, and the PROGRESS INDICATION field set to indicate the progress of the synchronize cache operation.

10b

The device server:
a) shall process INQUIRY commands, REPORT LUNS commands, REPORT TARGET PORT GROUPS commands, and
REQUEST SENSE commands;
b) may process commands that do not require resources used for the synchronize cache operation;
c) shall terminate commands that require resources used for the synchronize cache operation with CHECK CONDITION status
with the sense key set to NOT READY, the additional sense code set to LOGICAL UNIT NOT READY, SYNCHRONIZE
CACHE OPERATION IN PROGRESS, and the PROGRESS INDICATION field set to indicate the progress of the synchronize cache operation; and
d) shall provide pollable sense data with the sense key set to NOT READY, the additional sense code set to LOGICAL UNIT
NOT READY, SYNCHRONIZE CACHE OPERATION IN PROGRESS, and the PROGRESS INDICATION field set to indicate
the progress of the synchronize cache operation.

11b

Reserved

LOGICAL BLOCK ADDRESS field
See 2.2.3 for the definition of the LOGICAL BLOCK ADDRESS field.
GROUP NUMBER field
See 2.2.8 for the definition of the GROUP NUMBER field.
NUMBER OF BLOCKS field
The NUMBER OF BLOCKS field specifies the number of logical blocks that shall be synchronized, starting with the logical block specified
by the LOGICAL BLOCK ADDRESS field. A NUMBER OF BLOCKS field set to zero specifies that all logical blocks starting with the one
specified in the LOGICAL BLOCK ADDRESS field to the last logical block on the medium shall be synchronized. If the logical block
address plus the number of blocks exceeds the capacity of the medium, the device server shall terminate the command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to LOGICAL BLOCK ADDRESS OUT OF
RANGE.
A logical block within the range that is not in cache is not considered an error.

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3.52

SYNCHRONIZE CACHE (16) command

The SYNCHRONIZE CACHE (16) command (see table 185) requests that the device server ensure that the specified logical blocks have
their most recent data values recorded in non-volatile cache and/or on the medium, based on the SYNC_NV bit. Logical blocks include
user data and, if the medium is formatted with protection information enabled, protection information. Logical blocks may or may not be
removed from volatile cache and non-volatile cache as a result of the synchronize cache operation.
Table 185
Bit
Byte

SYNCHRONIZE CACHE (16) command
7

6

5

3

2

1

0

SYNC_NV

IMMED

Reserved

OPERATION CODE (91h)

0
Reserved

1
2

4

(MSB)
LOGICAL BLOCK ADDRESS

...

(LSB)

9
10

(MSB)
NUMBER OF BLOCKS

...

(LSB)

13
14

Reserved

15

GROUP NUMBER
CONTROL

See the SYNCHRONIZE CACHE (10) command (see 3.51) for the definitions of the fields in this command.

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3.53

TEST UNIT READY command

The TEST UNIT READY command (see table 186) provides a means to check if the logical unit is ready. This is not a request for a selftest. If the logical unit is able to accept an appropriate medium-access command without returning CHECK CONDITION status, this
command shall return a GOOD status. If the logical unit is unable to become operational or is in a state such that an application client
action (e.g., START UNIT command) is required to make the logical unit ready, the command shall be terminated with CHECK
CONDITION status, with the sense key set to NOT READY.
Table 186
Bit
Byte

TEST UNIT READY command
7

6

5

4

3

2

1

0

OPERATION CODE (00h)

0
1

Reserved

...
4

CONTROL

5

Table 187 defines the suggested GOOD and CHECK CONDITION status responses to the TEST UNIT READY command. Other
conditions, including deferred errors, may result in other responses (e.g., BUSY or RESERVATION CONFLICT status).
Table 187

Preferred TEST UNIT READY responses

Status

Sense Key

GOOD

not applicable

CHECK CONDITION

ILLEGAL REQUEST

CHECK CONDITION

NOT READY

LOGICAL UNIT DOES NOT RESPOND TO SELECTION

CHECK CONDITION

NOT READY

MEDIUM NOT PRESENT

CHECK CONDITION

NOT READY

LOGICAL UNIT NOT READY, CAUSE NOT REPORTABLE

CHECK CONDITION

NOT READY

LOGICAL UNIT IS IN PROCESS OF BECOMING READY

CHECK CONDITION

NOT READY

LOGICAL UNIT NOT READY, INITIALIZING COMMAND
REQUIRED

CHECK CONDITION

NOT READY

LOGICAL UNIT NOT READY, MANUAL INTERVENTION
REQUIRED

CHECK CONDITION

NOT READY

LOGICAL UNIT NOT READY, FORMAT IN PROGRESS

SCSI Commands Reference Manual, Rev. H

Additional Sense Code
not applicable
LOGICAL UNIT NOT SUPPORTED

165

3.54

UNMAP command

3.54.1

UNMAP command overview

The UNMAP command (see table 188) requests that the device server cause one or more LBAs to be unmapped. The UNMAP command
is one of the possible commands that shall be implemented by device servers supporting thin provisioning (see SBC-3).
Table 188

UNMAP command

Bit
Byte

7

6

5

4

3

2

1

0

OPERATION CODE (42h)

0

Reserved

1

ANCHOR

2
Reserved

...
5
Reserved

6
7

(MSB)

8
9

GROUP NUMBER
PARAMETER LIST LENGTH

(LSB)

CONTROL

OPERATION CODE field
The OPERATION CODE field is defined in 2.2.1 and shall be set to the value defined in table 188.
ANCHOR bit
For a thin provisioned logical unit (see SBC-3):
0

an ANCHOR bit set to zero specifies that any LBA on which an unmap operation is performed shall become deallocated.

1

an ANCHOR bit set to one specifies that any LBA on which an unmap operation is performed shall become anchored.

For a resource provisioned logical unit (see SBC-3), any LBA on which an unmap operation is performed shall become anchored (i.e., the
command is processed as if the ANCHOR bit is set to one). If the ANCHOR bit is set to one, and the ANC_SUP bit in the Logical Block
Provisioning VPD page (see 4.4.11) is set to zero, then the device server shall terminate the command with CHECK CONDITION status
with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN CDB.
GROUP NUMBER field
See the Grouping Function (Section 2.2.8) for more information on the GROUP NUMBER field.
PARAMETER LIST LENGTH field
The PARAMETER LIST LENGTH field specifies the length in bytes of the UNMAP parameter data that shall be sent from the application
client to the device server. A PARAMETER LIST LENGTH set to zero specifies that no data shall be sent.
CONTROL field
The CONTROL field is described in clause 2.2.7.

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3.54.2

UNMAP parameter list

The UNMAP parameter list (see table 189) contains the data sent by an application client along with an UNMAP command. Included in the
data are an UNMAP parameter list header and block descriptors for LBA extents to be processed by the device server for the UNMAP
command. The LBAs specified in the block descriptors may contain overlapping extents, and may be in any order.
For each specified LBA:
a)
b)

a mapped LBA should be unmapped (see SBC-3), or may remain mapped; and
an unmapped LBA shall remain unmapped.

Table 189

UNMAP parameter list

Bit
Byte

7

0

(MSB)

6

5

(MSB)

3

3

2

UNMAP DATA LENGTH (n-1)

1
2

4

UNMAP BLOCK DESCRIPTOR DATA LENGTH (n-7)

1

0

(LSB)

(LSB)

4
Reserved

.....
7

UNMAP block descriptors
8
.....

UNMAP block descriptor [first] (see table 190)

23
...
n-15
.....

UNMAP block descriptor [last] (see table 190)

n
UNMAP DATA LENGTH field
The UNMAP DATA LENGTH field specifies the length in bytes of the following data that is available to be transferred from the data-out buffer. The UNMAP DATA LENGTH does not include the number of bytes in the UNMAP DATA LENGTH field.
UNMAP BLOCK DESCRIPTOR DATA LENGTH field
The UNMAP BLOCK DESCRIPTOR DATA LENGTH field specifies the length in bytes of the UNMAP block descriptor data that is available
to be transferred from the data-out buffer. The UNMAP BLOCK DESCRIPTOR DATA LENGTH should be a multiple of 16. If the UNMAP
BLOCK DESCRIPTOR DATA LENGTH is not a multiple of 16, then the last UNMAP block descriptor is incomplete and shall be ignored. If
the UNMAP BLOCK DESCRIPTOR DATA LENGTH is set to zero, then no UNMAP block descriptors are included in the UNMAP parameter data. This condition shall not be considered an error.

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Table 190 defines an UNMAP block descriptor.
Table 190

UNMAP block descriptor

Bit
Byte

7

0

(MSB)

6

5

4

3

1

0

UNMAP LOGICAL BLOCK ADDRESS

.....

(LSB)

7
8

2

(MSB)

....

NUMBER OF LOGICAL BLOCKS
(LSB)

11
12
.....

Reserved

15
UNMAP LOGICAL BLOCK ADDRESS
The UNMAP LOGICAL BLOCK ADDRESS field contains the first LBA of the UNMAP block descriptor to be unmapped.
NUMBER OF LOGICAL BLOCKS field
The NUMBER OF LOGICAL BLOCKS field contains the number of LBAs to be unmapped beginning with the LBA specified by the UNMAP
LOGICAL BLOCK ADDRESS field.
If the NUMBER OF LOGICAL BLOCKS is set to zero, then no LBAs shall be unmapped for this UNMAP block descriptor. This condition
shall not be considered an error.
If the LBA specified by the UNMAP LOGICAL BLOCK ADDRESS field plus the number of logical blocks exceeds the capacity of the
medium, then the device server shall terminate the command with CHECK CONDITION status with the sense key set to ILLEGAL
REQUEST and the additional sense code set to LOGICAL BLOCK ADDRESS OUT OF RANGE.
If the total number of logical blocks specified in the UNMAP block descriptor data exceeds the value indicated in the MAXIMUM UNMAP
LBA COUNT field in the Block Limits VPD page (see 4.4.4), or if the number of UNMAP block descriptors exceeds the value of the
MAXIMUM UNMAP PARAMETER COUNT field in the Block Limits VPD page, then the device server shall terminate the command with
CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN
PARAMETER LIST.

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3.55

VERIFY (10) command

The VERIFY (10) command (see table 191) requests that the device server verify the specified logical block(s) on the medium. Each
logical block includes user data and may include protection information, based on the VRPROTECT field and the medium format.
Table 191
Bit
Byte

VERIFY (10) command
7

6

5

4

3

2

1

0

BYTCHK

Obsolete

OPERATION CODE (2Fh)

0
VRPROTECT

1

DPO

Reserved

(MSB)

2

LOGICAL BLOCK ADDRESS

...

(LSB)

5
6

RESTRICTED
FOR MMC-5

7

(MSB)

Reserved

8

GROUP NUMBER
VERIFICATION LENGTH

(LSB)

CONTROL

9

Logical units that contain cache shall write referenced cached logical blocks to the medium for the logical unit (e.g., as they would do in
response to a SYNCHRONIZE CACHE command (see 3.51 and 3.52) with the SYNC_NV bit set to zero, the LOGICAL BLOCK ADDRESS
field set to the value of the VERIFY command’s LOGICAL BLOCK ADDRESS field, and the NUMBER OF BLOCKS field set to the value of
the VERIFY command’s VERIFICATION LENGTH field).
See the READ (10) command (see 3.18) for the definition of the DPO bit. See 2.2.3 for the definition of the LOGICAL BLOCK ADDRESS
field. See 2.2.8 for the definition of the GROUP NUMBER field.
If the Verify Error Recovery mode page (see 4.3.21) is implemented, then the current settings in that page specify the verification criteria. If
the Verify Error Recovery mode page is not implemented, then the verification criteria is vendor-specific.
BYTCHK bit
0

If the byte check (BYTCHK) bit is set to zero, the device server shall:
a) perform a medium verification with no data comparison and not transfer any data from the data-out buffer; and
b) check protection information read from the medium based on the VRPROTECT field as described in table 192.

If the byte check (BYTCHK) bit is set to zero, then, for any unmapped LBA specified by the command, the device server shall take no
action and consider the LBA as having been verified without error.

1

If the BYTCHK bit is set to one, the device server shall:
a) perform a byte-by-byte comparison of user data read from the medium and user data transferred from the data-out buffer;
b) check protection information read from the medium based on the VRPROTECT field as described in table 193;
c) check protection transferred from the data-out buffer based on the VRPROTECT field as described in table 194; and
d) perform a byte-by-byte comparison of protection information read from the medium and transferred from the data-out buffer
based on the VRPROTECT field as described in table 195.

If the BYTCHK bit is set to one, then, if any unmapped LBA is specified by the command, the device server shall terminate the command
with CHECK CONDITION status with the sense key set to MISCOMPARE and the additional sense code set to MISCOMPARE VERIFY
OF UNMAPPED LBA.
The order of the user data and protection information checks and comparisons is vendor-specific.
If a byte-by-byte comparison is unsuccessful for any reason, the device server shall terminate the command with CHECK CONDITION
status with the sense key set to MISCOMPARE and the additional sense code set to the appropriate value for the condition.
VERIFICATION LENGTH field
The VERIFICATION LENGTH field specifies the number of contiguous logical blocks that shall be verified, starting with the logical block
specified by the LOGICAL BLOCK ADDRESS field. If the BYTCHK bit is set to one, the VERIFICATION LENGTH field also specifies the number
of logical blocks that the device server shall transfer from the data-out buffer. A VERIFICATION LENGTH field set to zero specifies that no logical blocks shall be verified. This condition shall not be considered as an error. Any other value specifies the number of logical blocks that
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shall be verified. If the logical block address plus the verification length exceeds the capacity of the medium, the device server shall terminate the command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to
LOGICAL BLOCK ADDRESS OUT OF RANGE. The VERIFICATION LENGTH field is constrained by the MAXIMUM TRANSFER
LENGTH field in the Block Limits VPD page.
If the BYTCHK bit is set to zero, the device server shall check the protection information read from the medium based on the VRPROTECT
field as described in table 192.
Table 192

Code

VRPROTECT field with BYTCHK set to zero - medium (Sheet 1 of 2)
Logical unit
formatted with
protection
information

Field in
protection
information [g]

Extended INQUIRY
Data VPD page bit
value [f]

LOGICAL BLOCK GRD_CHK = 1
GUARD
GRD_CHK = 0

Yes [i]

000b

LOGICAL BLOCK APP_CHK = 1 [c]
APPLICATION
TAG
APP_CHK = 0
LOGICAL BLOCK REF_CHK = 1 [h]
REFERENCE
TAG
REF_CHK = 0

No

Yes

LOGICAL BLOCK APP_CHK = 1 [c]
APPLICATION
TAG
APP_CHK = 0
LOGICAL BLOCK REF_CHK = 1 [h]
REFERENCE
TAG
REF_CHK = 0

No

Yes

LOGICAL BLOCK APP_CHK = 1 [c]
APPLICATION
TAG
APP_CHK = 0
LOGICAL BLOCK REF_CHK = 1 [h]
REFERENCE
TAG
REF_CHK = 0

No

LOGICAL BLOCK APPLICATION TAG CHECK
FAILED
No check performed
LOGICAL BLOCK REFERENCE TAG CHECK
FAILED
No check performed
LOGICAL BLOCK GUARD CHECK FAILED
No check performed
LOGICAL BLOCK APPLICATION TAG CHECK
FAILED
No check performed
LOGICAL BLOCK REFERENCE TAG CHECK
FAILED
No check performed

No check performed
LOGICAL BLOCK APPLICATION TAG CHECK
FAILED
No check performed
LOGICAL BLOCK REFERENCE TAG CHECK
FAILED
No check performed

Error condition [a]

Yes

011b [b]

No check performed

Error condition [a]
LOGICAL BLOCK
GUARD

010b [b]

LOGICAL BLOCK GUARD CHECK FAILED

No protection information on the medium to check. Only user data is checked.
LOGICAL BLOCK GRD_CHK = 1
GUARD
GRD_CHK = 0

001b
101b [b]

If check fails [d] [e],
additional sense code

LOGICAL BLOCK
GUARD

No check performed

LOGICAL BLOCK
APPLICATION
TAG

No check performed

LOGICAL BLOCK
REFERENCE No check performed
TAG
No

Error condition [a]

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Table 192

Code

VRPROTECT field with BYTCHK set to zero - medium (Sheet 2 of 2)
Logical unit
formatted with
protection
information

Field in
protection
information [g]

Extended INQUIRY
Data VPD page bit
value [f]

LOGICAL BLOCK GRD_CHK = 1
GUARD
GRD_CHK = 0
Yes

100b [b]

No
101b 111b

If check fails [d] [e],
additional sense code
LOGICAL BLOCK GUARD CHECK FAILED
No check performed

LOGICAL BLOCK
APPLICATION
TAG

No check performed

LOGICAL BLOCK
REFERENCE
TAG

No check performed

Error condition [a]

Reserved

[a] A verify operation to a logical unit that supports protection information and has not been formatted with protection information shall be terminated with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the
additional sense code set to INVALID FIELD IN CDB.
[b] If the logical unit does not support protection information the requested command should be terminated with CHECK
CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID
FIELD IN CDB.
[c] If the device server has knowledge of the contents of the LOGICAL BLOCK APPLICATION TAG field, then the device
server shall check each logical block application tag. If the ATO bit in the Control mode page (see 4.3.9) is set to one,
then this knowledge is acquired from:
a. the EXPECTED LOGICAL BLOCK APPLICATION TAG field and the LOGICAL BLOCK APPLICATION TAG MASK
field in the CDB, if a VERIFY (32) command (see 5.32) is received by the device server;
b. the Application Tag mode page (see 4.3.6), if a command other than VERIFY (32) is received by the device server,
and the ATMPE bit in the Control mode page (see 4.3.9) is set to one; or
c. a method not defined by this standard, if a command other than VERIFY (32) is received by the device server, and
the ATMPE bit is set to zero.
[d] If an error is reported, the sense key shall be set to ABORTED COMMAND.
[e] If multiple errors occur, the selection of which error to report is not defined by this manual.
[f] See the Extended INQUIRY Data VPD page (see 4.4.7) for the definitions of the GRD_CHK bit, the APP_CHK bit, and
the REF_CHK bits.
[g] If the application client or device server detects a:
a. LOGICAL BLOCK APPLICATION TAG field set to FFFFh and type 1 protection (see SBC-3) or type 2 protection
(see SBC-3) is enabled; or
b. LOGICAL BLOCK APPLICATION TAG field set to FFFFh, LOGICAL BLOCK REFERENCE TAG field set to
FFFF FFFFh, and type 3 protection (see SBC-3) is enabled,
then the device server shall not check any protection information in the associated logical block.
[h] If type 1 protection is enabled, the device server checks the logical block reference tag by comparing it to the lower 4
bytes of the LBA associated with the logical block. If type 2 protection or type 3 protection is enabled, the device server
checks the logical block reference tag if it has knowledge of the contents of the LOGICAL BLOCK REFERENCE TAG
field. If type 2 protection is enabled, then this knowledge may be acquired through the EXPECTED INITIAL LOGICAL
BLOCK REFERENCE TAG field in a VERIFY (32) command (see 3.58). If type 3 protection is enabled, then the
method for acquiring this knowledge is not defined by this manual.
[i] If the DPICZ bit in the Control mode page (see 4.3.9) is set to one, then protection information shall not be checked.

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If the BYTCHK bit is set to one, the device server shall check the protection information read from the medium based on the VRPROTECT
field as described in table 193.
Table 193

Code

VRPROTECT field with BYTCHK set to one - medium
Extended INQUIRY
Logical unit formatted
Field in protection
Data VPD page bit
with protection
information [g]
information
value [f]

If check fails [d] [e],
additional sense code

LOGICAL BLOCK GRD_CHK = 1
GUARD
GRD_CHK = 0
Yes [i]

000b

LOGICAL BLOCK APP_CHK = 1
APPLICATION TAG APP_CHK = 0

LOGICAL BLOCK GUARD CHECK FAILED
No check performed
LOGICAL BLOCK APPLICATION TAG CHECK FAILED

[c] [g]

No check performed
LOGICAL BLOCK REFERENCE TAG CHECK FAILED

[h]
LOGICAL BLOCK REF_CHK = 1
REFERENCE TAG REF_CHK = 0

No
001b
010b
011b
100b
101b [b]

No check performed

No protection information on the medium available to check

Yes

LOGICAL BLOCK
GUARD

No check performed

LOGICAL BLOCK
APPLICATION TAG

No check performed

LOGICAL BLOCK
REFERENCE TAG

No check performed

No
110b 111b

Error condition [a]
Reserved

[a] A verify operation to a logical unit that supports protection information and has not been formatted with protection information shall be
terminated with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to
INVALID FIELD IN CDB.
[b] If the logical unit does not support protection information the requested command should be terminated with CHECK CONDITION
status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN CDB.
[c] If the device server has knowledge of the contents of the LOGICAL BLOCK APPLICATION TAG field, then the device server shall
check each logical block application tag. If the ATO bit in the Control mode page (see 4.3.9) is set to one, then this knowledge is
acquired from:
a. the EXPECTED LOGICAL BLOCK APPLICATION TAG field and the LOGICAL BLOCK APPLICATION TAG MASK field in the
CDB, if a VERIFY (32) command (see 5.32) is received by the device server;
b. the Application Tag mode page (see 4.3.6) if a command other than VERIFY (32) is received by the device server, and the
ATMPE bit in the Control mode page (see 4.3.9) is set to one; or
c. a method not defined by this standard, if a command other than VERIFY (32) is received by the device server, and the ATMPE bit
is set to zero.
[d] If an error is reported, the sense key shall be set to ABORTED COMMAND.
[e] If multiple errors occur, the selection of which error to report is not defined by this manual.
[f] See the Extended INQUIRY Data VPD page (see 4.4.7) for the definitions of the GRD_CHK bit, the APP_CHK bit, and the REF_CHK
bit.
[g] If the application client or device server detects a:
a. logical block application tag field set to FFFFh and type 1 protection or type 2 protection is enabled; or
b. logical block application tag field set to FFFFh, logical block reference tag field set to FFFF FFFFh, and type 3 protection is
enabled,
then the device server shall not check any protection information in the associated logical block.
[h] If type 1 protection is enabled, the device server checks the logical block reference tag by comparing it to the lower 4 bytes of the
LBA associated with the logical block. If type 2 protection or type 3 protection is enabled, the device server checks the logical block
reference tag if it has knowledge of the contents of the logical block reference tag field. If type 2 protection is enabled, then this
knowledge may be acquired through the expected initial logical block reference tag field in a VERIFY (32) command (see 3.58). If
type 3 protection is enabled, then the method for acquiring this knowledge is not defined by this manual.
[i] If the DPICZ bit in the Control mode page (see 4.3.9) is set to one, then protection information shall not be checked.

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If the BYTCHK bit is set to one, the device server shall check the protection information transferred from the data-out buffer based on the
VRPROTECT field as described in table 194.
Table 194

Code

VRPROTECT field with BYTCHK set to one - data-out buffer (Sheet 1 of 2)
Logical unit
formatted with Field in protection
protection
information
information

Device server
check

Yes

No protection information received from application client to check

No

No protection information received from application client to check

000b

Yes
001b [b]

Yes
[b]

Shall

LOGICAL BLOCK
APPLICATION TAG

May [c]

LOGICAL BLOCK APPLICATION TAG CHECK
FAILED

LOGICAL BLOCK
REFERENCE TAG

Shall [f]

LOGICAL BLOCK REFERENCE TAG CHECK
FAILED
Error condition [a]

Yes
011b

Shall not

LOGICAL BLOCK
APPLICATION TAG

May [c]

LOGICAL BLOCK APPLICATION TAG CHECK
FAILED

LOGICAL BLOCK
REFERENCE TAG

May [f]

LOGICAL BLOCK REFERENCE TAG CHECK
FAILED
Error condition [a]

LOGICAL BLOCK
GUARD

Shall not

No check performed

LOGICAL BLOCK
APPLICATION TAG

Shall not

No check performed

LOGICAL BLOCK
REFERENCE TAG

Shall not

No check performed
Error condition [a]

No

Yes
100b [b]

No check performed

LOGICAL BLOCK
GUARD

No

[b]

LOGICAL BLOCK GUARD CHECK FAILED

LOGICAL BLOCK
GUARD

No

010b

If check fails [d] [e], additional sense code

LOGICAL BLOCK GUARD CHECK FAILED

LOGICAL BLOCK
GUARD

Shall

LOGICAL BLOCK
APPLICATION TAG

Shall not

No check performed

LOGICAL BLOCK
REFERENCE TAG

Shall not

No check performed

No

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Error condition [a]

173

Table 194

Code

VRPROTECT field with BYTCHK set to one - data-out buffer (Sheet 2 of 2)
Logical unit
formatted with Field in protection
protection
information
information

Yes
101b

[b]

Device server
check

If check fails [d] [e], additional sense code

LOGICAL BLOCK
GUARD

Shall

LOGICAL BLOCK GUARD CHECK FAILED

LOGICAL BLOCK
APPLICATION TAG

May [c]

LOGICAL BLOCK APPLICATION TAG CHECK
FAILED

LOGICAL BLOCK
REFERENCE TAG

May [f]

LOGICAL BLOCK REFERENCE TAG CHECK
FAILED

No
110b 111b

Error condition [a]
Reserved

[a] A verify operation to a logical unit that supports protection information and has not been formatted with protection
information shall be terminated with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and
the additional sense code set to INVALID FIELD IN CDB.
[b] If the logical unit does not support protection information the requested command should be terminated with CHECK
CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID
FIELD IN CDB.
[c] If the device server has knowledge of the contents of the LOGICAL BLOCK APPLICATION TAG field, then the
device server shall check each logical block application tag. If the ATO bit in the Control mode page (see 4.3.9) is set
to one, then this knowledge is acquired from:
a. the EXPECTED LOGICAL BLOCK APPLICATION TAG field and the LOGICAL BLOCK APPLICATION TAG
MASK field in the CDB, if a VERIFY (32) command (see 5.32) is received by the device server;
b. the Application Tag mode page (see 4.3.6), if a command other than VERIFY (32) is received by the device
server, and the ATMPE bit in the Control mode page (see 4.3.9) is set to one; or
c. a method not defined by this standard, if a command other than VERIFY (32) is received by the device server,
and the ATMPE bit is set to zero.
[d] If an error is reported, the sense key shall be set to ABORTED COMMAND.
[e] If multiple errors occur, the selection of which error to report is not defined by this manual.
[f]

If type 1 protection is enabled, the device server checks the logical block reference tag by comparing it to the lower
4 bytes of the LBA associated with the logical block. If type 2 protection or type 3 protection is enabled, the device
server checks the logical block reference tag if it has knowledge of the contents of the logical block reference tag
field. If type 2 protection is enabled, then this knowledge may be acquired through the expected initial logical block
reference tag field in a VERIFY (32) command (see 3.58). If type 3 protection is enabled, then the method for acquiring this knowledge is not defined by this manual.

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If the BYTCHK bit is set to one, the device server shall perform a byte-by-byte comparison of protection information transferred from the
data-out buffer with protection information read from the medium based on the VRPROTECT field as described in table 195.
Table 195

Code

VRPROTECT field with BYTCHK set to one - byte-by-byte comparison requirements (Sheet 1 of 2)
Logical unit
formatted with
protection
information

If compare fails [c] [d],
additional sense code

No protection information received from application client to compare. Only user data is
compared within each logical block.

No

No protection information or the medium or received from application client to compare.
Only user data is compared within each logical block.

Yes

No

010b [b]

Byte-by-byte
Comparison

Yes
000b

001b [b]

Field

Yes

No

LOGICAL BLOCK
GUARD

Shall

LOGICAL BLOCK GUARD CHECK FAILED

LOGICAL BLOCK APPLICATION TAG
(ATO = 1) [e]

Shall

LOGICAL BLOCK APPLICATION TAG
CHECK FAILED

LOGICAL BLOCK APPLICATION TAG
(ATO = 0) [f]

Shall not

LOGICAL BLOCK REFERENCE TAG

Shall

LOGICAL BLOCK REFERENCE TAG CHECK
FAILED

LOGICAL BLOCK REFERENCE TAG
(type 3
and ATO = 0)

Shall

LOGICAL BLOCK REFERENCE TAG CHECK
FAILED

LOGICAL BLOCK REFERENCE TAG
(type 3
and ATO = 1)

Shall not

No compare performed

No compare performed

Error condition [a]
LOGICAL BLOCK
GUARD

Shall not

LOGICAL BLOCK APPLICATION TAG
(ATO = 1) [e]

Shall

LOGICAL BLOCK APPLICATION TAG
(ATO = 0) [f]

Shall not

LOGICAL BLOCK REFERENCE TAG
(not type 3)

Shall

LOGICAL BLOCK REFERENCE TAG
(type 3 and ATO = 0

Shall

LOGICAL BLOCK REFERENCE TAG
(type 3 and ATO = 1)

Shall not

No compare performed
LOGICAL BLOCK APPLICATION TAG
CHECK FAILED

No compare performed

LOGICAL BLOCK REFERENCE TAG CHECK
FAILED
LOGICAL BLOCK REFERENCE TAG CHECK
FAILED
No compare performed

Error condition [a]

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175

Table 195

Code

010b [b]
100b

VRPROTECT field with BYTCHK set to one - byte-by-byte comparison requirements (Sheet 2 of 2)
Logical unit
formatted with
protection
information

Yes

No

Yes
101b [b]

No

Field

Byte-by-byte
Comparison

LOGICAL BLOCK
GUARD

Shall

LOGICAL BLOCK APPLICATION TAG
(ATO = 1) [e]

Shall

LOGICAL BLOCK APPLICATION TAG
(ATO = 0) [f]

Shall not

LOGICAL BLOCK REFERENCE TAG
(not type 3)

Shall

LOGICAL BLOCK REFERENCE TAG
(type 3 and ATO = 0

Shall

LOGICAL BLOCK REFERENCE TAG
(type 3 and ATO = 1)

Shall not

If compare fails [c] [d],
additional sense code

LOGICAL BLOCK GUARD CHECK FAILED
LOGICAL BLOCK APPLICATION TAG
CHECK FAILED

No compare performed

LOGICAL BLOCK REFERENCE TAG CHECK
FAILED
LOGICAL BLOCK REFERENCE TAG CHECK
FAILED
No compare performed

Error condition [a]
LOGICAL BLOCK
GUARD

Shall

LOGICAL BLOCK GUARD CHECK FAILED

LOGICAL BLOCK APPLICATION TAG
(ATO = 1) [e]

Shall

LOGICAL BLOCK APPLICATION TAG
CHECK FAILED

LOGICAL BLOCK APPLICATION TAG
(ATO = 0) [f]

Shall not

LOGICAL BLOCK REFERENCE TAG

Shall

No compare performed
LOGICAL BLOCK REFERENCE TAG CHECK
FAILED

Error condition [a]

110b 111b

Reserved

[a] A verify operation to a logical unit that supports protection information and has not been formatted with protection
information shall be terminated with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and
the additional sense code set to INVALID FIELD IN CDB.
[b] If the logical unit does not support protection information the requested command should be terminated with CHECK
CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID
FIELD IN CDB.
[c] If an error is reported, the sense key shall be set to MISCOMPARE.
[d] If multiple errors occur, the selection of which error to report is not defined by this manual.
[e] If the ATO bit is set to one in the Control mode page (see 4.3.9), the logical block application tag shall not be
modified by a device server.
[f] If the ATO bit is set to zero in the Control mode page (see 4.3.9), the logical block application tag may be modified by
a device server.

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3.56

VERIFY (12) command

The VERIFY (12) command (see table 196) requests that the device server verify the specified logical block(s) on the medium. Each
logical block includes user data and may include protection information, based on the VRPROTECT field and the medium format.
Table 196
Bit
Byte

VERIFY (12) command
7

6

5

0

4

3

2

1

0

BYTCHK

Obsolete

OPERATION CODE (AFh)

1

VRPROTECT

2

DPO

Reserved

(MSB)
LOGICAL BLOCK ADDRESS

...
5

(LSB)

6

(MSB)
VERIFICATION LENGTH

...
9

(LSB)

10

Restricted
For MMC-5

Reserved

GROUP NUMBER

11

CONTROL

See the VERIFY (10) command (see 3.55) for the definitions of the fields in this command.
3.57

VERIFY (16) command

The VERIFY (16) command (see table 197) requests that the device server verify the specified logical block(s) on the medium. Each
logical block includes user data and may include protection information, based on the VRPROTECT field and the medium format.
Table 197
Bit
Byte

VERIFY (16) command
7

6

5

3

2

1

0

BYTCHK

Reserved

OPERATION CODE (8Fh)

0
VRPROTECT

1
2

4

DPO

Reserved

(MSB)
LOGICAL BLOCK ADDRESS

...

(LSB)

9
10

(MSB)
VERIFICATION LENGTH

...

(LSB)

13
14

Restricted
for MMC-5

Reserved

GROUP NUMBER
CONTROL

15

See the VERIFY (10) command (see 3.55) for the definitions of the fields in this command.
3.58

VERIFY (32) command

The VERIFY (32) command (see table 198) requests that the device server verify the specified logical block(s) on the medium. Each
logical block includes user data and may include protection information, based on the VRPROTECT field and the medium format.

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The VERIFY (32) command shall only be processed if type 2 protection is enabled (see SPC-4).
Table 198
Bit
Byte
0
1
2
...
5
6
7
8
9
10
11
12
...
19
20
...
23
24
25
26
27
28
...
31

VERIFY (32) command
7

6

5

4

3

2

1

0

BYTCHK

(LSB)
Reserved

OPERATION CODE (7Fh)
CONTROL
Reserved
Reserved

GROUP NUMBER
ADDITIONAL CDB LENGTH (18h)

(MSB)

SERVICE ACTION (000Ah)
VRPROTECT

DPO

Reserved
Reserved

(MSB)
LOGICAL BLOCK ADDRESS
(LSB)
(MSB)
EXPECTED INITIAL LOGICAL BLOCK REFERENCE TAG
(LSB)
(MSB)

EXPECTED LOGICAL BLOCK APPLICATION TAG

(MSB)

LOGICAL BLOCK APPLICATION TAG MASK

(LSB)
(LSB)

(MSB)
VERIFICATION LENGTH
(LSB)

See the VERIFY (10) command (see 3.55) for the definitions of the GROUP NUMBER field, VRPROTECT field, DPO bit, BYTCHK bit,
LOGICAL BLOCK ADDRESS field, and VERIFICATION LENGTH field.
When checking of the LOGICAL BLOCK REFERENCE TAG field is enabled (see table 192, table 193, table 194, and table 195 in 3.55),
the EXPECTED INITIAL LOGICAL BLOCK REFERENCE TAG field contains the value of the LOGICAL BLOCK REFERENCE TAG field
expected in the protection information of the first logical block accessed by the command instead of a value based on the LBA.
If the ATO bit is set to one in the Control mode page (see 4.3.9) and checking of the LOGICAL BLOCK APPLICATION TAG field is enabled
(see table 192, table 193, table 194, and table 195 in 3.55), the LOGICAL BLOCK APPLICATION TAG MASK field contains a value that is
a bit mask for enabling the checking of the LOGICAL BLOCK APPLICATION TAG field in the protection information for each logical block
accessed by the command. A LOGICAL BLOCK APPLICATION TAG MASK bit set to one enables the checking of the corresponding bit of
the EXPECTED LOGICAL BLOCK APPLICATION TAG field with the corresponding bit of the LOGICAL BLOCK APPLICATION TAG field
in the protection information.
If the ATO bit is set to one in the Control mode page (see 4.3.9) and checking of the LOGICAL BLOCK APPLICATION TAG field is disabled
(see table 192, table 193, table 194, and table 195 in 3.55), or if the ATO bit is set to zero, the LOGICAL BLOCK APPLICATION TAG
MASK field and the EXPECTED LOGICAL BLOCK APPLICATION TAG field shall be ignored.
The LOGICAL BLOCK APPLICATION TAG MASK field and the EXPECTED LOGICAL BLOCK APPLICATION TAG field shall be ignored
if:
a)
b)

the ATO bit is set to zero; or
the ATO bit is set to one in the Control mode page (see 4.3.9) and checking of the LOGICAL BLOCK APPLICATION TAG field is
disabled (see table 192, table 193, table 194, and table 195 in 3.55).

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3.59

WRITE (6) command

This command has been declared obsolete by the T10 committee. However, it is included because it may be implemented on some
products.
The WRITE (6) command (see table 199) requests that the device server transfer the specified logical block(s) from the data-out buffer and
write them. Each logical block transferred includes user data but does not include protection information. Each logical block written
includes user data and, if the medium is formatted with protection information enabled, protection information.
Table 199
Bit
Byte

WRITE (6) command
7

6

5

4

3

2

1

0

OPERATION CODE (0Ah)

0
Reserved

1

(MSB)

2
LOGICAL BLOCK ADDRESS

3
4

TRANSFER LENGTH

5

CONTROL

(LSB)

The cache control bits are not provided for this command. Direct-access block devices with cache may have values for the cache control
bits that may affect the WRITE (6) command, however no default value is defined by this manual. If explicit control is required, the WRITE
(10) command should be used.
LOGICAL BLOCK ADDRESS field
See 2.2.3 for the definition of the LOGICAL BLOCK ADDRESS field.
TRANSFER LENGTH field
The TRANSFER LENGTH field specifies the number of contiguous logical blocks of data that shall be transferred from the data-out buffer
and written, starting with the logical block specified by the LOGICAL BLOCK ADDRESS field. A TRANSFER LENGTH field set to zero
specifies that 256 logical blocks shall be written. Any other value specifies the number of logical blocks that shall be written. If the logical
block address plus the transfer length exceeds the capacity of the medium, the device server shall terminate the command with CHECK
CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to LOGICAL BLOCK ADDRESS OUT
OF RANGE. The TRANSFER LENGTH field is constrained by the MAXIMUM TRANSFER LENGTH field in the Block Limits VPD page.
Note.

For the WRITE (10) command, WRITE (12) command, WRITE (16) command, and WRITE (32) command, a TRANSFER
LENGTH field set to zero specifies that no logical blocks are transferred.

If a WRITE (6) command is received after protection information is enabled the device server shall set the protection information as follows
as it writes each logical block to the medium:
a) the LOGICAL BLOCK GUARD field set to a properly generated CRC (see SPC-4 4.16);
b) the LOGICAL BLOCK REFERENCE TAG field set to:
A) the least significant four bytes of the LBA, if type 1 protection (see SPC-4) is enabled;
B)
a)

or
FFFFFFFFh, if type 2 protection or type 3 protection is enabled

and
the LOGICAL BLOCK APPLICATION TAG field set to:
A) FFFFh, if the ATO bit is set to one in the Control mode page (see 4.3.9); or
B) any value, if the ATO bit is set to zero in the Control mode page (see 4.3.9).

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3.60

WRITE (10) command

The WRITE (10) command (see table 200) requests that the device server transfer the specified logical block(s) from the data-out buffer
and write them. Each logical block transferred includes user data and may include protection information, based on the WRPROTECT field
and the medium format. Each logical block written includes user data and, if the medium is formatted with protection information enabled,
protection information.
Table 200
Bit
Byte

WRITE (10) command
7

6

0
WRPROTECT

3

2

1

0

DPO

FUA

Reserved

FUA_NV

Obsolete

(MSB)
LOGICAL BLOCK ADDRESS

...
5

(LSB)

6
7

4

OPERATION CODE (2Ah)

1
2

5

Reserved
(MSB)

8
9

GROUP NUMBER
TRANSFER LENGTH

(LSB)

CONTROL

See the READ (10) command (see 3.18) for the definition of the DPO bit. See 2.2.3 for the definition of the LOGICAL BLOCK ADDRESS
field. See 2.2.8 and SPC-4 for the definition of the GROUP NUMBER field.

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The device server shall check the protection information transferred from the data-out buffer based on the WRPROTECT field as
described in table 201.
Table 201

Code

000b

001b

[b]

WRPROTECT field (Sheet 1 of 2)
Logical unit
formatted with Field in protection
protection
information
information

No protection information received from application client to check

No

No protection information received from application client to check

Yes [e]

LOGICAL BLOCK
GUARD

Shall

LOGICAL BLOCK GUARD CHECK FAILED

LOGICAL BLOCK
APPLICATION TAG

May [c]

LOGICAL BLOCK APPLICATION TAG CHECK FAILED

LOGICAL BLOCK
REFERENCE TAG

Shall (except
for type 3)j

LOGICAL BLOCK REFERENCE TAG CHECK FAILED

No protection information available to check

Yes [e]

LOGICAL BLOCK
GUARD

Shall not

LOGICAL BLOCK
APPLICATION TAG

May [c]

LOGICAL BLOCK APPLICATION TAG CHECK FAILED

LOGICAL BLOCK
REFERENCE TAG

May [j]

LOGICAL BLOCK REFERENCE TAG CHECK FAILED

Yes [e]

LOGICAL BLOCK
GUARD

Shall not

No check performed

LOGICAL BLOCK
APPLICATION TAG

Shall not

No check performed

LOGICAL BLOCK
REFERENCE TAG

Shall not

No check performed

No protection information available to check

No [a]

100b [b]

Yes [e]

LOGICAL BLOCK
GUARD

Shall

LOGICAL BLOCK GUARD CHECK FAILED

LOGICAL BLOCK
APPLICATION TAG

Shall not

No check performed

LOGICAL BLOCK
REFERENCE TAG

Shall not

No check performed

No protection information available to check

No [a]

101b [b]

Yes [e]

No check performed

No protection information available to check

No [a]

011b [b]

If check fails [d] [i],
additional sense code

Yes [f] [g] [h]

No [a]

010b [b]

Device
server
check

LOGICAL BLOCK
GUARD

Shall

LOGICAL BLOCK GUARD CHECK FAILED

LOGICAL BLOCK
APPLICATION TAG

May [c]

LOGICAL BLOCK APPLICATION TAG CHECK FAILED

LOGICAL BLOCK
REFERENCE TAG

May [j]

LOGICAL BLOCK REFERENCE TAG CHECK FAILED

No [a]

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No protection information available to check

181

Table 201

Code

WRPROTECT field (Sheet 2 of 2)
Logical unit
formatted with Field in protection
protection
information
information

110b - 111b

Device
server
check

If check fails [d] [i],
additional sense code
Reserved

[a] A write operation to a logical unit that supports protection information and has not been formatted with protection information shall be terminated with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN CDB.
[b] If the logical unit does not support protection information the requested command should be terminated with CHECK
CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD
IN CDB.
[c] If the device server has knowledge of the contents of the LOGICAL BLOCK APPLICATION TAG field, and the ATO bit is
set to one in the Control mode page (see 4.3.9), then the device server:
a. may check each logical block application tag if the RWWP bit is set to zero in the Control mode page (see 4.3.9); and
b. shall check each logical block application tag if the RWWP bit is set to one in the Control mode page.
If the ATO bit in the Control mode page (see 4.3.9) is set to one, then this knowledge is acquired from:
a. the EXPECTED LOGICAL BLOCK APPLICATION TAG field and the LOGICAL BLOCK APPLICATION TAG MASK
field in the CDB, if a WRITE (32) command (see 5.36) is received by the device server;
b. the Application Tag mode page (see 6.4.3), if a command other than WRITE (32) is received by the device server and
the ATMPE bit in the Control mode page (see 4.3.9) is set to one
or
c. a method not defined by this standard, if a command other than WRITE (32) is received by the device server, and the
ATMPE bit is set to zero.
[d] If an error is reported, the sense key shall be set to ABORTED COMMAND.
[e] Device server shall preserve the contents of protection information (e.g., write to medium, store in non-volatile memory).
[f] The device server shall write a properly generated CRC into each LOGICAL BLOCK GUARD field.
[g] If the RWWP bit in the Control mode page (see 4.3.9) is set to one, then the device server shall terminate the command
with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to
INVALID FIELD IN CDB. If the RWWP bit is set to zero, and:
a. type 1 protection is enabled, then the device server shall write the least significant four bytes of each LBA into the
LOGICAL BLOCK REFERENCE TAG field of each of the written logical blocks; or
b. type 2 protection or type 3 protection is enabled, then the device server shall write a value of FFFF_FFFFh into the
LOGICAL BLOCK REFERENCE TAG field of each of the written logical blocks.
[h] If the ATO bit is set to one in the Control mode page (see 4.3.9), the device server shall write FFFFh into each LOGICAL
BLOCK APPLICATION TAG field. If the ATO bit is set to zero, the device server may write any value into each LOGICAL
BLOCK APPLICATION TAG field.
[i] If multiple errors occur, the selection of which error to report is not defined by this manual.
[j] If type 1 protection is enabled, the device server checks the logical block reference tag by comparing it to the lower 4
bytes of the LBA associated with the logical block. If type 2 protection or type 3 protection is enabled, the device server
checks the logical block reference tag if it has knowledge of the contents of the logical block reference tag field. If type 2
protection is enabled, then this knowledge may be acquired through the expected initial logical block reference tag field
in a WRITE (32) command (see 3.63). If type 3 protection is enabled, then the method for acquiring this knowledge is not
defined by this manual.

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The force unit access (FUA) and force unit access non-volatile cache (FUA_NV) bits are defined in table 202.
Table 202

Force unit access for write operations

FUA

FUA_NV

0

0

Description
The device server shall write the logical blocks to volatile cache, non-volatile cache, and/or the
medium.
If the NV_SUP bit is set to one in the Extended INQUIRY Data VPD page (see 4.4.7), the device
server shall write the logical blocks to non-volatile cache and/or the medium.

0

1
If the NV_SUP bit is set to zero in the Extended INQUIRY Data VPD page (see 4.4.7), the device
server shall write the logical blocks to volatile cache, non-volatile cache, and/or the medium.

1

0 or 1

The device server shall write the logical blocks to the medium, and shall not return GOOD status until
the logical blocks have actually been written on the medium without error.

If logical blocks are transferred directly to a cache, the device server may return GOOD status prior to writing the logical blocks to the
medium. Any error that occurs after the GOOD status is returned is a deferred error, and information regarding the error is not reported
until a subsequent command.
TRANSFER LENGTH field
The TRANSFER LENGTH field specifies the number of contiguous logical blocks of data that shall be transferred from the data-out buffer
and written, starting with the logical block specified by the LOGICAL BLOCK ADDRESS field. A TRANSFER LENGTH field set to zero
specifies that no logical blocks shall be written. This condition shall not be considered an error. Any other value specifies the number of
logical blocks that shall be written. If the logical block address plus the transfer length exceeds the capacity of the medium, the device
server shall terminate the command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional
sense code set to LOGICAL BLOCK ADDRESS OUT OF RANGE. The TRANSFER LENGTH field is constrained by the MAXIMUM
TRANSFER LENGTH field in the Block Limits VPD page.

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3.61

WRITE (12) command

The WRITE (12) command (see table 203) requests that the device server transfer the specified logical block(s) from the data-out buffer
and write them. Each logical block transferred includes user data and may include protection information, based on the WRPROTECT field
and the medium format. Each logical block written includes user data and, if the medium is formatted with protection information enabled,
protection information.
Table 203
Bit
Byte

WRITE (12) command
7

6

5

4

0

3

2

1

0

Reserved

FUA_NV

Obsolete

OPERATION CODE (AAh)

1

WRPROTECT

2

DPO

FUA

(MSB)
LOGICAL BLOCK ADDRESS

...
5

(LSB)

6

(MSB)
TRANSFER LENGTH

...
9

(LSB)

10

Restricted for
MMC-5

Reserved

GROUP NUMBER

11

CONTROL

See the WRITE (10) command (see 3.60) for the definitions of the fields in this command.
3.62

WRITE (16) command

The WRITE (16) command (see table 204) requests that the device server transfer the specified logical block(s) from the data-out buffer
and write them. Each logical block transferred includes user data and may include protection information, based on the WRPROTECT field
and the medium format. Each logical block written includes user data and, if the medium is formatted with protection information enabled,
protection information.
Table 204
Bit
Byte

WRITE (16) command
7

6

5

0

3

2

1

0

Reserved

FUA_NV

Reserved

OPERATION CODE (8Ah)

1
2

4

WRPROTECT
(MSB)

DPO

FUA

LOGICAL BLOCK ADDRESS

...
9
10

(LSB)
(MSB)

TRANSFER LENGTH

...
13
14

(LSB)
Restricted for
MMC-5

Reserved

15

GROUP NUMBER
CONTROL

See the WRITE (10) command (see 3.60) for the definitions of the fields in this command.

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3.63

WRITE (32) command

The WRITE (32) command (see table 205) requests that the device server transfer the specified logical block(s) from the data-out buffer
and write them. Each logical block transferred includes user data and may include protection information, based on the WRPROTECT field
and the medium format. Each logical block written includes user data and, if the medium is formatted with protection information enabled,
protection information.
The WRITE (32) command shall only be processed if type 2 protection is enabled (see SBC-3).
Table 205
Bit
Byte
0
1
2
...
5
6
7
8
9
10
11
12
...
19
20
...
23
24
25
26
27
28
...
31

WRITE (32) command
7

6

5

4

3

2

1

0

FUA_NV

(LSB)
Reserved

OPERATION CODE (7Fh)
CONTROL
Reserved
Reserved

GROUP NUMBER
ADDITIONAL CDB LENGTH (18h)

(MSB)

SERVICE ACTION (000Bh)
WRPROTECT

DPO

FUA
Reserved

Reserved

(MSB)
LOGICAL BLOCK ADDRESS
(LSB)
(MSB)
EXPECTED INITIAL LOGICAL BLOCK REFERENCE TAG
(LSB)
(MSB)

EXPECTED LOGICAL BLOCK APPLICATION TAG

(MSB)

LOGICAL BLOCK APPLICATION TAG MASK

(LSB)
(LSB)

(MSB)
TRANSFER LENGTH
(LSB)

See the WRITE (10) command (see 3.60) for the definitions of the GROUP NUMBER field, the WRPROTECT field, the DPO bit, the FUA
bit, the FUA_NV bit, the LOGICAL BLOCK ADDRESS field, and the TRANSFER LENGTH field.
When checking of the LOGICAL BLOCK REFERENCE TAG field is enabled (see table 201 in 3.60), the EXPECTED INITIAL LOGICAL
BLOCK REFERENCE TAG field contains the value of the LOGICAL BLOCK REFERENCE TAG field expected in the protection
information of the first logical block accessed by the command instead of a value based on the LBA.
If the ATO bit is set to one in the Control mode page (see 4.3.9) and checking of the LOGICAL BLOCK APPLICATION TAG field is enabled
(see table 201 in 3.60), the LOGICAL BLOCK APPLICATION TAG MASK field contains a value that is a bit mask for enabling the checking
of the LOGICAL BLOCK APPLICATION TAG field in the protection information for each logical block accessed by the command. A
LOGICAL BLOCK APPLICATION TAG MASK bit set to one enables the checking of the corresponding bit of the EXPECTED LOGICAL
BLOCK APPLICATION TAG field with the corresponding bit of the LOGICAL BLOCK APPLICATION TAG field in the protection
information.
The LOGICAL BLOCK APPLICATION TAG MASK field and the EXPECTED LOGICAL BLOCK APPLICATION TAG field shall be ignored
if:
a)
b)

the ATO bit is set to zero; or
the ATO bit is set to one in the Control mode page (see 4.3.9) and checking of the LOGICAL BLOCK APPLICATION TAG field is
disabled (see SBC-3).

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3.64

WRITE AND VERIFY (10) command

The WRITE AND VERIFY (10) command (see table 206) requests that the device server transfer the specified logical block(s) from the
data-out buffer, write them to the medium, and then verify that they are correctly written. Each logical block includes user data and may
include protection information, based on the WRPROTECT field and the medium format. The logical blocks are only transferred once from
the data-out buffer to the device server.
Table 206
Bit
Byte

WRITE AND VERIFY (10) command
7

6

0

5

4

3

2

1

0

BYTCHK

Obsolete

OPERATION CODE (2Eh)

1

WRPROTECT

2

DPO

Reserved

(MSB)
LOGICAL BLOCK ADDRESS

...
5

(LSB)

6

Reserved

7

(MSB)

8
9

GROUP NUMBER
TRANSFER LENGTH

(LSB)

CONTROL

See 2.2.3 for the definition of the LOGICAL BLOCK ADDRESS field. See 2.2.3 for the definition of the GROUP NUMBER field. See the
WRITE (10) command (see 3.60) for the definitions of the TRANSFER LENGTH field and the WRPROTECT field. See the READ (10)
command (see 3.18) for the definition of the DPO bit.
If the Verify Error Recovery mode page is also implemented, then the current settings in that mode page along with the AWRE bit in the
Read-Write Error Recovery mode page specify the verification error criteria. If these mode pages are not implemented, then the verification
criteria is vendor-specific.
BYTCHK bit
0

A byte check (BYTCHK) bit set to zero specifies that, after writing, the device server perform a medium verification with no data
comparison.

1

A BYTCHK bit set to one specifies that, after writing, the device server perform a byte-by-byte comparison of data written on the
medium with the data just written. If the comparison is unsuccessful for any reason, the device server shall terminate the command
with CHECK CONDITION status with the sense key set to MISCOMPARE and the additional sense code set to the appropriate
value for the condition.

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3.65

WRITE AND VERIFY (12) command

The WRITE AND VERIFY (12) command (see table 207) requests that the device server transfer the specified logical block(s) from the
data-out buffer, write them to the medium, and then verify that they are correctly written. Each logical block includes user data and may
include protection information, based on the WRPROTECT field and the medium format. The logical blocks are only transferred once from
the data-out buffer to the device server.
Table 207
Bit
Byte

WRITE AND VERIFY (12) command
7

6

5

0

4

3

2

1

0

BYTCHK

Obsolete

OPERATION CODE (AEh)

1

WRPROTECT

2

DPO

Reserved

(MSB)
LOGICAL BLOCK ADDRESS

...
5

(LSB)

6

(MSB)
TRANSFER LENGTH

...
9

(LSB)

10

Restricted for
MMC-5

Reserved

GROUP NUMBER

11

CONTROL

See the WRITE AND VERIFY (10) command (see 3.64) for the definitions of the fields in this command.
3.66

WRITE AND VERIFY (16) command

The WRITE AND VERIFY (16) command (see table 208) requests that the device server transfer the specified logical block(s) from the
data-out buffer, write them to the medium, and then verify that they are correctly written. Each logical block includes user data and may
include protection information, based on the WRPROTECT field and the medium format. The logical blocks are only transferred once from
the data-out buffer to the device server.
Table 208
Bit
Byte

WRITE AND VERIFY (16) command
7

6

5

0
WRPROTECT

1

0

DPO

Reserved

BYTCHK

Reserved

LOGICAL BLOCK ADDRESS
(LSB)
(MSB)
TRANSFER LENGTH

...
13
14

2

(MSB)

...
9
10

3

OPERATION CODE (8Eh)

1
2

4

(LSB)
Restricted for
MMC-5

Reserved

15

GROUP NUMBER
CONTROL

See the WRITE AND VERIFY (10) command (see 3.64) for the definitions of the fields in this command.

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3.67

WRITE AND VERIFY (32) command

The WRITE AND VERIFY (32) command (see table 209) requests that the device server transfer the specified logical block(s) from the
data-out buffer, write them to the medium, and then verify that they are correctly written. Each logical block includes user data and may
include protection information, based on the WRPROTECT field and the medium format. The logical blocks are only transferred once from
the data-out buffer to the device server.
Table 209
Bit
Byte

WRITE AND VERIFY (32) command
7

6

5

4

3

2

0

OPERATION CODE (7Fh)

1

CONTROL

1

0

2
Reserved

...
5
6

Reserved

GROUP NUMBER

7
8

ADDITIONAL CDB LENGTH (18h)
(MSB)

SERVICE ACTION (000Ch)

9
10

WRPROTECT

DPO

11
12

LOGICAL BLOCK ADDRESS
(LSB)
(MSB)
EXPECTED INITIAL LOGICAL BLOCK REFERENCE TAG
(LSB)
(MSB)

25
26

EXPECTED LOGICAL BLOCK APPLICATION TAG

(MSB)

27
28

Reserved

(MSB)

...
23
24

BYTCHK

Reserved

...
19
20

Reserved

(LSB)

LOGICAL BLOCK APPLICATION TAG MASK

(LSB)

(LSB)

(MSB)

...
31

TRANSFER LENGTH
(LSB)

See the WRITE AND VERIFY (10) command (see 3.64) for the definitions of the GROUP NUMBER field, the WRPROTECT field, the DPO
bit, the BYTCHK bit, the LOGICAL BLOCK ADDRESS field, and the TRANSFER LENGTH field.
When checking of the LOGICAL BLOCK REFERENCE TAG field is enabled (see table 201), the EXPECTED INITIAL LOGICAL BLOCK
REFERENCE TAG field contains the value of the LOGICAL BLOCK REFERENCE TAG field expected in the protection information of the
first logical block accessed by the command instead of a value based on the LBA.
If the ATO bit is set to one in the Control mode page (see 4.3.9) and checking of the LOGICAL BLOCK APPLICATION TAG field is enabled
(see table 201), the LOGICAL BLOCK APPLICATION TAG MASK field contains a value that is a bit mask for enabling the checking of the
LOGICAL BLOCK APPLICATION TAG field in the protection information for each logical block accessed by the command. A LOGICAL
BLOCK APPLICATION TAG MASK bit set to one enables the checking of the corresponding bit of the EXPECTED LOGICAL BLOCK
APPLICATION TAG field with the corresponding bit of the LOGICAL BLOCK APPLICATION TAG field in the protection information.
If the ATO bit is set to one in the Control mode page (see 4.3.9) and checking of the LOGICAL BLOCK APPLICATION TAG field is disabled
(see table 201), or if the ATO bit is set to zero, the LOGICAL BLOCK APPLICATION TAG MASK field and the EXPECTED LOGICAL
BLOCK APPLICATION TAG field shall be ignored.

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3.68

WRITE BUFFER command

3.68.1

WRITE BUFFER command introduction

The WRITE BUFFER command (see table 210) is used in conjunction with the READ BUFFER command for:
a) testing logical unit buffer memory;
b) testing the integrity of the service delivery subsystem;
c) downloading microcode; and
d) downloading application client error history (see SPC-4).
Table 210
Bit
Byte

WRITE BUFFER command
7

6

5

0
MODE SPECIFIC

2

2

1

0

MODE
BUFFER ID

(MSB)
BUFFER OFFSET

...
5
6

3

OPERATION CODE (3Bh)

1

3

4

(LSB)
(MSB)

...
8

PARAMETER LIST LENGTH

9

CONTROL

(LSB)

This command shall not alter any medium of the logical unit when the data mode or the combined header and data mode is specified.

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The function of this command and the meaning of fields within the CDB depend on the contents of the MODE field. The MODE field is
defined in table 211.
Table 211
Mode

WRITE BUFFER MODE field
Description

00h

Combined header and data [a]

01h

Not supported

02h

Data

04h

Download microcode and activate

05h

Download microcode, save and activate

06h

Download microcode with offsets [b] and activate

07h

Download microcode with offsets [b], save, and activate

08h - 09h
0Ah
0Bh - 0Ch

Reserved
Echo buffer
Reserved

0Dh

Download microcode with offsets, select activation events, save, and defer activate

0Eh

Download microcode with offsets, save, and defer active

0Fh

Activate deferred microcode

10h - 19h

Reserved

1Ah

Enable expander communications protocol and Echo buffer

1Bh

Disable expander communications protocol

1Ch

Download application log

1Dh - 1Fh

Reserved

[a] Mode 00h is not recommended.
[b] When downloading microcode with buffer offsets, the WRITE BUFFER command mode should be 06h or 07h.
3.68.2

Combined header and data mode (00h)

Note.

This mode is not recommended.

In this mode, data to be transferred is preceded by a four-byte header. The four-byte header consists of all reserved bytes. The BUFFER
ID and the BUFFER OFFSET fields shall be zero.
The MODE SPECIFIC field is reserved.
The PARAMETER LIST LENGTH field specifies the maximum number of bytes that shall be transferred from the Data-Out Buffer. This
number includes four bytes of header, so the data length to be stored in the device server’s buffer is parameter list length minus four. The
application client should attempt to ensure that the parameter list length is not greater than four plus the BUFFER CAPACITY field value
(see table 99) that is returned in the header of the READ BUFFER command (mode 0h). If the parameter list length exceeds the buffer
capacity, the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the
additional sense code set to INVALID FIELD IN CDB.

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3.68.3

Vendor specific mode (01h)

This mode is not supported by Seagate products. If used, the drive will return CHECK CONDITION and report an ILLEGAL REQUEST/
INVALID FIELD IN CDB error.
3.68.4

Data mode (02h)

In this mode, the Data-Out Buffer contains buffer data destined for the logical unit. The BUFFER ID field identifies a specific buffer within the
logical unit. Seagate assigns buffer ID codes to buffers within the logical unit. Buffer ID zero shall be supported. If more than one buffer is
supported, then additional buffer ID codes shall be assigned contiguously, beginning with one. If an unsupported buffer ID code is selected,
the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional
sense code set to INVALID FIELD IN CDB.
The MODE SPECIFIC field is reserved.
Data are written to the logical unit buffer starting at the location specified by the BUFFER OFFSET field. The application client should conform
to the offset boundary requirements returned in the READ BUFFER descriptor. If the device server is unable to accept the specified buffer
offset, the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the
additional sense code set to INVALID FIELD IN CDB.
The PARAMETER LIST LENGTH field specifies the maximum number of bytes that shall be transferred from the Data-Out Buffer to be
stored in the specified buffer beginning at the buffer offset. The application client should attempt to ensure that the parameter list length
plus the buffer offset does not exceed the capacity of the specified buffer. The capacity of the buffer is indicated by the BUFFER
CAPACITY field in the READ BUFFER descriptor (see table 99). If the BUFFER OFFSET and PARAMETER LIST LENGTH fields specify
a transfer in excess of the buffer capacity, the command shall be terminated with CHECK CONDITION status, with the sense key set to
ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN CDB.
3.68.5

Download microcode and activate mode (04h)

In this mode, microcode shall be transferred to the device server and activated (see SPC-4).
The MODE SPECIFIC field is reserved.
The BUFFER ID field, BUFFER OFFSET field, and PARAMETER LIST LENGTH field are vendor specific..
3.68.6

Download microcode, save, and activate mode (05h)

In this mode, microcode shall be transferred to the device server, saved to nonvolatile storage, and activated (see 5.4) based on the setting
of the ACTIVATE MICROCODE field in the Extended INQUIRY VPD page (see 4.4.7).
The MODE SPECIFIC field is reserved.
The BUFFER ID field, BUFFER OFFSET field, and PARAMETER LIST LENGTH field are vendor specific.
3.68.7

Download microcode with offsets and activate mode (06h)

In this mode, microcode shall be transferred to the device server using one or more WRITE BUFFER commands and activated (see SPC-4).
The MODE SPECIFIC field is reserved.
The BUFFER ID field specifies a buffer within the logical unit. The vendor assigns buffer ID codes to buffers within the logical unit. A buffer
ID value of zero shall be supported. If more than one buffer is supported, then additional buffer ID codes shall be assigned contiguously,
beginning with one. If an unsupported buffer ID code is specified, the command shall be terminated with CHECK CONDITION status, with
the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN CDB.
The BUFFER OFFSET field specifies the location in the buffer to which the microcode is written. The application client shall send
commands that conform to the offset boundary requirements returned in the READ BUFFER descriptor (see table 99). If the device server
is unable to process the specified buffer offset, the command shall be terminated with CHECK CONDITION status, with the sense key set
to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN CDB.
The PARAMETER LIST LENGTH field specifies the maximum number of bytes that shall be present in the Data-Out Buffer to be stored in
the specified buffer beginning at the buffer offset. The application client should ensure that the parameter list length plus the buffer offset
does not exceed the capacity of the specified buffer. If the BUFFER OFFSET and PARAMETER LIST LENGTH fields specify a transfer in
excess of the buffer capacity, then the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL
REQUEST, and the additional sense code set to INVALID FIELD IN CDB.

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3.68.8

Download microcode with offsets and save mode (07h)

In this mode, microcode shall be transferred to the device server using one or more WRITE BUFFER commands, saved to nonvolatile
storage, and activated (see 5.4) based on the setting of the ACTIVATE MICROCODE field in the Extended INQUIRY VPD page (see
4.4.7).
The BUFFER ID field, BUFFER OFFSET field, and PARAMETER LIST LENGTH field are defined in the download microcode with offsets
mode (see 3.68.7).
3.68.9

Write data to echo buffer mode (0Ah)

In this mode the device server transfers data from the application client and stores it in an echo buffer. An echo buffer is assigned in the
same manner by the device server as it would for a write operation. Data shall be sent aligned on four-byte boundaries. The BUFFER ID
and BUFFER OFFSET fields are ignored in this mode.
Note.

It is recommended that the logical unit assign echo buffers on a per I_T nexus basis to limit the number of exception conditions that may occur when I_T nexuses are present.

Upon successful completion of a WRITE BUFFER command the data shall be preserved in the echo buffer unless there is an intervening
command to any logical unit in which case the data may be changed.
The PARAMETER LIST LENGTH field specifies the maximum number of bytes that shall be transferred from the Data-Out Buffer to be
stored in the echo buffer. The application client should ensure that the parameter list length does not exceed the capacity of the echo
buffer. The capacity of the echo buffer is indicated by the BUFFER CAPACITY field in the READ BUFFER echo buffer descriptor (see
Table 101). If the PARAMETER LIST LENGTH field specifies a transfer in excess of the buffer capacity, the command shall be terminated
with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN
CDB.
3.68.10 Download microcode with offsets, select activation events, save, and defer activate mode (0Dh)
In this mode, microcode shall be transferred to the device server using one or more WRITE BUFFER commands, saved to nonvolatile
storage, and considered deferred (see SPC-4). The deferred microcode shall be activated and no longer considered deferred if a WRITE
BUFFER command with the activate deferred microcode mode (0Fh) is processed (see 3.68.12).
The MODE SPECIFIC field (see table 212) specifies additional events that shall be used to activate the deferred microcode.
Table 212
Bit

MODE SPECIFIC field
7

6

5

...

PO_ACT

HR_ACT

VSE_ACT

...

If the power on activate (PO_ACT) bit is set to one, then deferred microcode shall be activated and no longer considered deferred if a
power on occurs. If the PO_ACT bit is set to zero, then deferred microcode shall not be activated if a power on occurs.
If the hard reset activate (HR_ACT) bit is set to one, then deferred microcode shall be activated and no longer considered deferred if a
hard reset occurs. If the HR_ACT bit is set to zero, then deferred microcode shall not be activated if a hard reset occurs.
If the vendor specific event activate (VSE_ACT) bit is set to one, then deferred microcode shall be activated and no longer considered
deferred if a vendor specific event occurs. If the VSE_ACT bit is set to zero, then deferred microcode shall not be activated if a vendor
specific event occurs.
The supported activation events shall be reported in the POA_SUP bit, HRA_SUP bit, and VSA_SUP bit in the Extended INQUIRY VPD
page (see 4.4.7). If the MODE SPECIFIC field specifies an activation event that is not supported (e.g., if the PO_ACT bit is set to one and
the POA_SUP bit is set to zero), then the command shall be terminated with CHECK CONDITION status with the sense key set to
ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN CDB.
The BUFFER ID field, BUFFER OFFSET field, and PARAMETER LIST LENGTH field are defined in the download microcode with offsets
mode (see 3.68.7).

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3.68.11 Download microcode with offsets, save, and defer activate mode (0Eh)
In this mode, microcode shall be transferred to the device server using one or more WRITE BUFFER commands, saved to nonvolatile
storage, and considered deferred (see SPC-4).
The deferred microcode shall be activated and no longer considered deferred if any one of the following occurs:
a)
b)
c)
d)
e)

a power on;
a hard reset;
a START STOP UNIT command is processed (see 3.50);
a FORMAT UNIT command is processed (see 3.5); or
a WRITE BUFFER command with the activate deferred microcode mode (0Fh) is processed (see 3.68.12).

The MODE SPECIFIC field, BUFFER ID field, BUFFER OFFSET field, and PARAMETER LIST LENGTH field are defined in the download
microcode with offsets mode (see 3.68.7).
3.68.12 Activate deferred microcode mode (0Fh)
In this mode, deferred microcode that has been saved using the download microcode with offsets, select activation events, save, and defer
activate (see xxx) or download microcode with offsets, save, and defer activate mode (see 3.68.11), if any, shall be activated and no longer
considered deferred (see SPC-4).
The MODE SPECIFIC field is reserved.
The the BUFFER ID field, BUFFER OFFSET field, and PARAMETER LIST LENGTH field shall be ignored in this mode.
If there is no deferred microcode that has been saved using the download microcode with offsets, save, and defer activate mode, then the
WRITE BUFFER command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the
additional sense code set to COMMAND SEQUENCE ERROR.
3.68.13 Enable expander communications protocol and Echo buffer mode (1Ah)
Receipt of a WRITE BUFFER command with this mode (1Ah) causes a communicative expander (see SPI-5) to enter the expanded
communications protocol mode. Device servers in SCSI target devices that receive a WRITE BUFFER command with this mode shall
process it as if it were a WRITE BUFFER command with mode 0Ah (see 3.68.9).
The MODE SPECIFIC field is reserved.
3.68.14 Disable expander communications protocol mode (1Bh)
Receipt of a WRITE BUFFER command with this mode (1Bh) causes a communicative expander (see SPI-5) to exit the expanded
communications protocol mode and return to simple expander operation. Device servers in SCSI target devices that receive a WRITE
BUFFER command with this mode shall terminate the command with CHECK CONDITION status, with the sense key set to ILLEGAL
REQUEST, and the additional sense code set to INVALID FIELD IN CDB.
The MODE SPECIFIC field is reserved.

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3.68.15 Download application log mode (1Ch)
In this mode the device server transfers data from the application client and stores it in an application log. The format of the application log
data is as specified in table 213.
The MODE SPECIFIC field is reserved.
The BUFFER ID field and BUFFER OFFSET field are ignored in this mode.
Upon successful completion of a WRITE BUFFER command, the information contained in the application client error history parameter list
shall be appended to the application client error history in a format determined by the logical unit.
The PARAMETER LIST LENGTH field specifies the maximum number of bytes that shall be transferred from the Data-Out Buffer to be
stored in the application log. If the PARAMETER LIST LENGTH field specifies a transfer that exceeds the application log’s capacity, the
command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense
code set to INVALID FIELD IN CDB
The device server shall not return an error based on the contents of any of the field values defined in table 213 except:
a)
b)
c)

the CLR bit;
the ERROR LOCATION LENGTH field; and
the APPLICATION CLIENT ERROR HISTORY LENGTH field.

Table 213
Bit
Byte
0
...
7
8
9
10
11
12
...
17
18
19
20
21
22
23
24
25
26
...
m
m+1
...
n

Application log data WRITE BUFFER format
7

6

5

4

3

2

1

0

(MSB)
T10 VENDOR IDENTIFICATION
(LSB)
(MSB)

ERROR TYPE

(LSB)
CLR

Reserved
Reserved
(MSB)
TIME STAMP

(LSB)
Reserved
Reserved

CODE SET
ERROR LOCATION FORMAT

(MSB)
(MSB)

ERROR LOCATION LENGTH (m-25)
APPLICATION CLIENT ERROR HISTORY LENGTH (n-m)

(LSB)
(LSB)

(MSB)
ERROR LOCATION
(LSB)
APPLICATION CLIENT ERROR HISTORY

T10 VENDOR IDENTIFICATION field
The T10 VENDOR IDENTIFICATION field contains eight bytes of left-aligned ASCII data identifying the vendor of the product. The T10
vendor identification shall be one assigned by INCITS. A list of assigned T10 vendor identifications is in SPC-4 Annex E and on the T10
web site (http://www.T10.org).

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ERROR TYPE field
The ERROR TYPE field (see table 214) specifies the error detected by the application client.
Table 214

ERROR TYPE field

Code

Description

0000h

No error specified by the application client

0001h

An unknown error was detected by the application client

0002h

The application client detected corrupted data

0003h

The application client detected a permanent error

0004h

The application client detected a service response of SERVICE DELIVERY OR TARGET FAILURE
(SAM-5).

0005h - 7FFFh

Reserved

8000h - FFFFh

Vendor specific

CLR bit
If the CLR_SUP bit is set to one in the error history directory parameter data (see 3.68.15), a CLR bit set to one specifies that the device
server shall:
a) clear the portions of the error history that the device server allows to be cleared; and
b) ignore any application client error history specified in the parameter list.
If the CLR_SUP bit is set to one in the error history directory parameter data, a CLR bit set to zero specifies that the device server shall not
ignore the CLR bit.
If the CLR_SUP bit is set to one in the error history directory parameter data, a CLR bit set to zero specifies that the device server shall:
a)
b)

not clear the error history; and
process all application client error history specified in the parameter list.

If the CLR_SUP bit is set to zero in the error history directory parameter data, the device server shall ignore the CLR bit.
TIME STAMP field
The TIME STAMP field shall contain:
a) a time based on the timestamp reported by the REPORT TIMESTAMP command, if the device server supports a device clock
(see SPC-4)
b) The number of milliseconds that have elapsed since midnight, 1 January 1970 UT; or
c) Zero, if the application client is not able to determine the UT of the log entry.
CODE SET field
The CODE SET field specifies the code set used for the application log information (see table 215) and shall only apply to information contained in the VENDOR SPECIFIC field.
Note.

The CODE SET field is intended to be an aid to software that displays the application log information.

Table 215
Code

CODE SET field
Description

0h

Reserved

1h

The application log information is binary

2h

The application log information is ASCII printable characters (i.e., code values 20h through 7Eh)

3h

The application log information is ISO/IEC 10646-1 (UTF-8) codes

4h - Fh

Reserved

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ERROR LOCATION FORMAT field
The ERROR LOCATION FORMAT field specifies the format (see table 216) of the ERROR LOCATION field.
Table 216
Code

ERROR LOCATION FORMAT field
Description

00h

No error specified by the application client

01h

The ERROR LOCATION field specifies the logical block (e.g., LBA) associated with the error information
contained within the application log.

02h - 7Fh

Reserved

80h - FFh

Vendor specific

ERROR LOCATION LENGTH field
The ERROR LOCATION LENGTH field specifies the length of the ERROR LOCATION field. The ERROR LOCATION LENGTH field value
shall be a multiple of four. An error location length value of zero specifies there is no error location information.
APPLICATION CLIENT ERROR HISTORY LENGTH field
The APPLICATION CLIENT ERROR HISTORY LENGTH field specifies the length of the APPLICATION CLIENT ERROR HISTORY field.
The APPLICATION CLIENT ERROR HISTORY LENGTH field value shall be a multiple of four. A vendor specific length value of zero specifies there is no vendor specific information.
ERROR LOCATION field
The ERROR LOCATION field specifies the location at which the application client detected the error.
APPLICATION CLIENT ERROR HISTORY field
The APPLICATION CLIENT ERROR HISTORY field provides vendor specific information on the error.
3.69

WRITE LONG (10) command

The WRITE LONG (10) command (see table 217) requests that the device server mark a logical block or physical block as containing an
error, or transfer data for a single logical block from the data-out buffer and write it to the medium. The data written shall be the same length
and shall be in the same order as the data returned by the READ LONG (10) command (see 3.27). The device server shall write the logical
block to the medium, and shall not return GOOD status until the logical block has actually been written on the medium without error.
Table 217
Bit
Byte

WRITE LONG (10) command
7

6

5

0
1
2

4

3

2

0

OPERATION CODE (3Fh)
COR_DIS WR_UNCOR

PBLOCK

Reserved

Obsolete

(MSB)

...

LOGICAL BLOCK ADDRESS

5

(LSB)

6
7

1

Reserved
(MSB)

8
9

BYTE TRANSFER LENGTH

(LSB)

CONTROL

The OPERATION CODE field is defined in 2.2.1 shall be set to the value defined in table 217.
COR_DIS bit, WR_UNCOR bit and PBLOCK bit
The correction disabled (COR_DIS) bit, write uncorrectable error (WR_UNCOR) bit and physical block (PBLOCK) bit are define in table . If
there are more than one logical block per physical block (i.e., the LOGICAL BLOCKS PER PHYSICAL BLOCK EXPONENT field in the
READ CAPACITY (16) data (see 3.24) is set to a non-zero value), the device server shall support the WR_UNCOR bit and the PBLOCK
bit.

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Table 218

COR_DIS bit, WR_UNCOR bit and PBLOCK bit

COR_DIS WR_UNCOR

PBLOCK

0
0

More than
one logical
block per Description
physical
block []
yes or no

0

no

Terminate the WRITE LONG command with CHECK CONDITION status with the
sense key set to ILLEGAL REQUEST and the additional sense code set to
INVALID FIELD IN CDB.

yes

Write the entire physical block containing the specified logical block using the value
in the BYTE TRANSFER LENGTH field.

1

0

Write only the specified logical block using the value in the BYTE TRANSFER
LENGTH field.

yes or no

Mark only the specified logical block as containing a pseudo unrecovered error with
correction enabled (see SBC-3) in a manner that causes the device server to perform the maximum error recovery as defined by the Read-Write Error Recovery
mode page (see 4.3.16).
Ignore the BYTE TRANSFER LENGTH field, and transfer no data.

0

no

1

1
yes

Terminate the WRITE LONG command with CHECK CONDITION status with the
sense key set to ILLEGAL REQUEST and the additional sense code set to
INVALID FIELD IN CDB.
Mark the entire physical block containing the specified logical block as containing a
pseudo unrecovered error with correction enabled (i.e., mark all of the logical
blocks in the same physical block that contains the specified logical block as containing a pseudo unrecovered error with correction enabled) (see SBC-3).
Ignore the BYTE TRANSFER LENGTH field, and transfer no data.
Mark only the specified logical block as containing a pseudo unrecovered error with
correction disabled (see SBC-3)

0

yes or no
Write only the specified logical block using the value in the BYTE TRANSFER
LENGTH field.

1

no

0
1

yes

Terminate the WRITE LONG command with CHECK CONDITION status with the
sense key set to ILLEGAL REQUEST and the additional sense code set to
INVALID FIELD IN CDB.
Mark the entire physical block containing the specified logical block as containing a
pseudo unrecovered error with correction disabled (i.e., mark all of the logical
blocks in the same physical block that contains the specified logical block as containing a pseudo unrecovered error with correction disabled) (see SBC-3).
Write the entire physical block containing the specified logical block using the value
in the BYTE TRANSFER LENGTH field.

0

yes or no

Mark only the specified logical block as containing a pseudo unrecovered error with
correction disabled (see SBC-3).
Ignore the BYTE TRANSFER LENGTH field, and transfer no data.

1

no

1
1

yes

Terminate the WRITE LONG command with CHECK CONDITION status with the
sense key set to ILLEGAL REQUEST and the additional sense code set to
INVALID FIELD IN CDB.
Mark the entire physical block containing the specified logical block as containing a
pseudo unrecovered error with correction disabled (i.e., mark all of the logical
blocks in the same physical block that contains the specified logical block as containing a pseudo unrecovered error with correction disabled) (see SBC-3).
Ignore the BYTE TRANSFER LENGTH field, and transfer no data.

An entry of “yes” means that the LOGICAL BLOCKS PER PHYSICAL BLOCK EXPONENT field in the READ CAPACITY (16) data (see 3.24)
is set to a non-zero value. An entry of “no” means that the field is set to zero.
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Any pseudo unrecovered error with correction disabled shall remain in effect until the logical block is written by any means (e.g., another
WRITE LONG command with the COR_DIS bit set to zero and the WR_UNCOR bit set to zero that writes to the same logical block, any
WRITE command that specifies the writes to the same logical block, or a FORMAT UNIT command).
In the Extended INQUIRY Data VPD page (see 4.4.7), the setting of the CD_SUP bit indicates whether or not the logical unit supports the
CD_SUP bit being set to one, and the setting of the WU_SUP bit indicates whether or not the logical unit supports the WR_UNCOR bit
being set to one.
LOGICAL BLOCK ADDRESS field
The LOGICAL BLOCK ADDRESS field (see 2.2.3) specifies an LBA. If the specified LBA exceeds the capacity of the medium, then the
device server shall terminate the command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to LOGICAL BLOCK ADDRESS OUT OF RANGE
BYTE TRANSFER LENGTH field
If table defines that the value in the BYTE TRANSFER LENGTH field is used, then the BYTE TRANSFER LENGTH field specifies the
number of bytes of data that the device server shall transfer from the data-out buffer and write to the specified logical block or physical
block. If the BYTE TRANSFER LENGTH field is not set to zero and does not match the data length that the device server returns for a
READ LONG command, then the device server shall terminate the command with CHECK CONDITION status with the sense key set to
ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN CDB. In the sense data (see 2.4), the ILI and VALID bits shall
be set to one and the INFORMATION field shall be set to the difference (i.e., residue) of the requested length minus the actual length in
bytes. Negative values shall be indicated by two's complement notation. If the BYTE TRANSFER LENGTH field is set to zero, then no
bytes shall be written. This condition shall not be considered an error.
3.70

WRITE LONG (16) command

The WRITE LONG (16) command (see table 219) requests that the device server mark a logical block or physical block as containing an
error, or transfer data for a single logical block from the data-out buffer and write it to the medium. The data written shall be the same length
and shall be in the same order as the data returned by the READ LONG (16) command (see 3.28). The device server shall write the logical
block to the medium, and shall not return GOOD status until the logical block has been written on the medium without error. This command
is implemented as a service action of the SERVICE ACTION OUT operation code.
Table 219
Bit
Byte

WRITE LONG (16) command
7

6

5

0

4

3

2

1

0

OPERATION CODE (9Fh)

1

COR_DIS

2

(MSB)

WR_UNCOR

PBLOCK

SERVICE ACTION (11h)

LOGICAL BLOCK ADDRESS

...
9

(LSB)

10
Reserved

11
12

(MSB)

13

BYTE TRANSFER LENGTH

14

Reserved

15

CONTROL

(LSB)

The OPERATION CODE field (see 2.2.1) and SERVICE ACTION field are defined in (see 2.2.2) and shall be set to the values defined in
table 219.
See the WRITE LONG (10) command (see 3.69) for the definitions of the fields in this command.

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3.71

WRITE SAME (10) command

The WRITE SAME (10) command (see table 220) requests that the device server transfer a single logical block from the data-out buffer
and write the contents of that logical block to the specified range of logical block addresses. Each logical block includes user data and may
include protection information, based on the WRPROTECT field and the medium format.
Table 220
Bit
Byte
0
1
2
...
5
6
7
8
9

WRITE SAME (10) command
7

6

WRPROTECT

5

4

3

2

OPERATION CODE (41h)
ANCHOR
UNMAP
Obsolete

1

0

Obsolete

Obsolete

(MSB)
LOGICAL BLOCK ADDRESS
(LSB)
Reserved
(MSB)

GROUP NUMBER
NUMBER OF BLOCKS

(LSB)

CONTROL

WRPROTECT field
See the WRITE (10) command (see 3.60) for the definitions of the WRPROTECT field.
LOGICAL BLOCK ADDRESS field
See 2.2.3 for the definition of the LOGICAL BLOCK ADDRESS field.
GROUP NUMBER field
See clause 2.2.8 for the definition of the GROUP NUMBER field.
ANCHOR and UNMAP bits
If the logical unit supports logical block provisioning management (see SBC-3), then the ANCHOR bit, the UNMAP bit, and the ANC_SUP
bit in the Logical Block Provisioning VPD page (see 4.4.11) determine how the device server processes the command as described in
Table 221.
Table 221

ANCHOR bit, UNMAP bit, and ANC_SUP bit relationships
UNMAP bit [a]

ANCHOR bit

ANC_SUP bit [b]

Action

0b

n/a

Write [c]

1b

n/a

Error [d]

0b

n/a

Unmap [e]

0

Error [d]

1

Anchor [f]

0b

1b
1b

[a] The device server in a logical unit that supports logical block provisioning management (see SBC-3) may implement the UNMAP bit.
[b] See the Logical Block Provisioning VPD page (see 4.4.11).
[c] The device server shall perform the specified write operation on each LBA specified by the command.
[d] The device server shall terminate the command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and
the additional sense code set to INVALID FIELD IN CDB.
[e] The device server in a thin provisioned logical unit should deallocate each LBA specified by the command (see SBC-3) but may
anchor each LBA specified by the command (see SBC-3). The device server in a resource provisioned logical unit should anchor
each LBA specified by the command. If the device server does not deallocate or anchor the LBA, then the device server shall perform
the specified write operation (see SBC-3).
[f] The device server should anchor each LBA specified by the command (see SBC-3). If the device server does not anchor the LBA,
then the device server shall perform the specified write operation (see SBC-3).

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Table 222 describes the LBDATA bit and the PBDATA bit. (These bits were made obsolete in SBC-3)
Table 222
LBDATA

LBDATA bit and PBDATA bit
PBDATA

Description
The device server shall write the single block of user data received from the data-out buffer to each logical
block without modification.
If the medium is formatted with type 1 or type 2 protection information (see SBC-3):
a The device server shall place the value from each LOGICAL BLOCK REFERENCE TAG field received in
the single block of data from the data-out buffer into the corresponding LOGICAL BLOCK REFERENCE
TAG field of the first logical block written to the medium. The device sever shall place the value of the
previous LOGICAL BLOCK REFERENCE TAG field plus one into each of the subsequent LOGICAL
BLOCK REFERENCE TAG fields;
b If the ATO bit is set to one in the Control mode page (see 4.3.9), then the device server shall place each
logical block application tag received in the single block of data into the corresponding LOGICAL BLOCK
APPLICATION TAG field of each logical block. If the ATO bit is set to zero, then the device server may
write any value into the LOGICAL BLOCK APPLICATION TAG field(s) of each logical block; and
c The device server shall place the value from each LOGICAL BLOCK GUARD field received in the single
block of data from the data-out buffer into the corresponding LOGICAL BLOCK GUARD field of each
logical block
If the medium is formatted with type 3 protection information (see SBC-3):
a If the ATO bit is set to one in the Control mode page (see 4.3.9), then the device server shall place each
logical block application tag received in the single block of data into the corresponding LOGICAL BLOCK
REFERENCE TAG field of each logical block. If the ATO bit is set to zero, then the device server may
write any value into the LOGICAL BLOCK REFERENCE TAG field(s) of each logical block; and
b The device server shall place the value from each LOGICAL BLOCK GUARD field received in the single
block of data from the data-out buffer into the corresponding LOGICAL BLOCK GUARD field of each
logical block.

0

0

0

1 [a]

1 [a]

0

The device server shall replace the first four bytes of the block received from the data-out buffer with the least
significant four bytes of the LBA of the block being written, ending with the least significant byte (e.g., if the
LBA is 77665544_33221100h, 33221100h is written with 33h written first and 00h written last).

1

1

The device server shall terminate the command with CHECK CONDITION status with the sense key set to
ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN CDB.

The device server shall replace the first eight bytes of the block received from the data-out buffer to each
physical sector with the physical address of the sector being written using the physical sector format (see
3.5.5.7).

[a] If the medium is formatted with protection information then the protection information shall be written to a default value of
FFFFFFFF_FFFFFFFFh in each of the written logical blocks.
NUMBER OF BLOCKS field
The NUMBER OF BLOCKS field specifies the number of contiguous logical blocks to be written, starting with the logical block specified by
the LOGICAL BLOCK ADDRESS field. A NUMBER OF BLOCKS field set to zero specifies that the device server write all the logical blocks
starting with the one specified in the LOGICAL BLOCK ADDRESS field to the last logical block on the medium. If the logical block address
plus the number of blocks exceeds the capacity of the medium, the device server shall terminate the command with CHECK CONDITION
status with the sense key set to ILLEGAL REQUEST and the additional sense code set to LOGICAL BLOCK ADDRESS OUT OF RANGE.

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3.72

WRITE SAME (16) command

The WRITE SAME (16) command (see table 223) requests that the device server transfer a single logical block from the data-out buffer
and write the contents of that logical block to the specified range of logical block addresses. Each logical block includes user data and may
include protection information, based on the WRPROTECT field and the medium format. The WRITE SAME (16) command with the
UNMAP bit supported is one of the possible commands that shall be implemented by device servers supporting thin provisioning (see
SBC-3).
Table 223
Bit
Byte

WRITE SAME (16) command
7

6

4

3

2

1

0

(Obsolete)

(Obsolete)

Reserved

OPERATION CODE (93h)

0
WRPROTECT

1
2

5

ANCHOR

UNMAP

(MSB)
LOGICAL BLOCK ADDRESS

...

(LSB)

9
10

(MSB)
NUMBER OF BLOCKS

...

(LSB)

13
14

Reserved

15

GROUP NUMBER
CONTROL

See the WRITE SAME (10) command (see 3.71) for the definitions of the fields in this command.

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3.73

WRITE SAME (32) command

The WRITE SAME (32) command (see table 224) requests that the device server transfer a single logical block from the data-out buffer
and write the contents of that logical block. Each logical block includes user data and may include protection information, based on the
WRPROTECT field and the medium format. See the WRITE SAME (10) command (see 3.71) for the definition of the function of this
command.
Table 224
Bit
Byte
0
1
2
...
5
6
7
8
9
10
11
12
...
19
20
...
23
24
25
26
27
28
...
31

WRITE SAME (32) command
7

6

5

4

3

2

1

0

(Obsolete)

(LSB)
Reserved

OPERATION CODE (7Fh)
CONTROL
Reserved
Reserved

GROUP NUMBER
ADDITIONAL CDB LENGTH (18h)

(MSB)

SERVICE ACTION (000Dh)
WRPROTECT

ANCHOR
UNMAP
Reserved

(Obsolete)

(MSB)
LOGICAL BLOCK ADDRESS
(LSB)
(MSB)
EXPECTED INITIAL LOGICAL BLOCK REFERENCE TAG
(LSB)
(MSB)

EXPECTED LOGICAL BLOCK APPLICATION TAG

(MSB)

LOGICAL BLOCK APPLICATION TAG MASK

(LSB)
(LSB)

(MSB)
NUMBER OF BLOCKS
(LSB)

The OPERATION CODE field, the ADDITIONAL CDB LENGTH field, and the SERVICE ACTION field are defined in SPC-4 and shall be
set to the values shown in table 224 for the WRITE SAME (32) command.
See the WRITE SAME (10) command (see 3.71) for the definitions of the GROUP NUMBER field, the WRPROTECT field, the ANCHOR
bit, the UNMAP bit, the PBDATA bit, the LBDATA bit, the LOGICAL BLOCK ADDRESS field, and the NUMBER OF BLOCKS field.
When checking of the LOGICAL BLOCK REFERENCE TAG field is enabled (see 3.71), the EXPECTED INITIAL LOGICAL BLOCK
REFERENCE TAG field contains the value of the LOGICAL BLOCK REFERENCE TAG field expected in the protection information of the
first logical block accessed by the command instead of a value based on the LBA (see SBC-3).
If the ATO bit is set to one in the Control mode page (see 4.3.9) and checking of the LOGICAL BLOCK APPLICATION TAG field is enabled
(see 3.71), then the LOGICAL BLOCK APPLICATION TAG MASK field contains a value that is a bit mask for enabling the checking of the
LOGICAL BLOCK APPLICATION TAG field in every instance of protection information for each logical block accessed by the command. A
LOGICAL BLOCK APPLICATION TAG MASK bit set to one enables the checking of the corresponding bit of the EXPECTED LOGICAL
BLOCK APPLICATION TAG field with the corresponding bit of the LOGICAL BLOCK APPLICATION TAG field in every instance of
protection information.
If the ATO bit is set to one in the Control mode page (see 4.3.9) and checking of the LOGICAL BLOCK APPLICATION TAG field is disabled
(see 3.71), or if the ATO bit is set to zero, then the LOGICAL BLOCK APPLICATION TAG MASK field and the EXPECTED LOGICAL
BLOCK APPLICATION TAG field shall be ignored.

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4.0

Parameters for all device types

This clause provides information on parameters for Diagnostic (Receive Diagnostic), Log (Sense), Mode (Sense), Protocol specific, and
Vital product data (Inquiry) pages
4.1

Diagnostic parameters

4.1.1

Diagnostic page format and page codes for all device types

This subclause describes the diagnostic page structure and the diagnostic pages that are applicable to all SCSI devices. Diagnostic pages
specific to each device type are described in the command standard that applies to that device type.
A SEND DIAGNOSTIC command with a PF bit set to one specifies that the SEND DIAGNOSTIC parameter list consists of a single
diagnostic page and that the data returned by the subsequent RECEIVE DIAGNOSTIC RESULTS command that has the PCV bit set to
zero shall use the diagnostic page format defined in table 225. A RECEIVE DIAGNOSTIC RESULTS command with a PCV bit set to one
specifies that the device server return a diagnostic page using the format defined in table 225.
Table 225
Bit
Byte

Diagnostic page format
7

6

5

3

2

1

0

PAGE CODE

0

PAGE CODE SPECIFIC

1
2

4

(MSB)

3

PAGE LENGTH (N-3)

(LSB)

4
...

DIAGNOSTIC PARAMETERS

n
Each diagnostic page defines a function or operation that the device server shall perform as a result of a SEND DIAGNOSTIC command or
the information being returned as a result of a RECEIVE DIAGNOSTIC RESULTS command with the PCV bit equal to one. The diagnostic
parameters contain data that is formatted according to the page code specified.

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PAGE CODE field
The PAGE CODE field identifies the diagnostic page (see table 226).
Table 226

Diagnostic page codes

Page Code

Diagnostic Page Name
Supported Diagnostic Pages

4.1.2

Defined by SES-3 for:
a Enclosure services devices (i.e., SCSI devices with the PERIPHERAL
DEVICE TYPE field set to 0Dh in standard INQUIRY data); and
b SCSI devices with the ENCSERV bit set to one in standard INQUIRY data
(see 3.6.2).

4.1.5

00h

01h - 2Fh

Note.
30h - 3Eh
3Fh
40h
41h
42h

Reference

These pages are described in SES-3 these pages are passed
along to any attached enclosure services device.

Reserved
See specific SCSI transport protocol for definition

SPC-4

Translate Address Input diagnostic page

4.1.3

Translate Address Output diagnostic page

4.1.4

See specific device type for definition
Rebuild Assist Input diagnostic page

4.1.6

Rebuild Assist Output diagnostic page

4.1.7

43h - 7Fh

See specific device type for definition

80h - FFh

Vendor specific

PAGE LENGTH field
The PAGE LENGTH field contains the length in bytes of the diagnostic parameters that follow this field. If the application client sends a
SEND DIAGNOSTIC command with a parameter list containing a PAGE LENGTH field that results in the truncation of any parameter, then
the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional
sense code set to INVALID FIELD IN PARAMETER LIST.
The diagnostic parameters are defined for each diagnostic page code. The diagnostic parameters within a diagnostic page may be defined
differently in a SEND DIAGNOSTIC command than in a RECEIVE DIAGNOSTIC RESULTS command.

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4.1.2

Supported diagnostic pages (00h)

The Supported Diagnostic Pages diagnostic page (see table 227) returns the list of diagnostic pages implemented by the device server.
This diagnostic page shall be implemented if the device server implements the diagnostic page format option of the SEND DIAGNOSTIC
and RECEIVE DIAGNOSTIC RESULTS commands.
Table 227
Bit
Byte

Supported diagnostic pages
7

6

5

4

3

0

PAGE CODE (00h)

1

Reserved

2

(MSB)

3

2

PAGE LENGTH (N-3)

1

0

(LSB)

4
..

SUPPORTED PAGE LIST

n
The definition of this diagnostic page for the SEND DIAGNOSTIC command includes only the first four bytes. If the PAGE LENGTH field is
not zero, the device server shall terminate the SEND DIAGNOSTIC command with CHECK CONDITION status, with the sense key set to
ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN PARAMETER LIST. This diagnostic page instructs the device
server to make available the list of all supported diagnostic pages to be returned by a subsequent RECEIVE DIAGNOSTIC RESULTS
command.
The definition of this diagnostic page for the RECEIVE DIAGNOSTIC RESULTS command includes the list of diagnostic pages supported
by the device server.
PAGE LENGTH field
The PAGE LENGTH field specifies the length in bytes of the following supported page list.
SUPPORTED PAGE LIST field
The SUPPORTED PAGE LIST field shall contain a list of all diagnostic page codes, one per byte, implemented by the device server in
ascending order beginning with page code 00h.

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4.1.3

Translate Address input page (40h)

Table 228 defines the Translate Address Input diagnostic page retrieved with the RECEIVE DIAGNOSTIC RESULTS command after the
Translate Address Output diagnostic page (see 4.1.4) has been sent with the SEND DIAGNOSTIC command. If a Translate Address
Output diagnostic page has not yet been processed, the results of a RECEIVE DIAGNOSTIC RESULTS command requesting this
diagnostic page are vendor specific.
Table 228
Bit
Byte

Translate Address page—input diagnostic page (40h)
7

6

5

4

3

0

PAGE CODE (40h)

1

Reserved

2

2

1

0

(MSB)
PAGE LENGTH (n-3)

3

(LSB)

4

Reserved

5

RAREA

ALTSEC

SUPPLIED FORMAT

ALTTK

Reserved

TRANSLATED FORMAT

TRANSLATED ADDRESS (if available)
(MSB)

6

TRANSLATED ADDRESS 1

...

(LSB)

13
…
n-7

(MSB)
TRANSLATED ADDRESS x (if required)

...

(LSB)

n
PAGE CODE field
The PAGE CODE field is defined in 4.1.1 and shall be set to the value defined in Table 228 and Table 41.
PAGE LENGTH field
The PAGE LENGTH field is defined in (see 4.1.1).
SUPPLIED FORMAT field

The SUPPLIED FORMAT field contains the value from the SEND DIAGNOSTIC command supplied format field (see Table 228).
RAREA (Reserved Area) bit
1

A Reserved Area (RAREA) bit of one indicates that all or part of the translated address falls within a reserved area of the medium
(e.g., speed tolerance gap, alternate logical block, vendor reserved area, etc.). If the entire translated address falls within a
reserved area the target may not return a translated address.

0

An RAREA bit of zero indicates that no part of the translated address falls within a reserved area of the medium.

TRANSLATED FORMAT field
The TRANSLATED FORMAT field contains the format description of the translated address(es) (see Table 41)..

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Table 229

Address Field for Short Logical Block Address Format

Bit
Byte

7

0

(MSB)

6

5

4

3

2

1

0

LOGICAL BLOCK ADDRESS

...
3

(LSB)

4

0

0

0

0

0

0

0

0

5

0

0

0

0

0

0

0

0

6

0

0

0

0

0

0

0

0

7

0

0

0

0

0

0

0

0

3

2

1

0

Table 230

Address Field for Physical Sector Address Format

Bit
Byte

7

0

(MSB)

6

5

4

CYLINDER NUMBER

1
2

(LSB)

3

HEAD NUMBER

4
...

SECTOR NUMBER

7
ALTSEC (Alternate Sector) bit
1

An Alternate Sector (ALTSEC) bit of one indicates that the translated address is physically located in an alternate sector of the
medium. If the drive cannot determine if all or part of the translated address is located in an alternate sector it shall set this bit to
zero.

0

An ALTSEC bit of zero indicates that no part of the translated address is located in an alternate sector of the medium or that the
drive is unable to determine this information.

ALTTRK (Alternate Track) bit
1

An Alternate Track (ALTTRK) bit of one indicates that part or all of the translated address is located on an alternate track of the
medium or the drive cannot determine if all or part of the translated address is located on an alternate track.

0

An ALTTRK bit of zero indicates that no part of the translated address is located on an alternate track of the medium.

TRANSLATED ADDRESS field
The TRANSLATED ADDRESS field contains the address the target translated from the address supplied by the initiator in the SEND
DIAGNOSTIC command. This field shall be in the format specified in the translate format field. The supported formats are shown in Tables
229 and 230.

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4.1.4

Translate Address Output diagnostic page (40h)

The Translate Address diagnostic pages allow the application client to translate an address in one of the formats supported by the
FORMAT UNIT command (see 3.5.5.1) (i.e., a short block format address, a long block format address, a physical sector format address,
or a bytes from index format address) into any one of the other formats. The address to be translated is sent to the device server with the
SEND DIAGNOSTIC command and the results are returned to the application client by the RECEIVE DIAGNOSTIC RESULTS command.
Table 231 defines the format of the Translate Address Output diagnostic page sent with the SEND DIAGNOSTIC command. The
translated address is returned in the Translate Address Input diagnostic page (see 4.1.3).
Table 231

Translate Address Output diagnostic page

Bit
Byte

7

6

5

4

3

0

PAGE CODE (40h)

1

Reserved

2
3
4

(MSB)

5
6
.....
13

2

1

PAGE LENGTH (000Ah)

0

(LSB)

Reserved

SUPPLIED FORMAT

Reserved

TRANSLATE FORMAT

(MSB)
ADDRESS TO TRANSLATE
(LSB)

PAGE CODE field
The PAGE CODE field is defined in 4.1.1 and shall be set to the value defined in table 231.
PAGE LENGTH field
The PAGE LENGTH field is defined in (see 4.1.1).
SUPPLIED FORMAT field
The SUPPLIED FORMAT field specifies the format of the ADDRESS TO TRANSLATE field. Valid values for this field are defined in the
DEFECT LIST FORMAT of the FORMAT UNIT command (see 3.5). If the device server does not support the requested format it shall terminate the SEND DIAGNOSTIC command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN PARAMETER LIST.
TRANSLATE FORMAT field
The TRANSLATE FORMAT field specifies the format the device server shall use for the result of the address translation. Valid values for
this field are defined in the DEFECT LIST FORMAT field of the FORMAT UNIT command. If the device server does not support the specified format it shall terminate the SEND DIAGNOSTIC command with CHECK CONDITION status with the sense key set to ILLEGAL
REQUEST and the additional sense code set to INVALID FIELD IN PARAMETER LIST.
ADDRESS TO TRANSLATE field
The ADDRESS TO TRANSLATE field contains a single address descriptor which the application client is requesting the device server to
translate. The format of this field depends on the value in the SUPPLIED FORMAT field. The formats are described in (see 3.5.5.1). If the
short block format address descriptor is specified, the first four bytes of the ADDRESS TO TRANSLATE field shall contain the short block
format address descriptor and the last four bytes shall contain 0000_0000h.

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4.1.5

SCSI Enclosure Services pages (01h - 2Fh)

When the drive supports the SCSI Enclosure Service (SES) pages, it does not process the contents of the pages. The drive attempts to
transfer the page contents to the enclosure using the Enclosure Services Interface (ESI) as directed by the command. Errors detected in
the transfer are returned to the initiator in response to the command. See SCSI-3 Enclosure Services -2 (SES-2) for descriptions of the
data presented in the SES pages. Reference the drive product manual to determine if the SES pages are supported.
Table 232

SCSI Enclosure Services page

Bit
Byte

7

6

5

4

3

0

PAGE CODE (01h - 2Fh)

1

Page Specific

2

2

1

0

(MSB)
PAGE LENGTH (n - 3)

3

(LSB)

4
...

Page Specific

n
PAGE CODE
The PAGE CODE (01h - 2Fh) defined in SCSI Enclosure Services - 2 (SES-2) standard.
Page Specific
The Page Specific field is defined in the SCSI-3 Enclosure Services - 2 (SES-2) standard.
PAGE LENGTH
The PAGE LENGTH field is defined in (see 4.1.1).

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4.1.6

Rebuild Assist Input diagnostic page

Application client sends a RECEIVE DIAGNOSTIC RESULTS command to retrieve a Rebuild Assist Input diagnostic page (see table 233),
which provides information about whether the rebuild assist mode (see SBC-3) is enabled or not and a device server’s rebuild assist mode
capabilities.
Table 233

Rebuild Assist Input diagnostic page

Bit
Byte

7

6

5

3

2

1

0

PAGE CODE (42h)

0

Reserved

1
2

4

(MSB)

PAGE LENGTH (4 + (2 x n))

3

ENABLED

(LSB)

Reserved

4
5

Reserved

6
PHYSICAL ELEMENT LENGTH (n)

7
8
...

DISABLED PHYSICAL ELEMENT MASK

7+n
8+n
...

DISABLED PHYSICAL ELEMENT

7 + (2 x n)
PAGE CODE field
The PAGE CODE field is defined in 4.1.1 and shall be set to the value defined in table 233.
PAGE LENGTH field
The PAGE LENGTH field is defined in (see 4.1.1).
ENABLED bit
1

An ENABLED bit set to one indicates that the rebuild assist mode is enabled.

0

An ENABLED bit set to zero indicates that the rebuild assist mode is disabled.

PHYSICAL ELEMENT LENGTH field
The PHYSICAL ELEMENT LENGTH field indicates the length in bytes of the DISABLED PHYSICAL ELEMENT MASK field and the length
in bytes of the DISABLED PHYSICAL ELEMENT field.
DISABLED PHYSICAL ELEMENT MASK field
The bits in the DISABLED PHYSICAL ELEMENT MASK field indicate the bits in the DISABLED PHYSICAL ELEMENT field that are supported. Each bit set to one in the DISABLED PHYSICAL ELEMENT MASK field indicates that the corresponding bit in the DISABLED
PHYSICAL ELEMENT field is supported and may be set to one in a Rebuild Assist Output diagnostic page sent with a SEND DIAGNOSTIC command.
DISABLED PHYSICAL ELEMENT field
The bits in the DISABLED PHYSICAL ELEMENT field indicate the physical elements that are disabled in this logical unit. Each bit set to
one indicates that a physical element is disabled, and the device server shall report predicted read errors and predicted write errors for the
associated group of LBAs.

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4.1.7

Rebuild Assist Output diagnostic page

An An application client sends a SEND DIAGNOSTIC command to send a Rebuild Assist Output diagnostic page (see table 234) that:
a. enables or disables rebuild assist mode (see SBC-3); and/or
b. puts the logical unit in a simulated failure mode by disabling physical elements in conjunction with rebuild assist mode (see SBC-3).
Table 234

Rebuild Assist Output diagnostic page

Bit
Byte

7

6

5

4

3

2

1

0

PAGE CODE (42h)

0

Reserved

1
(MSB)

2

PAGE LENGTH (4 + (2 x n))

3

ENABLED

(LSB)

Reserved

4
5

Reserved

6
PHYSICAL ELEMENT LENGTH (n)

7
8

DISABLED PHYSICAL ELEMENT MASK

...
7+n
8+n

DISABLE PHYSICAL ELEMENT

...
7 + (2 x n)
PAGE CODE field

The PAGE CODE field is defined in 4.1.1 and shall be set to the value defined in table 234.
PAGE LENGTH field
The PAGE LENGTH field is defined in (see 4.1.1).
ENABLED bit
1

The ENABLED bit set to one indicates that, after all fields in this diagnostic page have been validated:
a. a self-test of the physical elements in the logical unit may be performed; and
b. rebuild assist mode is enabled.

0

The ENABLE bit set to zero specifies that:
a. rebuild assist mode shall be disabled;
b. the other fields in this page shall be ignored; and
c. all physical elements shall be enabled (i.e., shall not simulate a predicted error response).

PHYSICAL ELEMENT LENGTH field
The PHYSICAL ELEMENT LENGTH field shall be set to the same value that is returned in the PHYSICAL ELEMENT LENGTH field in the
Rebuild Assist Input diagnostic page.
If the PHYSICAL ELEMENT LENGTH field is not set to the same value that is returned in the PHYSICAL ELEMENT LENGTH field in the
Rebuild Assist Input diagnostic page, then the device server shall terminate the command with CHECK CONDITION status with the sense
key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN PARAMETER LIST.
DISABLED PHYSICAL ELEMENT MASK field
The device server shall ignore the DISABLED PHYSICAL ELEMENT MASK field.

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DISABLED PHYSICAL ELEMENT field
Each bit in the DISABLE PHYSICAL ELEMENT field specifies a physical element that shall be disabled. A bit set to one in the DISABLE
PHYSICAL ELEMENT field specifies that the device server shall respond to read commands and write commands specifying LBAs associated with that physical element as if the associated LBAs have predicted errors. A bit set to zero in the DISABLE PHYSICAL ELEMENT
field specifies that the device servers shall not respond to read commands and write commands specifying LBAs associated with that
physical element as if the associated LBAs do not have predicted errors. If the ENABLE bit is set to one, and the DISABLE PHYSICAL
ELEMENT field specifies:
a. any bits set to one that are not supported by the logical unit;
b. all bits that are supported by the logical unit are set to one; or
c. setting to zero any bits that are set to one,
then the device server shall terminate the command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and
the additional sense code set to INVALID FIELD IN PARAMETER LIST.
4.2

Log parameters

4.2.1

Summary of log page codes

The page code assignments for the log pages are listed in table 235.
Table 235

Log page codes

Page Code

Log Page Name

Reference

0Fh

Application Client

4.2.3

15h

Background Scan Results

4.2.4

19h

Cache Memory Statistics

4.2.5

3Eh

Factory Log

4.2.7

2Fh

Informational Exceptions

4.2.6

06h

Non-Medium Error

4.2.9

1Ah

Power Condition Transitions

4.2.10

18h

Protocol Specific Port

4.2.11

03h

Read Error Counter

4.2.6

10h

Self-Test Results

4.2.12

11h

Solid State Media

4.2.13

0Eh

Start-Stop Cycle Counter

4.2.14

00h

Supported Log Pages

4.2.15

00h

Supported Log Pages and Subpages

4.2.16

0Dh

Temperature

4.2.17

05h

Verify Error Counter

4.2.6

02h

Write Error Counter

4.2.6

08h - 0Ah

Reserved (may be used by specific device types)

0Ch

Reserved (may be used by specific device types)

11h - 14h

Reserved (may be used by specific device types)

16h - 17h

Reserved (may be used by specific device types)

19h - 2Eh

Reserved (may be used by specific device types)

3Fh
30h - 3Eh

Reserved
Vendor specific

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4.2.2

Log page structure and page codes for all device types

This subclause describes the log page structure and the log pages that are applicable to all SCSI devices. Log pages specific to each
device type are described in the command standard that applies to that device type. The LOG SELECT command (see 3.7) supports the
ability to send zero or more log pages. The LOG SENSE command (see 3.8) returns a single log page specified in the PAGE CODE field
of the CDB.
4.2.2.1

Log page format

Each log page begins with a four-byte page header followed by zero or more variable-length log parameters defined for that log page. The
log page format is defined in table 236.
Table 236

Log page format

Bit
Byte

7

6

0

DS

SPF

5

1

4

3

2

1

0

PAGE CODE
SUBPAGE CODE

2

(MSB)

3

PAGE LENGTH (n-3)

(LSB)

Log parameter(s)
4
Log parameter (First)
(Length x)

...
x+3
...

...

n-y+1
Log parameter (Last)
(Length y)

...
n
DS (DISABLE SAVE) bit
0

For the LOG SENSE command (see 3.8), if the DS bit is set to zero, the log parameters are saved when the SP bit is set to one.

1

For the LOG SENSE command, if the DS bit is set to one, the log parameters are not saved. For the LOG SELECT command (see
3.7), the disable save (DS) bit operates in conjunction with the parameter code reset (PCR) bit, the save parameters (SP) bit, the
page control (PC) field, and the PARAMETER LIST LENGTH field in the CDB.

SPF (SUBPAGE FORMAT) bit
0
1

If the SPF bit is set to zero, the SUBPAGE CODE field shall contain 00h.
If the SPF bit is set to one, the SUBPAGE CODE field shall contain a value between 01h and FFh.

PAGE CODE field
The value in the PAGE CODE field is the number of the log page being transferred.
SUBPAGE CODE field
The value in the SUBPAGE CODE field is the number of the subpage page being transferred.
If an application client specifies values in the PAGE CODE field and SUBPAGE CODE field for a log page that is reserved or not
implemented by the logical unit, then the device server shall terminate the LOG SELECT command with CHECK CONDITION status, with
the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN PARAMETER LIST.

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If the PARAMETER LIST LENGTH field in a LOG SELECT CDB contains zero, the meanings for the PCR bit, SP bit, and PC field are
defined in table 61.
If the PARAMETER LIST LENGTH field in a LOG SELECT CDB contains a non-zero value (i.e., when parameter data is being sent with
the LOG SELECT command), table 237 defines the meaning for the combinations of values for:
a. the PCR bit, the SP bit, and the PC field in the LOG SELECT CDB; and
b. the DS bit in the LOG SELECT parameter data.
Table 237

LOG SELECT PCR bit, SP bit, and DS bit meanings when parameter list length is not zero

PCR
bit

SP
bit

DS
bit

0b

0b

xb

The device server shall set the specified values to the values in the parameter list and shall not save any values
to non-volatile media.

0b

1b

0b

The device server shall set the specified values to the values in the parameter list and shall process the optional
saving of log parameter values as follows:
a) If default data counter values are specified (see table 67), no values shall be saved;
b) If values other than default data counter values are specified and the device server implements saving of
the specified values, then the device server shall save the specified values in the parameter list to nonvolatile media; or
c) If values other than default values are specified and the device server does not implements saving of one or
more of the specified values, then the device server shall terminate the command with CHECK
CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to
INVALID FIELD IN PARAMETER LIST.

0b

1b

1b

The device server shall set the specified values to the values in the parameter list and shall not save any values
in the specified log page to non-volatile media.

1b

xb

xb

The device server terminate the command with CHECK CONDITION status, with the sense key set to ILLEGAL
REQUEST, and the additional sense code set to INVALID FIELD IN CDB.

Description

The specified parameters are determined by the format and linking field contents (see table 240) in the LOG SELECT parameter data and
by the PC field contents (see table 67) in the LOG SELECT CDB.
PAGE LENGTH field
The value in the PAGE LENGTH field is the length in bytes of the following log parameters. If the application client sends a LOG SELECT
command with a log page length that results in the truncation of any parameter, the device server shall terminate the command with
CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN
PARAMETER LIST.

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4.2.2.2
4.2.2.2.1

Log parameter format
Introduction

Most log pages contain one or more special data structures called log parameters (see table 238). Log parameters may be data counters
of a particular event(s), the conditions under which certain operations were performed, or list parameters that contain a character string
description of a particular event.
Table 238
Bit
Byte
0
1
2

Log parameter
7

6

5

(MSB)

DU

4

3

PARAMETER CODE

Obsolete

TSD

3
4
...
n

Parameter control byte (see 4.2.2.2.2)
ETC
TMC
PARAMETER LENGTH (N-3)

2

1

0

(LSB)
FORMAT and LINKING

PARAMETER VALUE

Each log parameter begins with a four-byte parameter header followed by one or more bytes of PARAMETER VALUE data.
PARAMETER CODE field
The PARAMETER CODE field identifies the log parameter being transferred for that log page. The device server shall return the log
parameters in a log page in ascending order based on the value in their PARAMETER CODE field.
If an application client specifies a value in the PARAMETER CODE field in the LOG SELECT command parameter data that is reserved or
not implemented by the logical unit, then the device server shall terminate the command with CHECK CONDITION status, with the sense
key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN PARAMETER LIST.
DU bit, TSD bit, ETC bit, TMC field, and FORMAT AND LINKING
The DU bit, TSD bit, ETC bit, TMC field, and FORMAT AND LINKING field are collectively referred to as the parameter control byte. The
bits and fields in the parameter control byte are described in 4.2.2.2.2.
PARAMETER LENGTH field
The PARAMETER LENGH field specifies the length in bytes of the PARAMETER VALUE field that follows. If the application client specifies
a parameter lengh that results in the truncation of the PARAMETER VALUE field, the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN PARAMETER LIST.
If an application client sends a log parameter that is not supported by the logical unit, the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN PARAMETER LIST.
PARAMETER VALUE field
If the application client sends a log parameter value of the PARAMETER VALUE field that is outside the range supported by the logical
unit, and rounding is implemented for that parameter, the device server may either:
a) round to an acceptable value and terminate the command as described in 2.3; or
b) terminate the command with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional
sense code set to INVALID FIELD IN PARAMETER LIST.
If the parameter data for one LOG SELECT command contains more than one log page and the log pages are not in ascending order by
page code value then subpage code value, then the device server shall terminate the command with CHECK CONDITION status, with the
sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN PARAMETER LIST.
If the parameter data for one LOG SELECT command contains more than one log parameter in any one log page and the log parameters
are not in ascending order by parameter code value, then the device server shall terminate the command with CHECK CONDITION status,
with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN PARAMETER LIST.
Application clients should send LOG SENSE commands prior to sending LOG SELECT commands to determine supported log pages and
page lengths.
The SCSI target device may provide independent sets of log parameters for each logical unit or for each combination of logical units and
I_T nexuses. If the SCSI target device does not support independent sets of log parameters and any log parameters are changed that
affect other I_T nexuses, then the device server shall establish a unit attention condition (see SAM-5) for the initiator port associated with
every I_T nexus except the I_T nexus on which the LOG SELECT command was received, with the additional sense code set to LOG
PARAMETERS CHANGED.

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4.2.2.2.2

Parameter control byte

4.2.2.2.2.1

Introduction

DU bit, TSD bit, ETC bit, TMC field, and FORMAT AND LINKING field are collectively referred to as the parameter control byte. These
fields are described in this subclause.
DU (Disable Update) bit
For cumulative log parameter values, indicated by the PC field (see table 67) of the LOG SELECT command and LOG SENSE command,
the disable update (DU) bit is defined as follows:
0

DU set to zero indicates that the device server shall update the log parameter value to reflect all events that should be noted by that
parameter; or

1

DU set to one indicates that the device server shall not update the log parameter value except in response to a LOG SELECT command that specifies a new value for the parameter.

Note.

When updating cumulative log parameter values, a device server may use volatile memory to hold these values until a LOG
SELECT or LOG SENSE command is received with an SP bit set to one or a vendor specific event occurs. As a result the
updated cumulative log parameter values may be lost if a power cycle occurs.

If the PC field (see table 67) indicates that threshold values or default values are being processed, the device server shall:
a. set the DU bit to zero, if a LOG SENSE command is being processed; and
b. ignore the DU bit, if a LOG SELECT command is being processed.
Regardless of the value in the PC field, the device server shall process ASCII format list log parameters (see 4.2.2.2.2.4) and binary format
list log parameters (see 4.2.2.2.2.5) by:
a. setting the DU bit to zero, if a LOG SENSE command is being processed; and
b. ignoring the DU bit, if a LOG SELECT command is being processed.
TSD (Target Save Disable) bit
0

A target save disable (TSD) bit set to zero indicates that the logical unit implicitly saves the log parameter at vendor specific intervals. This implicit saving operation shall be done frequently enough to insure that the cumulative parameter values retain statistical
significance
(i.e., across power cycles).

1

A TSD bit set to one indicates that either the logical unit does not implicitly save the log parameter or implicit saving of the log
parameter has been disabled individually by an application client setting the TSD bit to one. An application client may disable the
implicit saving for all log parameters without changing any TSD bits using the GLTSD bit in the Control mode page. (see 4.3.9)

ETC (Enable Threshold Comparison) bit
1

An enable threshold comparison (ETC) bit set to one indicates that a comparison to the threshold value is performed whenever the
cumulative value is updated.

0

An ETC bit set to zero indicates that a comparison is not performed. The value of the ETC bit is the same for cumulative and threshold parameters.

TMC (Threshold Met Criteria) field
The threshold met criteria (TMC) field (see table 239) defines the basis for comparison of the cumulative and threshold values. The TMC
field is valid only if the ETC bit is set to one. The value of the TMC field is the same for cumulative and threshold parameters.
Table 239
Code

Threshold met criteria (TMC) field
Basis for comparison

00b Every update of the cumulative value
01b Cumulative value

equal to

threshold value

10b Cumulative value

not equal to

threshold value

11b Cumulative value

greater than

threshold value

If the ETC bit is set to one and the result of the comparison is true, a unit attention condition shall be established for the initiator port associated with every I_T nexus, with the additional sense code set to THRESHOLD CONDITION MET.

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FORMAT AND LINKING field
The FORMAT AND LINKING field (see table 240) indicates the type of log parameter.
Table 240

FORMAT AND LINKING field

Code

Log parameter type

Reference

00b

Bounded data counter

4.2.2.2.2.2

01b

ASCII format list

4.2.2.2.2.4

10b

Bounded data counter or
unbounded data counter

4.2.2.2.2.2 or
4.2.2.2.2.3

11b

Binary format list

4.2.2.2.2.5

4.2.2.2.2.2

Parameter control byte values for bounded data counter parameters

The device server shall return LOG SENSE parameter control byte values and process LOG SELECT parameter control byte values as
shown in table 241 for any log parameter that is defined to be a bounded data counter log parameter.
Table 241
Field or bit

Parameter control byte values for bounded data counter parameters
Value for
Value for
LOG SENSE LOG SELECT

Description

DU

0 or 1

0 or 1

When the DU bit is set to zero, the device server shall update the log parameter value to
reflect all events that should be noted by that parameter. When the DU bit is set to one, the
device server shall not update the log parameter value except in response to a LOG
SELECT command that specifies a new value for the parameter.

TSD

0 or 1

0 or 1

When the TSD bit is set to zero, the device server shall save the log parameter to its medium
at vendor specific intervals. When the TSD bit is set to one, implicit saving of the log parameter is disabled by an application client.

ETC

0 or 1

0 or 1

When the ETC bit is set to one, a comparison to the threshold value is performed whenever
the cumulative value is updated. When the ETC bit is set to zero, a comparison is not performed.

TMC

any

any

The TMC field (see table 239) defines the basis for comparison of the cumulative and threshold values. The TMC field is valid only if the ETC bit is set to one.

FORMAT AND
00b or 10b
LINKING

00b or 10b

The log parameter is a data counter (see table 240) and the handling of a parameter that
reaches its maximum value is described in this subclause.

If a LOG SELECT command contains a bounded data counter log parameter in which the parameter control byte values differ from those
shown in table 241, then the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL
REQUEST, and the additional sense code set to INVALID FIELD IN PARAMETER LIST.
Each bounded data counter log parameter contains one saturating counter that is:
a. associated with one or more events; and
b. incremented whenever one of these events occurs.
If the counter in a bounded data counter log parameter has associated with it a vendor specific maximum value, then upon reaching this
maximum value, the data counter shall not be incremented (i.e., its value does not wrap).

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If the counter in a bounded data counter log parameter reaches its maximum value (i.e., saturates), the device server shall:
a. set the DU bit to one;
b. handle other bounded data counter log parameters in the log page based on the contents of the
FORMAT AND LINKING field in each other log parameter as follows:
A) if the FORMAT AND LINKING field is set to 00b, then that other log parameter shall stop incrementing until reinitialized by a
LOG SELECT command; or
B) if the FORMAT AND LINKING field is set to 10b, then that other log parameter shall not stop incrementing, but may be
reinitialized by a LOG SELECT command.
and
c. not alter the handling of other log parameters in the log page that are:
A) unbounded data counter log parameters (see 4.2.2.2.2.3);
B) ASCII format list log parameters (see 4.2.2.2.2.4); and
C) binary format list log parameters (see 4.2.2.2.2.5).
The processing of a command shall not be altered because the counter in a bounded data counter log parameter reaches its maximum
value (i.e., saturates). If the RLEC bit is set to one in the Control mode page (see 4.3.9) and the processing of a command encounters no
exception conditions other than the counter in a bounded data counter log parameter reaching its maximum value, then the command shall
be terminated with CHECK CONDITION status, with the sense key set to RECOVERED ERROR, and the additional sense code set to
LOG COUNTER AT MAXIMUM.
4.2.2.2.2.3

Parameter control byte values for unbounded data counter parameters

The device server shall return LOG SENSE parameter control byte values and process LOG SELECT parameter control byte values as
shown in table 242 for any log parameter that is defined to be an unbounded data counter log parameter.
Table 242
Field
or bit

Parameter control byte values for unbounded data counter parameters
Value for
LOG SENSE

Value for
LOG SELECT

Description

DU

0 or 1

0 or 1

If the DU bit is set to zero, the device server shall update the log parameter value or values
to reflect all events that should be noted by that parameter. If the DU bit is set to one, the
device server shall not update the log parameter value or values except in response to a
LOG SELECT command that specifies a new value for the parameter.

TSD

0 or 1

0 or 1

If the TSD bit is set to zero, the device server shall save the log parameter to its medium at
vendor specific intervals. If the TSD bit is set to one, implicit saving of the log parameter is
disabled by an application client.

ETC

0

0

Threshold comparisons are not performed for unbounded data counter parameters.

TMC

00b

ignored

Threshold comparisons are not performed for unbounded data counter parameters.

FORMAT
AND
LINKING

10b

10b

The log parameter is a data counter for which saturation of another log parameter does not
affect the incrementing of this log parameter (see table 239).

If a LOG SELECT command contains an unbounded data counter log parameter in which the parameter control byte values differ from
those shown in table 242, then the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL
REQUEST, and the additional sense code set to INVALID FIELD IN PARAMETER LIST.
Each unbounded data counter log parameter contains one or more saturating counters or wrapping counters. The description of each
counter field in the log parameter defines when the device server modifies the contents of the counter that is transferred in that field.
Changes in an unbounded data counter (e.g., a counter reaching saturation or another maximum value) shall not affect the handling of
other log parameters in the log page. The processing of a command and the status returned by that command shall not be altered because
a counter in an unbounded data counter log parameter saturates or reaches its maximum value.
The device server shall not change the value in the DU bit in an unbounded data counter log parameter unless requested to do so by a
LOG SELECT command.

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4.2.2.2.2.4

Parameter control byte values for ASCII format list log parameters

The device server shall return LOG SENSE parameter control byte values and process LOG SELECT parameter control byte values as
shown in table 243 for any log parameter that is defined to be an ASCII format (see SPC-4) list log parameter.
Table 243

Parameter control byte values for ASCII format list log parameters

Field
or bit

Value for
LOG SENSE

Value for
LOG SELECT

DU

0

ignored

TSD

0 or 1

0 or 1

ETC

0

0

Threshold comparisons are not performed for list parameters.

TMC

00b

ignored

Threshold comparisons are not performed for list parameters.

FORMAT
AND
LINKING

01b

01b

Description
The DU bit is not defined for list parameters.
If the TSD bit is set to zero, the device server shall save the log parameter to its medium at
vendor specific intervals. If the TSD bit is set to one, implicit saving of the log parameter is
disabled by an application client.

The log parameter is an ASCII format list parameter (see table 239).

If a LOG SELECT command contains an ASCII format list log parameter in which the parameter control byte values differ from those
shown in table 243, then the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL
REQUEST, and the additional sense code set to INVALID FIELD IN PARAMETER LIST.
4.2.2.2.2.5

Parameter control byte values for binary format list log parameters

The device server shall return LOG SENSE parameter control byte values and process LOG SELECT parameter control byte values as
shown in table 244 for any log parameter that is defined to be a binary format list log parameter.
Table 244

Parameter control byte values for binary format list log parameters

Field
or bit

Value for
LOG SENSE

Value for
LOG SELECT

DU

0

ignored

TSD

0 or 1

0 or 1

ETC

0

0

Threshold comparisons are not performed for list parameters.

TMC

00b

ignored

Threshold comparisons are not performed for list parameters.

FORMAT
AND
LINKING

01b

01b

Description
The DU bit is not defined for list parameters.
If the TSD bit is set to zero, the device server shall save the log parameter to its medium at
vendor specific intervals. If the TSD bit is set to one, implicit saving of the log parameter is
disabled by an application client.

The log parameter is a binary format list parameter (see table 239).

If a LOG SELECT command contains a binary format list log parameter in which the parameter control byte values differ from those shown
in table 244, then the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and
the additional sense code set to INVALID FIELD IN PARAMETER LIST.

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4.2.2.3

Resetting and setting log parameters

In a LOG SELECT command, an application client may specify that:
a. all the parameters in a log page or pages are to be reset (i.e., the PCR bit set to one);
or
b. individual parameters in log page are to be changed to specified new values
(i.e., the PCR bit set to zero and the PARAMETER LIST LENGTH field not set to zero).
The device server handling of these requests depends on the log parameter that is being reset or changed, and is defined in the table that
defines the log parameter using the keywords defined in table 245.
Table 245

Keywords for resetting or changing log parameters

Device server handling when
PCR bit is set to one
PCR bit is set to zero [b]
Always
Reset the log parameter
Change the log parameter
If any changes are requested in the parameter value field of
Reset Only
Reset the log parameter
the log parameter, then
a) terminate the command with CHECK CONDITION
status, with the sense key set to ILLEGAL REQUEST,
and the additional sense code set to INVALID FIELD IN
Never
Do not reset the log parameter.
PARAMETER LIST; and
b) do not make any requested changes in any field in any
log parameter in any log page
[a] If the PCR bit is set to one and the PARAMETER LIST LENGTH field is not set to zero. then the LOG
SELECT command shall be terminated (see table 237).
Keyword

[a]

[b] If the PCR bit is set to zero and the PARAMETER LIST LENGTH field is set to zero. then no log parameters
are changed (see 3.7.1).
4.2.3

Application Client log page (0Fh)

The parameter codes for the Application Client log page are listed in Table 246.
Table 246

Application Client log page parameter codes

Parameter code
0000h to 003Fh
0040h to 0FFFh
all others

Description

Resettable or
Changeable (PCR) [a]

General Usage Application Client

Always

Support
requirements
Mandatory
Optional

Reserved

[a] The keywords in this column -- Always, Reset Only, and Never -- are defined in 4.2.2.3.

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The Application Client log page (see table 247) provides a place for application clients to store information. The page code for the
application client page is 0Fh.
Table 247

Application client log page

Bit
Byte

7

6

0

DS

SPF (0b)

5

3

2

1

0

PAGE CODE (0Fh)

1
2

4

SUBPAGE CODE (00h) (see 4.2.2.1)
(MSB)

PAGE LENGTH (n-3)

3

(LSB)

Application client log parameters
4
First application client log parameter

...

...
...
Last application client log parameter

n

The PAGE CODE and PAGE LENGTH fields are described in 4.2.2.
Parameter codes 0000h through 0FFFh are for general usage application client data. The intended use for this information is to aid in
describing the system configuration and system problems, but the specific definition of the data is application client specific. The general
usage application client data parameters all have the format shown in table 248.
Table 248

General usage application client parameter data

Bit
Byte

7

0

(MSB)

6

5

3

2

1

PARAMETER CODE

1
2

4

0

(LSB)

PARAMETER CONTROL BYTE – binary format list log parameter (see 4.2.2.2.2.5)
DU

Obsolete

TSD

3

ETC

TMC

FORMAT AND LINKING

PARAMETER LENGTH (FCh)

4
...

GENERAL USAGE PARAMETER BYTES

255
PARAMETER CODE field
For general usage application client data, the value in the PARAMETER CODE field shall be between 0000h and 0FFFh. The first supported general usage application client parameter code shall be 0000h and additional supported parameters shall be sequentially numbered. If any general usage parameter codes are implemented, the device shall support at least 64 general usage parameter descriptors
and they shall be parameter codes 0000h through 003Fh.
PARAMETER LENGTH value
For the general usage application client parameter, the PARAMETER LENGTH value for each parameter shall be FCh.
GENERAL USAGE PARAMETER BYTES
The values stored in the GENERAL USAGE PARAMETER BYTES represent data sent to the device server in a previous LOG SELECT
command. If a previous LOG SELECT command has not occurred, the data is vendor specific.

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4.2.4

Background Scan log page (15h)

The Background Scan log page (see table 250) returns the background scanning status parameter and zero or more Medium Scan
parameters when background scanning is supported. The Background Scanning Status parameter provides information about background
pre-scan and background medium scan operations. Each Background Medium Scan Medium error log entry corresponds to a logical block
where an error was detected. If the Background Scan log page is filled up, a new Background Medium Scan parameter overwrites the
oldest entry. When a LOG SELECT command with PCR bit set to one is processed all Background Medium Scan parameters are deleted,
however, the values in the Background Scan Status parameter shall not be affected.
Table 249 defines the parameter codes for the Background Scan Results log page.
Table 249

Background Scan log page parameter codes

Parameter code
0000h
0001h - 0800h
8000h - AFFFh
All others

Resettable or
Changeable [a]

Description

Reference

Support
Required

Background Scan Status parameter

Never

Mandatory

Background Scan parameter

Reset
Only

Optional [b]

Vendor specific

n/a

Optional

Reserved

[a] The keywords in this column -- Always, Reset Only, and Never -- are defined in 4.2.2.3.
[b] If the Background Scan log page is supported, then at least one Background Scan Results log parameter shall be supported.
The Background Scan log page has the format shown in table 250.
Table 250

Background Scan log page

Bit
Byte

7

6

0

DS (1)

SPF (0)

5

3

2

1

0

PAGE CODE (15h)
SUBPAGE CODE(00h) (see 4.2.2.1)

1
2

4

(MSB)

PAGE LENGTH (n-3)

3

(LSB)

Background Scan Status log parameter
4
Background Scan Status Parameter (see table 251)

...
19

Background Scan parameter list
20

(MSB)
Background Scan parameter (first) (see table 253)

...

(LSB)

43
...
n-23
...

(MSB)
Background Scan parameter (last) (see table 253)

n

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The background Scan Status parameter (see table 251) contains status information about the background pre-scan and background
medium scan features.
Table 251

Background Scan Status parameter format

Bit
Byte

7

0

(MSB)

6

5

2

1

DU

Obsolete

TSD

(LSB)

ETC

TMC

FORMAT AND LINKING

PARAMETER LENGTH (0Ch)
(MSB)
ACCUMULATED POWER ON MINUTES

...

(LSB)

7
8

Reserved

9

BACKGROUND SCAN STATUS

10

(MSB)

11
12

0

Parameter control byte – binary format list log parameter (see 4.2.2.2.2.5)

3
4

3

PARAMETER CODE (0000h)

1
2

4

(MSB)

13
14
15

NUMBER OF BACKGROUND SCANS PERFORMED

BACKGROUND MEDIUM SCAN PROGRESS

(LSB)

(LSB)

NUMBER OF BACKGROUND MEDIUM SCANS PERFORMED

PARAMETER CODE field
For general usage application client data, the value in the PARAMETER CODE field shall be between 0000h and 0FFFh. The first
supported general usage application client parameter code shall be 0000h and additional supported parameters shall be sequentially numbered. If any general usage parameter codes are implemented, the device shall support at least 64 general usage
parameter descriptors and they shall be parameter codes 0000h through 003Fh.
PARAMETER LENGTH field
The PARAMETER LENGTH field indicates that number of bytes remaining in the log parameter.
ACCUMULATED POWER ON MINUTES field
The ACCUMULATED POWER ON MINUTES field indicates the number of minutes the device server has been powered on since
manufacturing.

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Table 252 defines the BACKGROUND SCAN STATUS field.
Table 252
Code

Background Scan Status field
Description

00h

No background scans active

01h

Background medium scan is active

02h

Background pre-scan is active

03h

Background medium scan halted due to fatal error

04h

Background medium scan halted due to a vendor-specific pattern of errors

05h

Background medium scan halted due to medium formatted without P-list

06h

Background medium scan halted - vendor-specific cause

07h

Background medium scan halted due to temperature out of allowed range

08h

Background medium scan halted, waiting for Background Medium Interval timer expiration.

09h - FFh

Reserved

NUMBER OF SCANS PERFORMED field
The NUMBER OF SCANS PERFORMED field indicates the number of background scans (i.e., the total number of background pre-scan
operations plus the number of background medium scan operations) that have been performed since the SCSI target device was shipped
by the manufacturer.
BACKGROUND MEDIUM SCAN PROGRESS field
The BACKGROUND MEDIUM SCAN PROGRESS field indicates the percent complete of a background scan operation in progress. The
returned value is a numerator that has 65 536 (i.e., 1_0000h) as its denominator. If there is no background scan operation in progress (i.e.,
no background scan operation has been initiated since power on or the most recent background scan operation has completed), then the
device server shall set the BACKGROUND MEDIUM SCAN PROGRESS field to 0000h.
NUMBER OF BACKGROUND MEDIUM SCAN PERFORMED field
The NUMBER OF BACKGROUND MEDIUM SCAN PERFORMED field indicates the number of background medium scan operations that
have been performed since the SCSI target device was shipped by the manufacturer. If the NUMBER OF BACKGROUND MEDIUM SCAN
PERFORMED field contains 0000h, then the number of background medium scan operations is not reported.
A Background Medium Scan parameter (see table 253) describes a defect location on the medium that was encountered by background
scanning.
Table 253

Background Medium Scan parameter format

Bit
Byte

7

0

(MSB)

6

5

2

1

0

(LSB)

Parameter control byte – binary format list log parameter (see 4.2.2.2.2.5)
DU

Obsolete

TSD

ETC

TMC

FORMAT AND LINKING

PARAMETER LENGTH (14h)

3
4

3

PARAMETER CODE (0001h - 0800h)

1
2

4

(MSB)
ACCUMULATED POWER ON MINUTES

...

(LSB)

7
REASSIGN STATUS

8

SENSE KEY

9

ADDITIONAL SENSE CODE

10

ADDITIONAL SENSE CODE QUALIFIER

11
Vendor-specific

...
15
16

(MSB)

...
23

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(LSB)

224

PARAMETER LENGTH field
The PARAMETER LENGTH field indicates the number of bytes remaining in the log parameter.
ACCUMULATED POWER ON MINUTES field
The ACCUMULATED POWER ON MINUTES field indicates the number of minutes the device server has been powered on since manufacturing at the time the background scan error occurred.
Table 254 defines the REASSIGN STATUS field.
Table 254

REASSIGN STATUS field
LOWIR bit [a]

Code

Reason

0

1

Original
Error [b]

1h

Yes

Yes

Recovered or
unrecovered

2h

Yes

No

Recovered

The device server performed automatic read reassignment for the LBA (i.e., performed a
reassign operation for the LBA and a write operation with recovered logical block data). [d]

4h

Yes

Yes

Recovered

The device server’s attempt to perform automatic read reassignment failed. The logical
block may or may not now have an uncorrectable error. [c]

5h

Yes

No

Recovered

The error was corrected by the device server rewriting the logical block without performing
a reassign operation.

Recovered or
unrecovered

Either:
a) an application client caused automatic write reassignment for the LBA with a command performing a write operation; or
b) the LBPRZ bit is set to one in the Logical Block Provisioning VPD page (see 4.2.13),
and an application client caused an unmap operation for the LBA. [c]

6h

Yes

Yes

Additional conditions
The LBA has not yet been reassigned. [c]

7h

Yes

Yes

Recovered or
unrecovered

Either:
a) an application client caused a reassign operation for the LBA with a REASSIGN
BLOCKS command; or
b) the LBPRZ bit is set to zero in the Logical Block Provisioning VPD page (see 4.2.13),
and an application client caused an unmap operation for the LBA.. [c]

8h

Yes

Yes

Recovered or
unrecovered

An application client’s request for a reassign operation for the LBA with a REASSIGN
BLOCKS command failed. The logical block referenced by the LBA may or may not still
have an uncorrectable error.

All
others

Reserved.

[a] Based on the LOWIR bit in the Background Control mode page (see 4.3.7), “No” specifies that a Background Scan Results log
parameter shall not be generated for the error and “Yes” specifies that a Background Scan Results log parameter shall be generated
for the error.
[b] Type of error detected while reading the logical block referenced by the LBA specified by the LOGICAL BLOCK ADDRESS field
during a background scan operation.
[c] The REASSIGN STATUS field in a given log parameter changes from 1h or 4h to 6h, 7h, or 8h when a reassign operation, write
medium operation based on the rules for caching, or unmap operation for the LBA succeeds or when a reassign operation for the
LBA fails. After the LBA is reassigned, any subsequent medium error occurring for the LBA is reported in a new log parameter with
the same value in the LOGICAL BLOCK ADDRESS field as the value in the LOGICAL BLOCK ADDRESS field in the log parameter
for the previous medium error for the LBA.
[d] The ARRE bit in the Read-Write Error Recovery mode page (see 4.3.16) controls automatic read reassignment based on errors
detected during all read operations, including those that are part of background scan operations.
SENSE KEY, ADDITIONAL SENSE CODE, and the ADDITIONAL SENSE CODE QUALIFIER fields
The SENSE KEY field, ADDITIONAL SENSE CODE field, and the ADDITIONAL SENSE CODE QUALIFIER field may contain a hierarchy
of additional information relating to error conditions that occurred during background scanning. They are represented in the same format
used by the sense data (see SPC-4).
LOGICAL BLOCK ADDRESS field
The LOGICAL BLOCK ADDRESS field indicates the LBA associated with the medium error.
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4.2.5

Cache Statistics page (37h)

Log Page code 37h specifies Cache Statistics page. The page format is shown in Table 256.
Table 255

Parameter codes

Parameter code

Resettable or
Changeable [a]

Description

0000h

This parameter code represents the number of logical blocks that have been
sent to a SCSI initiator port.

Reset
Only

0001h

This parameter code represents the number of logical blocks that have been
received from a SCSI initiator port.

Reset
Only

0002h

This parameter code represents the number of logical blocks read from the
cache memory that have been sent to a SCSI initiator port.

Reset
Only

0003h

This parameter code represents the number of READ and WRITE commands
that had data lengths equal or less than the current segment size.

Reset
Only

0004h

This parameter code represents the number of READ and WRITE commands
that had data lengths equal or less than the current segment size.

Reset
Only

[a] The keywords in this column -- Always, Reset Only, and Never -- are defined in 4.2.2.3.

Table 256

Cache Statistics page (37h)

Bit
Byte

7

6

0

DS

SPF (0b)

5

3

2

1

0

PAGE CODE (37h) (see 4.1.1)
SUBPAGE CODE(00h) (see 4.2.2.1)

1
2

4

(MSB)

PAGE LENGTH (see 4.1.1)

(LSB)

3
CACHE STATISTICS LOG PARAMETERS
4

(MSB)

PARAMETER CODE (see table 255)

(LSB)

...
PARAMETER CONTROL BYTE – binary format list log parameter (see 4.2.2.2.2.5)
...

DU

Obsolete

TSD

ETC

TMC

FORMAT AND LINKING

PARAMETER LENGTH

...
...

PARAMETER VALUE

...
...

...
...

(MSB)

PARAMETER CODE (see table 255)

(LSB)

...
PARAMETER CONTROL BYTE – binary format list log parameter (see 4.2.2.2.2.5)
...

DU

Obsolete

TSD

...
...

ETC

TMC

FORMAT AND LINKING

PARAMETER LENGTH
PARAMETER VALUE

n

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4.2.6

Error counter log pages (WRITE, READ, and VERIFY, 02h, 03h, and 05h)

This subclause defines the error counter log pages (see table 257).
Table 257

Error counter log page codes

Page Code

Loge Page Name

03h

Read Error Counter

05h

Verify Error Counter

02h

Write Error Counter

Table 258 defines the parameter codes for the error counter log pages.
Table 258

Parameter codes for error counter log pages

Parameter
code

Description

Resettable or
Changeable [a]

0000h

Errors corrected without substantial delay. An error correction was applied to get perfect data
(a.k.a., ECC on-the-fly). “Without Substantial Delay” means the correction did not postpone reading of later sectors (e.g., a revolution was not lost). The counter is incremented once for each logical block that requires correction. Two different blocks corrected during the same command are
counted as two events.

Reset
Only

0001h

Errors corrected with possible delays. An error code or algorithm (e.g.,ECC, checksum) is applied
in order to get perfect data with substantial delay. “With possible delay” means the correction took
longer than a sector time so that reading/writing of subsequent sectors was delayed (e.g, a lost
revolution). The counter is incremented once for each logical block that requires correction. A
block with a double error that is correctable counts as one event and two different blocks corrected
during the same command count as two events.

Reset
Only

0002h

Total (e.g., rewrites or rereads). This parameter code specifies the counter counting the number of
errors that are corrected by applying retries. This counts errors recovered, not the number of
retries. If five retries were required to recover one block of data, the counter increments by one,
not five. The counter is incremented once for each logical block that is recovered using retries. If
an error is not recoverable while applying retries and is recovered by ECC, it isn’t counted by this
counter; it will be counted by the counter specified by parameter code 01h–Error Corrected With
Possible Delay.

Reset
Only

0003h

Total errors corrected. This counter counts the total of parameter code errors 00h, 01h, and 02h.
There is to be no “double counting” of data errors among these three counters. The sum of all correctable errors can be reached by adding parameter code 01h and 02h errors, not by using this
total.

Reset
Only

0004h

Total times correction algorithm processed. This parameter code specifies the counter that counts
the total number of retries, or “times the retry algorithm is invoked.” If after five attempts a counter
02h type error is recovered, then five is added to this counter. If three retries are required to get a
stable ECC syndrome before a counter 01h type error is corrected, then those three retries are
also counted here. The number of retries applied to unsuccessfully recover an error (counter 06h
type error) are also counted by this counter.

Reset
Only

0005h

Total bytes processed. This parameter code specifies the counter that counts the total number of
bytes either successfully or unsuccessfully read, written, or verified (depending on the log page)
from the drive. If a transfer terminates early because of an unrecoverable error, only the logical
blocks up to and including the one with the unrecoverable error are counted.

Reset
Only

0006h

Total uncorrected errors. This parameter code specifies the counter that contains the total number
of blocks for which an uncorrected data error has occurred.

Reset
Only

0007h - 7FFFh

Reserved

8000h - FFFFh

Vendor specific

Reset
Only
Reset
Only

[a] The keywords in this column -- Always, Reset Only, and Never -- are defined in 4.2.2.3.
The exact definition of the error counters is not part of this manual. These counters should not be used to compare products because the
products may define errors differently.

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Table 259

Error counter log page

Bit
Byte

7

6

0

DS (1)

SPF (0)

5

3

2

1

0

PAGE CODE (see Table 257)
SUBPAGE CODE (00h) (see 4.2.2.1)

1
2

4

(MSB)

PAGE LENGTH (n-3)

3

(LSB)

Error counter log parameter
4

(MSB)

PARAMETER CODE (see table 258)

...
...

(LSB)

PARAMETER CONTROL BYTE – bounded data counter log parameter (see 4.2.2.2.2.2)
DU

Obsolete

TSD

ETC

TMC

...

PARAMETER LENGTH

...

PARAMETER VALUE

FORMAT AND LINKING

...
Error counter log parameter
...

(MSB)

PARAMETER CODE (see table 258)

...
...

(LSB)

PARAMETER CONTROL BYTE – bounded data counter log parameter (see 4.2.2.2.2.2)
DU

Obsolete

TSD

ETC

TMC

...

PARAMETER LENGTH

n

PARAMETER VALUE

FORMAT AND LINKING

The log page format is defined in 4.2.2. A log page may return one or more log parameters that record events defined by the parameter
codes.

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4.2.7

Factory Log page (3Eh)

Log page code 3Eh specifies factory status parameters (see table 260).
Table 260

Factory Log page (3Eh)

Bit
Byte

7

6

0

DS

SPF (0b)

5

3

2

1

SUBPAGE CODE(00h)
(MSB)

PAGE LENGTH

(LSB)

3
4

0

PAGE CODE (3Eh)

1
2

4

(MSB)

PARAMETER CODE [1] [2]

(LSB)

...
PARAMETER CONTROL BYTE – binary format list log parameter (see 4.2.2.2.2.5)
...

DU

Obsolete

TSD

ETC

TMC

FORMAT AND LINKING

PARAMETER LENGTH

...
...

PARAMETER VALUE

...
...

...
...

(MSB)

PARAMETER CODE

(LSB)

...
...

PARAMETER CONTROL BYTE – binary format list log parameter (see 4.2.2.2.2.5)
DU

Obsolete

TSD

...
...

ETC

TMC

FORMAT AND LINKING

PARAMETER LENGTH
PARAMETER VALUE

n
[1]
[2]

PARAMETER CODE 0000h–Power-on Time. This parameter code represents the number of drive power-on minutes.
PARAMETER CODE 08h. This parameter reports the time, in minutes, to the next scheduled interrupt for a S.M.A.R.T. measurement.

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4.2.8

Informational Exceptions log page (2Fh)

The Informational Exceptions log page (see table 262) provides a place for reporting detail about informational exceptions. The page code
for the Informational Exceptions log page is 2Fh.
Table 261 defines the parameter codes.
Table 261

Informational exceptions parameter codes

Parameter code

Description

Resettable or
Changeable [a]

Reference

Support
Required

Reset Only

4.2.6

Mandatory

Informational exceptions general parameter data

0000h
0001h - FFFFh

Vendor specific

[a] The keywords in this column – Always, Reset Only, and Never – are defined in 4.2.2.3.
The Informational Exceptions log page has the format shown in table 262.
Table 262
Bit
Byte
0
1
2
3
4
...
n

Informational Exceptions log page
7

6

DS

SPF (0b)

5

4

3

2

1

0

PAGE CODE (2Fh)
SUBPAGE CODE (00h)

(MSB)

PAGE LENGTH (n-3)

(LSB)

INFORMATIONAL EXCEPTIONS PARAMETERS
FIRST INFORMATIONAL EXCEPTIONS LOG PARAMETER
...
LAST INFORMATIONAL EXCEPTIONS LOG PARAMETER

PAGE CODE and PAGE LENGTH fields
The PAGE CODE and PAGE LENGTH fields are described in 4.2.2.

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The informational exceptions general parameter data page has the format shown in table 263.
Table 263
Bit
Byte
0
1
...
3
4
5
6
7
8
9
...
11

Informational exceptions general parameter data
7

6

5

(MSB)

DU

4

3

2

PARAMETER CODE (0000h)

1

0

(LSB)

PARAMETER CONTROL BYTE – binary format list log parameter (see 4.2.2.2.2.5)
Obsolete
TSD
ETC
TMC
FORMAT AND LINKING
PARAMETER LENGTH (N-3)
INFORMATIONAL EXCEPTION ADDITIONAL SENSE CODE
INFORMATIONAL EXCEPTION ADDITIONAL SENSE CODE QUALIFIER
MOST RECENT TEMPERATURE READING
VENDOR HDA TEMPERATURE TRIP POINT
MAXIMUM TEMPERATURE
Vendor specific

PARAMETER LENGTH field
The PARAMETER LENGTH field is described in 4.2.2. The parameter length shall be at least 04h.
INFORMATIONAL EXCEPTION ADDITIONAL SENSE CODE field
If the INFORMATIONAL EXCEPTION ADDITIONAL SENSE CODE field contains zero, no informational exception condition is pending
and contents of the INFORMATIONAL EXCEPTION ADDITIONAL SENSE CODE QUALIFIER field are unspecified. If the INFORMATIONAL EXCEPTION ADDITIONAL SENSE CODE field contains any value other than zero, an informational exception condition exists
that has an additional sense code indicated by INFORMATIONAL EXCEPTION ADDITIONAL SENSE CODE field and an ADDITIONAL
SENSE CODE QUALIFIER indicated by the INFORMATIONAL EXCEPTION ADDITIONAL SENSE CODE QUALIFIER field.
INFORMATIONAL EXCEPTION ADDITIONAL SENSE CODE QUALIFIER field
The INFORMATIONAL EXCEPTION ADDITIONAL SENSE CODE QUALIFIER field indicates detailed information related to the condition
reported in the INFORMATIONAL EXCEPTION ADDITIONAL SENSE CODE field. If the condition is reported by the device server, the
value returned shall be as defined in 2.4.1.5. If the device server does not have detailed information related to the reported condition, the
INFORMATIONAL EXCEPTION ADDITIONAL SENSE CODE QUALIFIER field shall be set to zero.
MOST RECENT TEMPERATURE READING field
The MOST RECENT TEMPERATURE READING field indicates the temperature in degrees Celsius of the SCSI target device at the time
the LOG SENSE command is performed. Temperatures equal to or less than zero degrees Celsius shall be indicated by a value of zero. If
the device server is unable to detect a valid temperature because of a sensor failure or other condition, the value returned shall be FFh.
The temperature should be reported with an accuracy of plus or minus three Celsius degrees while the device is operating at a steady
state within the environmental limits specified for the device.
VENDOR HDA TEMPERATURE TRIP POINT field
This field indicates the drive HDA temperature, in degrees Celsius, at which the drive will post a status with Sense Key of RECOVERED
ERROR or UNIT ATTENTION and ASC/ASCQ Warning—Specified Temperature Exceeded
MAXIMUM TEMPERATURE
Maximum Temperature field is the maximum temperature in degrees Celsius measured and logged by the device. This parameter value
never decreases. The parameter content of this field ranges from 00h to FFh.

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4.2.9

Non-Medium Error log page (06h)

4.2.9.1

Overview

The Non-Medium Error log page (page code 06h) provides for counting the occurrences of recoverable error events other than write, read,
or verify failures. No discrimination among the various types of events is provided by parameter code (see table 264). Vendor specific
discrimination may be provided through Seagate specific parameter codes.
Table 264

Non-medium error event parameter codes

Parameter code

Description
Non-medium error count

0000h
8000h - FFFFh

Resettable or
Changeable [a]

Reference

Support
Required

Reset Only

4.2.9

Mandatory

Vendor specific error counts
Reserved

All others

[a] The keywords in this column – Always, Reset Only, and Never – are defined in 4.2.2.3.
The Non-Medium Error log page has the format shown in table 265.
Table 265
Bit
Byte
0
1
2
3
4
...
n

Non-Medium Error log page
7

6

DS

SPF (0b)

5

(MSB)

4

3

2

1

0

PAGE CODE (06h)
SUBPAGE CODE (00h)
PAGE LENGTH (n-3)

(LSB)

NON-MEDIUM ERROR LOG PARAMETERS
FIRST NON-MEDIUM ERROR COUNT LOG PARAMETER (see table 264)
...
LAST NON-MEDIUM ERROR COUNT LOG PARAMETER (see table 264)

The DS bit, SPF bit, PAGE CODE field, SUBPAGE CODE field, and PAGE LENGTH field are described in 4.2.2.
The SPF bit, PAGE CODE field, and SUBPAGE CODE field shall be set as shown in table 265 for the Non-Medium Error log page.
The contents of each non-medium error log parameter depends on the value in its PARAMETER CODE field (see table 264).

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4.2.9.2

Non-Medium Error Count log parameter

The Non-Medium Error Count log parameter has the format shown in table 266.
Table 266

Non-Medium Error Count log parameter

Bit
Byte

7

6

0

(MSB)

5

4

3

2

1

0

PARAMETER CODE

1

(LSB)

PARAMETER CONTROL BYTE – bounded data counter log parameter (see 4.2.2.2.2.2)

2

DU

Obsolete

TSD

ETC

TMC

FORMAT AND LINKING

PARAMETER LENGTH (n - 3)

3
(MSB)

4

NON-MEDIUM ERROR COUNT

...

(LSB)

255
PARAMETER CODE field

The PARAMETER CODE field is described in 4.2.2.2.2, and shall be set as shown in table 266 for the Non-Medium Error Count log parameter.
DU bit, TSD bit, ETC bit, TMC field, and FORMAT AND LINKING field
The DU bit, TSD bit, ETC bit, TMC field, and FORMAT AND LINKING field are described in 4.2.2.2.2. These fields shall be set as
described for a bounded data counter log parameter (see 4.2.2.2.2.2) for the Non-Medium Error Count log parameter.
PARAMETER LENGTH field
The PARAMETER LENGTH field is described in 4.2.2.2.1.
NON-MEDIUM ERROR COUNT field
The NON-MEDIUM ERROR COUNT field indicates the number of recoverable error events other than read, read reverse, verify, or write
failures.
4.2.10

Power Condition Transitions log page (1Ah)

4.2.10.1

Overview

Using the format shown in table 268, the Power Condition Transitions log page (page code 1Ah) provides a count of the occurrences of
power condition transition events using the parameter codes listed in table 267.
Table 267
Parameter
code

Power Condition Transitions log page parameter codes
Description

0001h

Accumulated transitions to active

0002h

Accumulated transitions to idle_a

0003h

Accumulated transitions to idle_b

0004h

Accumulated transitions to idle_c

0008h

Accumulated transitions to standby_z

0009h

Accumulated transitions to standby_y

all others

Resettable or
Changeable [a]

Reference

Support
requirements
Mandatory

Never

At least one [b]

Reserved

[a] The keywords in this column – Always, Reset Only, and Never – are defined in 4.2.2.3.
[b] If the Power Conditions Transitions log page is supported, at least one of these parameter codes shall be supported.

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4.2.10.2

Power Condition Transitions log page (1Ah)

The Power Condition Transitions log page (see Table 268) provides a count of the occurrences of power condition transition events. A
device server that implements the Power Condition Transitions log page shall implement one or more of the defined parameters.
Table 268
Bit
Byte
0
1
2
3

Power Condition Transitions log page
7

6

5

DS

SPF (0b)

4

3

2

1

0

PAGE CODE (1Ah)
SUBPAGE CODE(00h)

(MSB)

PAGE LENGTH (n-3)

(LSB)

POWER CONDITION TRANSITIONS LOG PARAMETERS
4
FIRST POWER CONDITION TRANSITIONS LOG PARAMETER (see table 269)
...

...

LAST POWER CONDITION TRANSITIONS LOG PARAMETER (see table 269)
n
DS bit, SPF bit, PAGE CODE field, SUBPAGE CODE and PAGE LENGTH field
The DS bit, SPF bit, PAGE CODE field and PAGE LENGTH field are described in 4.2.2.
The format for all log parameters in the Power Condition Transitions log page is shown in table 269. All log parameters in the Power
Condition Transitions log page contain a four-byte binary value.
Table 269
Bit
Byte
0
1
2
3
4
...
7

Power Condition Transitions log parameter format
7

6

(MSB)

DU

5

4

3

PARAMETER CODE (see table 270)

2

1

0

(LSB)

PARAMETER CONTROL BYTE – binary format list log parameter (see 4.2.2.2.2.5)
Obsolete
TSD
ETC
TMC
FORMAT AND LINKING
PARAMETER LENGTH (04h)

(MSB)
PARAMETER VALUE
(LSB)

All Power Condition Transitions log page counters are saturating counters (see Table 242 field descriptors). A count is incremented by one
for each transition (see table 270). The time in the transition at which the count is incremented is vendor specific.
If a LOG SELECT command attempts to change the value of any log parameter in the Power Condition Transitions log page, the command
shall be terminated with CHECK CONDITION status, with sense key set to ILLEGAL REQUEST and additional sense code set to INVALID
FIELD IN PARAMETER LIST.
DU bit, TSD bit, ETC bit, TMC field, and FORMAT AND LINKING
The DU bit, TSD bit, ETC bit, TMC field, and FORMAT AND LINKING field are collectively referred to as the parameter control byte as
described in 4.2.2.2.2.5.
PARAMETER LENGTH field
The PARAMETER LENGTH field shall be set as shown in Table 269 and specifies the length in bytes of the PARAMETER VALUE field that
follows. If the application client specifies a parameter length that results in the truncation of the PARAMETER VALUE field, the command
shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to
INVALID FIELD IN PARAMETER LIST.
PARAMETER VALUE field
The PARAMETER VALUE field contains a saturating counter as described in Table 269 for the corresponding parameter code value in the
Power Condition Transitions log parameter PARAMETER CODE field (see Table 268).
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4.2.11

Protocol-Specific Port log page (18h)

The Protocol-Specific Port log page for SAS SSP defined in Table 270 is used to return information about phy events concerning the SAS
target device’s phy(s).
A phy is defined as an object in a device that is used to interface to other devices.
Table 270
Bit
Byte
0
1
2
3

Protocol-Specific Port log page for SAS SSP
7

6

5

DS

SPF (0b)

4

3

2

1

0

PAGE CODE (18h)
SUBPAGE CODE (00h)

(MSB)

PAGE LENGTH (n-3)

(LSB)

PROTOCOL-SPECIFIC PORT LOG PARAMETER LIST
4
...
...
...
n

PROTOCOL-SPECIFIC PORT LOG PARAMETER (first) (see table 271)
...
PROTOCOL-SPECIFIC PORT LOG PARAMETER (last) (see table 271)

DS bit, SPF bit, PAGE CODE field, SUBPAGE CODE and PAGE LENGTH field
The DS bit, SPF bit, PAGE CODE field, SUBPAGE CODE and PAGE LENGTH field are described in 4.2.2.
The protocol-specific port log parameter list contains a protocol-specific port log parameter for each SCSI port in the SAS target device.
Table 271 defines the format for the Protocol-Specific Port log parameter for SAS. The SAS log parameter is a list parameter (i.e., not a
data counter) and only has cumulative (i.e., not threshold) values (see SPC-4).
Table 271

Protocol-Specific Port log parameter for SAS

Bit
Byte

7

0

(MSB)

6

5

3

2

1

PARAMETER CODE (relative target port identifier)

1
2

4

0

(LSB)

PARAMETER CONTROL BYTE – binary format list log parameter (see 4.2.2.2.2.5)
DU

Obsolete

TSD

4

ETC

TMC

FORMAT AND LINKING

PARAMETER LENGTH (y-3)

3
Reserved

PROTOCOL IDENTIFIER (6h)

5

Reserved

6

GENERATION CODE

7

NUMBER OF PHYS
SAS PHY LOG DESCRIPTOR LIST

8
...

SAS PHY LOG DESCRIPTOR (first) (see table 272)

8+m
...

...
y-m
...

SAS PHY LOG DESCRIPTOR (last) (see table 272)

y
PARAMETER CODE field
The PARAMETER CODE field is defined in Section 4.2.2.2 and contains the relative target port identifier (see SPC-4) of the SSP target
port that the log parameter describes.
DU bit, TSD bit, ETC bit, TMC field, and FORMAT AND LINKING
The DU bit, TSD bit, ETC bit, TMC field, and FORMAT AND LINKING field are collectively referred to as the parameter control byte as
described in 4.2.2.2.2.5.
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PARAMETER LENGTH field
The PARAMETER LENGTH field is defined in Section 4.2.2.2 and shall be set to the value defined in Table 271.
PROTOCOL IDENTIFIER field
The PROTOCOL IDENTIFIER field is defined in Section 4.3.17.1.1 and shall be set to the value defined in Table 271.
GENERATION CODE field
The GENERATION CODE field is defined in the Phy Control and Discover mode page (Section 4.3.18.3.4).
NUMBER OF PHYS field
The NUMBER OF PHYS field contains the number of phys in the SAS target port (not in the entire SAS target device) and indicates the
number of SAS phy log descriptors in the SAS phy log descriptor list.
The SAS phy log descriptor list contains SAS phy log descriptors.
Table 272 defines the SAS phy log descriptor.
Table 272
Bit
Byte
0
1
2
3
4
5

SAS phy log descriptor
7

Reserved

6

7
8
...
15
16
...
23
24
25
31
32
...
35
36
...
39
40
...
43
44
...
47
48
49
50

6

5

4

3

2

1

0

Reserved
PHY IDENTIFIER
Reserved
SAS PHY LOG DESCRIPTOR LENGTH (m - 3)
ATTACHED DEVICE TYPE
ATTACHED REASON
REASON
NEGOTIATED LOGICAL LINK RATE
ATTACHED
ATTACHED
ATTACHED
SSP
STP
SMP
Reserved
Reserved
INITIATOR
INITIATOR
INITIATOR
PORT
PORT
PORT
ATTACHED
ATTACHED
ATTACHED
SSP
STP
SMP
Reserved
Reserved
TARGET
TARGET
TARGET
PORT
PORT
PORT
SAS ADDRESS

ATTACHED SAS ADDRESS
ATTACHED PHY IDENTIFIER
Reserved
(MSB)
INVALID DWORD COUNT
(LSB)
(MSB)
RUNNING DISPARITY ERROR COUNT
(LSB)
(MSB)
LOSS OF DWORD SYNCHRONIZATION
(LSB)
(MSB)

SCSI Commands Reference Manual, Rev. H

PHY RESET PROBLEM
(LSB)
Reserved
PHY EVENT DESCRIPTOR LENGTH
236

Table 272

SAS phy log descriptor

Bit
Byte

7

6

5

4

3

2

1

0

NUMBER OF PHY EVENT DESCRIPTORS

51

PHY EVENT DESCRIPTOR LIST
52
...
63
...
m-11
...
M

PHY EVENT DESCRIPTOR (first) (see table 276)
...
PHY EVENT DESCRIPTOR (last) (see table 276)

PHY IDENTIFIER field
The PHY IDENTIFIER field specifies the phy identifier of the phy that is to perform or to stop performing a phy test function (i.e., the
selected phy). If the PHY IDENTIFIER field specifies a phy that does not exist, then the device server shall terminate the SEND DIAGNOSTIC command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to
INVALID FIELD IN PARAMETER LIST.
SAS PHY LOG DESCRIPTOR LENGTH field
The SAS PHY LOG DESCRIPTOR LENGTH field indicates the number of bytes that follow in the SAS phy log descriptor and shall be set
to the value defined in Table 272. A SAS PHY LOG DESCRIPTOR LENGTH field set to 00h indicates that there are 44 additional bytes.

Note.

Logical units compliant with SAS and SAS-1.1 only support a 48 byte SAS phy log descriptor.

ATTACHED DEVICE TYPE field
The ATTACHED DEVICE TYPE field indicates the type of device attached to this phy, and is defined in Table 273.
Table 273

Device type field

Code

Description

001b

End device

010b

Expander device

011b

Expander device compliant with a previous version of the SAS standard

All others

Reserved

ATTACHED REASON field
The ATTACHED REASON field indicates the reason received from the attached device for the link reset sequence and is defined in Table
274

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REASON field
The REASON field indicates the reason sent by the target device for the last link reset sequence and is defined in table 258.
Table 274

Reason field definition

Code

Description

0h

Unknown reason

1h

Power on

2h

Hard reset (e.g., the port containing this phy received a HARD_RESET primitive during the hard
reset sequence) (see SPL-3 r02, Section 4.4.2), or SMP PHY CONTROL function HARD
RESET phy operation (see SPL-3 r02, Section 9.4.3.28)

3h

SMP PHY CONTROL function LINK RESET phy operation, or TRANSMIT SATA PORT SELECTION SIGNAL phy operation (see SPL-3 r02, Section 9.4.3.28)

4h

Loss of dword synchronization (see SPL-3 r02, Section 5.13)

5h

After the multiplexing sequence completes, MUX (LOGICAL LINK 0) received in logical link 1 or
MUX (LOGICAL LINK 1) received in logical link 0 (see SPL-3 r02, Section 5.15)

6h

I_T nexus loss timer expired in the STP target port of an STP/SATA bridge when the phy was
attached to a SATA device (see SPL-3 r02, Section 4.4.3)

7h

Break Timeout Timer expired (see SPL-3 r02, Section 6.14.8)

8h

Phy test function stopped (see SPL-3 r02, Section 9.4.3.29)

9h

Expander device reduced functionality (see SPL-3 r02, Section 4.5.8)

Ah to Fh

Reserved

NEGOTIATED LOGICAL LINK RATE field
The NEGOTIATED LOGICAL LINK RATE field is defined in Table 275 and indicates the logical link rate being used by the phy. For physical
phys, this is negotiated during the link reset sequence. For virtual phys, this field should be set to the maximum physical link rate supported
by the expander device. This field may be different from the negotiated physical link rate when multiplexing is enabled.
Table 275

NEGOTIATED LOGICAL LINK RATE field

NEGOTIATED PHYSICAL LINK RATE field
9h (i.e., G2)

Ah (i.e., G3)

Bh (i.e., G4)

All others

Note.

Multiplexing

NEGOTIATED LOGICAL LINK RATE field

Disable

9h (i.e., 3Gb/s)

Enable

8h (i.e., 1.5Gb/s)

Disable

Ah (i.e., 6Gb/s)

Enable

9h (i.e., 3Gb/s)

Disable

Bh (i.e., 12Gb/s)

Enable

Ah (i.e., 6Gb/s)

Any

Same as the NEGOTIATED LOGICAL LINK RATE
field

In previous versions of the SAS standard that did not define multiplexing, the NEGOTIATED LOGICAL LINK RATE field was
called the NEGOTIATED PHYSICAL LINK RATE field and the NEGOTIATED PHYSICAL LINK RATE field in byte 94 did not
exist.

ATTACHED SSP INITIATOR PORT bit
1

An ATTACHED SSP INITIATOR PORT bit set to one indicates that an SSP initiator port is present in the attached device.

0

An ATTACHED SSP INITIATOR PORT bit set to zero indicates that an SSP initiator port is not present in the attached device.

ATTACHED STP INITIATOR PORT bit
1

An ATTACHED STP INITIATOR PORT bit set to one indicates that an STP initiator port is present in the attached device.

0

An ATTACHED STP INITIATOR PORT bit set to zero indicates that an STP initiator port is not present in the attached device.

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ATTACHED SMP INITIATOR PORT bit
1

An ATTACHED SMP INITIATOR PORT bit set to one indicates that an SMP initiator port is present in the attached device.

0

An ATTACHED SMP INITIATOR PORT bit set to zero indicates that an SMP initiator port is not present in the attached device.

ATTACHED SSP TARGET PORT bit
1

An ATTACHED SSP TARGET PORT bit set to one indicates that an SSP target port is present in the attached device.

0

An ATTACHED SSP TARGET PORT bit set to zero indicates that an SSP target port is not present in the attached device.

ATTACHED STP TARGET PORT bit
1

An ATTACHED STP TARGET PORT bit set to one indicates that an STP target port is present in the attached device.

0

An ATTACHED STP TARGET PORT bit set to zero indicates that an STP target port is not present in the attached device.

ATTACHED SMP TARGET PORT bit
1

An ATTACHED SMP TARGET PORT bit set to one indicates that an SMP target port is present in the attached device.

0

An ATTACHED SMP TARGET PORT bit set to zero indicates that an SMP target port is not present in the attached device.

SAS ADDRESS field
The SAS ADDRESS field indicates the port identifier (see SPL-3 r02, Section 4.2.9) of the SAS port transmitting the IDENTIFY address
frame. For expander ports, the SAS ADDRESS field indicates the device name (see SPL-3 r02, Section 4.2.6) of the expander device
transmitting the IDENTIFY address frame.
ATTACHED SAS ADDRESS field
The ATTACHED SAS ADDRESS field contains SAS address of the attached SAS port (see SPL-3 r02, Section 4.2.9).
ATTACHED PHY IDENTIFIER field
The ATTACHED PHY IDENTIFIER field contains the phy identifier of the attached SAS phy in the attached SAS device.
INVALID DWORD COUNT field
The INVALID DWORD COUNT field indicates the number of invalid dwords (see (see SPL-3 r02, Section 3.1.99) that have been received
outside of phy reset sequences (i.e., between when the SP state machine (see SPL-3 r02, Section 5.12) sends a Phy Layer Ready (SAS)
confirmation or Phy Layer Ready (SATA) confirmation and when it sends a Phy Layer Not Ready confirmation to the link layer). The count
shall stop at the maximum value. The INVALID DWORD COUNT field is set to a vendor-specific value after power on.
For the INVALID DWORD COUNT field, RUNNING DISPARITY ERROR COUNT field, LOSS OF DWORD SYNCHRONIZATION COUNT
field, and PHY RESET PROBLEM COUNT field, the phy may maintain any size counter but should maintain a 32-bit counter. If it reaches
its maximum value, then the counter shall stop and the device server shall set the field to FFFFFFFFh in the SAS phy log descriptor.
RUNNING DISPARITY ERROR COUNT field
The RUNNING DISPARITY ERROR COUNT field indicates the number of dwords containing running disparity errors (see SPL-3 r02,
Section 5.3.5) that have been received outside of phy reset sequences. The count shall stop at the maximum value. The RUNNING
DISPARITY ERROR COUNT field is set to a vendor-specific value after power on.
LOSS OF DWORD SYNCHRONIZATION COUNT field
The LOSS OF DWORD SYNCHRONIZATION COUNT field indicates the number of times the phy has restarted the link reset sequence
because it lost dword synchronization (see SPL-3 r02, Section 5.13) (i.e., the SP state machine transitioned from SP15:SAS_PHY_Ready
or SP22:SATA_PHY_Ready to SP0:OOB_COMINIT (see SPL-3 r02, Section 5.12)). The count shall stop at the maximum value. The
LOSS OF DWORD SYNCHRONIZATION COUNT field is set to a vendor-specific value after power on.
PHY RESET PROBLEM COUNT field
The PHY RESET PROBLEM COUNT field indicates the number of times a phy reset problem (see SPL-3 r02, Section 5.10.4.2.4)
occurred. The count shall stop at the maximum value. The PHY RESET PROBLEM COUNT field is set to a vendor-specific value after
power on.
PHY EVENT DESCRIPTOR LENGTH field
The PHY EVENT DESCRIPTOR LENGTH field indicates the number of bytes in the phy event descriptor (see SPL-3 r02, Section
9.4.3.14.4).
NUMBER OF PHY EVENT DESCRIPTORS field
The NUMBER OF PHY EVENT DESCRIPTORS field indicates the number of phy event descriptors in the phy event descriptor list.
Each PHY EVENT DESCRIPTOR follows the format defined for the SMP REPORT PHY EVENT function in (see SPL-3 r02, Section
9.4.3.14.4).
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4.2.11.1

Phy event descriptor

Table 4.2.11.1 defines the phy event descriptor.
Table 276
Bit
Byte

Phy event descriptor
7

6

5

4

3

2

1

0

0
Reserved

...
2

PHY EVENT SOURCE

3
4

(MSB)
PHY EVENT

...

(LSB)

7
8

(MSB)

...

PEAK VALUE DETECTOR THRESHOLD

11

(LSB)

PHY EVENT SOURCE field
The PHY EVENT SOURCE field, defined in SAS-3, indicates the type of phy event being reported in the PHY EVENT field.
PHY EVENT field
The PHY EVENT field indicates the value (i.e., the count or peak value detected) of the phy event indicated by the PHY EVENT SOURCE
field.
PEAK VALUE DETECTOR THRESHOLD field
If the phy event source is a peak value detector, then the PEAK VALUE DETECTOR THRESHOLD field indicates the value of the peak
value detector that causes the expander device to originate a Broadcast (Expander) (see SAS-3). If the phy event source is not a peak
value detector, then the PEAK VALUE DETECTOR THRESHOLD field is reserved.

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4.2.12

Self-Test Results log page (10h)

The Self-Test Results log page (see table 277) provides the results from the 20 most recent self-tests (see 3.47). Results from the most
recent self-test or the self-test currently in progress shall be reported in the first self-test log parameter; results from the second most
recent self-test shall be reported in the second self-test log parameter; etc. If fewer than 20 self-tests have occurred, the unused self-test
log parameter entries shall be zero filled.
Table 277

Self-Test Results log page

Bit
Byte

7

6

5

0

DS

SPF (0b)

3

2

1

0

PAGE CODE (10h)
SUBPAGE CODE (00h) (see 4.2.2.1)

1
2

4

(MSB)

PAGE LENGTH (190h)

3

(LSB)

SELF-TEST RESULTS LOG PARAMETERS
4

FIRST SELF-TEST RESULTS LOG PARAMETER
(most recent)

...
23

...

...
384

TWENTIETH SELF-TEST RESULTS LOG PARAMETER
(least recent)

...
403

DS bit, SPF bit, PAGE CODE field and PAGE LENGTH field
The DS bit, SPF bit, PAGE CODE field and PAGE LENGTH field are described in 4.2.2.
Table 278 shows the format of one self-test log parameter.
Table 278
Bit
Byte
0
1
...
3
4
5
6
7
8
...
15
16
17
18
19

Self-test results log parameter format
7

6

5

(MSB)

DU

4

3

2

1

0

PARAMETER CODE (0001h TO 0014h)

(LSB)
PARAMETER CONTROL BYTE – binary format list log parameter (see 4.2.2.2.2.5)
Obsolete
TSD
ETC
TMC
FORMAT AND LINKING
PARAMETER LENGTH (10h)
SELF-TEST CODE
Reserved
SELF-TEST RESULTS
SELF-TEST NUMBER

(MSB)

ACCUMULATED POWER ON HOURS

(LSB)

(MSB)
ADDRESS OF FIRST FAILURE
(LSB)
Reserved

SENSE KEY
ADDITIONAL SENSE CODE
ADDITIONAL SENSE CODE QUALIFIER
Vendor specific

PARAMETER CODE field
The PARAMETER CODE field identifies the log parameter being transferred. The PARAMETER CODE field for the results of the most
recent self-test shall contain 0001h; the PARAMETER CODE field for the results of the second most recent test shall contain 0002h; etc.
PARAMETER LENGTH field
The PARAMETER LENGTH field shall contain 10h.

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SELF-TEST CODE field
The SELF-TEST CODE field contains the value in the SELF-TEST CODE field of the SEND DIAGNOSTIC command that initiated this selftest.
Table 279 defines the content of the SELF-TEST RESULTS field.
Table 279

SELF-TEST RESULTS field

Code

Description

0h

The self-test completed without error.

1h

The background self-test was aborted by the application client using a SEND DIAGNOSTIC command (see
3.47) with the SELF-TEST CODE field set to 100b (i.e., abort background self-test).

2h

The self-test routine was aborted by an application client using a method other than a SEND DIAGNOSTIC
command with the SELF-TEST CODE field set to 100b (e.g., by a task management function, or by issuing an
exception command as defined in SPC-4).

3h

An unknown error occurred while the device server was processing the self-test and the device server was
unable to complete the self-test.

4h

The self-test completed with a failure in a test segment, and the test segment that failed is not known.

5h

The first segment of the self-test failed.

6h

The second segment of the self-test failed.

7h

Another segment of the self-test failed and which test is indicated by the contents of the SELF-TEST NUMBER
field.

8h-Eh
Fh

Reserved
The self-test is in progress.

SELF-TEST NUMBER field
The SELF-TEST NUMBER field identifies the self-test that failed and consists of either:
a) The number of the segment that failed during the self-test; or
b) The number of the test that failed and the number of the segment in which the test was run, using a vendor specific method for
placing the two values in the one field.
When the segment in which the failure occurred is not able to be identified or need not be identified, the SELF-TEST NUMBER field shall
contain 00h.
ACCUMULATED POWER ON HOURS field
The ACCUMULATED POWER ON HOURS field contains the total hours for the device server has been powered on since manufacturing
at the time the self-test is completed. If the test is still in progress, the content of the ACCUMULATED POWER ON HOURS field shall be
zero. If the power-on hours for the device server at the time the self-test was completed is greater than FFFFh then the content of the
ACCUMULATED POWER ON HOURS field shall be FFFFh.
ADDRESS OF FIRST FAILURE field
The ADDRESS OF FIRST FAILURE field contains information that locates the failure on the media. If the logical unit implements logical
blocks, the content of the ADDRESS OF FIRST FAILURE field is the first logical block address where a self-test error occurred. This
implies nothing about the quality of any other logical block on the logical unit, since the testing during which the error occurred may not
have been performed in a sequential manner. This value shall not change (e.g., as the result of block reassignment). The content of the
ADDRESS OF FIRST FAILURE field shall be FFFF FFFF FFFF FFFFh if no errors occurred during the self-test or if the error that occurred
is not related to an identifiable media address.
SENSE KEY, ADDITIONAL SENSE CODE, and ADDITIONAL SENSE CODE QUALIFIER fields
The SENSE KEY field, ADDITIONAL SENSE CODE field, and ADDITIONAL SENSE CODE QUALIFIER field may contain a hierarchy of
additional information relating to error or exception conditions that occurred during the self-test represented in the same format used by the
sense data (see Section 3.38, "REQUEST SENSE command.").

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4.2.13

Solid State Media log page (11h)

4.2.13.1

Overview

Using the format shown in Table 281, the Solid State media log page (PAGE CODE 11h) reports parameters that are specific to SCSI target devices that contain solid state media. The parameter codes for the Solid State Media log page are listed in Table 280.
Table 280

Solid State Media log parameters

Parameter code

Description

Resettable or
Changeable [a]

Support
requirements

0001h

Percentage Used Endurance Indicator

Never

Mandatory

all others

Reserved

[a] The keywords in this column – Always, Reset Only, and Never – are defined in 4.2.2.3.
The Solid State Media log page has the format shown in Table 281.
Table 281

Solid State Media log page

Bit
Byte

7

6

5

0

DS

SPF (0b)

3

2

1

0

PAGE CODE (11h)
SUBPAGE CODE(00h)

1
2

4

(MSB)

PAGE LENGTH (n - 3)

3

(LSB)

SOLID STATE MEDIA LOG PARAMETERS (see table 280)
4

SOLID STATE MEDIA PARAMETER (first

...

...

n

SOLID STATE MEDIA PARAMETER (last)

DS bit, SPF bit, PAGE CODE field, SUBPAGE CODE and PAGE LENGTH field
The DS bit, SPF bit, PAGE CODE field, SUBPAGE CODE and PAGE LENGTH field are described in 4.2.2.

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4.2.13.2

Percentage Used Endurance Indicator log parameter

The Percentage Used Endurance Indicator log parameter has the format shown in Table 282.
Table 282

Percentage Used Endurance Indicator log parameter format

Bit
Byte

7

0

(MSB)

6

5

3

2

1

PARAMETER CODE (0001h)

1
2

4

0

(LSB)

PARAMETER CONTROL BYTE – binary format list log parameter (see 4.2.2.2.2.5)
DU

Obsolete

TSD

ETC

TMC

FORMAT AND LINKING

PARAMETER LENGTH (04h)

3
4

RESERVED

...
6
7

PERCENTAGE USED ENDURANCE INDICATOR

PARAMETER CODE field
The PARAMETER CODE field is described in SPC-4 and shall be set to the value shown in table 169 for the Percentage Used Endurance
Indicator log parameter.
DU bit, the TSD bit, the ETC bit, the TMC field, and the FORMAT AND LINKING field
The DU bit, the TSD bit, the ETC bit, the TMC field, and the FORMAT AND LINKING field for the Percentage Used Endurance Indicator log
parameter shall be set for a binary format list log parameter as described in 4.2.2.2.2.5.
PARAMETER LENGTH field
The PARAMETER LENGTH field is described in SPC-4 and shall be set to the value shown in table 169 for the Percentage Used Endurance Indicator log parameter.
PERCENTAGE USED ENDURANCE INDICATOR field
The PERCENTAGE USED ENDURANCE INDICATOR field indicates an estimate of the percentage of device life that has been used. The
value in the field shall be set to zero at the time of manufacture. A value of 100 indicates that the estimated endurance of the device has
been consumed, but may not indicate a device failure (e.g., minimum power-off data retention capability reached for devices using flash
technology). The value is allowed to exceed 100. Values greater than 254 shall be reported as 255. The device server shall update the
value at least once per power-on hour.

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4.2.14

Start-Stop Cycle Counter log page (0Eh)

4.2.14.1

Overview

Using the format shown in table 284, the Start-Stop Cycle Counter log page (page code 0Eh) provides information about manufacturing
dates and cycle counts since date of manufacture using the parameter codes listed in table 283.
Table 283

Solid State Media log parameters

Parameter
code

Resettable or
Changeable [a]

Description

0001h

Date of Manufacture

0002h

Accounting Date

0003h

Specified Cycle Count Over Device Lifetime

Never

0004h

Accumulated Start-Stop Cycles

Never

0005h

Specified Load-Unload Count Over Device Lifetime

Never

0006h

Accumulated Load-Unload Cycles

Never

all others

Never
Always

Reserved

[a] The keywords in this column – Always, Reset Only, and Never – are defined in 4.2.2.3.
The Start-Stop Cycle Counter log page has the format shown in table 284.
Table 284
Bit
Byte
0
1
2
3
4
5
6
7
8
...
11
12
13
14
15
16
17
18
...
21
22
23
24
25
26
27

Start-Stop Cycle Counter log page (Sheet 1 of 2)
7

6

DS

SPF (0b)

5

3

2

1

0

PAGE CODE (0Eh)
SUBPAGE CODE(00h)

(MSB)

PAGE LENGTH (n-3)

(MSB)

DU

4

(LSB)

PARAMETER CODE 0001h
DATE OF MANUFACTURE

(LSB)
PARAMETER CONTROL BYTE – ASCII format list log parameter (see 4.2.2.2.2.4)
Obsolete
TSD
ETC
TMC
FORMAT AND LINKING
PARAMETER LENGTH (06h)

(MSB)
YEAR OF MANUFACTURE (4 ASCII CHARACTERS)
(LSB)
(MSB)

WEEK OF MANUFACTURE (2 ASCII CHARACTERS)

(MSB)

DU

PARAMETER CODE 0002h
ACCOUNTING DATE

(LSB)
(LSB)

PARAMETER CONTROL BYTE – ASCII format list log parameter (see 4.2.2.2.2.4)
Obsolete
TSD
ETC
TMC
FORMAT AND LINKING
PARAMETER LENGTH (06h)

(MSB)
ACCOUNTING DATE YEAR (4 ASCII CHARACTERS)
(LSB)
(MSB)
(MSB)

DU

ACCOUNTING DATE WEEK (2 ASCII CHARACTERS)
PARAMETER CODE 0003h
SPECIFIED CYCLE COUNT OVER DEVICE LIFETIME

(LSB)
(LSB)

PARAMETER CONTROL BYTE – binary format list log parameter (see 4.2.2.2.2.5)
Obsolete
TSD
ETC
TMC
FORMAT AND LINKING
PARAMETER LENGTH (04h)

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Table 284
Bit
Byte
28
..
31
32
33
34
35
36
...
39
40
41
42
43
44
...
47
48
49
50
51
52
...
55

Start-Stop Cycle Counter log page (Sheet 2 of 2)
7
(MSB)

6

5

DU
(MSB)

(MSB)

DU
(MSB)

2

PARAMETER CODE 0004h
ACCUMULATED START-STOP CYCLES

1

0

(LSB)
(LSB)

PARAMETER CONTROL BYTE – binary format list log parameter (see 4.2.2.2.2.5)
Obsolete
TSD
ETC
TMC
FORMAT AND LINKING
PARAMETER LENGTH (04h)

(MSB)

(MSB)

3

SPECIFIED CYCLE COUNT OVER DEVICE LIFETIME
(4-BYTE BINARY NUMBER)

(MSB)

DU

4

ACCUMULATED START-STOP CYCLES
(4-BYTE BINARY NUMBER)

(LSB)

PARAMETER CODE 0005h
SPECIFIED LOAD-UNLOAD COUNT OVER DEVICE LIFETIME

(LSB)
PARAMETER CONTROL BYTE – binary format list log parameter (see 4.2.2.2.2.5)
Obsolete
TSD
ETC
TMC
FORMAT AND LINKING
PARAMETER LENGTH (04h)
SPECIFIED LOAD-UNLOAD COUNT OVER DEVICE LIFETIME
(4-BYTE BINARY NUMBER)

(LSB)

PARAMETER CODE 0006h
ACCUMULATED LOAD-UNLOAD CYCLES

(LSB)
PARAMETER CONTROL BYTE – binary format list log parameter (see 4.2.2.2.2.5)
Obsolete
TSD
ETC
TMC
FORMAT AND LINKING
PARAMETER LENGTH (04h)
ACCUMULATED LOAD-UNLOAD CYCLES
(4-BYTE BINARY NUMBER)

(LSB)

The year and week in the year that the SCSI target device was manufactured shall be contained in the parameter value of the log
parameter in which the parameter code is 0001h. The date of manufacture shall not be saveable by the application client using the LOG
SELECT command (i.e., the log parameter DS bit shall be set to one). The date is expressed in numeric ASCII characters (30h – 39h) in
the form YYYYWW, as shown in table 284.
The accounting date specified by parameter code 0002h may be saved using a LOG SELECT command to indicate when the device was
placed in service. If the parameter is not yet set or is not settable, the default value placed in the parameter field shall be 6 ASCII space
characters (20h). The field shall not be checked for validity by the device server.
The parameter value in the specified cycle count over device lifetime log parameter (parameter code 0003h) shall contain a four-byte
binary value that indicates how many stop-start cycles may typically be performed over the lifetime of the SCSI target device without
degrading the SCSI target device’s operation or reliability outside the limits specified by the manufacturer of the SCSI target device. The
specified cycle count over device lifetime parameter shall not be saveable by the application client using the LOG SELECT command (i.e.,
the log parameter DS bit shall be set to one).
The parameter value in the accumulated start-stop cycles log parameter (parameter code 0004h) shall contain a four-byte binary value that
indicates how many stop-start cycles the SCSI target device has detected since its date of manufacture. The accumulated start-stop cycles
parameter shall not be saveable by the application client using the LOG SELECT command (i.e., the log parameter DS bit shall be set to
one). The time at which the count is incremented during a start-stop cycle is vendor specific. For rotating magnetic storage devices, a
single start-stop cycle is defined as an operational cycle that begins with the disk spindle at rest, continues while the disk accelerates to its
normal operational rotational rate, continues during the entire period the disk is rotating, continues as the disk decelerates toward a resting
state, and ends when the disk is no longer rotating. For devices without a spindle or with multiple spindles, the definition of a single startstop cycle is vendor specific. The count is incremented by one for each complete start-stop cycle. No comparison with the value of
parameter 0003h shall be performed by the device server.
The parameter value in the specified load-unload count over device lifetime log parameter (parameter code 0005h) shall contain a fourbyte binary value that indicates how many load-unload cycles may be performed over the lifetime of the SCSI target device without
degrading the SCSI target device's operation or reliability outside the limits specified by the manufacturer of the SCSI target device. The
specified load-unload count parameter shall not be saveable by the application client using the LOG SELECT command (i.e., the log
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parameter DS bit shall be set to one). The time at which the count is incremented during a specified load-unload count is vendor specific.
For rotating magnetic storage devices, a single load-unload cycle is defined as an operational cycle that begins with the disk spindle at
rest, continues while the disk accelerates to its normal operational rotational rate, continues during the entire period the disk is rotating,
continues as the disk decelerates toward a resting state, and ends when the disk is no longer rotating. For devices without a spindle or with
multiple spindles, the definition of a single load-unload cycle is vendor specific. The count is incremented by one for each complete loadunload cycle. No comparison with the value of parameter 0005h shall be performed by the device server.
The parameter value in the accumulated load-unload count over device lifetime log parameter (parameter code 0006h) shall contain a fourbyte binary value that indicates the SCSI target device has detected since its date of manufacture. This saturating counter is incremented
by one for each complete cycle. The time in the cycle at which the counter is incremented is vendor specific.
For rotating magnetic storage devices (see SBC-3), a single load-unload cycle is defined as an operational cycle that:
a) begins with the heads unloaded from the medium;
b) continues while the heads are loaded onto the spinning medium; and
c) ends when the heads are unloaded from the medium.
The Accumulated Load-Unload Cycles log parameter is not applicable to rotating magnetic storage devices without unloadable heads.
The device server shall not compare the contents of the ACCUMULATED LOAD-UNLOAD CYCLES field to contents of the SPECIFIED
LOAD-UNLOAD COUNT OVER DEVICE LIFETIME field.
DS bit, SPF bit, PAGE CODE field, SUBPAGE CODE and PAGE LENGTH field
The DS bit, SPF bit, PAGE CODE field, SUBPAGE CODE and PAGE LENGTH field are described in 4.2.2.
DU bit, the TSD bit, the ETC bit, the TMC field, and the FORMAT AND LINKING field
The DU bit, the TSD bit, the ETC bit, the TMC field, and the FORMAT AND LINKING field for the Percentage Used Endurance Indicator log
parameter shall be set for a binary format list log parameter as described in 4.2.2.2.2.5.
4.2.15

Supported Log Pages log page (00h/ 00h)

The Supported Log Pages log page (see table 285) returns the list of log pages implemented by the logical unit. Logical units that
implement the LOG SENSE command shall implement this log page.
Table 285
Bit
Byte
0
1
2
3
4
...
n

Supported log pages
7

6

DS

SPF(1b)

5

(MSB)

4

3

2

1

0

PAGE CODE (00h)
SUBPAGE CODE (00h)
PAGE LENGTH (N-3)

(LSB)

SUPPORTED PAGE LIST

This log page is not defined for the LOG SELECT command. This log page returns the list of supported log pages for the specified logical
unit.
DS bit, SPF bit, PAGE CODE field and SUBPAGE CODE field
The DS bit, SPF bit, PAGE CODE field and SUBPAGE CODE field are described in 4.2.2.
PAGE LENGTH field
The PAGE LENGTH field indicates the length in bytes of the following supported log page list.
SUPPORTED PAGE LIST field
The SUPPORTED PAGE / SUBPAGE LIST field shall contain a list of all log page codes implemented by the logical unit in ascending order
beginning with page code 00h. Each supported log page is indicated in a one byte entry.

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4.2.16

Supported Log Pages and Subpages log page

For the LOG SENSE command, the Supported Log Pages and Subpages log page (see table 286) returns the list of log pages and subpages implemented by the logical unit. If log subpages are supported this page shall be supported. This log page is not defined for the
LOG SELECT command.
Table 286
Bit
Byte
0
1
2
3

Supported Log Pages and Subpages log page (00h/ FFh)
7

6

5

DS

SPF (1b)

4

3

2

1

0

PAGE CODE (00h)
SUBPAGE CODE (FFh)

(MSB)

PAGE LENGTH (n - 3)

(LSB)

SUPPORTED PAGE/SUBPAGE DESCRIPTORS
4
5
...
n-1
n

FIRST SUPPORTED PAGE/SUBPAGE DESCRIPTOR (see table 287)
...
LAST SUPPORTED PAGE/SUBPAGE DESCRIPTOR (see table 287)

DS bit, SPF bit, PAGE CODE field, SUBPAGE CODE field, and PAGE LENGTH field
The DS bit, SPF bit, PAGE CODE field, SUBPAGE CODE field, and PAGE LENGTH field are described in 4.2.2. The DS bit, SPF bit,
PAGE CODE field, and SUBPAGE CODE field shall be set as shown in table 286 for the Supported Log Pages and Subpages log page.
The supported page/subpage descriptors (see table 287) shall be in ascending order sorted by page code then subpage code and shall
include a descriptor with subpage code 00h for any implemented log page in which the SPF bit is set to zero.
Table 287
Bit
Byte
0
1

Supported page/subpage descriptor
7

6

5

Reserved

4

3

2

1

0

PAGE CODE
SUBPAGE CODE

PAGE CODE field
The PAGE CODE field indicates the number of a supported log page.
SUBPAGE CODE field
The SUBPAGE CODE field indicates the subpage number of a supported log page.

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4.2.17

Temperature log page (0Dh)

4.2.17.1

Overview

The Temperature log page (page code 0Dh) provides information about the current operating temperature of the SCSI Target Device using
the parameter codes listed in table 288.
Table 288

Temperature log page parameter codes

Parameter code

Description

Resettable or
Changeable [a]

Support
Required

0000h

Temperature

Never

Mandatory

0001h

Reference Temperature

Never

Optional

All others

Reserved

[a] The keywords in this column – Always, Reset Only, and Never – are defined in 4.2.2.3.
The Temperature log page has the format shown in table 289.
Table 289
Bit
Byte
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15

Temperature log page
7

6

DS

SPF (0)

5

4

3

2

1

PAGE CODE (0Dh)
SUBPAGE CODE (00h)

(MSB)

PAGE LENGTH (0Ch)

(MSB)

0

(LSB)

PARAMETER CODE 0000H TEMPERATURE

(LSB)

PARAMETER CONTROL BYTE – binary format list log parameter (see 4.2.2.2.2.5)
DU

Obsolete

TSD

ETC

TMC

FORMAT AND LINKING

PARAMETER LENGTH (02h)
Reserved
TEMPERATURE (DEGREES CELSIUS)
(MSB)

PARAMETER CODE 0001H REFERENCE TEMPERATURE

(LSB)

PARAMETER CONTROL BYTE – binary format list log parameter (see 4.2.2.2.2.5)
DU

Obsolete

TSD

ETC

TMC

FORMAT AND LINKING

PARAMETER LENGTH (02h)
Reserved
REFERENCE TEMPERATURE (DEGREES CELSIUS)

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DS bit, SPF bit, PAGE CODE field, SUBPAGE CODE field, and PAGE LENGTH field
The DS bit, SPF bit, PAGE CODE field, SUBPAGE CODE field, and PAGE LENGTH field are described in 4.2.2. The SPF bit, PAGE
CODE field, and SUBPAGE CODE field shall be set as shown in table 289 for the Temperature log page.
PARAMETER CODE field
The PARAMETER CODE field is described in 7.3.2.2.1, and shall be set as shown in table 430 for the Temperature log parameter.
DU bit, TSD bit, ETC bit, TMC field, and FORMAT AND LINKING field
The DU bit, TSD bit, ETC bit, TMC field, and FORMAT AND LINKING field are described in 4.2.2.2.2. These fields shall be set as
described for a binary format list log parameter (see 4.2.2.2.2.5) for the Temperature log parameter.
PARAMETER LENGTH field
The PARAMETER LENGTH field is described in 4.2.2.2.2, and shall be set as shown in table 289 for the Temperature log parameter.
TEMPERATURE field
The TEMPERATURE field indicates the temperature of the SCSI target device in degrees Celsius at the time the LOG SENSE command
is performed. Temperatures equal to or less than zero degrees Celsius shall cause the TEMPERATURE field to be set to zero. If the device
server is unable to detect a valid temperature because of a sensor failure or other condition, then the TEMPERATURE field shall be set to
FFh. The temperature should be reported with an accuracy of plus or minus three Celsius degrees while the SCSI target device is operating at a steady state within its environmental limits.
No comparison is performed between the contents of the TEMPERATURE field and the contents of the optional REFERENCE TEMPERATURE field.
REFERENCE TEMPERATURE field
The REFERENCE TEMPERATURE field indicates the maximum reported sensor temperature in degrees Celsius at which the SCSI target
device is capable of operating continuously without degrading the SCSI target device's operation or reliability beyond manufacturer
accepted limits. If the device server is unable to return a reference temperature and the optional Reference Temperature log parameter is
included in the Temperature log page being returned, then REFERENCE TEMPERATURE field is set to FFh.
The reference temperature may change for vendor specific reasons.

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4.3

Mode parameters

4.3.1

Mode parameters overview

This subclause describes the mode parameter headers, block descriptors, and mode pages used with MODE SELECT command (see
3.12 and 3.13) and MODE SENSE command (see 3.14 and 3.15) that are applicable to all SCSI devices. Subpages are identical to mode
pages except that they include a SUBPAGE CODE field that further differentiates the mode page contents. Mode pages specific to each
device type are described in the command standard that applies to that device type.
Note.

Many of the mode parameters in the following pages are changeable. A MODE SENSE command with the PC bit set to one
will return a mask indicating the mode parameters that may be changed by a SCSI initiator port. Seagate disk drive product
manuals indicate which pages a drive supports, what the default mode values are, and what mode parameters may be
changed.

Table 290 defines the mode pages that are applicable to all device types that implement the MODE SELECT and MODE SENSE
commands.
Table 290

Mode page codes and subpage codes

Page code

Subpage code

Mode Page Name

0Ah

02h

Application Tag

4.3.6

1Ch

01h

Background Control

4.3.7

08h

00h

Caching

4.3.8

0Ah

00h

Control

4.3.9

0Ah

01h

Control Extension

4.3.10

02h

00h

Disconnect-Reconnect

4.3.11

03h

00h

Format Device mode page (Obsolete)

4.3.12

1Ch

00h

Informational Exceptions Control

4.3.13

0Ch

00h

Notch (Obsolete)

09h

00h

Obsolete

1Ah

00h

Power Condition

4.3.14

1Ah

01h

Power Consumption

4.3.15

18h

00h

Protocol Specific LUN

4.3.17

19h

00h

Protocol Specific Port

4.3.18

01h

00h

Read-Write Recovery

4.3.16

04h

00h

Rigid Drive Geometry Parameters page (Obsolete)

4.3.19

07h

00h

Verify Recovery

4.3.21

18h

01h - FEh

(See specific SCSI transport protocol)

19h

01h - FEh

(See specific SCSI transport protocol)

00h

not applicable

3Fh

00h

Return all pages [a]

3Fh

FFh

Return all pages and subpages [a]

00h - 3Eh

FFh

Return all subpages [a]

Seagate specific Unit Attention parameters

Reference

4.3.20

All page code and subpage code combinations not shown in this table are reserved.
[a]

Valid only for the MODE SENSE command

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4.3.2

Mode parameter list format

The mode parameter list shown in table 291 contains a header, followed by zero or more block descriptors, followed by zero or more
variable-length mode pages. Parameter lists are defined for each device type.
Table 291
Bit
Byte

Mode parameter list
7

6

5

4

3

2

1

0

MODE PARAMETER HEADER
BLOCK DESCRIPTOR(S)
MODE PAGE(S) OR VENDOR SPECIFIC (E.G., PAGE CODE SET TO ZERO)
4.3.3

Mode parameter header formats

The mode parameter header that is used by the MODE SELECT(6) command (see 3.9) and the MODE SENSE(6) command (see 3.11) is
defined in table 292.
Table 292
Bit
Byte
0
1
2
3

Mode parameter header(6)
7

6

WP

5

4

3

2

MODE DATA LENGTH
MEDIUM TYPE
DPOFUA
BLOCK DESCRIPTOR LENGTH

Reserved

1

0

Reserved

The mode parameter header that is used by the MODE SELECT(10) command (see 3.10) and the MODE SENSE(10) command (see
3.12) is defined in table 293.
Table 293
Bit
Byte
0
1
2
3
4
5
6
7

Mode parameter header(10)
7

6

5

(MSB)

WP

4

3

2

1

MODE DATA LENGTH

Reserved

(MSB)

MEDIUM TYPE
DPOFUA
Reserved
Reserved
BLOCK DESCRIPTOR LENGTH

0

(LSB)
Reserved
LONGLBA

(LSB)

MODE DATA LENGTH field
When using the MODE SENSE command, the MODE DATA LENGTH field indicates the length in bytes of the following data that is available to be transferred. The mode data length does not include the number of bytes in the MODE DATA LENGTH field. When using the
MODE SELECT command, this field is reserved.
Note.

Logical units that support more than 256 bytes of block descriptors and mode pages may need to implement ten-byte mode
commands. The mode data length field in the six-byte CDB header limits the returned data to 256 bytes.

MEDIUM TYPE field
The contents of the MEDIUM TYPE field are unique for each device type. Refer to the mode parameters subclause of the specific device
type command standard for definition of these values. Some device types reserve this field.
WP (Write Protect) bit
1

A WP bit set to one indicates that the medium is write-protected. The medium may be write protected when the software write protect (SWP) bit in the Control mode page (see 4.3.9) is set to one or if another vendor specific mechanism causes the medium to be
write protected.

0

A WP bit set to zero indicates that the medium is not write-protected.

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DPOFUA (DPO and FUA support) bit
0

A DPOFUA bit set to zero indicates that the device server does not support the DPO and FUA bits.

1

When used with the MODE SENSE command, a DPOFUA bit set to one indicates that the device server supports the DPO and
FUA bits (see 3.18)

LONGLBA (Long LBA) bit
0

If the Long LBA (LONGLBA) bit is set to zero, the mode parameter block descriptor(s), if any, are each eight bytes long.

1

If the LONGLBA bit is set to one, the mode parameter block descriptor(s), if any, are each sixteen bytes long.

BLOCK DESCRIPTOR LENGTH field
The BLOCK DESCRIPTOR LENGTH field contains the length in bytes of all the block descriptors. It is equal to the number of block
descriptors times eight if the LONGLBA bit is set to zero or times sixteen if the LONGLBA bit is set to one, and does not include mode
pages or vendor specific parameters (e.g., page code set to zero), if any, that may follow the last block descriptor. A block descriptor length
of zero indicates that no block descriptors are included in the mode parameter list. This condition shall not be considered an error.
4.3.4
4.3.4.1

Mode parameter block descriptors
Mode block descriptors overview

If the device server returns a mode parameter block descriptor, it shall return a short LBA mode parameter block descriptor (see 4.3.4.2) in
the mode parameter data in response to:
a) a MODE SENSE (6) command; or
b) a MODE SENSE (10) command with the LLBAA bit set to zero.
If the device server returns a mode parameter block descriptor and the number of logical blocks is greater than FFFFFFFFh, it may return
a long LBA mode parameter block descriptor (see 4.3.4.3) in the mode parameter data in response to a MODE SENSE (10) command with
the LLBAA bit set to one.
If the application client sends a mode parameter block descriptor in the mode parameter list, it shall send a short LBA mode parameter
block descriptor (see 4.3.4.2) for a MODE SELECT (6) command.
If the application client sends a mode parameter block descriptor in the mode parameter list, it may send a long LBA mode parameter block
descriptor (see 4.3.4.3) for a MODE SELECT (10) command.
Support for the mode parameter block descriptors is optional. The device server shall establish a unit attention condition with the additional
sense code of MODE PARAMETERS CHANGED (see SPC-4 and SAM-5) when the block descriptor values are changed.

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4.3.4.2

Short LBA mode parameter block descriptor

Table 294 defines the block descriptor for direct-access block devices used:
a. with the MODE SELECT (6) and MODE SENSE (6) commands, and
b. with the MODE SELECT (10) and MODE SENSE (10) commands when the LONGLBA bit is set to zero in the mode parameter header
(see 4.3.3))
Table 294

Short LBA mode parameter block descriptor

Bit
Byte

7

0

(MSB)

6

5

4

3

1

0

NUMBER OF BLOCKS

...

(LSB)

3
Reserved

4
5

2

(MSB)

...
7

LOGICAL BLOCK LENGTH
(LSB)

A device server shall respond to a MODE SENSE command (see 3.12) by reporting the number of logical blocks specified in the NUMBER
OF LOGICAL BLOCKS field sent in the last MODE SELECT command that contained a mode parameter block descriptor. If no MODE
SELECT command with a mode parameter block descriptor has been received then the current number of logical blocks shall be returned.
To determine the number of logical blocks at which the logical unit is currently formatted, the application client shall use the READ
CAPACITY command (see 3.22) rather than the MODE SENSE command.
On a MODE SENSE command, the device server may return a value of zero indicating that it does not report the number of logical blocks
in the short LBA mode parameter block descriptor.
On a MODE SENSE command, if the number of logical blocks on the medium exceeds the maximum value that is able to be specified in
the NUMBER OF LOGICAL BLOCKS field, the device server shall return a value of FFFFFFFh.
If the logical unit does not support changing its capacity by changing the NUMBER OF LOGICAL BLOCKS field using the MODE SELECT
command (see 3.9 and 3.10), the value in the NUMBER OF LOGICAL BLOCKS field is ignored.
If the device supports changing its capacity by changing the NUMBER OF LOGICAL BLOCKS field, then the NUMBER OF LOGICAL
BLOCKS field is interpreted as follows:
a. If the NUMBER OF LOGICAL BLOCKS field is set to zero, the logical unit shall retain its current capacity if the logical block length has
not changed. If the NUMBER OF LOGICAL BLOCKS field is set to zero and the content of the LOGICAL BLOCK LENGTH field (i.e.,
new logical block length) is different than the current logical block length, the logical unit shall be set to its maximum capacity when the
new logical block length takes effect (i.e., after a successful FORMAT UNIT command);
b. If the NUMBER OF LOGICAL BLOCKS field is greater than zero and less than or equal to its maximum capacity, the logical unit shall
be set to that number of logical blocks. If the content of the LOGICAL BLOCK LENGTH field is the same as the current logical block
length, the logical unit shall not become format corrupt. This capacity setting shall be retained through power cycles, hard resets, logical unit resets, and I_T nexus losses. If the content of the LOGICAL BLOCK LENGTH field is the same as the current logical block
length this capacity setting shall take effect on successful completion of the MODE SELECT command. If the content of the LOGICAL
BLOCK LENGTH field (i.e., new logical block length) is different than the current logical block length this capacity setting shall take
effect when the new logical block length takes effect (i.e., after a successful FORMAT UNIT command);
c. If the NUMBER OF LOGICAL BLOCKS field is set to a value greater than the maximum capacity of the device and less than
FFFFFFFFh, then the MODE SELECT command shall be terminated with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN PARAMETER LIST. The logical unit shall retain its previous
logical block descriptor settings; or
d. If the NUMBER OF LOGICAL BLOCKS field is set to FFFFFFFFh, the logical unit shall be set to its maximum capacity. If the content of
the LOGICAL BLOCK LENGTH field is the same as the current logical block length, the logical unit shall not become format corrupt.
This capacity setting shall be retained through power cycles, hard resets, logical unit resets, and I_T nexus losses. If the content of the
LOGICAL BLOCK LENGTH field is the same as the current logical block length this capacity setting shall take effect of successful completion of the MODE SELECT command. If the content of the LOGICAL BLOCK LENGTH field (i.e., new logical block length) is different than the current logical block length this capacity setting shall take effect when the new logical block length takes effect (i.e., after a
successful FORMAT UNIT command).

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LOGICAL BLOCK LENGTH field
The LOGICAL BLOCK LENGTH field specifies the length in bytes of each logical block. No change shall be made to any logical blocks on
the medium until a format operation is initiated by an application client.
A device server shall respond to a MODE SENSE command (see 3.11 and 3.12) by reporting the length of the logical blocks as specified
in the LOGICAL BLOCK LENGTH field sent in the last MODE SELECT command that contained a mode parameter block descriptor. If no
MODE SELECT command with a block descriptor has been received then the current logical block length shall be returned (e.g., if the
logical block length is 512 bytes and a MODE SELECT command occurs with the LOGICAL BLOCK LENGTH field set to 520 bytes, any
MODE SENSE commands would return 520 in the LOGICAL BLOCK LENGTH field). To determine the logical block length at which the
logical unit is currently formatted, the application client shall use the READ CAPACITY command rather than the MODE SELECT
command.
4.3.4.3

Long LBA mode parameter block descriptor

Table 295 defines the block descriptor for direct-access block devices used with the MODE SELECT (10) command and MODE SENSE
(10) command when the LONGLBA bit is set to one in the mode parameter header (see 4.3.3).
Table 295

Long LBA mode parameter block descriptor

Bit
Byte

7

0

(MSB)

6

5

3

2

1

0

NUMBER OF LOGICAL BLOCKS

...
7
8
...
11
12

4

(LSB)
Reserved
(MSB)

...
15

LOGICAL BLOCK LENGTH
(LSB)

A device server shall respond to a MODE SENSE command (see 3.11 and 3.12) by reporting the number of logical blocks specified in the
NUMBER OF LOGICAL BLOCKS field sent in the last MODE SELECT command that contained a mode parameter block descriptor. If no
MODE SELECT command with a mode parameter block descriptor has been received then the current number of logical blocks shall be
returned. To determine the number of logical blocks at which the logical unit is currently formatted, the application client shall use the
READ CAPACITY command rather than the MODE SENSE command.
On a MODE SENSE command, the device server may return a value of zero indicating that it does not report the number of logical blocks
in the long LBA mode parameter block descriptor.
If the logical unit does not support changing its capacity by changing the NUMBER OF LOGICAL BLOCKS field using the MODE SELECT
command (see 3.10), the value in the NUMBER OF LOGICAL BLOCKS field is ignored. If the device supports changing its capacity by
changing the NUMBER OF LOGICAL BLOCKS field, then the NUMBER OF LOGICAL BLOCKS field is interpreted as follows:
a. If the NUMBER OF LOGICAL BLOCKS field is set to zero, the logical unit shall retain its current capacity if the logical block length has
not changed. If the NUMBER OF LOGICAL BLOCKS field is set to zero and the content of the LOGICAL BLOCK LENGTH field (i.e.,
new logical block length) is different than the current logical block length, the logical unit shall be set to its maximum capacity when the
new logical block length takes effect (i.e., after a successful FORMAT UNIT command).
b. If the NUMBER OF LOGICAL BLOCKS field is greater than zero and less than or equal to its maximum capacity, the logical unit shall
be set to that number of logical blocks. If the content of the LOGICAL BLOCK LENGTH field is the same as the current logical block
length, the logical unit shall not become format corrupt. This capacity setting shall be retained through power cycles, hard resets, logical unit resets, and I_T nexus losses. If the content of the LOGICAL BLOCK LENGTH field is the same as the current logical block
length this capacity setting shall take effect on successful completion of the MODE SELECT command. If the content of the LOGICAL
BLOCK LENGTH field (i.e., new logical block length) is different than the current logical block length, this capacity setting shall take
effect when the new logical block length takes effect (i.e., after a successful FORMAT UNIT command);
c. If the NUMBER OF LOGICAL BLOCKS field is set to a value greater than the maximum capacity of the device and less than
FFFFFFFF FFFFFFFFh, then the device server shall terminate the MODE SELECT command with CHECK CONDITION status with
the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN PARAMETER LIST. The logical unit
shall retain its previous block descriptor settings; or

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d. If the NUMBER OF LOGICAL BLOCKS field is set to FFFFFFFF FFFFFFFFh, the logical unit shall be set to its maximum capacity. If
the content of the LOGICAL BLOCK LENGTH field is the same as the current logical block length, the logical unit shall not become format corrupt. This capacity setting shall be retained through power cycles, hard resets, logical unit resets, and I_T nexus losses. If the
content of the LOGICAL BLOCK LENGTH field is the same as the current logical block length this capacity setting shall take effect on
successful completion of the MODE SELECT command. If the content of the LOGICAL BLOCK LENGTH field (i.e., new logical block
length) is different than the current logical block length this capacity setting shall take effect when the new logical block length takes
effect (i.e., after a successful FORMAT UNIT command).
The LOGICAL BLOCK LENGTH field specifies the length in bytes of each logical block. No change shall be made to any logical blocks on
the medium until a format operation is initiated by an application client.
A device server shall respond to a MODE SENSE command (see 3.11 and 3.12) by reporting the length of the logical blocks as specified
in the LOGICAL BLOCK LENGTH field sent in the last MODE SELECT command that contained a mode parameter block descriptor. If no
MODE SELECT command with a block descriptor has been received then the current logical block length shall be returned (e.g., if the
logical block length is 512 bytes and a MODE SELECT command occurs with the LOGICAL BLOCK LENGTH field set to 520 bytes, any
MODE SENSE command would return 520 in the LOGICAL BLOCK LENGTH field). To determine the logical block length at which the
logical unit is currently formatted, the application client shall use the READ CAPACITY command rather than the MODE SELECT
command.
4.3.5

Mode page and subpage formats and page codes

The page_0 mode page format is defined in table 296.
Table 296
Bit
Byte
0

Page_0 mode page format
7

6

PS

SPF (0b)

5

4

3

2

1

0

1

0

PAGE CODE
PAGE LENGTH (N-1)

1
2
...
n

MODE PARAMETERS

The SUB_PAGE mode page format is defined in table 297.
Table 297
Bit
Byte
0
1
2
3
4

SUB_PAGE mode page format
7

6

PS

SPF (1b)

5

(MSB)

4

3

2

PAGE CODE
SUBPAGE CODE
PAGE LENGTH (N-3)

(LSB)

MODE PARAMETERS

...
n

Each mode page contains a PS bit, an SPF bit, a PAGE CODE field, a PAGE LENGTH field, and a set of mode parameters. The page
codes are defined in this subclause and in the mode parameter subclauses in the command standard for the specific device type. Each
mode page with a SPF bit set to one contains a SUBPAGE CODE field.
PS (parameters saveable) bit
1

When using the MODE SENSE command, a parameters saveable (PS) bit set to one indicates that the mode page may be saved
by the logical unit in a nonvolatile, vendor specific location.

0

A PS bit set to zero indicates that the device server is not able to save the supported parameters. When using the MODE SELECT
command, the PS bit is reserved.

SPF (SubPage Format) bit
0

A SubPage Format (SPF) bit set to zero indicates that the page_0 mode page format is being used.

1

A SPF bit set to one indicates that the SUB_PAGE mode page format is being used.

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PAGE CODE and SUBPAGE CODE fields
The PAGE CODE and SUBPAGE CODE fields identify the format and parameters defined for that mode page. Some page codes are
defined as applying to all device types and other page codes are defined for the specific device type. The page codes that apply to a specific device type are defined in the command standard for that device type. The applicability of each subpage code matches that of the
page code with which it is associated.
When using the MODE SENSE command, if page code 00h (vendor specific mode page) is implemented, the device server shall return
that mode page last in response to a request to return all mode pages (page code 3Fh). When using the MODE SELECT command, this
mode page should be sent last.
PAGE LENGTH field
The PAGE LENGTH field specifies the length in bytes of the mode parameters that follow. If the application client does not set this value to
the value that is returned for the mode page by the MODE SENSE command, the command shall be terminated with CHECK CONDITION
status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN PARAMETER LIST. The
logical unit may implement a mode page that is less than the full mode page length defined, provided no field is truncated and the PAGE
LENGTH field correctly specifies the actual length implemented.
MODE PARAMETERS
The MODE PARAMETERS for each mode page are defined in the following subclauses, or in the mode parameters subclause in the command standard for the specific device type. MODE PARAMETERS not implemented by the logical unit shall be set to zero.
4.3.6

Application Tag mode page (0Ah/ 02h)

The Application Tag mode page (see table 298) specifies the Application Tag that a device server configured for protection information (see
4.22.2) shall use for each LBA range if the ATO bit in the Control mode page (see 4.3.9) is set to one. The mode page policy (see 4.4.12)
for this page shall be shared.
If a method not defined by this standard changes the parameter data to be returned by the device server in the Application Tag mode page,
then the device server shall establish a unit attention condition for the initiator port associated with every I_T nexus with the additional
sense code set to MODE PARAMETERS CHANGED.
Table 298
Bit
Byte
0
1
2
3
4
...
15

Application Tag mode page
7

6

PS

SPF (1b)

5

(MSB)

4

3

2

1

0

PAGE CODE (0Ah)
SUBPAGE CODE(02h)
PAGE LENGTH (n - 3)

(LSB)

(MSB)
Reserved
(LSB)
Application Tag Descriptors

16
...
39
...
n - 24
...
n

Application Tag descriptor (first)
...
Application Tag descriptor (last)

The parameters saveable (PS) bit, the subpage format (SPF) bit, the PAGE CODE field, the SUBPAGE CODE field, and the PAGE
LENGTH field are defined in SPC-4.
The SPF bit, the PAGE CODE field, the SUBPAGE CODE field, and the PAGE LENGTH field shall be set to the values shown in Table 298.

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4.3.6.1

Application Tag descriptor

The application tag descriptor format is decsribed in Table 299.
Table 299
Bit
Byte
0
1
...
5
6
7
8
...
15
16
...

Application Tag descriptor format
7

6

LAST

5

4

3

2

1

0

Reserved
Reserved

(MSB)

LOGICAL BLOCK APPLICATION TAG

(LSB)

(MSB)
LOGICAL BLOCK ADDRESS
(LSB)
(MSB)
LOGICAL BLOCK COUNT

23

(LSB)

LAST bit
1

A LAST bit set to one specifies that this Application Tag descriptor is the last valid Application Tag descriptor in the Application Tag
mode page.

0

A LAST bit set to zero specifies that the Application Tag descriptor is not the last valid Application Tag descriptor in the Application
Tag mode page.

LOGICAL BLOCK APPLICATION TAG field
The LOGICAL BLOCK APPLICATION TAG field specifies the value to be compared with the LOGICAL BLOCK APPLICATION TAG field
associated with data read or written to the LBA.
LOGICAL BLOCK ADDRESS field
The LOGICAL BLOCK ADDRESS field contains the starting LBA for this Application Tag descriptor. The LOGICAL BLOCK ADDRESS field
in the first Application Tag descriptor shall be set to 0000_0000_0000_0000h. For subsequent Application Tag descriptors, the contents of
the LOGICAL BLOCK ADDRESS field shall contain the sum of the values in:
a. the LOGICAL BLOCK ADDRESS field in the previous Application Tag descriptor; and
b. the LOGICAL BLOCK COUNT field in the previous Application Tag descriptor.
The sum of the LOGICAL BLOCK ADDRESS field in the Application Tag descriptor with the LAST bit set to one and the LOGICAL BLOCK
COUNT field in the Application Tag descriptor with the LAST bit set to one shall equal the RETURNED LOGICAL BLOCK ADDRESS field
in the READ CAPACITY (16) parameter data (see 3.24.2).
If an invalid combination of the LAST bit, LOGICAL BLOCK APPLICATION TAG field, and LOGICAL BLOCK ADDRESS field are sent by
the application client, then the device server shall terminate the MODE SELECT command (see 3.10) with CHECK CONDITION status
with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN PARAMETER LIST. The LOGICAL
BLOCK COUNT field specifies the number of logical blocks to which this Application Tag descriptor applies.
LOGICAL BLOCK COUNT field
A LOGICAL BLOCK COUNT field set to 0000_0000_0000_0000h specifies that this Application Tag descriptor shall be ignored.

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4.3.7

Background Control mode page (1Ch/ 01h)

The Background Control mode page (see table 300) is a subpage of the Informational Exception Control mode page (see 4.3.13) and
provides controls over background operations. The mode page policy (see 4.4.12) for this subpage shall be shared.
Table 300

Background Control mode page

Bit
Byte

7

6

0

PS

SPF(1b)

5

4

3

2

1

0

PAGE CODE (1Ch)
SUBPAGE CODE (01h)

1
(MSB)

2

PAGE LENGTH

3
Reserved

4

(LSB)
S_L_FULL

Reserved

5
(MSB)

6
7

BACKGROUND MEDIUM SCAN INTERVAL TIME

(MSB)

8

BACKGROUND PRE-SCAN TIME LIMIT

9
(MSB)

10
11

(MSB)

12
13

MINIMUM IDLE TIME BEFORE BACKGROUND SCAN

MAXIMUM TIME TO SUSPEND BACKGROUND SCAN

14

LOWIR

EN_BMS
EN_PS

(LSB)

(LSB)

(LSB)

(LSB)

Reserved

15

PS bit, SPF bit, PAGE CODE field, SUBPAGE CODE field, and PAGE LENGTH field
The parameters saveable (PS) bit, the subpage format (SPF) bit, the PAGE CODE field, the SUBPAGE CODE field, and the PAGE
LENGTH field are defined in 4.3.5.
S_L_FULL bit
0

A suspend on log full (S_L_FULL) bit set to zero specifies that the device server shall continue running a background scan operation (see SPC-4) even if the Background Scan Results log page (see 4.2.4) contains the maximum number of Background Scan log
parameters (see table 253) supported by the logical unit.

1

A S_L_FULL bit set to one specifies that the device server shall suspend a background scan operation if the Background Scan
Results log page contains the maximum number of Background scan log parameters supported by the logical unit.

LOWIR bit
0

A log only when intervention required (LOWIR) bit set to zero specifies that the device server shall log all suspected recoverable
medium errors or unrecoverable medium errors that are identified during background scan operations in the Background Scan
Results log page.

1

A LOWIR bit set to one specifies that the device server shall only log medium errors identified during back ground scan operations
in the Background Scan Results log page that require application client intervention.

EN_BMS (Enable Background Medium Scan) bit
0

An enable background medium scan (EN_BMS) bit set to zero specifies that background medium scan is disabled.

1

An EN_BMS bit set to one specifies that background medium scan operations are enabled. If the EN_PS bit is also set to one then
a background medium scan operation shall not start until after the pre-scan operation is halted or completed.

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If a background medium scan operation is in progress when the EN_BMS bit is changed from one to zero, then the logical unit shall suspend the background medium scan operation before the device server completes the MODE SELECT command, and the background
medium scan shall remain suspended until the EN_BMS bit is set to one, at which time the background medium scan operation shall
resume, beginning with the logical block being tested when the background medium scan was suspended.
EN_PS (enable pre-scan) bit
0

An enable pre-scan (EN_PS) bit set to zero specifies that pre-scan is disabled. If a pre-scan operation is in progress when EN_PS
is changed from a one to a zero then pre-scan is halted.

1

An EN_PS bit set to one specifies that a pre-scan operation is started after the next power on cycle.

Once this pre-scan has completed, another pre-scan shall not occur unless the EN_PS bit is set to zero, then set to one, and another
power on cycle occurs.
BACKGROUND MEDIUM SCAN INTERVAL TIME field
The BACKGROUND MEDIUM SCAN INTERVAL TIME field specifies the minimum time, in hours, between the start of one pre-scan or
background medium scan operation and the start of the next background medium scan operation. If the current background medium scan
operation takes longer than the value specified in the BACKGROUND MEDIUM SCAN INTERVAL TIME field, then the logical unit shall:
a) continue the current background pre-scan operation or background medium scan operation until that background scan operation
is complete; and
b) the logical unit shall start the next background medium scan operation starts upon completion of the current background pre-scan
operation or background medium scan operation.
BACKGROUND PRE-SCAN TIME LIMIT field
The BACKGROUND PRE-SCAN TIME LIMIT field specifies the maximum time, in hours, for a background pre-scan operation to complete. If the background pre-scan operation does not complete within the specified time then the device server shall halt the background
pre-scan operation. A value of zero specifies an unlimited timeout value.
MINIMUM IDLETIME BEFORE BACKGROUND SCAN field
The MINIMUM IDLE TIME BEFORE BACKGROUND SCAN field specifies the time, in milliseconds, that the logical unit shall be idle after
suspending a background scan operation before resuming a background scan operation (e.g., after the device server has completed all of
the commands in the task set).
MAXIMUM TIME TO SUSPEND BACKGROUND SCAN field
The MAXIMUM TIME TO SUSPEND BACKGROUND SCAN field specifies the time, in milliseconds, that the device server should take to
start processing a command received while a logical unit is performing a background scan operation.

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4.3.8

Caching Mode page (08h)

The Caching Mode page for MODE SENSE/MODE SELECT defines the parameters that affect the use of the cache (see table 301).
Table 301

Caching Mode page (08h)

Bit
Byte

7

6

0

PS

SPF (0b)

5

4

IC

3

DEMAND READ RETENTION PRIORITY

ABPF

(MSB)

CAP

(MSB)
(MSB)
(MSB)
LBCSS

(MSB)

15

DRA

RCD

WRITE RETENTION PRIORITY

Vendor specific

(LSB)
(LSB)
(LSB)
(LSB)

SYNC_PROG

CACHE SEGMENT SIZE

NV_DIS

(LSB)

Reserved

16
17

MF

NUMBER OF CACHE SEGMENTS

13
14

WCE

MAXIMUM PREFETCH CEILING

11
FSW

SIZE

MAXIMUM PREFETCH

9

12

DISC

MINIMUM PREFETCH

7

10

0

DISABLE PREFETCH TRANSFER LENGTH

5

8

1

PAGE LENGTH (12h)

2

6

2

PAGE CODE (08h)

1

4

3

(MSB)

...

Obsolete

19

(LSB)

PS bit
The returned Parameter Savable (PS) bit of 1 indicates that page 08h parameter data is savable.
SPF bit, the PAGE CODE field and the PAGE LENGTH field
The SPF bit, the PAGE CODE field and the PAGE LENGTH field shall be set to the values shown in table 301 for the Caching mode page.
IC enable bit
1

When the Initiator Control (IC) enable bit is set to one, adaptive read look-ahead (ARLA) is disabled.

0

When IC is set to ZERO, ARLA is enabled. Since Seagate drives covered by this manual do not organize the cache according to
size of segment, but rather by number of segments, this bit is used to enable or disable ARLA (in non-Seagate equipment, this
might be used to designate cache size).

Note. ARLA cannot be disabled in some Seagate drives using the ASAII code. See individual drive’s Product Manual, Volume 1.
ABPF bit
1

The ABORT PREFETCH (ABPF) bit, when set to one, with the DRA bit equal to zero, requests that the SCSI device abort the
PREFETCH upon selection. The ABPF set to one takes precedence over the Minimum PREFETCH bytes.

0

When set to zero, with the DRA bit equal to zero, the termination of any active PREFETCH is dependent upon Caching Page bytes
4 through 11 and is operation and/or vendor-specific.

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CAP (Caching Analysis Permitted) bit
1

The Caching Analysis Permitted (CAP) bit, when set to one, enables caching analysis.

0

A zero indicates caching analysis is disabled. Caching analysis results are placed in the SCSI logging information table, (see Table
). See individual drive’s Product Manual, Volume 1, SCSI Bus Conditions and Miscellaneous Features Supported table.

DISC (Discontinuity) bit
1

The Discontinuity (DISC) bit, when set to one, requests that the SCSI device continue the PREFETCH across time discontinuities,
such as across cylinders or tracks up to the limits of the buffer, or segment, space available for PREFETCH.

0

When set to zero, the DISC requests that prefetches be truncated at time discontinuities.

SIZE (Size Enable) bit
1

The Size Enable (SIZE) bit, when set to one, indicates that the Cache Segment Size is to be used to control caching segmentation.

0

When SIZE equals zero, the Initiator requests that the Number of Cache Segments is to be used to control caching segmentation.
For Seagate drives covered by this manual, SIZE is always zero.

WCE (Write Cache Enable) bit
0

SCSI WRITE commands may not return status and completion message bytes until all data has been written to the media.

1

SCSI WRITE commands may return status and completion message bytes as soon as all data has been received from the host.

MF (Multiplication Factor) bit
0

The Minimum PREFETCH and Maximum PREFETCH fields are interpreted as a number of logical blocks.

1

Specifies that the target shall interpret the minimum and maximum PREFETCH fields to be specified in terms of a scalar number
which, when multiplied by the number of logical blocks to be transferred for the current command, yields the number of logical
blocks for each of the respective types of PREFETCH.

RCD (READ Cache Disable) bit
0

SCSI READ commands may access the cache or the media.

1

SCSI READ commands must access the media. Data cannot come from the cache.

DEMAND READ RETENTION PRIORITY field
DEMAND READ RETENTION PRIORITY. The cache replacement algorithm does not distinguish between retention in the cache of hostrequested data and PREFETCH data. Therefore, this half byte is always 0.
WRITE RETENTION PRIORITY field
WRITE RETENTION PRIORITY. The cache replacement algorithm does distinguish between retention in the cache of host-requested data
and PREFETCH data. Therefore, this half byte is always 0.
DISABLE PREFETCH TRANSFER LENGTH field
DISABLE PREFETCH TRANSFER LENGTH. PREFETCH is disabled for any SCSI READ command whose requested transfer length
exceeds this value.
MINIMUM PREFETCH field
The MINIMUM PREFETCH specifies the minimum number sectors to prefetch, regardless of the delay it may cause to other commands.
MAXIMUM PREFETCH field
The MAXIMUM PREFETCH specifies the maximum number of logical blocks that may be prefetched. The PREFETCH operation may be
aborted before the MAXIMUM PREFETCH value is reached, but only if the MINIMUM PREFETCH value has been satisfied.
MAXIMUM PREFETCH CEILING field
The MAXIMUM PREFETCH Ceiling specifies an upper limit on the number of logical blocks computed as the maximum prefetch. If the
MAXIMUM PREFETCH value is greater than the MAXIMUM PREFETCH CEILING, the value is truncated to the MAXIMUM PREFETCH
CEILING value.

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FSW (FORCE SEQUENTIAL WRITE) bit
1

The Force Sequential Write (FSW) bit, when set to one, indicates that multiple block writes are to be transferred over the SCSI bus
and written to the media in an ascending, sequential, logical block order.

0

When the FSW bit equals zero, the target is allowed to reorder the sequence of writing addressed logical blocks in order to achieve
a faster command completion.

LBCSS bit
1

A logical block cache segment size (LBCSS) bit set to one specifies that the CACHE SEGMENT SIZE field units shall be interpreted as logical blocks.

0

An LBCSS bit set to zero specifies that the CACHE SEGMENT SIZE field units shall be interpreted as bytes. The LBCSS shall not
impact the units of other fields.

DRA (Disable READ-Ahead) bit
1

The Disable READ-Ahead (DRA) bit, when set to one, requests that the target not read into the buffer any logical blocks beyond the
addressed logical block(s).

0

When the DRA bit equals zero, the target may continue to read logical blocks into the buffer beyond the addressed logical block(s).

SYNC_PROG field
The synchronize cache progress indication support (SYNC_PROG) field specifies device server progress indication reporting for the
SYNCHRONIZE CACHE commands as defined in 3.52.
NV_DIS bit
1

An NV_DIS bit set to one specifies that the device server shall disable a non-volatile cache and indicates that a non-volatile cache
is supported but disabled.

0

An NV_DIS bit set to zero specifies that the device server may use a non-volatile cache and indicates that a non-volatile cache may
be present and enabled.

NUMBER OF CACHE SEGMENTS byte
The NUMBER OF CACHE SEGMENTS byte gives the number of segments into which the host requests the drive divide the cache.
CACHE SEGMENT SIZE field
The CACHE SEGMENT SIZE field indicates the requested segment size in bytes. This manual assumes that the Cache Segment Size
field is valid only when the Size bit is one.
DPO (Disable Page Out) bit
0

A Disable Page Out (DPO) bit set to zero specifies that the retention priority shall be determined by the RETENTION PRIORITY
fields in the Caching mode page (see 4.3.8).

1

A DPO bit set to one specifies that the device server shall assign the logical blocks accessed by this command the lowest retention
priority for being fetched into or retained by the cache. A DPO bit set to one overrides any retention priority specified in the Caching
mode page. All other aspects of the algorithm implementing the cache replacement strategy are not defined by this manual.

Note.

The DPO bit is used to control replacement of logical blocks in the cache when the application client has information on the
future usage of the logical blocks. If the DPO bit is set to one, the application client is specifying that the logical blocks
accessed by the command are not likely to be accessed again in the near future and should not be put in the cache nor
retained by the cache. If the DPO bit is set to zero, the application client is specifying that the logical blocks accessed by this
command are likely to be accessed again in the near future.

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4.3.9

Control mode page (0Ah)

The Control mode page (see table 302) provides controls over SCSI features that are applicable to all device types (e.g., task set
management and error logging). If a field in this mode page is changed while there is a task already in the task set, it is vendor specific
whether the old or new value of the field applies to that task. The mode page policy (see 3.9) for this mode page shall be shared, or per I_T
nexus.
Table 302

Control mode page

Bit
Byte

7

6

0

PS

SPF (0b)

5

4

3

2

1

0

GLTSD

RLEC

PAGE CODE (0Ah)
PAGE LENGTH (0Ah)

1
TST

2

TMF_ONLY

QUEUE ALGORITHM MODIFIER

3
4

VS

RAC

5

ATO

TAS

6

(MSB)

UA_INTLCK_CTRL
ATMPE

(MSB)

(MSB)

11

NUAR
SWP

QERR
RAERP
Obsolete

Reserved

BUSY TIMEOUT PERIOD

9
10

D_SENSE

Obsolete formerly
READY AER HOLDOFF PERIOD

7
8

RWWP

DPICZ

EXTENDED SELF-TEST COMPLETION TIME

UAAERP
Obsolete

DQUE
Obsolete
EAERP
Obsolete

AUTOLOAD MODE

(LSB)

(LSB)

(LSB)

PS bit, SPF bit, PAGE CODE field, and PAGE LENGTH field
The PS bit, SPF bit, PAGE CODE field, and PAGE LENGTH field are described in 4.3.5.
TST (task set type) field
A task set type (TST) field specifies the type of task set in the logical unit (see table 303).
Table 303

Task set type (TST) field

Code

Description

000b

The logical unit maintains one task set for all I_T nexuses

001b

The logical unit maintains separate task sets for each I_T nexus

010b - 111b

Reserved

Regardless of the mode page policy (see 4.4.12) for the Control mode page, the shared mode page policy shall be applied to the TST field.
If the most recent MODE SELECT changes the setting of this field, then the device server shall establish a unit attention condition (see
SAM-5) for the initiator port associated with every I_T nexus except the I_T nexus on which the MODE SELECT command was received,
with the additional sense code set to MODE PARAMETERS CHANGED.
TMF_ONLY (Allow Task Management Functions Only) bit
0

The allow task management functions only (TMF_ONLY) bit set to zero specifies that the device server shall process tasks with the
ACA task attribute received on the faulted I_T nexus when an ACA condition has been established (see SAM-5).

1

A TMF_ONLY bit set to one specifies that the device server shall terminate all tasks received on the faulted I_T nexus with an ACA
ACTIVE status when an ACA condition has been established.

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DPICZ bit
0

A disable protection information check if protect field is zero (DPICZ) bit set to zero indicates that checking of protection information
bytes is enabled.

1

A DPICZ bit set to one indicates that checking of protection information is disabled on commands with:
a. the RDPROTECT field (see SBC-3) set to zero;
b. the VRPROTECT field (see SBC-3) set to zero; or
c. the ORPROTECT field (see SBC-3) set to zero.

D_SENSE (DESCRIPTOR FORMAT SENSE DATA) bit
0

A descriptor format sense data (D_SENSE) bit set to zero specifies that the device server shall return the fixed format sense data
when returning sense data in the same I_T_L_Q nexus transaction as a CHECK CONDITION status.

1

A D_SENSE bit set to one specifies that the device server shall return descriptor format sense data when returning sense data in
the same I_T_L_Q nexus transaction as a CHECK CONDITION status, except as defined in 2.4.1.

GLTSD (Global Logging Target Save Disable) bit
0

A global logging target save disable (GLTSD) bit set to zero specifies that the logical unit implicitly saves, at vendor specific intervals, each log parameter in which the TSD bit (see 4.2) is set to zero.

1

A GLTSD bit set to one specifies that the logical unit shall not implicitly save any log parameters.

RLEC (Report Log Exception Condition) bit
1

A report log exception condition (RLEC) bit set to one specifies that the device server shall report log exception conditions as
described in 4.2.2.

0

A RLEC bit set to zero specifies that the device server shall not report log exception conditions.

QUEUE ALGORITHM MODIFIER field
The QUEUE ALGORITHM MODIFIER field (see table 304) specifies restrictions on the algorithm used for reordering tasks having the SIMPLE task attribute (see SAM-5).
Table 304

QUEUE ALGORITHM MODIFIER field

Code

Description

0h

Restricted reordering

1h

Unrestricted reordering allowed

2h - 7h

Reserved

8h - Fh

Vendor specific

A value of zero in the QUEUE ALGORITHM MODIFIER field specifies that the device server shall order the processing sequence of tasks
having the SIMPLE task attribute such that data integrity is maintained for that I_T nexus (i.e., if the transmission of new SCSI transport
protocol requests is halted at any time, the final value of all data observable on the medium shall have exactly the same value as it would
have if all the tasks had been given the ORDERED task attribute).
A value of one in the QUEUE ALGORITHM MODIFIER field specifies that the device server may reorder the processing sequence of tasks
having the SIMPLE task attribute in any manner. Any data integrity exposures related to task sequence order shall be explicitly handled by
the application client through the selection of appropriate commands and task attributes.
NUAR bit
1

A no unit attention on release (NUAR) bit set to one specifies that the device server shall not establish a unit attention condition as
described in 5.13.11.2.2.

0

A NUAR bit set to zero specifies that the device server shall establish a unit attention condition as described in SPC-4.

QERR (queue error management) field
The queue error management (QERR) field (see table 305) specifies how the device server shall handle other tasks when one task is terminated with CHECK CONDITION status (see SAM-5). The task set type (see the TST field definition in this subclause) defines which
other tasks are affected. If the TST field equals 000b, then all tasks from all I_T nexuses are affected. If the TST field equals 001b, then
only tasks from the same I_T nexus as the task that is terminated with CHECK CONDITION status are affected.

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Table 305

Queue error management (QERR) field

Code

Definition

00b

If an ACA condition is established, the affected tasks in the task set shall resume after the ACA condition is
cleared (see SAM-5). Otherwise, all tasks other than the task that received the CHECK CONDITION status
shall be processed as if no error occurred.

01b

All the affected tasks in the task set shall be aborted when the CHECK CONDITION status is sent. If the
TAS bit is set to zero, a unit attention condition (see SAM-5) shall be established for the initiator port associated with every I_T nexus that had tasks aborted except for the I_T nexus on which the CHECK CONDITION status was returned, with the additional sense code set to COMMANDS CLEARED BY ANOTHER
INITIATOR. If the TAS bit is set to one, all affected tasks in the task set for I_T nexuses other than the I_T
nexus for which the CHECK CONDITION status was sent shall be completed with a TASK ABORTED status and no unit attention shall be established. For the I_T nexus to which the CHECK CONDITION status is
sent, no status shall be sent for the tasks that are aborted.

10b

Reserved

11b

Affected tasks in the task set belonging to the I_T nexus on which a CHECK CONDITION status is
returned shall be aborted when the status is sent.

DQUE (Disable Queuing) bit
A Disable Queuing (DQUE) bit of one indicates that tagged queuing is disabled on the drive. Any pending commands in the queue for that
I_T_X nexus is aborted. Any subsequent queue tag message received shall be rejected with a MESSAGE REJECT message and the I/O
process shall be executed as an untagged command. A DQUE bit of zero indicates that tagged queuing is enabled, if the drive supports
tagged Queuing.
The DQUE bit has been declared obsolete by the T10 committee and is not supported.

Note.
VS bit
0

The VENDOR SPECIFIC (VS) bit is not supported in Seagate products.

RAC (report a check) bit
1

The report a check (RAC) bit provides control of reporting long busy conditions or CHECK CONDITION status. A RAC bit set to one
specifies that the device server should return CHECK CONDITION status rather than returning BUSY status if the reason for
returning the BUSY status may persist for a longer time than that specified by the AUTOLOAD MODE field.

0

A RAC bit set to zero specifies that the device server may return BUSY status regardless of the length of time the reason for returning BUSY status may persist.

UA_INTLCK_CTRL (unit attention interlocks control) field
The unit attention interlocks control (UA_INTLCK_CTRL) field (see table 306) controls the clearing of unit attention conditions reported in
the same I_T_L_Q nexus transaction as a CHECK CONDITION status and whether returning a status of BUSY, TASK SET FULL or RESERVATION CONFLICT results in the establishment of a unit attention condition (see SAM-5).
Table 306

Unit attention interlocks control (UA_INTLCK_CTRL) field

Code

Definition

00b

The logical unit shall clear any unit attention condition reported in the same I_T_L_Q nexus transaction as a CHECK
CONDITION status and shall not establish a unit attention condition when a task is terminated with BUSY, TASK SET
FULL, or RESERVATION CONFLICT status.

01b

Reserved [a]

10b [a]

The logical unit shall not clear any unit attention condition reported in the same I_T_L_Q nexus transaction as a CHECK
CONDITION status and shall not establish a unit attention condition when a task is terminated with BUSY, TASK SET
FULL, or RESERVATION CONFLICT status.

The logical unit shall not clear any unit attention condition reported in the same I_T_L_Q nexus transaction as a CHECK
CONDITION status and shall establish a unit attention condition for the initiator port associated with the I_T nexus on
which the BUSY, TASK SET FULL, or RESERVATION CONFLICT status is being returned. Depending on the status, the
11b [a]
additional sense code shall be set to PREVIOUS BUSY STATUS, PREVIOUS TASK SET FULL STATUS, or PREVIOUS
RESERVATION CONFLICT STATUS. Until it is cleared by a REQUEST SENSE command, a unit attention condition shall
be established only once for a BUSY, TASK SET FULL, or RESERVATION CONFLICT status regardless to the number of
commands terminated with one of those status values.
[a] A REQUEST SENSE command still clears any unit attention condition that it reports.

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SWP (Software Write Protect) bit
1

A software write protect (SWP) bit set to one specifies that the logical unit shall inhibit writing to the medium after writing all cached
or buffered write data, if any. When SWP is one, all commands requiring writes to the medium shall be terminated with CHECK
CONDITION status, with the sense key set to DATA PROTECT, and the additional sense code set to WRITE PROTECTED. When
SWP is one and the device type's command standard defines a write protect (WP) bit in the DEVICE-SPECIFIC PARAMETER field
in the mode parameter header, the WP bit shall be set to one for subsequent MODE SENSE commands.

0

A SWP bit set to zero specifies that the logical unit may allow writing to the medium, depending on other write inhibit mechanisms
implemented by the logical unit. When the SWP bit is set to zero, the value of the WP bit, if defined, is device type specific. For a list
of commands affected by the SWP bit and details of the WP bit see the command standard for the specific device type.

The RAERP, UAAERP, and EAERP bits enable specific events to be reported via the asynchronous event reporting protocol. When all
three bits are zero, the target shall not use asynchronous event reporting. AER is defined in SAM-2.
These three bits have been declared obsolete by the T10 committee and are not supported.

Note.

RAERP (Ready AER Permission) bit (obsolete)
1

A Ready AER Permission (RAERP) bit of one specifies that the target may issue an asynchronous event report upon completing its
initialization sequence instead of generating a unit attention condition.

0

A RAERP bit of zero specifies that the target shall not issue an asynchronous event report upon completing its initialization
sequence.

UAAERP (UNIT ATTENTION AER Permission) bit (obsolete)
1

A UNIT ATTENTION AER Permission (UAAERP) bit of one specifies that the target may issue an asynchronous event report
instead of creating a unit attention condition upon detecting an unit attention condition event (other than upon completing an initialization sequence).

0

A UAAERP bit of zero specifies that the target shall not issue an asynchronous event reporting instead of creating a unit attention
condition.

EAERP (Error AER Permission) bit (obsolete)
1

An Error AER Permission (EAERP) bit of one specifies that the target may issue an asynchronous event report upon detecting a
deferred error condition instead of waiting to report the deferred error on the next command.

0

An EAERP bit of zero specifies that the target shall not report deferred error conditions via an asynchronous event reporting.

ATO (application tag owner) bit
1

An application tag owner (ATO) bit set to one specifies that the contents of the LOGICAL BLOCK APPLICATION TAG field in the
protection information, if any, shall not be modified by the device server.

0

An ATO bit set to zero specifies that the contents of the LOGICAL BLOCK APPLICATION TAG field in the protection information, if
any, may be modified by the device server. If the ATO bit is set to zero, the device server shall ignore the contents of the LOGICAL
BLOCK APPLICATION TAG field in the protection information when received from the application client.

TAS (Task Aborted Status) bit
0

A task aborted status (TAS) bit set to zero specifies that aborted tasks shall be terminated by the device server without any
response to the application client.

1

A TAS bit set to one specifies that tasks aborted by the actions of an I_T nexus other than the I_T nexus on which the command
was received shall be terminated with a TASK ABORTED status (see SAM-5).

ATMPE bit
0
1

An application tag mode page enabled (ATMPE) bit set to zero specifies that the Application Tag mode page (see 4.3.6) is disabled
and the contents of logical block application tags are not defined by this standard.
An ATMPE bit set to one specifies that the Application Tag mode page is enabled.
If:
a. the ATMPE is set to one;
b. the ATO bit is set to one;
c. the value in the DPICZ bit allows protection information checking for the specified command; and
d. the APP_CHK bit is set to one in the Extended INQUIRY VPD page (see 4.4.7);
then:
knowledge of the value of the Application Tag shall come from the values in the Application Tag mode page as specified by the
DPICZ bit.

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RWWP bit
0

A reject write without protection (RWWP) bit set to zero specifies that the device server shall process write commands that are
specified to include user data without protection information (e.g., a WRITE(10) command with the WRPROTECT field set to 000b
(see 3.60)).

1

A RWWP bit set to one specifies that the device server in a logical unit that has been formatted with protection information shall terminate with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to
INVALID FIELD IN CDB any write command that is specified to include user data without protection information.

AUTOLOAD MODE field
The AUTOLOAD MODE field specifies the action to be taken by a removable medium device server when a medium is inserted. For
devices other than removable medium devices, this field is reserved. Table 307 shows the usage of the AUTOLOAD MODE field.
Table 307

AUTOLOAD MODE field

Code

Definition

000b

Medium shall be loaded for full access.

001b

Medium shall be loaded for medium auxiliary memory access only.

010b

Medium shall not be loaded.

011b - 111b

Reserved

READY AER HOLDOFF PERIOD field
The READY AER HOLDOFF PERIOD field specifies the minimum time in milliseconds after the target starts its initialization sequence that
it shall delay before attempting to issue an asynchronous event report. This value may be rounded up.
Note.

This field has been declared obsolete by the T10 committee and are not supported.

BUSY TIMEOUT PERIOD field
The BUSY TIMEOUT PERIOD field specifies the maximum time, in 100 milliseconds increments, that the application client allows for the
device server to return BUSY status for unanticipated conditions that are not a routine part of commands from the application client. This
value may be rounded down as defined in Section 2.3. A 0000h value in this field is undefined by this manual. An FFFFh value in this field
is defined as an unlimited period.
EXTENDED SELF-TEST COMPLETION TIME field
The EXTENDED SELF-TEST COMPLETION TIME field contains advisory data that is the time in seconds that the device server requires
to complete an extended self-test when the device server is not interrupted by subsequent commands and no errors occur during processing of the self-test. The application client should expect this time to increase significantly if other commands are sent to the logical unit
while a self-test is in progress or if errors occur during the processing of the self-test. Device servers supporting SELF-TEST CODE field
values other than 000b for the SEND DIAGNOSTIC command (see 3.47) shall support the EXTENDED SELF-TEST COMPLETION TIME
field. The EXTENDED SELF-TEST COMPLETION TIME field is not changeable.

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4.3.10

Control Extension mode page (0Ah/ 01h)

The Control Extension mode page (see table 308) is a subpage of the Control mode page (see 4.3.9) and provides controls over SCSI
features that are applicable to all device types. The mode page policy (see 4.4.12) for this mode page shall be shared. If a field in this
mode page is changed while there is a task already in the task set, it is vendor specific whether the old or new value of the field applies to
that task.
Table 308

Control Extension mode page

Bit
Byte

7

6

0

PS

SPF (1b)

5

4

2

1

0

PAGE CODE (0Ah)
SUBPAGE CODE (01h)

1
2

3

(MSB)

PAGE LENGTH (1Ch)

3
Reserved

4

TCMOS

Reserved

5

(LSB)
SCSIP

IALUAE

INITIAL COMMAND PRIORITY
MAXIMUM SENSE DATA LENGTH

6
7

Reserved

...
31

The PS bit, SPF bit, PAGE CODE field, SUBPAGE CODE field, and PAGE LENGTH field are described in 4.3.5.
TCMOS (Timestamp Changeable By Methods Outside this manual) bit
1

A timestamp changeable by methods outside this manual (TCMOS) bit set to one specifies that the timestamp may be initialized by
methods outside the scope of this manual.

0

A TCMOS bit set to zero specifies that the timestamp shall not be changed by any method except those defined by this manual.

SCSIP (SCSI precedence) bit
1

A SCSI precedence (SCSIP) bit set to one specifies that the timestamp changed using a SET TIMESTAMP command shall take
precedence over methods outside the scope of this manual.

0

A SCSIP bit set to zero specifies that methods outside this manual may change the timestamp and that the SET TIMESTAMP command is illegal.

IALUAE (Implicit Asymmetric Logical Unit Access Enabled) bit
1
An Implicit Asymmetric Logical Unit Access Enabled (IALUAE) bit set to one specifies that implicit asymmetric logical unit access
state changes are allowed.
0
An IALUAE bit set to zero specifies that implicit asymmetric logical unit access state changes be disallowed and indicates that
implicit asymmetric logical unit access state changes are disallowed or not supported.
INITIAL COMMAND PRIORITY field
The INITIAL COMMAND PRIORITY field specifies the priority that may be used as the task priority (see SAM-5) for tasks received by the
logical unit on any I_T nexus (i.e., on any I_T_L nexus) where a priority has not been modified by a SET PRIORITY command. If a MODE
SELECT command specifies an INITIAL COMMAND PRIORITY value that is different than the current INITIAL PRIORITY, then the device
server shall set any priorities that have not be set with a SET PRIORITY command to a value different than the new initial priority value to
the new priority. The device server shall establish a unit attention condition for the initiator port associated with every I_T_L nexus that
receives a new priority, with the additional sense code set to PRIORITY CHANGED.
MAXIMUM SENSE DATA LENGTH field
The MAXIMUM SENSE DATA LENGTH field specifies the maximum number of bytes of sense data the device server shall return in the
same I_T_L_Q nexus transaction as the status. A MAXIMUM SENSE DATA LENGTH field set to zero specifies that there is no limit. The
device server shall not return more sense data bytes in the same I_T_L_Q nexus transaction as the status than the smaller of the length
indicated by the:
a. MAXIMUM SENSE DATA LENGTH field; and
b. MAXIMUM SUPPORTED SENSE DATA LENGTH field in the Extended INQUIRY VPD page (see 4.4.7).

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4.3.11

Disconnect-Reconnect mode page (02h)

The Disconnect-Reconnect mode page (see table 309) provides the application client the means to tune the performance of the service
delivery subsystem. The name for this mode page, disconnect-reconnect, comes from the SCSI parallel interface. The mode page policy
(see 4.4.12) for this mode page shall be shared or per target port. If the SCSI target device contains more than one target port, the mode
page policy should be per target port.
For Parallel SCSI, see Section 4.3.11.1 on page 270.
For Fibre Channel (FC), see Section 4.3.11.2 on page 273.
For Serial Attached SCSI (SAS), see Section 4.3.11.3 on page 275.
4.3.11.1

Disconnect-Reconnect mode page for Parallel SCSI

The Disconnect-Reconnect mode page controls parameters that affect one or more target ports. The parameters that may be implemented
are specified in the SCSI transport protocol standard for the target port.
Table 309

Disconnect-Reconnect mode page

Bit
Byte

7

6

5

0

PS

SPF (0b)

4

3

PAGE LENGTH (0Eh)

2

BUFFER FULL RATIO

3

BUFFER EMPTY RATIO
BUS INACTIVITY LIMIT
(MSB)

(MSB)

(MSB)

EMDP

FAIR ARBITRATION

DIMM

(LSB)
DTDC

Reserved

13
14

(LSB)

MAXIMUM BURST SIZE

11
12

(LSB)

CONNECT TIME LIMIT

9
10

(LSB)

DISCONNECT TIME LIMIT

7
8

0

(MSB)

5
6

1

PAGE CODE (02h)

1

4

2

(MSB)

15

FIRST BURST SIZE

(LSB)

The parameters for a target port affect its behavior regardless of which initiator port is forming an I_T nexus with the target port. The
parameters may be accessed by MODE SENSE (see 3.11) and MODE SELECT (see 3.9) commands directed to any logical unit
accessible through the target port. If a parameter value is changed, all the device servers for all logical units accessible through the target
port shall establish a unit attention condition for the initiator port associated with every I_T nexus that includes the target port except the
I_T nexus on which the MODE SELECT command was received, with the additional sense code set to MODE PARAMETERS CHANGED.
If a parameter that is not appropriate for the specific SCSI transport protocol implemented by the target port is non-zero, the command
shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to
INVALID FIELD IN PARAMETER LIST.
An interconnect tenancy is a period of time during which a given pair of SCSI ports (i.e., an initiator port and a target port) are accessing
the interconnect layer to communicate with each other (e.g., on arbitrated interconnects, a tenancy typically begins when a SCSI port
successfully arbitrates for the interconnect and ends when the SCSI port releases the interconnect for use by other devices). Data and
other information transfers take place during interconnect tenancies.
PS bit, SPF bit, PAGE CODE field, and PAGE LENGTH field
The PS bit, SPF bit, PAGE CODE field, and PAGE LENGTH field are described in 4.3.5.

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BUFFER FULL RATIO field
The BUFFER FULL RATIO field specifies to the target port how full the buffer should be during read operations prior to requesting an interconnect tenancy. Target ports that do not implement the requested ratio should round down to the nearest implemented ratio as defined in
2.3.
BUFFER EMPTY RATIO field
The BUFFER EMPTY RATIO field specifies to the target port how empty the buffer should be during write operations prior to requesting an
interconnect tenancy. Target ports that do not implement the requested ratio should round down to the nearest implemented ratio as
defined in 2.3.
The buffer full and buffer empty ratios are numerators of a fractional multiplier that has 256 as its denominator. A value of zero indicates
that the target port determines when to request an interconnect tenancy consistent with the disconnect time limit parameter. These
parameters are advisory to the target port.
Note.

As an example, consider a target port with ten 512-byte buffers and a specified buffer full ratio of 3Fh. The formula is: INTEGER ((ratio/256)*number of buffers). Therefore in this example INTEGER((3Fh/256)*10) = 2. During the read operations
described in this example, the target port should request an interconnect tenancy whenever two or more buffers are full.

BUS INACTIVITY LIMIT field
The BUS INACTIVITY LIMIT field specifies the maximum time that the target port is permitted to maintain an interconnect tenancy without
data or information transfer. If the bus inactivity limit is exceeded, then the target port shall conclude the interconnect tenancy, within the
restrictions placed on it by the applicable SCSI transport protocol. The contents of the DTDC field in this mode page also shall affect the
duration of an interconnect tenancy. This value may be rounded as defined in 2.3. A value of zero specifies that there is no bus inactivity
limit. Different SCSI transport protocols define different units of measure for the bus inactivity limit.
DISCONNECT TIME LIMIT field
The DISCONNECT TIME LIMIT field specifies the minimum time that the target port shall wait between interconnect tenancies. This value
may be rounded. A value of zero specifies that there is no disconnect time limit. Different SCSI transport protocols define different units of
measure for the disconnect time limit.
CONNECT TIME LIMIT field
The CONNECT TIME LIMIT field specifies the maximum duration of a single interconnect tenancy. If the connect time limit is exceeded,
then the target port shall conclude the interconnect tenancy, within the restrictions placed on it by the applicable SCSI transport protocol.
The contents of the DTDC field in this mode page also shall affect the duration of an interconnect tenancy. This value may be rounded. A
value of zero specifies that there is no connect time limit. Different SCSI transport protocols define different units of measure for the connect time limit.
MAXIMUM BURST SIZE field
The MAXIMUM BURST SIZE field indicates the maximum amount of data that the target port shall transfer during a single data transfer
operation. This value is expressed in increments of 512 bytes (i.e., a value of one means 512 bytes, two means 1 024 bytes, etc.). The
relationship, if any, between data transfer operations and interconnect tenancies is defined in the individual SCSI transport protocol standards. A value of zero specifies there is no limit on the amount of data transferred per data transfer operation.
In terms of the SCSI transport protocol services, the device server shall limit the Request Byte Count argument to the Receive Data-Out
protocol service and the Send Data-In protocol service to the amount specified in the MAXIMUM BURST SIZE field.

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EMDP (Enable Modify Data Pointers) bit
The enable modify data pointers (EMDP) bit specifies whether or not the target port may transfer data out of order.
0

If the EMDP bit is set to zero, the target port shall not transfer data out of order.

1

If the EMDP bit is set to one, the target port is allowed to transfer data out of order.

FAIR ARBITRATION field
The FAIR ARBITRATION field specifies whether the target port should use fair or unfair arbitration when requesting an interconnect tenancy. The field may be used to specify different fairness methods as defined in the individual SCSI transport protocol standards.
DIMM (Disconnect Immediate) bit
0

A disconnect immediate (DIMM) bit set to zero specifies that the target port may transfer data for a command during the same interconnect tenancy in which it receives the command. Whether or not the target port does so may depend upon the target port’s internal algorithms, the rules of the applicable SCSI transport protocol, and settings of the other parameters in this mode page.

1

A disconnect immediate (DIMM) bit set to one specifies that the target port shall not transfer data for a command during the same
interconnect tenancy in which it receives the command.

DTDC (Data Transfer Disconnect Control) field
The data transfer disconnect control (DTDC) field (see table 310) defines other restrictions on when multiple interconnect tenancies are
permitted. A non-zero value in the DTDC field shall take precedence over other interconnect tenancy controls represented by other fields
in this mode page.
Table 310

Data transfer disconnect control

DTDC

Description

000b

Data transfer disconnect control is not used. Interconnect tenancies are controlled by other fields in this
mode page.

001b

All data for a command shall be transferred within a single interconnect tenancy.

010b

Reserved

011b

All data and the response for a command shall be transferred within a single interconnect tenancy.

100b - 111b

Reserved

FIRST BURST SIZE field
The FIRST BURST SIZE field specifies the maximum amount of data that may be transferred to the target port for a command along with
the command (i.e., the first burst). This value is expressed in increments of 512 bytes (i.e., a value of one means 512 bytes, two means 1
024 bytes, etc.). The meaning of a value of zero is SCSI transport protocol specific. SCSI transport protocols supporting this field shall provide an additional mechanism to enable and disable the first burst function.
In terms of the SCSI transport protocol services, the Receive Data-Out protocol service shall retrieve the first FIRST BURST SIZE amount
of data from the first burst.

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4.3.11.2
4.3.11.2.1

Disconnect-Reconnect mode page for FCP
Overview and format of Disconnect-Reconnect mode page for FCP

The Disconnect-Reconnect mode page for FCP (see Table 311) allows the application client to modify the behavior of the service delivery
subsystem. This subclause specifies the parameters that are used by FCP devices and defines how FCP devices interpret the parameters.
The application client communicates with the device server to determine what values are most appropriate for a device server. The device
server communicates the parameter values in this mode page to the target FCP_Port, normally the Fibre Channel interface circuitry. This
communication is internal to the SCSI target device and FCP device and is outside the scope of this manual. If a field or bit contains a
value that is not supported by the FCP device, the device server shall return CHECK CONDITION status. The sense key shall be set to
ILLEGAL REQUEST and the additional sense code set to ILLEGAL FIELD IN PARAMETER LIST.
Table 311

Disconnect-Reconnect mode page (02h)

Bit
Byte

7

6

0

PS

Reserved

5

4

3

1

PAGE LENGTH (0Eh)

2

BUFFER FULL RATIO

3

BUFFER EMPTY RATIO
(MSB)

BUS INACTIVITY LIMIT

(LSB)

5
6

(MSB)

DISCONNECT TIME LIMIT

(LSB)

7
8

(MSB)

CONNECT TIME LIMIT

(LSB)

9
10

(MSB)

MAXIMUM BURST SIZE

(LSB)

11
12

EMDP

FAA

FAB

FAC

Restricted

Restricted

Reserved

13
14

0

PAGE CODE (02h)

1

4

2

(MSB)

FIRST BURST SIZE

15

(LSB)

An interconnect tenancy is the period of time when an FCP device owns or may access a shared Fibre Channel interconnect. For
arbitrated loops (see FC-AL-2) and Fibre Channel Class 1 connections, a tenancy typically begins when an FCP device successfully opens
the connection and ends when the FCP device releases the connection for use by other device pairs. Data and other information transfers
take place during interconnect tenancies.
Point-to-point or fabric-attached Class 2 or Class 3 links and many other configurations do not have a concept of interconnect tenancy and
may perform transfers at any time.
BUFFER FULL RATIO field
The BUFFER FULL RATIO field indicates to the device server, during read operations, how full the buffer should be prior to requesting an
interconnect tenancy. Device servers that do not implement the requested ratio should round down to the nearest implemented ratio as
defined in 2.3. FCP devices attached to links that do not have the concept of interconnect tenancy shall round the ratio to zero and transmit
data in a vendor specific manner.
The value contained in the BUFFER FULL RATIO field is defined by 4.3.11.1.
BUFFER EMPTY RATIO field
The BUFFER EMPTY RATIO field indicates to the device server, during write operations, how empty the buffer should be prior to transmitting an FCP_XFER_RDY IU that requests the initiator FCP_Port to send data. Device servers that do not implement the requested ratio
should round down to the nearest implemented ratio as defined in 2.3.
The value contained in the BUFFER EMPTY RATIO field is defined by 4.3.11.1.

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BUS INACTIVITY LIMIT field
The BUS INACTIVITY LIMIT field indicates the maximum time that the target FCP_Port is permitted to maintain an interconnect tenancy
without data or information transfer, measured in transmission word increments. If the bus inactivity limit is exceeded or if the bus is inactive and the target FCP_Port holding the bus detects that the limit is going to be exceeded, the device server shall end the interconnect
tenancy. This value may be rounded as defined in 2.3. A value of zero indicates that there is no bus inactivity limit.
Note.

Because of the low overheads associated with initiating and closing bus tenancy on Fibre Channel links, device servers should
end tenancies immediately upon completing the required transfers.

The BUS INACTIVITY LIMIT field is not applicable for FCP devices attached to links that do not have the concept of interconnect tenancy.
DISCONNECT TIME LIMIT field
The DISCONNECT TIME LIMIT field indicates the minimum delay between interconnect tenancies measured in increments of 128 transmission words. Target FCP_Ports in configurations having the concept of interconnect tenancy shall delay at least this time interval after
each interconnect tenancy before beginning arbitration. The device server may round this value to any value it prefers. A value of zero indicates that the disconnect time limit does not apply.
The DISCONNECT TIME LIMIT field is not applicable for FCP devices attached to links that do not have the concept of interconnect tenancy.
CONNECT TIME LIMIT field
The CONNECT TIME LIMIT field indicates the maximum duration of a single interconnect tenancy, measured in increments of 128 transmission words. If the connect time limit is exceeded the device server shall conclude the interconnect tenancy, within the restrictions
placed on it by the applicable Fibre Channel configuration. The device server may round this value to any value it prefers. A value of zero
indicates that there is no connect time limit.
The CONNECT TIME LIMIT field is not applicable for FCP devices attached to links that do not have the concept of interconnect tenancy.
MAXIMUM BURST SIZE field
The MAXIMUM BURST SIZE field indicates the maximum size of all bytes in an FCP_DATA IU that the target FCP_Port shall transfer to
the initiator FCP_Port in a single Data-In FCP_DATA IU or request from the initiator FCP_Port in an FCP_XFER_RDY IU. This parameter
does not affect how much data is transferred in a single interconnect tenancy. This value is expressed in increments of 512 bytes (e.g., a
value of 1 means 512 bytes, two means 1024 bytes, etc.). The device server may round this value down as defined in 2.3. A value of zero
indicates there is no limit on the amount of data transferred per data transfer operation. This value shall be implemented by all FCP
devices. The initiator FCP_Port and target FCP_Port may use the value of this parameter to adjust internal maximum buffering requirements.
EMDP bit
The enable modify data pointers (EMDP) bit indicates whether or not the target FCP_Port may use the random buffer access capability to
reorder FCP_DATA IUs for a single SCSI command. If the EMDP bit is set to zero, the target FCP_Port shall generate continuously
increasing relative offset values for each FCP_DATA IU for a single SCSI command.
1

If the EMDP bit is set to one, the target FCP_Port may transfer the FCP_DATA IUs for a single SCSI command in any order.

0

If the EMDP bit is set to zero, data overlay is prohibited even if it is allowed by the state of the PRLI FCP Service Parameter page
DATA OVERLAY ALLOWED bit.

The EMDP bit does not affect the order of frames within a Sequence. The enable modify data pointers function is optional for all FCP
devices.
For bidirectional commands, the EMDP bit applies independently to the read operation and write operation. If the EMDP bit is set to zero,
the target FCP_Port shall generate continuously increasing relative offset values for the read operation and the write operation, but there is
no read operation to write operation or write operation to read operation ordering requirement.
FAA, FAB, FAC bits
The fairness access (FA) bits, FAA, FAB, and FAC, indicate whether a target FCP_Port attached to an arbitrated loop (see FC-AL-2) shall
use the access fairness algorithm when beginning the interconnect tenancy.
1

An FA bit set to one indicates that the target FCP_Port shall use the access fairness algorithm for the specified frames.

0

An FA bit set to zero indicates that the target FCP_Port may choose to not use the access fairness algorithm.

The FAA bit controls arbitration when the target FCP_Port has one or more FCP_DATA IU frames to send to an initiator FCP_Port.
The FAB bit controls arbitration when the target FCP_Port has one or more FCP_XFER_RDY IU frames to send to an initiator FCP_Port.
The FAC bit controls arbitration when the target FCP_Port has an FCP_RSP IU frame to send to an initiator FCP_Port.
If the target FCP_Port intends to send multiple frame types, it may choose to not use the access fairness algorithm if any applicable FA bit
is set to zero. FCP devices attached to links that do not have the concept of interconnect tenancy shall ignore the FA bits. The FA bits are
optional for all FCP devices.

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FIRST BURST SIZE field
When the WRITE FCP_XFER_RDY DISABLED bit is negotiated as being set to one in the PRLI FCP Service Parameter page, the FIRST
BURST SIZE field indicates the maximum amount of all bytes that shall be transmitted in the first FCP_DATA IU sent from the initiator
FCP_Port to the target FCP_Port. If all data is transmitted in the first IU, no subsequent FCP_XFER_RDY IUs shall be transmitted by the
target FCP_Port. If the maximum amount of data has been transmitted, but more data remains to be transferred, the target FCP_Port shall
request that data with subsequent FCP_XFER_RDY IUs.
When the WRITE FCP_XFER_RDY DISABLED bit is negotiated as being set to zero in the PRLI FCP Service Parameter page, the FIRST
BURST SIZE field is ignored and permission to transmit data from the initiator FCP_Port to the target FCP_Port is managed using FCP_XFER_RDY IUs. For data transmissions from the target FCP_Port to the initiator FCP_Port, the FIRST BURST SIZE field is ignored.
The FIRST BURST SIZE field value is expressed in increments of 512 bytes (e.g., a value of one means 512 bytes, two means 1024
bytes). A value of zero indicates that there is no first burst size limit. The FIRST BURST SIZE field shall be implemented by all FCP
devices that support the WRITE FCP_XFER_RDY DISABLED bit being set to one. The application client and device server may use the
value of this parameter to adjust internal maximum buffering requirements.
4.3.11.3
4.3.11.3.1

Disconnect-Reconnect mode page for SAS
Disconnect-Reconnect mode page overview

The Disconnect-Reconnect mode page for SAS provides the application client the means to tune the performance of the service delivery
subsystem. Table 312 defines the parameters which are applicable to SSP. If any field in the Disconnect-Reconnect mode page is not
implemented, the value assumed for the functionality of the field shall be zero (i.e., as if the field in the mode page is implemented and the
field is set to zero).
The application client sends the values in the fields to be used by the device server to control the SSP connections by means of a MODE
SELECT command. The device server shall then communicate the field values to the SSP target port. The field values are communicated
from the device server to the SSP target port in a vendor-specific manner.
SAS devices shall only use the parameter fields defined below in Table 312. If any other fields within the Disconnect-Reconnect mode
page of the MODE SELECT command contain a non-zero value, the device server shall terminate the MODE SELECT command with
CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN
PARAMETER LIST.
Table 312

Disconnect-Reconnect mode page for SAS

Bit
Byte

7

6

0

PS

Reserved

5

4

3

PAGE LENGTH (0Eh)

2

Reserved

3

Reserved
(MSB)

5

BUS INACTIVITY TIME LIMIT

6

(MSB)

9
10

(MSB)

11

MAXIMUM CONNECT TIME LIMIT

MAXIMUM BURST SIZE

12

Restricted

13

Reserved

14

0

(LSB)

Reserved

7
8

1

PAGE CODE (02h)

1

4

2

(MSB)

15

FIRST BURST SIZE

(LSB)

(LSB)

(LSB)

The PARAMETERS SAVEABLE (PS) bit is defined in 4.3.5.
The PAGE CODE (PS) field shall be set to 02h.
The PAGE LENGTH field shall be set to 0Eh.
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BUS INACTIVITY TIME LIMIT field
The value in the BUS INACTIVITY TIME LIMIT field contains the maximum period that an SSP target port is permitted to maintain a connection without transferring a frame to the SSP initiator port. This value shall be the number of 100 ms increments between frames that the
SSP target port transmits during a connection. When this number is exceeded, the SSP target port shall prepare to close the connection
(i.e., by requesting to have the link layer transmit DONE). This value may be rounded as defined in 2.3. A value of zero in this field shall
specify that there is no bus inactivity time limit.
MAXIMUM CONNECT TIME LIMIT field
The value in the MAXIMUM CONNECT TIME LIMIT field contains the maximum duration of a connection. This value shall be the number
of 100 ms increments that an SSP target port transmits during a connection after which the SSP target port shall prepare to close the connection (e.g., a value of one in this field means that the time is less than or equal to 100 ms and a value of two in this field means that the
time is less than or equal to 200 ms). If an SSP target port is transferring a frame when the maximum connection time limit is exceeded, the
SSP target port shall complete transfer of the frame before preparing to close the connection. A value of zero in this field shall specify that
there is no maximum connection time limit. The maximum connection time limit is enforced by the port layer. This value may be rounded as
defined in 2.3.
MAXIMUM BURST SIZE field
For read data, the value in the MAXIMUM BURST SIZE field contains the maximum amount of data that is transferred during a connection
by an SSP target port per I_T_L_Q nexus without transferring at least one frame for a different I_T_L_Q nexus. If the SSP target port:
a) has read data to transfer for only one I_T_L_Q nexus, and
b) has no requests to transfer write data for any I_T_L_Q nexus;
then the SSP target port shall prepare to close the connection after the amount of data specified by the MAXIMUM BURST SIZE field is
transferred to the SSP initiator port.
For write data, the value shall specify the maximum amount of data that an SSP target port requests via a single XFER_RDY frame.
This value shall be specified in 512-byte increments (e.g., a value of one in this field means that the number of bytes transferred to the SSP
initiator port for the nexus is less than or equal to 512 and a value of two in this field means that the number of bytes transferred to the SSP
initiator port for the nexus is less than or equal to 1 024). The device server may round this value down as defined in 2.3. A value of zero in
this field shall specify that there is no maximum burst size.
In terms of the SCSI transport protocol services, the device server shall limit the Request Byte Count argument to the Receive Data-Out ()
protocol service and the Send Data-In () protocol service to the amount specified in this field.
FIRST BURST SIZE field
If the ENABLE FIRST BURST field in the COMMAND frame is set to zero, the FIRST BURST SIZE field is ignored.
If the ENABLE FIRST BURST field in the COMMAND frame is set to one, the value in the FIRST BURST SIZE field contains the maximum
amount of write data in 512-byte increments that may be sent by the SSP initiator port to the SSP target port without having to receive an
XFER_RDY frame from the SSP target port (e.g., a value of one in this field means that the number of bytes transferred by the SSP initiator port is less than or equal to 512 and a value of two in this field means that the number of bytes transferred by the SSP initiator port is
less than or equal to 1 024).
Specifying a non-zero value in the FIRST BURST SIZE field is equivalent to an implicit XFER_RDY frame for each command requiring
write data where the WRITE DATA LENGTH field of the XFER_RDY frame is set to 512 times the value of the FIRST BURST SIZE field
The rules for data transferred using the value in the FIRST BURST SIZE field are the same as those used for data transferred for an
XFER_RDY frame (i.e., the number of bytes transferred using the value in the FIRST BURST SIZE field is as if that number of bytes was
requested by an XFER_RDY frame).
If the amount of data to be transferred for the command is less than the amount of data specified by the FIRST BURST SIZE field, the SSP
target port shall not transmit an XFER_RDY frame for the command. If the amount of data to be transferred for the command is greater
than the amount of data specified by the FIRST BURST SIZE field, the SSP target port shall transmit an XFER_RDY frame after it has
received all of the data specified by the FIRST BURST SIZE field from the SSP initiator port. All data for the command is not required to be
transferred during the same connection in which the command is transferred.
A value of zero in this field shall specify that there is no first burst size (i.e., an SSP initiator port shall transmit no write DATA frames to the
SSP target port before receiving an XFER_RDY frame).

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4.3.12

Format Parameters page (03h)

This mode page has been declared obsolete by the T10 committee. However, it is included because it may be implemented on some
products.
The Format Parameters page implementation is defined in Table 313. This table summarizes the function and defines the default or
changeability status for each bit. The actual implementation of reserving spare areas for defect management takes place during the
FORMAT UNIT command.
In Table Note., zone refers to defect management zone (one or more tracks), not a ZBR (variable track capacity recording)
zone.ZBR zones are referred to as notches (page 0Ch is the Notch page).

Note.

Table 313

Format Parameters page (03h)

Bit
Byte

7

6

0

PS

Reserved

5

4

3

2

PAGE LENGTH (16h)

2,3

TRACKS PER ZONE

4,5

ALTERNATE SECTORS PER ZONE

6,7

ALTERNATE TRACKS PER ZONE

8,9

ALTERNATE TRACKS PER VOLUME

10,11

SECTORS PER TRACK

12,13

DATA BYTES PER PHYSICAL SECTOR

14,15

INTERLEAVE

16,17

TRACK SKEW FACTOR

18,19

CYLINDER SKEW FACTOR
SSEC

HSEC

0

PAGE CODE (03h)

1

20

1

RMB

21,22,23

SURF

DRIVE TYPE

Reserved

PS (Page Savable) bit
The only time this page of parameters may be sent is immediately before sending a FORMAT UNIT command to the drive. The Current
parameters for this page are updated immediately but any changes between these Current parameters and the existing media format are
not in effect until after the FORMAT UNIT command is completed. A PS bit of 1 indicates this page is savable. The PS bit is not used with
the MODE SELECT command.
The PAGE CODE (PS) field shall be set to 03h.
The PAGE LENGTH field shall be set to 16h.
TRACKS PER ZONE field
The TRACKS PER ZONE field indicates the number of tracks the drive allocates to each defect management zone. A zone can be one or
more tracks or one or more cylinders. See individual drive’s Product Manual, Volume 1, for number of tracks allocated to each defect management zone for that drive model.

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ALTERNATE SECTORS PER ZONE field
The ALTERNATE SECTORS PER ZONE field indicates the number of spare sectors to be reserved for the defined defect management
zone. A value of zero indicates that no sectors are to be reserved in each zone for defect management. This is to accommodate hosts that
want to manage the defects themselves.
ALTERNATE TRACKS PER ZONE field
The ALTERNATE TRACKS PER ZONE field indicates the number of spare tracks to be reserved at the end of each defect management
zone. A value of zero indicates that no spare tracks are to be reserved in each zone for defect management by the drive.
ALTERNATE TRACKS PER VOLUME field
The ALTERNATE TRACKS PER VOLUME field indicates the number of spare tracks to be reserved at the end of the drive volume. The
drive uses these locations for replacing defective sectors. A value of zero indicates that no spare tracks are to be reserved at the end of the
unit for defect management. The initiator may change this value for a number between 0 and 255 that is a multiple of the total number of
Data Read/Write heads installed. However, it is not changeable on some products.
SECTORS PER TRACK field
The SECTORS PER TRACK field indicates the average number of physical sectors the drive has per disk track. This value depends on the
selected sector size and ZBR zones. The number of user accessible sectors per track may be fewer than the reported value, since sectors
per Track includes sectors set aside for defect management. This value cannot be used to calculate drive user accessible capacity.
Note.

The value cannot be directly selected with the MODE SELECT command, but is a report of how the drive is configured.

DATA BYTES PER PHYSICAL SECTOR field
The DATA BYTES PER PHYSICAL SECTOR field indicates the number of data bytes the drive shall allocate per physical sector. This
value equals the block length reported in the MODE SENSE block descriptor. The bytes per physical sector is not directly changeable by
the initiator and is not verified on a MODE SELECT command.
INTERLEAVE field
The INTERLEAVE field is the interleave value sent to the drive during the last FORMAT UNIT command.
Note.

This field is valid only for MODE SENSE commands. The drive ignores this field during MODE SELECT commands.

TRACK SKEW FACTOR field
The TRACK SKEW FACTOR field indicates the average number of physical sectors between the last logical block on one track and the
first logical block on the next sequential track of the same cylinder. A value of zero indicates no skew.
Note.

This value is not changeable by a SCSI initiator port.

CYLINDER SKEW FACTOR field
The CYLINDER SKEW FACTOR field indicates the average number of physical sectors between the last logical block of one cylinder and
the first logical block of the next cylinder. A value of zero indicates no skew. Cylinder skew will be utilized by a drive but is not changeable
by a SCSI initiator port.
SSEC bit set and HSEC bits
A HSEC bit set to one indicates that the target shall use hard sector formatting. The HSEC bit and the SSEC bit are mutually exclusive in
MODE SELECT commands.
Possible combinations of MODE SENSE Report Default Values:
SSEC

HSEC

0

0

Target shall not return this combination

1

0

Target supports Soft sector formatting only

0

1

Target supports Hard sector formatting only

1

1

Target supports both Soft and Hard sector formatting

Possible combinations of MODE SENSE Report Changeable Values
SSEC

HSEC

0

0

Sector formatting Not changeable

1

0

Target shall not return this combination

0

1

Target shall not return this combination

1

1

Target supports both Soft and Hard sector formatting

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RMB (Removable Medium) bit
0

A removable medium (RMB) bit set to zero indicates that the medium is not removable.

1

A RMB bit set to one indicates that the medium is removable.

SURF (Surface) bit
The SURF (Surface) bit indicates how the target shall map the logical block addressing into physical block addressing.
0

A SURF bit set to zero indicates that the target shall allocate progressive addresses to all sectors within a cylinder prior to allocating
sector addresses to the next cylinder.

1

A SURF bit set to one indicates that the target shall allocate progressive addresses to all sectors on a surface prior to allocating
sector addresses to the next surface.

DRIVE TYPE field
The DRIVE TYPE field bits are defined as follows:
a) The Hard Sectoring (HSEC) bit (bit 6) set to one indicates the drive shall use hard sector formatting.
b) Bits 0-5, and 7 are not implemented by the drive and are always zero. All bits (0-7) are not changeable.
c) See individual drive’s Product Manual, Volume 1, MODE SENSE Data clause for changeable values.
4.3.13

Informational Exceptions Control mode page (1Ch)

The Informational Exceptions Control mode page (see table 314) defines the methods used by the device server to control the reporting
and the operations of specific informational exception conditions. This page shall only apply to informational exceptions that report an
additional sense code of FAILURE PREDICTION THRESHOLD EXCEEDED or an additional sense code of WARNING to the application
client. The mode page policy (see 4.4.12) for this mode page shall be shared, or per I_T nexus.
Informational exception conditions occur as the result of vendor specific events within a logical unit. An informational exception condition
may occur asynchronous to any commands issued by an application client.
Storage devices that support SMART (Self-Monitoring Analysis and Reporting Technology) for predictive failure software
should use informational exception conditions..

Note.

Table 314
Bit
Byte
0
1
2
3
4
...
7
8
...
11

Informational Exceptions Control mode page
7

6

PS

SPF (0b)

PERF

5

Reserved
EBF
Reserved

4

3

2

PAGE CODE (1Ch)
PAGE LENGTH (0Ah)
EWASC
DEXCPT
TEST

1

EBACKERR
MRIE

0

LOGERR

(MSB)
INTERVAL TIMER
(LSB)
(MSB)
REPORT COUNT
(LSB)

PS bit, SPF bit, PAGE CODE field, and PAGE LENGTH field
The PS bit, SPF bit, PAGE CODE field, and PAGE LENGTH field are described in 4.3.5.
PERF (Performance) bit
0

If the performance (PERF) bit is set to zero, informational exception operations that are the cause of delays are acceptable.

1

If the PERF bit is set to one, the device server shall not cause delays while doing informational exception operations. A PERF bit
set to one may cause the device server to disable some or all of the informational exceptions operations, thereby limiting the reporting of informational exception conditions.

EBF (Enable Background Function) bit
1

If background functions are supported and the Enable Background Function (EBF) bit is set to one, then the device server shall
enable background functions.

0

If the EBF bit is set to zero, the device server shall disable the functions. Background functions with separate enable control bits
(e.g., background medium scan defined in 4.3.7 are not controlled by this bit.

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For the purposes of the EBF bit, background functions are defined as idle time functions that may impact performance that are performed
by a device server operating without errors but do not impact the reliability of the logical unit (e.g., read scan).
EWASC (Enable Warning) bit
0

If the enable warning (EWASC) bit is set to zero, the device server shall disable reporting of the warning. The MRIE field is ignored
when DEXCPT is set to one and EWASC is set to zero.

1

If the EWASC bit is set to one, warning reporting shall be enabled. The method for reporting the warning when the EWASC bit is set
to one is determined from the MRIE field.

DEXCPT (Disable Exception Control) bit
0

A disable exception control (DEXCPT) bit set to zero indicates the failure prediction threshold exceeded reporting shall be enabled.
The method for reporting the failure prediction threshold exceeded when the DEXCPT bit is set to zero is determined from the
MRIE field.

1

A DEXCPT bit set to one indicates the device server shall disable reporting of the failure prediction threshold exceeded. The MRIE
field is ignored when DEXCPT is set to one and EWASC is set to zero.

TEST bit
1

A TEST bit set to one shall create a test device failure at the next interval time, as specified by the INTERVAL TIMER field, if the
DEXCPT bit is set to zero. When the TEST bit is set to one, the MRIE and REPORT COUNT fields shall apply as if the TEST bit
were zero. The test device failure shall be reported with the additional sense code set to FAILURE PREDICTION THRESHOLD
EXCEEDED (FALSE). If both the TEST bit and the DEXCPT bit are one, the MODE SELECT command shall be terminated with
CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD
IN PARAMETER LIST.

0

A TEST bit set to zero shall instruct the device server not to generate any test device failure notifications.

EBACKERR (enable background error) bit
0

An enable background error (EBACKERR) bit set to zero indicates the target shall disable reporting of background self-test errors
(SPC-4) and background scan errors (see SBC-3).

1

An EBACKERR bit set to one indicates reporting of background self-test errors and background scan errors shall be enabled. The
method for reporting background self-test errors and background scan errors is determined by contents of the mrie field. Background self-test errors and background scan errors shall be reported as soon as the method specified in the mrie field occurs (i.e.,
the interval timer field and report count field do not apply for background self-test errors and background scan errors).

LOGERR (Log Error) bit
0

If the log errors (LOGERR) bit is set to zero, the logging of informational exception conditions by a device server is vendor specific.

1

If the LOGERR bit is set to one, the device server shall log informational exception conditions.

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MRIE (Method Of Reporting Informational Exceptions) field
The value in the method of reporting informational exceptions (MRIE) field (see table 315) defines the method that shall be used by the
device server to report informational exception conditions. The priority of reporting multiple information exceptions is vendor specific.
Table 315

Method of reporting informational exceptions (MRIE) field

MRIE
0h
1h
2h

Description
No reporting of informational exception condition: The device server shall not report information exception conditions.
Asynchronous event reporting: Obsolete
Generate unit attention: The device server shall report informational exception conditions by establishing a unit attention
condition (see SAM-5) for the initiator port associated with every I_T nexus, with the additional sense code set to indicate
the cause of the informational exception condition.
As defined in SAM-5, the command that has the CHECK CONDITION status with the sense key set to UNIT ATTENTION is
not processed before the informational exception condition is reported.
3h
Conditionally generate recovered error: The device server shall report informational exception conditions, if the reporting
of recovered errors is allowed, a by returning a CHECK CONDITION status. If the TEST bit is set to zero, the status may be
returned after the informational exception condition occurs on any command for which GOOD status or INTERMEDIATE
status would have been returned. If the TEST bit is set to one, the status shall be returned on the next command received
on any I_T nexus that is normally capable of returning an informational exception condition when the test bit is set to zero.
The sense key shall be set to RECOVERED ERROR and the additional sense code shall indicate the cause of the informational exception condition.
The command that returns the CHECK CONDITION for the informational exception shall complete without error before any
informational exception condition may be reported.
4h
Unconditionally generate recovered error: The device server shall report informational exception conditions, regardless
of whether the reporting of recovered errors is allowed, by returning a CHECK CONDITION status. If the TEST bit is set to
zero, the status may be returned after the informational exception condition occurs on any command for which GOOD status or INTERMEDIATE status would have been returned. If the TEST bit is set to one, the status shall be returned on the
next command received on any I_T nexus that is normally capable of returning an informational exception condition when
the TEST bit is set to zero. The sense key shall be set to RECOVERED ERROR and the additional sense code shall indicate the cause of the informational exception condition.
The command that returns the CHECK CONDITION for the informational exception shall complete without error before any
informational exception condition may be reported.
5h
Generate no sense: The device server shall report informational exception conditions by returning a CHECK CONDITION
status. If the TEST bit is set to zero, the status may be returned after the informational exception condition occurs on any
command for which GOOD status or INTERMEDIATE status would have been returned. If the TEST bit is set to one, the
status shall be returned on the next command received on any I_T nexus that is normally capable of returning an informational exception condition when the TEST bit is set to zero. The sense key shall be set to NO SENSE and the additional
sense code shall indicate the cause of the informational exception condition.
The command that returns the CHECK CONDITION for the informational exception shall complete without error before any
informational exception condition may be reported.
6h
Only report informational exception condition on request: The device server shall preserve the informational exception(s) information. To find out about information exception conditions the application client polls the device server by issuing a REQUEST SENSE command. In the REQUEST SENSE parameter data that contains the sense data, the sense key
shall be set to NO SENSE and the additional sense code shall indicate the cause of the informational exception condition.
7h - Bh
Reserved
Ch - Fh
Vendor specific
Error reporting is controlled by the post error (PER) bit in the Read-Write Error Recovery mode page (see 4.3.16).
INTERVAL TIMER field
The value in the INTERVAL TIMER field is the period in 100 millisecond increments for reporting that an informational exception condition
has occurred. The device server shall not report informational exception conditions more frequently than the time specified by the INTERVAL TIMER field and shall report them after the time specified by INTERVAL TIMER field has elapsed. After the informational exception
condition has been reported the interval timer shall be restarted. A value of zero or FFFF FFFF FFFF FFFFh in the INTERVAL TIMER field
indicates that the period for reporting an informational exception condition is vendor specific.
The maintaining of the interval timer and the report counter across power cycles, hard resets, logical unit resets, and I_T nexus losses is
vendor specific.
REPORT COUNT field
The REPORT COUNT field specifies the maximum number of times the device server may report an informational exception condition to
the application client. A value of zero in the REPORT COUNT field indicates there is no limit on the number of times the device server
reports an informational exception condition.

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4.3.14

Power Condition mode page (1Ah)

The Power Condition mode page provides an application client with methods to control the power condition of a logical unit (see 3.12).
These methods include:
a) Specifying that the logical unit transition to a power condition without delay; and
b) Activating and setting of idle condition and standby condition timers to specify that the logical unit wait for a period of inactivity
before transitioning to a specified power condition.
The mode page policy (see 3.9) for this mode page shall be shared.
When a device server receives a command while in a power condition based on a setting in the Power Condition mode page, the logical
unit shall transition to the power condition that allows the command to be processed. If either the idle condition timer or the standby
condition timer has been set, then they shall be reset on receipt of the command. On completion of the command, the timer(s) shall be
started.
Logical units that contain cache memory shall write all cached data to the medium for the logical unit (e.g.,as a logical unit does in
response to a SYNCHRONIZE CACHE command as described in 3.51 and 3.52) prior to entering into any power condition that prevents
accessing the media (e.g., before a hard drive stops its spindle motor during transition to the standby power condition).
The logical unit shall use the values in the Power Condition mode page to control its power condition after a power on or a hard reset until
a START STOP UNIT command setting a power condition is received.
Table 316 defines the Power Condition mode page.
Table 316
Bit
Byte
0
1
2
3
4
...
7
8
...
11
12
...
15
16
...
19
20
...
23
24
...
38
39

Power Condition mode page
7

6

PS

SPF (0b)

PM_BG_PRECEDENCE
Reserved
(MSB)

5

4

3

2

PAGE CODE (1Ah)
PAGE LENGTH (26h)
Reserved
IDLE_C
IDLE_B

1

0

IDLE_A

STANDBY_Y
STANDBY_Z

IDLE_A CONDITION TIMER
(LSB)
(MSB)
STANDBY_Z CONDITION TIMER
(LSB)
(MSB)
IDLE_B CONDITION TIMER
(LSB)
(MSB)
IDLE_C CONDITION TIMER
(LSB)
(MSB)
STANDBY_Y CONDITION TIMER
(LSB)
Reserved
CCF_IDLE

CCF_STANDBY

CCF_STOPPED

Reserved

PS bit, SPF bit, PAGE CODE field, and PAGE LENGTH field
The PS bit, SPF bit, PAGE CODE field, and PAGE LENGTH field are described in 4.3.5.
PM_BG_PRECEDENCE field
The PM_BG_PRECEDENCE field (see Table 317) specifies the interactions between background functions (see SPC-4) and power management.

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The behavior of the idle and standby condition timers controlled by this mode page is defined in the power condition overview and the
power condition state machine (see SPC-4).
Table 317

PM_BG_PRECEDENCE field

Code

Description

00b

Vendor specific

01b

Performing background functions take precedence over maintaining low power conditions as follows:
a) if the logical unit is in a low power condition as the result of a power condition timer associated with that condition
expiring, then:
A) the logical unit shall change from that power condition, if necessary, to the power condition required to perform the
background function, when:
a) a timer associated with a background scan operation expires, and that function is enabled (see SBC-3);
or
b) an event occurs to initiate a device specific background function, and that function is enabled (see SPC-4);
2) the logical unit shall perform the background function(s) based on the definitions in this standard and other command standards (e.g., if the device server receives a command while performing a background function, then the
logical unit shall suspend the function to process the command);
3) if more than one condition is met to initiate a background function, then:
a) all initiated background functions shall be performed; and
b) the order of performing the functions is vendor specific; and
4) when all initiated background functions have been completed, the device server shall check to see if any power
condition timers have expired. If any power condition timer has expired, then the logical unit shall change to the
power condition associated with the highest priority timer that has expired;
or
b) if the logical unit is performing a background function, and a power condition timer expires, then the logical unit shall
perform all initiated background functions before the logical unit changes to a power condition associated with a timer
has expired.

10b

Maintaining low power conditions take precedence over performing background functions as follows:
a) if the logical unit is in a low power condition, then the logical unit shall not change from that power condition to perform
a background function;
b) the device server may perform any initiated and enabled background function based on the definitions in this standard
or other command standards, if all of the following are true:
A) a condition is met to initiate a background function;
B) that background function is enabled;
C) the logical unit changes to a power condition in which the background function may be performed (e.g., the device
server processes a medium access command causing the logical unit to change its power condition to continue
processing that command); and
D) all outstanding application client requests have been completed;
or
c) if the logical unit is performing a background function, and a power condition timer expires that causes a change to a
power condition in which the logical unit is unable to continue performing the background function, then the logical
unit shall:
A) suspend the background function; and
B) change to the power condition associated with the timer that expired.

11b

Reserved

STANDBY_Y bit
1

If the STANDBY_Y bit is set to one, then the standby_y condition timer is enabled.

0

If the STANDBY_Y bit is set to zero, then the device server shall ignore the standby_y condition timer.

IDLE_C bit
1

If the IDLE_C bit is set to one, then the idle_c condition timer is enabled.

0

If the IDLE_C bit is set to zero, then the device server shall ignore the idle_c condition timer.

IDLE_B bit
1

If the IDLE_B bit is set to one, then the idle_b condition timer is enabled.

0

If the IDLE_B bit is set to zero, then the device server shall ignore the idle_b condition timer.

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IDLE_A bit
1

If the IDLE_A bit is set to one, then the idle_a condition timer is enabled.

0

If the IDLE_A bit is set to zero, then the device server shall ignore the idle_a condition timer.

STANDBY_Z bit
1

If the STANDBY_Z bit is set to one, then the standby_z condition timer is enabled.

0

If the STANDBY_Z bit is set to zero, then the device server shall ignore the standby_z condition timer.

If any of the power condition enable bits (e.g., the IDLE_C bit or the STANDBY_Y bit) are set to zero and are not changeable (see
3.11.1.2), then the device server does not implement the power condition timer associated with that enable bit (see SPC-4).
IDLE_A CONDITION TIMER field
The IDLE_A CONDITION TIMER field specifies the initial value, in 100 millisecond increments, for the idle_a power condition timer (see
SPC-4). This value may be rounded up or down to the nearest implemented time as described in 2.3.
STANDBY_Z CONDITION TIMER field
The STANDBY_Z CONDITION TIMER TIMER field specifies the initial value, in 100 millisecond increments, for the standby_z power condition timer (see SPC-4). This value may be rounded up or down to the nearest implemented time as described in 2.3.
IDLE_B CONDITION TIMER field
The IDLE_B CONDITION TIMER field specifies the initial value, in 100 millisecond increments, for the idle_b power condition timer (see
SPC-4). This value may be rounded up or down to the nearest implemented time as described in 2.3.
IDLE_C CONDITION TIMER field
The IDLE_C CONDITION TIMER field specifies the initial value, in 100 millisecond increments, for the idle_c power condition timer (see
SPC-4). This value may be rounded up or down to the nearest implemented time as described in 2.3.
STANDBY_Y CONDITION TIMER field
The STANDBY_Y CONDITION TIMER field specifies the initial value, in 100 millisecond increments, for the standby_y power condition
timer (see SPC-4). This value may be rounded up or down to the nearest implemented time as described in 2.3.
CCF_IDLE field
The Check Condition From idle_c processing control (CCF_IDLE) field is defined in Table 318.
Table 318

CCF_IDLE field

Code
00b
Restricted [a]
If the transition was from an idle_c power condition, returning CHECK CONDITION status is disabled. [b]
01b
If the transition was from an idle_c power condition, returning CHECK CONDITION status is enabled. [b]
10b
11b
Reserved
[a] See SAS-3 for command processing in the Active_Wait state and Idle_Wait state.
[b] For direct-access block devices see the Active_Wait state in SBC-3 for the definition of command processing in
that state. For devices that are not direct-access block devices, see the state in (SPC-4) for the definition of command processing in that state.
CCF_STANDBY field
The CHECK CONDITION From Standby (CCF_STANDBY) field is defined in Table 319.
Table 319

CCF_STANDBY field

Code
00b
Restricted[a] [a]
If transition was from a standby power condition, returning CHECK CONDITION status is disabled. [b]
01b
If transition was from a standby power condition, returning CHECK CONDITION status is enabled. [b]
10b
Reserved
11b
[a] See SAS-3 for command processing in the Active_Wait state and Idle_Wait state.
[b] For direct-access block devices see the Active_Wait state in SBC-3 for the definition of command processing in
that state. For devices that are not direct-access block devices, see the state in (SPC-4) for the definition of command processing in that state.

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CCF_STOPPED field
The CHECK CONDITION if from stopped (CCF_STOPPED) field is defined in Table 320.
Table 320

CCF_STOPPED field

Code
00b
01b
10b
11b

Restricted [a]
If the transition was from a standby power condition, returning CHECK CONDITION is disabled. [b]
If the transition was from a standby power condition, returning CHECK CONDITION is enabled. [b]
Reserved
[a] See SAS-3 for command processing in the Active_Wait state and Idle_Wait state.
[b] For direct-access block devices see the Active_Wait state in SBC-3 for the definition of command processing in
that state. For devices that are not direct-access block devices, see the state in (SPC-4) for the definition of command processing in that state.
4.3.15

Power Consumption Mode page (1Ah/ 01h)

The Power Consumption mode page (see table 321) is a subpage of the Power Conditions mode page ((see 4.3.14) that provides a
method to select a maximum power consumption level while in the active power condition (see SPC-4) based on the contents of the power
consumption descriptors in the Power Consumption VPD page (see 4.4.14) as described in SPC-4. The mode page policy (see 4.4.12) for
this mode page shall be shared.
Table 321
Bit
Byte
0
1
2
3
4
...
6
7
8
...
15

Power Consumption mode page
7

6

PS

SPF (1b)

5

(MSB)

4

3

2

1

0

PAGE CODE (1Ah)
SUBPAGE CODE (01h)
PAGE LENGTH (000Ch)

(LSB)

Reserved
POWER CONSUMPTION IDENTIFIER
Reserved

PS bit, SPF bit, PAGE CODE field, SUBPAGE CODE field and PAGE LENGTH field
The PS bit, SPF bit, PAGE CODE field, SUBPAGE CODE field and PAGE LENGTH field are described in 4.3.5.
SPF bit, PAGE CODE field, SUBPAGE CODE field and PAGE LENGTH field
The SPF bit, PAGE CODE field, SUBPAGE CODE field and PAGE LENGTH field shall be set as shown in table 321 for the Power Consumption mode page.
POWER CONSUMPTION IDENTIFIER field
The POWER CONSUMPTION IDENTIFIER field specifies the power consumption identifier from one of the power consumption descriptors in the Power Consumption VPD page (see 4.4.14) that the device server is to use as described in SPC-4. If none of the power consumption descriptors in the Power Consumption VPD page contain the value in the POWER CONSUMPTION IDENTIFIER field, then the
MODE SELECT command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the
additional sense code set to INVALID FIELD IN PARAMETER LIST.

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4.3.16

Read-Write Error Recovery mode page (01h)

The Read-Write Error Recovery mode page (see table 322) specifies the error recovery parameters the device server shall use during any
command that performs a read or write operation to the medium (e.g., READ commands, WRITE commands, and WRITE AND VERIFY
commands).
Table 322

Read-Write Error Recovery mode page

Bit
Byte
0
1

7

6

PS

Reserved

2

AWRE

ARRE

3
4
5
6
7
8
9
10
11

5

4

3

2

1

0

PAGE CODE (01h)
PAGE LENGTH (0Ah)
ERROR RECOVERY BITS
TB
RC
EER
PER
DTE
DCR
READ RETRY COUNT
Obsolete
Obsolete
Obsolete
Restricted
Reserved
for MMC-6
WRITE RETRY COUNT
Reserved

(MSB)

RECOVERY TIME LIMIT

(LSB)

PS (Parameters Savable) bit
The parameters savable (PS) bit is only used with the MODE SENSE command. This bit is reserved with the MODE SELECT command. A
PS bit set to one indicates that the device server is capable of saving the mode page in a non-volatile vendor-specific location.
PAGE CODE field and PAGE LENGTH field
The PAGE CODE field and PAGE LENGTH field are described in 4.3.5.
AWRE (Automatic Write Reallocation Enabled) bit
0

An automatic write reallocation enabled (AWRE) bit set to zero specifies that the device server shall not perform automatic reallocation of defective logical blocks during write operations.

1

An AWRE bit set to one specifies that the device server shall enable automatic reallocation of defective logical blocks during write
operations. The automatic reallocation shall be performed only if the device server has the valid data (e.g., original data in a buffer
or recovered from the medium). The valid data shall be placed in the reallocated logical block. The device server shall report any
failures that occur during the reallocation operation. Error reporting as specified by the error recovery bits (i.e., the EER bit, the PER
bit, the DTE bit, and the DCR bit) shall be performed only after completion of the reallocation. See the REASSIGN BLOCKS command (see 3.29) for error procedures.

ARRE (Automatic Read Reallocation Enabled) bit
0

An automatic read reallocation enabled (ARRE) bit set to zero specifies that the device server shall not perform automatic reallocation of defective logical blocks during read operations.

1

An ARRE bit set to one specifies that the device server shall enable automatic reallocation of defective logical blocks during read
operations. All error recovery actions required by the error recovery bits (i.e., the EER bit, the PER bit, the DTE bit, and the DCR bit)
shall be processed. The automatic reallocation shall then be performed only if the device server successfully recovers the data. The
recovered data shall be placed in the reallocated logical block. The device server shall report any failures that occur during the reallocation operation. Error reporting as specified by the error recovery bits (i.e., the EER bit, the PER bit, the DTE bit, and the DCR
bit) shall be performed only after completion of the reallocation operation. See the REASSIGN BLOCKS command (see 3.29) for
error procedures.

TB (Transfer Block) bit
0

A transfer block (TB) bit set to zero specifies that the device server shall not transfer a logical block to the data-in buffer if the logical
block is not recovered within the recovery limits specified.

1

A TB bit set to one specifies that the device server shall transfer a logical block to the data-in buffer before returning CHECK CONDITION status if the logical block is not recovered within the recovery limits specified. The data returned in this case is vendor-specific. The TB bit does not affect the action taken for recovered data.

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RC (Read Continuous) bit
0

A read continuous (RC) bit set to zero specifies that error recovery operations that cause delays are acceptable during the data
transfer. Data shall not be fabricated.

1

An RC bit set to one specifies the device server shall transfer the entire requested length of data without adding delays to perform
error recovery procedures. This implies that the device server may send data that is erroneous or fabricated in order to maintain a
continuous flow of data. The device server shall assign priority to the RC bit over conflicting bits within this byte.

Note.

Fabricated data may be data already in a buffer or any other vendor-specific data. The RC bit may be used in image processing, audio, or video applications.

EER (Enable Early Recovery) bit
1

An enable early recovery (EER) bit set to one specifies that the device server shall use the most expedient form of error recovery
first.

0

An EER bit set to zero specifies that the device server shall use an error recovery procedure that minimizes the risk of error misdetection or mis-correction. This bit only applies to data error recovery and it does not affect positioning retries.

PER (Post Error) bit
1

A post error (PER) bit set to one specifies that if a recovered read error occurs during a command performing a read or write operation, then the device server shall terminate the command with CHECK CONDITION status with the sense key set to RECOVERED ERROR. If the DTE bit is set to one, then the PER bit shall be set to one

0

A PER bit set to zero specifies that if a recovered read error occurs during a command performing a read or write operation, then
the device server shall perform error recovery procedures within the limits established by the error recovery parameters and only
terminate the command with CHECK CONDITION status if the error becomes uncorrectable based on the established limits.

DTE (Data Terminate On Error) bit
1

A data terminate on error (DTE) bit set to one specifies that the device server shall terminate the data-in or data-out buffer transfer
upon detection of a recovered error.

0

A DTE bit set to zero specifies that the device server shall not terminate the data-in or data-out buffer transfer upon detection of a
recovered error.

DCR (Disable Correction) bit
1

A disable correction (DCR) bit set to one specifies that ECC shall not be used for data error recovery.

0

A DCR bit set to zero allows the use of ECC for data error recovery. If the EER bit is set to one, the DCR bit shall be set to zero.

The combinations of the error recovery bits (i.e., the EER bit, the PER bit, the DTE bit, and the DCR bit) are explained in table 323.
Table 323
EER
0

PER
0

Combined error recovery bit descriptions (Sheet 1 of 3)
DTE
0

DCR Description
0
The device server shall perform the full number of retries as specified in the READ RETRY COUNT field for
read operations, the WRITE RETRY COUNT field for write operations, and the VERIFY RETRY COUNT field
(see 4.3.21) for verify operations and shall perform error correction in an attempt to recover the data.
The device server shall not report recovered errors. The device server shall terminate a command with
CHECK CONDITION status before the transfer count is exhausted only if an unrecoverable error is detected.

0

0

0

1

If an unrecoverable data error occurs during a read operation, the data in the block with the unrecoverable
error may or may not be transferred to the data-in buffer depending on the setting of the transfer block (TB)
bit.
The device server shall perform the full number of retries as specified in the READ RETRY COUNT field for
read operations, the WRITE RETRY COUNT field for write operations, and the VERIFY RETRY COUNT field
(see 4.3.21) for verify operations but shall not perform error correction in an attempt to recover the data.
The device server shall not report recovered errors. The device server shall terminate a command with
CHECK CONDITION status before the transfer count is exhausted only if an unrecoverable error is detected.
If an unrecoverable data error occurs during a read operation, the data in the block with the unrecoverable
error may or may not be transferred to the data-in buffer depending on the setting of the transfer block (TB)
bit.

0
0

0
0

1
1

0
1

Invalid mode. The PER bit shall be set to one if the DTE bit is set to one.
Invalid mode. The PER bit shall be set to one if the DTE bit is set to one.

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Table 323

Combined error recovery bit descriptions (Sheet 2 of 3)

EER

PER

DTE

0

1

0

DCR Description
0

The device server shall perform the full number of retries as specified in the READ RETRY COUNT field for
read operations, the WRITE RETRY COUNT field for write operations, and the VERIFY RETRY COUNT field
(see 4.3.21) for verify operations and shall perform error correction in an attempt to recover the data.
The device server shall terminate a command with CHECK CONDITION status before the transfer count is
exhausted only if an unrecoverable error is detected.
If an unrecovered read error occurs during a read operation, the transfer block (TB) bit determines whether
the data for the logical block with the unrecovered read error is transferred to the data-in buffer.

0

1

0

1

If a recovered error occurs while the device server is performing a read or write operation, then, after the
operation is complete, the device server shall terminate the command with CHECK CONDITION status with
the sense key set to RECOVERED ERROR. The INFORMATIO field in the sense data shall contain the LBA
of the last recovered error that occurred during the command.
The device server shall perform the full number of retries as specified in the READ RETRY COUNT field for
read operations, the WRITE RETRY COUNT field for write operations, and the VERIFY RETRY COUNT field
(see 4.3.21) for verify operations but shall not perform error correction in an attempt to recover the data.
The device server shall terminate a command performing a read or write operation with CHECK CONDITION
status before the transfer count is exhausted only if an unrecoverable error is detected.
If an unrecovered read error occurs during a read operation, the transfer block (TB) bit determines whether
the data for the logical block with the unrecovered read error is transferred to the data-in buffer.

0

1

1

0

If a recovered error occurs while the device server is performing a read or write operation, then, after the
operation is complete, the device server shall terminate the command with CHECK CONDITION status with
the sense key set to RECOVERED ERROR. The INFORMATION field in the sense data shall contain the LBA
of the last recovered error that occurred during the command.
The device server shall perform the full number of retries as specified in the READ RETRY COUNT field for
read operations, the WRITE RETRY COUNT field for write operations, and the VERIFY RETRY COUNT field
(see 4.3.21) for verify operations and shall perform error correction in an attempt to recover the data.
The device server shall terminate a command performing a read or write operation with CHECK CONDITION
status before the transfer count is exhausted if any error, either recoverable or unrecoverable, is detected.
The INFORMATION field in the sense data shall contain the LBA of the block in error.

0

1

1

1

If an unrecoverable data error occurs during a read operation, the transfer block (TB) bit determines whether
the data for the logical block with the unrecovered read error is transferred to the data-in buffer.
The device server shall perform the full number of retries as specified in the READ RETRY COUNT field for
read operations, the WRITE RETRY COUNT field for write operations, and the VERIFY RETRY COUNT field
(see 4.3.21) for verify operations but shall not perform error correction in an attempt to recover the data.
The device server shall terminate a command performing a read or write operation with CHECK CONDITION
status before the transfer count is exhausted if any error, either recoverable or unrecoverable, is detected.
The INFORMATION field in the sense data shall contain the LBA of the block in error.

1

0

0

0

If an unrecoverable data error occurs during a read operation, the transfer block (TB) bit determines whether
the data for the logical block with the unrecovered read error is transferred to the data-in buffer.
The device server shall perform the fewest possible number of retries and perform error correction in an
attempt to recover the data.
The device server shall not report recovered errors. The device server shall terminate a command performing a read or write operation with CHECK CONDITION status before the transfer count is exhausted only if
an unrecoverable error is detected.

1
1

0
1

0
0

1
0

If an unrecoverable data error occurs during a read operation, the transfer block (TB) bit determines whether
the data for the logical block with the unrecovered read error is transferred to the data-in buffer.
Invalid mode. The DCR bit shall be set to zero if the EER bit is set to one.
The device server shall perform the fewest possible number of retries and perform error correction in an
attempt to recover the data.
The device server shall terminate a command performing a read or write operation with CHECK CONDITION
status before the transfer count is exhausted only if an unrecoverable error is detected.
If an unrecoverable data error occurs during a read operation, the transfer block (TB) bit determines whether
the data for the logical block with the unrecovered read error is transferred to the data-in buffer

1

1

0

1

If a recovered error occurs while the device server is performing a read or write operation, then, after the
operation is complete, the device server shall terminate the command with CHECK CONDITION status with
the sense key set to RECOVERED ERROR. The INFORMATION field in the sense data shall contain the
LBA of the last recovered error that occurred during the command.
Invalid mode. The DCR bit shall be set to zero if the EER bit is set to one.

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Table 323
EER
1

PER
1

Combined error recovery bit descriptions (Sheet 3 of 3)
DTE
1

DCR Description
0
The device server shall perform the fewest possible number of retries and perform error correction in an
attempt to recover the data.
The device server shall terminate the command performing a read or write operation with CHECK CONDITION status before the transfer count is exhausted if any error, either recoverable or unrecoverable, is
detected. The INFORMATION field in the sense data shall contain the LBA of the block in error.

If an unrecoverable data error occurs during a read operation, the transfer block (TB) bit determines whether
the data for the logical block with the unrecovered read error is transferred to the data-in buffer.
1
1
1
1
Invalid mode. The DCR bit shall be set to zero if the EER bit is set to one.
If an invalid combination of the error recovery bits is sent by the application client the device server shall terminate the MODE SELECT
command with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID
FIELD IN PARAMETER LIST.
READ RETRY COUNT field
The READ RETRY COUNT field specifies the number of times that the device server shall attempt its recovery algorithm during read operations.
WRITE RETRY COUNT field
The WRITE RETRY COUNT field specifies the number of times that the device server shall attempt its recovery algorithm during write
operations.
RECOVERY TIME LIMIT field
The RECOVERY TIME LIMIT field specifies in milliseconds the maximum time duration that the device server shall use for data error
recovery procedures. The device server may round this value as described in 2.3. The limit in this field specifies the maximum error recovery time allowed for any individual command. A RECOVERY TIME LIMIT field set to zero specifies that the device server shall use its
default value.
When both a retry count and a recovery time limit are specified, the field that specifies the recovery action of least duration shall have
priority.
To disable all types of correction and retries the application client should set the EER bit to zero, the PER bit to one, the DTE bit to one, the
DCR bit to one, the READ RETRY COUNT field to 00h, the WRITE RETRY COUNT field to 00h, and the RECOVERY TIME LIMIT field to
0000h.

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4.3.17

Protocol Specific Logical Unit mode page (18h)

4.3.17.1

Protocol specific parameters

4.3.17.1.1

Protocol specific parameters introduction

Some commands use protocol specific information in their CDBs or parameter lists. This subclause describes those protocol specific
parameters.
The Protocol Specific Logical Unit mode page (see table 324) provides protocol specific controls that are associated with a logical unit.
For Parallel SCSI, see 4.3.17.
For Fibre Channel (FC), see 4.3.17.2.
For Serial Attached SCSI (SAS), see 4.3.17.3.
Table 324

Protocol Specific Logical Unit mode page

Bit
Byte

7

6

5

0

PS

SPF (0b)

4

3

2

1

0

PAGE CODE (18h)
PAGE LENGTH (n-1)

1
Reserved

2

PROTOCOL IDENTIFIER

3
PROTOCOL SPECIFIC MODE PARAMETERS

...
n

During an I_T_L nexus, the Protocol Specific Logical Unit mode page controls parameters that affect both:
a) One or more target ports; and
b) The logical unit.
The parameters that may be implemented are specified in the SCSI transport protocol standard for the target port. The mode page policy
(see 4.4.12) for this mode page shall be shared or per target port and should be per target port.
The parameters for a target port and logical unit affect their behavior regardless of which initiator port is forming an I_T_L nexus with the
target port and logical unit. If a parameter value is changed, the device server shall establish a unit attention condition for the initiator port
associated with every I_T nexus except the I_T nexus on which the MODE SELECT command was received, with the additional sense
code set to MODE PARAMETERS CHANGED.
PS bit, SPF bit, PAGE CODE field, and PAGE LENGTH field
The PS bit, SPF bit, PAGE CODE field, and PAGE LENGTH field are described in 4.3.5.

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PROTOCOL IDENTIFIER field
The value in the PROTOCOL IDENTIFIER (see table 325) field defines the SCSI transport protocol to which the mode page applies. For a
MODE SENSE command (see 3.11), the device server shall set the PROTOCOL IDENTIFIER field to one of the values shown in Table
325 to indicate the SCSI transport protocol used by the target port through which the MODE SENSE command is being processed. For a
MODE SELECT command (see 3.9), the application client shall set the PROTOCOL IDENTIFIER field to one of the values shown in Table
325 indicating the SCSI transport protocol to which the PROTOCOL SPECIFIC MODE PARAMETERS apply. If a device server receives a
mode page containing a transport protocol identifier value other than the one used by the target port on which the MODE SELECT command was received, then the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL
REQUEST, and the additional sense code set to INVALID FIELD IN PARAMETER LIST.
PROTOCOL SPECIFIC PARAMETERS
The PROTOCOL SPECIFIC PARAMETERS may include a PROTOCOL IDENTIFIER field (see table 325) as a reference for the SCSI
transport protocol to which the protocol specific parameter applies.
Table 325
Protocol
Identifier

PROTOCOL IDENTIFIER values
Description

Protocol
Standard

0h

Fibre Channel

FCP

1h

Parallel SCSI

SPI-5

2h

SSA

3h

IEEE 1394

4h

SCSI Remote Direct Memory Access Protocol

SRP

5h

Internet SCSI (iSCSI)

iSCSI

6h

SAS Serial SCSI Protocol

SPL-3

7h

Automation/Drive Interface Transport Protocol

ADT-2

8h

AT Attachment Interface (ATA/ATAPI)

ACS-2

9h

USB Attached SCSI

UAS-2

Ah

SCSI over PCIe

Bh - Eh
Fh

SSA-S3P
SBP-3

SOP

Reserved
No specific protocol

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4.3.17.2

Fibre Channel Logical Unit Control mode page (18h)

The Fibre Channel Logical Unit Control mode page (see table 326) contains those parameters that select FCP logical unit operation
options. The implementation of any parameter and its associated functions is optional. The mode page follows the MODE SENSE and
MODE SELECT command rules.
Table 326

Fibre Channel Logical Unit Control mode page (18h)

Bit
Byte

7

6

5

0

PS

SPF (0B)

4

3

2

1

0

PAGE CODE (18h)
PAGE LENGTH (06h)

1
Reserved

2

PROTOCOL IDENTIFIER (FCP = 0h)
Reserved

3
4

Reserved

5

Reserved

6

Reserved

7

Reserved

EPDC

The PS bit, SPF bit, PAGE CODE field and PAGE LENGTH field are described in 4.3.5.
PROTOCOL IDENTIFIER field
The value in the PROTOCOL IDENTIFIER (see table 325) field defines the SCSI transport protocol to which the mode page applies. For a
MODE SENSE command (see 3.11), the device server shall set the PROTOCOL IDENTIFIER field to one of the values shown in Table
325 to indicate the SCSI transport protocol used by the target port through which the MODE SENSE command is being processed. For a
MODE SELECT command (see 3.9), the application client shall set the PROTOCOL IDENTIFIER field to one of the values shown in Table
325 indicating the SCSI transport protocol to which the PROTOCOL SPECIFIC MODE PARAMETERS apply. If a device server receives a
mode page containing a transport protocol identifier value other than the one used by the target port on which the MODE SELECT command was received, then the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL
REQUEST, and the additional sense code set to INVALID FIELD IN PARAMETER LIST.
EPDC (ENABLE PRECISE DELIVERY CHECKING) bit
1

An ENABLE PRECISE DELIVERY CHECKING (EPDC) bit of one indicates that the logical unit shall use the precise delivery function (see FCP-4).

0

When the EPDC bit is set to zero, the logical unit shall not use the precise delivery function and shall ignore the contents of the
CRN field in the FCP_CMND IU.

The EPDC bit is valid for all types of link connections. If the precise delivery function is not supported and the Fibre Channel Logical Unit
Control mode page is supported by the logical unit, the EPDC bit shall be masked as not changeable and shall follow the MODE SENSE
and MODE SELECT command rules (see 3.9).
If the Fibre Channel Logical Unit Control mode page is not supported by a logical unit, the initiator shall assume that the precise delivery
function is not supported by that logical unit.

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4.3.17.3

SAS Protocol-Specific Logical Unit mode page

The SAS Protocol-Specific Logical Unit mode page (see SPL-2) contains parameters that affect SSP target port operation on behalf of the
logical unit.
Table 327 defines the subpages of this mode page.
Table 327

SAS Protocol-Specific Logical Unit mode page subpages

Subpage

Description

Reference

Short page

Short format

4.3.17.3.1

Long page 00h

Not allowed

Long page E0h - FEh

Vendor specific

Long page FFh

Return all subpages for the Protocol-Specific Logical Unit mode page SPC-4

All others

Reserved

4.3.17.3.1

Protocol-Specific Logical Unit mode page - short format (18h)

The mode page policy (see 4.4.12) for the Protocol-Specific Logical Unit mode page short format subpage shall be either shared or per
target port. If a SAS target device has multiple SSP target ports, the mode page policy should be per target port. Parameters in this page
shall affect all phys in the SSP target port if the mode page policy is per target port, and shall affect all SSP target ports in the SAS target
device if the mode page policy is shared.
Table 328 defines the format of the page for SAS SSP.
Table 328
Bit
Byte
0
1
2

Protocol-Specific Logical Unit mode page for SAS SSP - short format
7

6

PS

SPF (0b)

Reserved

3
4
...
7

5

4

3

2

1

0

PAGE CODE (18h)
PAGE LENGTH (06h)
TRANSPORT
LAYER
PROTOCOL IDENTIFIER (6h)
RETRIES
Reserved
Reserved

The PARAMETERS SAVEABLE (PS) bit is defined in 4.3.5.
The SPF bit shall be set to zero for access to the short format mode page.
The PAGE CODE field shall be set to 18h.
The PAGE LENGTH field shall be set to 06h.
The PROTOCOL IDENTIFIER field shall be set to 6h indicating this is a SAS SSP specific mode page.
TRANSPORT LAYER RETRIES bit
1

A TRANSPORT LAYER RETRIES bit set to one specifies that the target port shall support transport layer retries for XFER_RDY
and DATA frames for the logical unit as described in SAS-3 Transport Layer.

0

A TRANSPORT LAYER RETRIES bit set to zero specifies that transport layer retries shall not be used.

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4.3.18

Protocol Specific Port mode page (19h)

The Protocol Specific Port mode page provides protocol specific controls that are associated with a SCSI port. The page_0 format (see
table 329) is used for subpage 00h and SUB_PAGE format (see table 330) is used for subpages 01h through FEh. See the SCSI transport
protocol standard for definition of the PROTOCOL SPECIFIC MODE PARAMETERS.
Table 329
Bit
Byte
0
1
2
3
...
n
Table 330
Bit
Byte
0
1
2
3
4
5
6
...
n

Page_0 format Protocol Specific Port mode page
7

6

5

PS

SPF (0b)

4

3

2

1

0

PAGE CODE (19h)
PAGE LENGTH (n-1)
PROTOCOL IDENTIFIER

Reserved

PROTOCOL SPECIFIC MODE PARAMETERS

Sub_page format Protocol Specific Port mode page
7

6

5

PS

SPF (1b)

4

3

2

1

0

PAGE CODE (19h)
SUBPAGE CODE

(MSB)

PAGE LENGTH (n-3)

(LSB)

Reserved
Reserved

PROTOCOL IDENTIFIER
PROTOCOL SPECIFIC MODE PARAMETERS

The Protocol Specific Port mode page controls parameters that affect one or more target ports. The parameters that may be implemented
are specified in the SCSI transport protocol standard for the target port. The mode page policy (see 4.4.12) for this mode page shall be
shared or per target port. If the SCSI target device contains more than one target port, the mode page policy should be per target port.
The parameters for a target port affect its behavior regardless of which initiator port is forming an I_T nexus with the target port. The
parameters may be accessed by MODE SENSE (see 3.11) and MODE SELECT (see 3.9) commands directed to any logical unit
accessible through the target port. If a parameter value is changed, the device server for all logical units accessible through the target port
shall establish a unit attention condition for the initiator port associated with every I_T nexus except the I_T nexus on which the MODE
SELECT command was received, with the additional sense code set to MODE PARAMETERS CHANGED.
PS bit, SPF bit, PAGE CODE field, SUBPAGE CODE field, and PAGE LENGTH field
The PS bit, SPF bit, PAGE CODE field, SUBPAGE CODE field, and PAGE LENGTH field are described in 4.3.5.
PROTOCOL IDENTIFIER field and PROTOCOL SPECIFIC MODE PARAMETERS
The value in the PROTOCOL IDENTIFIER field (see 4.3.17.1.1) defines the SCSI transport protocol to which the mode page applies. For
a MODE SENSE command, the device server shall set the PROTOCOL IDENTIFIER field to one of the values shown in table 325 to indicate the SCSI transport protocol used by the target port through which the MODE SENSE command is being processed. For a MODE
SELECT command, the application client shall set the PROTOCOL IDENTIFIER field to one of the values shown in table 325 indicating the
SCSI transport protocol to which the PROTOCOL SPECIFIC MODE PARAMETERS apply. If a device server receives a mode page containing a transport protocol identifier value other than the one used by the target port on which the MODE SELECT command was
received, then command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the
additional sense code set to INVALID FIELD IN PARAMETER LIST.
For Parallel SCSI, see 4.3.18.1.
For Fibre Channel (FC), see 4.3.18.2.
For Serial Attached SCSI (SAS), see 4.3.18.3.

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4.3.18.1

Port Control Mode page (19h) for Parallel SCSI

The Port Control Mode page contains the parameters that affect SCSI target port operation options. The page shall be implemented by
LUN 0 of all SPI SCSI target devices. The page shall not be implemented by logical units other than LUN 0. The implementation of any bit
and its associated functions is optional. The page follows the MODE SENSE/MODE SELECT rules specified by the ANSI SPC-4 standard.
Each SCSI target port shall maintain an independent set of port control mode page parameters for each SCSI initiator port. The
parameters saveable bit in the mode page format header returned with MODE SENSE command shall be set to zero if the long mode page
format is being used (i.e., Long bit set to one), indicating the parameters are not saved through resets.
After a MODE SELECT command, parameter settings shall remain in effect until either:
(a)

settings are changed by another MODE SELECT command,

(b)

a logical unit reset of LUN 0 occurs,

(c)

an SDTR negotiation successfully completes,

(d)

a WDTR negotiation successfully completes, or

(e)

a PPR negotiation successfully completes with the HOLD_MCS bit set to zero.

Table 331

Port Control Mode page short format (19h)

Bit
Byte

7

6

5

0

PS

Long (0)

3

2

1

0

PAGE CODE (19h)
PAGE LENGTH (06h)

1
Reserved

2

PROTOCOL IDENTIFIER (1h)
Reserved

3
4

4

(MSB)

SYNCHRONOUS TRANSFER TIMEOUT

5
6

Reserved

7

Reserved

(LSB)

PS (Parameter Savable) bit
The Parameter Savable (PS) bit of 0 indicates that the page 19h parameter data is not savable in non-volatile memory.
Long bit
The Long bit shall be set zero, indicating the parameters are saved through resets.
PAGE CODE field and PAGE LENGTH field
The PAGE CODE field and PAGE LENGTH field are described in 4.2.2.
PROTOCOL IDENTIFIER field
The PROTOCOL IDENTIFIER field value of 1h indicates that this mode page applies to a SPI SCSI device. See the SPC-4 standard for
other port control page protocol identifiers.
SYNCHRONOUS TRANSFER TIMEOUT field
The SYNCHRONOUS TRANSFER TIMEOUT field indicates the maximum amount of time in 1 ms increments that the SCSI target port
shall wait before generating an error by doing an unexpected bus free. The SCSI target port shall only go to a BUS FREE phase if one of
the following events causes the timer, once started, to not reset or reload before expiring.
a) If there is a REQ transition when there are no outstanding REQs waiting for an ACK then load and start the timer.
b) If there is a REQ transition when there are any outstanding REQs waiting for an ACK then there is no effect on the timer.
c) If there is an ACK transition when there are outstanding REQs waiting for an ACK then load and start the timer.
d) If, after an ACT transition, there are no outstanding REQs waiting for an ACK then stop the timer.
A SYNCHRONOUS TRANSFER TIMEOUT field value of 0000h indicates that the function is disabled.
A value of FFFFh indicates an unlimited period.
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Table 332

Port Control Mode page long format (19h)

Bit
Byte

7

6

5

0

PS

Long (1)

3

2

1

0

PAGE CODE (19h)
SUBPAGE CODE

1
2

4

(MSB)

PAGE LENGTH (n – 3)

(LSB)

3
Reserved

4
Reserved

5

PROTOCOL IDENTIFIER = 1h

6
PROTOCOL-SPECIFIC MODE PARAMETERS

...
n
PS bit

The Parameter Savable (PS) bit of 0 indicates that the page 19h parameter data is not savable in non-volatile memory.
Long bit
The Long bit shall be set one, indicating the parameters are not saved through resets.
PAGE CODE field and PAGE LENGTH field
The PAGE CODE field and PAGE LENGTH field are described in 4.2.2.
SUBPAGE CODE field
The SUBPAGE CODE field indicates which subpage is being accessed as listed in Table 333. If the SUBPAGE CODE field is zero, the
SCSI target device shall return a CHECK CONDITION status. The sense key shall be set to ILLEGAL REQUEST and the additional sense
code set to ILLEGAL FIELD IN PARAMETER LIST.
Table 333

Subpage Code field values

Subpage
Code

Description

Reference
clause

1

Margin control subpage

4.3.18.1.1

2

Saved training configuration values subpage

4.3.18.1.2

3

Negotiated settings subpage

4.3.18.1.3

4

Report transfer capabilities subpage

4.3.18.1.4

PROTOCOL IDENTIFIER field and PROTOCOL SPECIFIC MODE PARAMETERS
The value in the PROTOCOL IDENTIFIER field (see 4.3.17.1.1) defines the SCSI transport protocol to which the mode page applies. For
a MODE SENSE command, the device server shall set the PROTOCOL IDENTIFIER field to one of the values shown in table 332 to indicate the SCSI transport protocol used by the target port through which the MODE SENSE command is being processed. For a MODE
SELECT command, the application client shall set the PROTOCOL IDENTIFIER field to one of the values shown in table 332 indicating the
SCSI transport protocol to which the PROTOCOL SPECIFIC MODE PARAMETERS apply. If a device server receives a mode page containing a transport protocol identifier value other than the one used by the target port on which the MODE SELECT command was
received, then command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL REQUEST, and the
additional sense code set to INVALID FIELD IN PARAMETER LIST.
For Parallel SCSI, see 4.3.18.1.
For Fibre Channel (FC), see 4.3.18.2.
For Serial Attached SCSI (SAS), see 4.3.18.3.

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4.3.18.1.1

Margin control subpage

The margin control subpage contains parameters that set and report margin control values for usage between the SCSI initiator/target port
pair on subsequent synchronous and paced transfers.
A MODE SENSE command shall return the current settings for the SCSI initiator/target port pair. Fields that are not implemented shall be
reported as zero.
Note.

The default value of each margin control field should be 0000b.

The margin control fields indicate absolute conditions centered around their default values. Absolute conditions means that the previous
history of the parameter has no relevance to the value of the parameter.
The maximum supported setting for each field is 0111b and the minimum supported setting for each field is 1000b. Up to 16 distinct values
are available for each field, representing monotonically changing device response. Devices that support fewer than 16 distinct values for a
field should round non-supported settings to a supported value.
The actual response of a SCSI device to a field value is vendor-specific and calibration of the actual minimum and maximum responses to
different field values is not defined in this manual or the ANSI SPI-4 specification. Margin control settings should not cause the driver to
violate SPI-4 specification electrical limits. Margin control settings should affect only the REQUEST, ACKNOWLEDGE, DATA BUS,
P_CRCA, and DB(P1) signals and should affect all of these signals driven by the device by the same amount.
The margin control fields contain two’s complement values as shown in the table below.
Table 334

Summary of margin control field values
Value
Parameter values

Binary

Decimal

0111b

7

0110b

6

0101b

5

0100b

4

0011b

3

0010b

2

0001b

1

000b

0

111b

–1

1110b

–2

1101b

–3

1100b

–4

1011b

–5

1010b

–6

1001b

–7

1000b

–8

Maximum setting

Recommended default value

Minimum setting

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Table 335
Bit
Byte

Margin control subpage
7

6

5

4

3

2

1

0

Reserved

0
1

DRIVER STRENGTH

Reserved

2

DRIVER ASYMMETRY

DRIVER PRECOMPENSATION

3

DRIVER SLEW RATE

Reserved

4

Reserved

5

Reserved

6

Reserved

7

VENDOR-SPECIFIC

8
...

Reserved

15
DRIVER STRENGTH field
The DRIVER STRENGTH field indicates the relative amount of driver source current used by the driver (see clause 7.3.2 in the ANSI SPI4 specification). The DRIVER STRENGTH field affect both the strong and weak drivers. A larger value indicates more driver source current.
DRIVER ASYMMETRY field
The DRIVER ASYMMETRY field indicates the relative difference between the amplitudes of asserted and negated signals launched from
the driver. A larger value indicates a relatively stronger asserted signal compared to the negated signal.
DRIVER PRECOMPENSATION field
The DRIVER PRECOMPENSATION field indicates the relative difference between the weak driver and the strong driver amplitudes when
pre-compensation is enabled. A larger value indicates a larger difference between the weak and strong amplitudes.
DRIVER SLEW RATE field
The DRIVER SLEW RATE field indicates the relative difference between the assertion and negation magnitudes divided by the rise or fall
time. A larger value indicates a faster slew rate.

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4.3.18.1.2

Saved training configuration values subpage

The saved training configuration values subpage is used to report the SCSI device’s saved training configuration values. These vendorspecific values are maintained by the SCSI device when the retain training information option is enabled. The fields are listed in Table
however the content of the field is vendor-specific.
Only values for the current I_T nexus are reported.
Table 336
Bit
Byte

Saved training configuration values subpage
7

6

5

4

3

2

1

0

0
Reserved

...
3
4

MSB
DB(0) Value

...

LSB

7
...
64

...
MSB
DB(15) Value

...

LSB

67
68

MSB
P_CRCA Value

...

LSB

71
72

MSB
P1 Value

...

LSB

75
76

MSB
BSY Value

...

LSB

79
80

MSB
SEL Value

...

LSB

83
84

MSB
RST Value

...

LSB

87
88

MSB
REQ Value

...

LSB

91
92

MSB
ACK Value

...

LSB

95
96

MSB
ATN Value

...

LSB

99
100

MSB
C/D Value

...

LSB

103
104

MSB

...
107
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LSB
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Table 336

Saved training configuration values subpage

Bit
Byte

7

108

MSB

6

5

4

3

2

1

0

MSG Value

...

LSB

111
112
Reserved

...
127
4.3.18.1.3

Negotiated settings subpage

The negotiated setting subpage is used to report the negotiated settings of a SCSI target port for the current I_T nexus.
Table 337
Bit
Byte

Negotiated settings subpage
7

6

5

4

3

2

0

SENT PCOMP_EN

RECEIVED
PCOM_EN

TRANSFER PERIOD FACTOR

0
1

Reserved

2

REQ/ACK OFFSET

3

TRANSFER WIDTH EXPONENT

4

1

Reserved

5

PROTOCOL OPTIONS BITS
Reserved

TRANSCEIVER MODE

6

Reserved

7

Reserved

TRANSFER PERIOD FACTOR field
The TRANSFER PERIOD FACTOR field indicates the negotiated transfer period factor for the current I_T nexus.
REQ/ACK OFFSET field
The REQ/ACK OFFSET field indicates the negotiated REQ/ACK offset for the current I_T nexus.
TRANSFER WIDTH EXPONENT field
The TRANSFER WIDTH EXPONENT field indicates the negotiated transfer width exponent for the current I_T nexus.
PROTOCOL OPTIONS BITS field
The PROTOCOL OPTIONS BITS field contains the negotiated protocol options for the current I_T nexus.
TRANSCEIVER MODE field
The TRANSCEIVER MODE field specifies the current bus mode of the SCSI target port as defined below.
Code

Bus mode

00b

Unknown (e.g., device not capable of reporting bus mode)

01b

Single-ended

10b

Low Voltage Differential

11b

High Voltage Differential

SENT PCOMP_EN bit
The SENT PCOMP_EN bit contains the value of the PCOMP_EN bit sent by the SCSI target port for the current I_T nexus.
RECEIVED PCOMP_EN bit
The RECEIVED PCOMP_EN bit contains the value of the PCOMP_EN bit received by the SCSI target port for the current I_T nexus.
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4.3.18.1.4

Report transfer capabilities subpage

The Report transfer capabilities subpage is used to report the transfer capabilities for the SCSI target port. The values in this subpage are
not changeable via a MODE SELECT command.
Table 338
Bit
Byte

Report transfer capabilities subpage
7

6

5

4

3

2

0

MINIMUM TRANSFER PERIOD FACTOR

1

Reserved

2

MAXIMUM REQ/ACK OFFSET

3

MAXIMUM TRANSFER WIDTH EXPONENT

4

PROTOCOL OPTIONS BITS SUPPORTED

5

Reserved

6

Reserved

7

Reserved

1

0

MINIMUM TRANSFER PERIOD FACTOR byte
The MINIMUM TRANSFER PERIOD FACTOR field shall be set to the smallest value of the transfer period factor supported by the SCSI
target port.
MAXIMUM REQ/ACK OFFSET byte
The MAXIMUM REQ/ACK OFFSET shall be set to the largest value of the REQ/ACK offset supported by the SCSI target port.
MAXIMUM TRANSFER WIDTH EXPONENT byte
The MAXIMUM TRANSFER WIDTH EXPONENT field shall be set to the largest value of the transfer width exponent supported by the
SCSI target port.
PROTOCOL OPTIONS BITS SUPPORTED byte
The SCSI target port shall set the bits in the PROTOCOL OPTIONS BITS SUPPORTED field to indicate the protocol options supported by
the SCSI target port.

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4.3.18.2

Port Control Mode page (19h) for Fibre Channel (FC)

The Fibre Channel Interface Control page controls options relevant to Fibre Channel protocol. It is intended for the control of features
unique to Fibre Channel protocol that are not suitable for control by login or other techniques defined for Fibre Channel.
Both the current and saved values of Mode page 19h, byte 3, are changeable using the Mode Select command. When the saved value of
Byte 3 is changed, a new value is stored in nonvolatile (flash) memory, not on disk, and is reported during a Mode Sense command when
either the current or saved value is requested.
The current value of Byte 3 may be modified using Mode Select command any number of times. The saved value of Byte 3 may be
modified using the Mode Select command up to 32 times. After 32 modifications, additional attempts to modify will result in a response of
Illegal Request (05) with Error Code of 2600 (Invalid field in parameter list) and the Sense Key pointing to byte 3 as the offending
parameter. Additional updates of Byte 3 saved value may be accomplished by downloading new microcode that supports Fibre Channel
Interface Control page 19h. After a download, the saved value of Byte 3 may be updated 31 more times or 32 times if the value is 0 at the
time of download.
The saved and current value of Byte 3 is preserved through the download.
Table 339

Fibre Channel Interface Control page (19h)

Bit
Byte

7

6

5

0

PS

SPF (0b)

4

3

2

1

0

PAGE CODE (19h)
PAGE LENGTH (06h)

1
Reserved

2
DTFD

3

PLPB

DDIS

PROTOCOL IDENTIFIER (FCP = 0h)
DLM

RHA

4

Reserved

5

Reserved

ALWLI

DTIPE

DTOLI

Reserved

6

SEQUENCE INITIATIVE RESOURCE RECOVERY TIMEOUT VALUE (RR_TOVSEQ_INIT)

7

PS (Parameter Savable)
The PS bit is defined in 4.3.5.
SPF bit
The SPF field shall be set to zero for access to the short format mode page.
PAGE CODE field
The PAGE CODE field is described in 4.2.2.
Page Length byte
The length of the Fibre Channel Interface Control page in bytes (06h). If the allocation length is too small to transfer all of the page, the
page length is not adjusted to reflect the truncation.
PROTOCOL IDENTIFIER field
The value in the PROTOCOL IDENTIFIER (see table 339) field defines the SCSI transport protocol to which the mode page applies. For a
MODE SENSE command (see 3.11), the device server shall set the PROTOCOL IDENTIFIER field to one of the values shown in Table
339 to indicate the SCSI transport protocol used by the target port through which the MODE SENSE command is being processed. For a
MODE SELECT command (see 3.9), the application client shall set the PROTOCOL IDENTIFIER field to one of the values shown in Table
339 indicating the SCSI transport protocol to which the PROTOCOL SPECIFIC MODE PARAMETERS apply. If a device server receives a
mode page containing a transport protocol identifier value other than the one used by the target port on which the MODE SELECT command was received, then the command shall be terminated with CHECK CONDITION status, with the sense key set to ILLEGAL
REQUEST, and the additional sense code set to INVALID FIELD IN PARAMETER LIST.
DTFD (Disable Target Fabric Discovery)
1

The target attached by an FC-AL loop will not recognize the presence of a fabric loop port (FL_Port) on the loop. The target will only

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perform the private loop functions defined for FC-PLDA targets.
The target attached by an FC-AL loop will discover the FL_Port if present on the loop and will perform the public loop functions
defined for FC-FLA targets. Targets attached to an N_Port or to an F_Port will ignore this bit.

0

PLPB (Prevent Loop Port Bypass)
The target ignores any Loop Port Bypass (LPB) and Loop Port Enable (LPE) primitive sequences. The loop port remains enabled.

1
Note.

0

Do not set the PLPB bit to one (1) and the DTIPE bit to one (1) at the same time as this is an illegal bit combination. When an illegal bit combination is sent by the application client, the device server returns Check Condition status and sets the sense key to
Illegal Request with the additional sense code set to Invalid Field in the Parameter List.
The target allows the Loop Port Bypass and Port Bypass Enable primitive sequences to control the port bypass circuit.

DDIS (Disable Discovery)
1

The target does not require receipt of Address or Port Discovery ELS following loop initialization. The target resumes processing of
tasks upon completion of loop initialization.

0

The target must wait to receive an Address or Port Discovery ELS before it resumes processing tasks for that initiator.

DLM (Disable Loop Master)
1

Indicates that a target attached to an FC-AL-2 loop shall not participate in loop master arbitration and shall not become loop master.
The target shall only repeat LISM frames it receives.

0

The target may participate in loop master arbitration in the normal manner and, if successful, may become loop master during the
loop initialization process. Targets not attached to an arbitrated loop shall ignore the DLM bit.

REQUIRE HARD ADDRESS (RHA) bit - formerly DSA bit
1

If the REQUIRE HARD ADDRESS (RHA) bit is set to one, a target FCP_Port attached to an arbitrated loop (see FCAL-2) shall only
attempt to obtain its hard address available in the SCA-2 connector (see SFF-8067) or device address jumpers during loop initialization.
The target FCP_Port shall not attempt to obtain an address during the LISA phase of initialization (see FC-AL-2). If there is a conflict
for the hard address selection during loop initialization or the target FCP_Port does not have a valid hard address available, the target
FCP_Port shall enter the nonparticipating state. If the target FCP_Port detects loop initialization while in the nonparticipating state, the
target FCP_Port shall again attempt to get its hard address. If the hard address has not changed from the address obtained in a previous successful loop initialization, the target FCP_Port shall attempt to obtain the address in the LIFA phase if a valid Fabric Login
exists or LIPA phase of loop initialization. If the hard address has changed, the target FCP_Port shall attempt to obtain the new
address in the LIHA phase.

0

If the RHA bit is set to zero, the target FCP_Port follows the normal initialization procedure, including the possibility of obtaining a
soft address during the loop initialization process.

Target FCP_Ports not attached to an arbitrated loop shall ignore the RHA bit.
DSA (Disable Soft Address)
1

The target does not select a soft address if there is a conflict for the Select_ID address available in the SCA connector during loop
initialization. If there is a Select_ID address conflict, the target enters the non-participation state. If the target detects loop initialization while in the non-participation state, the target again attempts to get the Select_ID address.

0

The target attempts to obtain a soft address during loop initialization if the Select_ID address is not available or if the Select_ID
address indicates the use of a soft address (7Fh).

If ESI activity is underway when the request for the hard address is received, the drive shall use the last known value of the hard address
before the current ESI activity started.

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ALWLI (Allow Login Without Loop Initialization)
1

The target uses the Select_ID address available in the SCA connector and accepts logins without verifying the address with loop
initialization.

0

The target must verify the address through loop initialization before accepting a login.

DTIPE (Disable Target Initiated Port Enable)
The target waits for an initiator to send the Loop Port Enable primitive before inserting itself into the loop. The target uses the
Select_ID address available in the SCA connector to determine if primitives are addressed to it.

1
Note.

Do not set the PLPB bit to one (1) and the DTIPE bit to one (1) at the same time as this is an illegal bit combination. When an
illegal bit combination is sent by the application client, the device server returns Check Condition status and sets the sense
key to Illegal Request with the additional sense code set to Invalid Field in the Parameter List.
After completing self test, the target enables the port in the loop without waiting for a Loop Port Enable primitive.

0

DTOLI (Disable Target Originated Loop Initialization)
1

The target does not originate the initializing LIP following insertion into the loop. The target responds to an Initializing LIP when it is
received. The target originates the Loop Failure LIP if it detects loop failure at its input. The target originates the Initializing LIP
when the loop failure is corrected.

0

After completing self test, the target originates the Initializing LIP when it enables a port in a loop.

SEQUENCE INITIATIVE RESOURCE RECOVERY TIMEOUT VALUE (RR_TOVSEQ_INIT) field
The RR_TOVSEQ_INIT timer (see FCP-4) is defined by the RR_TOVSEQ_INIT field and the RR_TOV UNITS field.
The RR_TOV UNITS field indicates the units for the RR_TOVSEQ_INIT field value, according to Table 340.
Table 340

Values for RR_TOV UNITS

Byte 6

Units of measure for
RR_TOVSEQ_INIT

bit 2

bit 1

bit 0

0

0

0

No timer is specified

0

0

1

0.001 s

0

1

1

0.1 s

1

0

1

10 s

All other values

Reserved

The RR_TOVSEQ_INIT field indicates the number of time units specified by the RR_TOV UNITS field that shall be used by the timer that
performs the RR_TOVSEQ_INIT timeout function. If no timer is specified, the RR_TOVSEQ_INIT value shall be ignored by the device server
and a vendor specific default value shall be used for RR_TOVSEQ_INIT.

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4.3.18.3

Protocol Specific Port Mode page (19h) for Serial Attached SCSI (SAS)

4.3.18.3.1

Protocol-specific Port mode page overview

The Protocol-Specific mode page (see 4.3.18) contains parameters that affect SSP target port operation. If the mode page is implemented,
all logical units in SCSI target devices in SAS domains supporting the MODE SELECT or MODE SENSE commands shall implement the
page.
If a SAS target device has multiple SSP target ports, changes in the short page parameters for one SSP target port should not affect other
SSP target ports.
Table 341 defines the subpages of this mode page.
Table 341

Protocol-Specific Port mode page subpages

Subpage

Description

Reference

Short format

4.3.18.3.2 and 4.3.18.3.3

Long page 01h

Phy Control and Discover subpage

4.3.18.3.4

Long page 02h

Port Control subpage

4.3.18.3.5

Long page 03h

Enhanced Phy Control subpage

4.3.18.3.6

Long page E5h

Transceiver Control (Out) subpage

4.3.18.3.7

Long page E6h

Transceiver Control (In) subpage

4.3.18.3.8

Long page FFh

Return all subpages for the Protocol-Specific
Port mode page

SPC-4

Short page

All others

Reserved

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4.3.18.3.2

Protocol-Specific Port mode page - short format - SAS-1.1

This clause describes the Protocol-Specific Port mode page implemented by products that are SAS-1.1 compliant. The mode page policy
(see 4.4.12) for the Protocol-Specific mode page short format subpage shall be either shared or per target port. If a SAS target device has
multiple SSP target ports, the mode page policy should be per target port.
Parameters in this page shall affect all phys in the SSP target port if the mode page policy is per target port, and shall affect all SSP target
ports in the SAS target device if the mode page policy is shared.
Table 342 defines the format of the page for SAS SSP.
Table 342

Protocol-Specific Port mode page for SAS SSP - short format - SAS-1.1

Bit
Byte

7

6

0

PS

SPF (0b)

5

4

2

1

Reserved

2

PAGE CODE (19h)

READY
LED
MEANING

PROTOCOL IDENTIFIER (6h)

Reserved

3
(MSB)

I_T NEXUS LOSS TIME
(LSB)

5
6

0

PAGE LENGTH (06h)

1

4

3

(MSB)

INITIATOR RESPONSE TIMEOUT

7

(LSB)

The PARAMETERS SAVEABLE (PS) bit is defined in 4.3.5.
The SPF field shall be set to zero for access to the short format mode page.
The PAGE CODE field shall be set to 19h.
The PAGE LENGTH field shall be set to 06h.
READY LED MEANING bit
The READY LED MEANING bit specifies the READY LED signal behavior (see SAS-3). Regardless of the mode page policy (see 4.4.12)
for this mode page, the shared mode page policy shall be applied to the READY LED MEANING bit.
PROTOCOL IDENTIFIER field
The PROTOCOL IDENTIFIER field shall be set to 6h indicating this is a SAS SSP specific mode page.

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I_T NEXUS LOSS TIME field
The I_T NEXUS LOSS TIME field contains the time that the SSP target port shall retry connection requests to an SSP initiator port that are
rejected with responses indicating the SSP initiator port may no longer be present before recognizing an I_T nexus loss. table 343 defines
the values of the I_T NEXUS LOSS TIME field. If this mode page is not implemented, the I_T nexus loss time is vendor specific. This value
is enforced by the port layer.
Table 343

I_T NEXUS LOSS TIME values

Code
0000h
0001h to FFFEh
FFFFh
Note.

Description
Vendor-specific amount of time.
Time in milliseconds.
The SSP target port shall never recognize an I_T nexus loss
(i.e., it shall retry the connection requests forever).

If this mode page is implemented, the default value of the I_T NEXUS LOSS TIME field should be non-zero. It is recommended that this value be 2 000 ms.

INITIATOR RESPONSE TIMEOUT field
The INITIATOR RESPONSE TIMEOUT field contains the time in milliseconds that the SSP target port shall wait for the receipt of a frame
(e.g., a write DATA frame) before aborting the command associated with that frame. An INITIATOR RESPONSE TIMEOUT field value of
zero indicates that the SSP target port shall disable the initiator response timeout timer. If this mode page is not implemented, the logical
unit shall not implement an initiator response timeout timer. This value is enforced by the transport layer.

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4.3.18.3.3

Protocol-Specific Port mode page- short format - SAS-3

This clause describes the Protocol-Specific Port mode page implemented by products that are SAS-3 compliant. The Protocol-Specific
Port mode page contains parameters that affect SSP target port operation. If the mode page is implemented by one logical unit in a SCSI
target device, then it shall be implemented by all logical units in the SCSI target device that support the MODE SELECT or MODE SENSE
commands.
The mode page policy (see 4.4.12) for this mode page shall be either shared or per target port. If a SAS target device has multiple SSP
target ports, then the mode page policy should be per target port.
Parameters in this mode page:
a) shall affect all phys in the SSP target port if the mode page policy is per target port; or
b) shall affect all SSP target ports in the SAS target device if the mode page policy is shared.
Table 344 defines the format of the page for SAS SSP.
Table 344

Protocol-Specific Port mode page for SAS SSP- short format - SAS-3

Bit
Byte
0
1

7

6

PS

SPF (0b)

2

Reserved

CONTINUE
AWT

3
4
5
6
7
8
9
10
...
15

5

4

3

2

1

0

PAGE CODE (19h)
PAGE LENGTH (0Eh)
BROADCAST
ASYNCHRONOUS
EVENT

READY LED
MEANING

PROTOCOL IDENTIFIER (6h)

Reserved
(MSB)
(MSB)

I_T NEXUS LOSS TIME
INITIATOR RESPONSE TIMEOUT

(MSB)

REJECT TO OPEN LIMIT

(LSB)
(LSB)
(LSB)

Reserved

The PARAMETERS SAVEABLE (PS) bit is defined in 4.3.5.
The SPF field shall be set to zero for access to the short format mode page.
The PAGE CODE field shall be set to 19h.
The PAGE LENGTH field shall be set to 0Eh.
CONTINUE AWT BIT
0

A CONTINUE AWT bit set to zero specifies that the SAS port shall stop the Arbitration Wait Time timer and set the Arbitration Wait
Time timer to zero when it receives an OPEN_REJECT (RETRY).

1

A CONTINUE AWT bit set to one specifies that the SAS port shall not stop the Arbitration Wait Time timer and shall not set the Arbitration Wait Time timer to zero when the SAS port receives an OPEN_REJECT (RETRY).

BROADCAST ASYNCHRONOUS EVENT bit
0

A BROADCAST ASYNCHRONOUS EVENT bit set to zero specifies that the device server shall disable origination of Broadcast
(Asynchronous Event).

1

A BROADCAST ASYNCHRONOUS EVENT bit set to one specifies that the device server shall enable origination of Broadcast
(Asynchronous Event) (see SAS-3).

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READY LED MEANING bit
The READY LED MEANING bit specifies the READY LED signal behavior (see SAS-3). Regardless of the mode page policy (see 4.4.12)
for this mode page, the shared mode page policy shall be applied to the READY LED MEANING bit.
PROTOCOL IDENTIFIER field
The PROTOCOL IDENTIFIER field is defined in 4.3.17 and shall be set to the value defined in table 325 indicating that this is a SAS SSP
specific mode page.
I_T NEXUS LOSS TIME field
The I_T NEXUS LOSS TIME field is defined in 4.3.18.3.2.I
INITIATOR RESPONSE TIMEOUT field
The INITIATOR RESPONSE TIMEOUT field is defined in 4.3.18.3.2.
REJECT TO OPEN LIMIT field
The REJECT TO OPEN LIMIT field contains the minimum time in 10 μs increments that the target port shall wait to establish a connection
request with an initiator port on an I_T nexus after receiving an OPEN_REJECT (RETRY), OPEN_REJECT (RESERVED CONTINUE 0),
or OPEN_REJECT (RESERVED CONTINUE 1). This value may be rounded as defined in 2.3. A REJECT TO OPEN LIMIT field set to
0000h indicates that the minimum time is vendor specific. This minimum time is enforced by the port layer (see SAS-3).

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4.3.18.3.4

Protocol-Specific Port mode page - Phy Control And Discover subpage (19h)

The Phy Control And Discover subpage contains phy-specific parameters. The mode page policy (see 4.4.12) for this subpage shall be
shared. Parameters in this subpage shall affect only the referenced phy.
Table defines the format of the subpage for SAS SSP.
Table 345

Protocol-Specific Port mode page SAS SSP - Phy Control And Discover subpage

Bit
Byte

7

6

5

0

PS

SPF (1B)

3

2

1

0

PAGE CODE (19h)
SUBPAGE CODE (01h)

1
2

4

(MSB)
PAGE LENGTH (N - 3)
(LSB)

3
Reserved

4
Reserved

5

PROTOCOL IDENTIFIER (6h)

6

GENERATION CODE

7

NUMBER OF PHYS
SAS phy mode descriptor list

8
FIRST SAS PHY MODE DESCRIPTOR (see table 346)
...
...

...

...
LAST SAS PHY MODE DESCRIPTOR (see table 346)
n
The PARAMETERS SAVEABLE (PS) bit is defined in 4.3.5.
The SPF field (see 4.3.5) shall be set to one to access the long format mode pages.
The PAGE CODE field (see 4.3.5) shall be set to 19h.
The SUBPAGE CODE field (see 4.3.5) shall be set to 01h.
The PAGE LENGTH field (see 4.3.5) shall be set to (4 + (the value of the NUMBER OF PHYS field) × (the length in bytes of the SAS phy
mode descriptor)).
PROTOCOL IDENTIFIER field
The PROTOCOL IDENTIFIER field shall be set to 6h indicating this is a SAS SSP specific mode page.
GENERATION CODE field
The GENERATION CODE field is a one-byte counter that shall be incremented by one by the device server every time the values in this
mode page or the Enhanced Phy Control mode page (see 4.3.18.3.6) are changed. A GENERATION CODE field set to 00h indicates the
generation code is unknown. The device server shall wrap this field to 01h as the next increment after reaching its maximum value (i.e.,
FFh). The GENERATION CODE field is also contained in the Enhanced Phy Control mode page (see 4.3.18.3.6) and the Protocol-Specific
Port log page (see SAS-3) and may be used to correlate phy settings across mode page and log page accesses.
Note.

Device servers compliant with previous versions of this standard set the GENERATION CODE field to 00h.

NUMBER OF PHYS field
The NUMBER OF PHYS field contains the number of phys in the SAS target device and indicates the number of SAS phy mode descriptors that follow. This field shall not be changeable with MODE SELECT.
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SAS PHY MODE DESCRIPTOR fields
A SAS phy mode descriptor shall be included for each phy in the SAS target device (not just the SAS target port), starting with the lowest
numbered phy and ending with the highest numbered phy.
Table 346 defines the SAS phy mode descriptor.
Table 346
Bit
Byte

SAS phy mode descriptor
7

6

5

4

3

2

0

Reserved

1

PHY IDENTIFIER

2

1

0

Reserved

3
4

Reserved

ATTACHED DEVICE TYPE

Reserved

5

REASON

NEGOTIATED PHYSICAL LINK RATE

6

Reserved

ATTACHED SSP
INITIATOR PORT

ATTACHED STP
INITIATOR PORT

ATTACHED SMP
INITIATOR PORT

Reserved

7

Reserved

ATTACHED SSP
TARGET PORT

ATTACHED STP
TARGET PORT

ATTACHED SMP
TARGET PORT

Reserved

8
SAS ADDRESS

...
15
16

ATTACHED SAS ADDRESS

...
23

ATTACHED PHY IDENTIFIER

24
25

Reserved

...
31
32

PROGRAMMED MINIMUM PHYSICAL LINK RATE

HARDWARE MINIMUM PHYSICAL LINK RATE

33

PROGRAMMED MAXIMUM PHYSICAL LINK RATE

HARDWARE MAXIMUM PHYSICAL LINK RATE

34
...

Reserved

41
42

Vendor specific

43
44
...

Reserved

47
PHY IDENTIFIER field
The PHY IDENTIFIER field indicates the phy identifier (see SPL-3) of the phy for which information is being returned.

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ATTACHED DEVICE TYPE field
The ATTACHED DEVICE TYPE field indicates the device type attached to this phy and is defined in Table 273.
NEGOTIATED PHYSICAL LINK RATE field
If the NEGOTIATED PHYSICAL LINK RATE field (see table 275) is not set to a physical link rate, then the management device server may
set the ATTACHED DEVICE TYPE field to 000b.
ATTACHED SSP INITIATOR PORT bit
An ATTACHED SSP INITIATOR PORT bit set to:
0

zero indicates that an SSP initiator port is not present in the attached device.

1

one indicates that an SSP initiator port is present in the attached device.

ATTACHED STP INITIATOR PORT bit
An ATTACHED STP INITIATOR PORT bit set to one indicates that an STP initiator port is present in the attached device.
ATTACHED SMP INITIATOR PORT bit
An ATTACHED SMP INITIATOR PORT bit set to one indicates that an SMP initiator port is present in the attached device.
ATTACHED SSP TARGET PORT bit
An ATTACHED SSP TARGET PORT bit set to one indicates that an SSP target port is present in the attached device.
ATTACHED STP TARGET PORT bit
An ATTACHED STP TARGET PORT bit set to one indicates that an STP target port is present in the attached device.
ATTACHED SMP TARGET PORT bit
An ATTACHED SMP TARGET PORT bit set to one indicates that an SMP target port is present in the attached device.
SAS ADDRESS field
The SAS ADDRESS field indicates the port identifier (see SPL-3 r02, Section 4.2.9) of the SAS port transmitting the IDENTIFY address
frame. For expander ports, the SAS ADDRESS field indicates the device name (see SPL-3 r02, Section 4.2.6) of the expander device
transmitting the IDENTIFY address frame.
ATTACHED SAS ADDRESS field
The ATTACHED SAS ADDRESS field contains SAS address of the attached SAS port (see SPL-3 r02, Section 4.2.9).
ATTACHED PHY IDENTIFIER
The ATTACHED PHY IDENTIFIER field contains the phy identifier of the attached SAS phy in the attached SAS device.
HARDWARE MINIMUM PHYSICAL LINK RATE field
The HARDWARE MINIMUM PHYSICAL LINK RATE field indicates the minimum physical link rate supported by the phy. The values are
defined in table 347.

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HARDWARE MAXIMUM PHYSICAL LINK RATE field
The HARDWARE MAXIMUM PHYSICAL LINK RATE field indicates the maximum physical link rate supported by the phy. The values are
defined in table 347. If the phy is a virtual phy, this field should be set to the maximum physical link rate supported by the expander device.
Table 347
Code

The HARDWARE MINIMUM & MAXIMUM PHYSICAL LINK RATE field values
Description

0h to 7h

Reserved

8h

1.5 Gbps

9h

3.0 Gbps

Ah

6.0 Gbps

Bh

12.0 Gbps

Ch to Fh

Reserved for future physical link rates

MAXIMUM PHYSICAL LINK RATE field
MAXIMUM PHYSICAL LINK RATE field are defined in the SMP DISCOVER function (see SAS-3). These fields shall not be changeable
with MODE SELECT.
PROGRAMMED MINIMUM PHYSICAL LINK RATE field and PROGRAMMED MAXIMUM PHYSICAL LINK RATE field
The PROGRAMMED MINIMUM PHYSICAL LINK RATE field and PROGRAMMED MAXIMUM PHYSICAL LINK RATE field are defined in
the SMP PHY CONTROL function (see SPL-3 Section 9.4.3.28) for accesses with MODE SELECT commands and in the SMP DISCOVER function (see SPL-3 Section 9.4.3.10) for accesses with MODE SENSE commands.
Table 348 lists the PROGRAMMED MINIMUM and MAXIMUM PHYSICAL LINK RATE field values..
Table 348
Code
0h

The PROGRAMMED MINIMUM and MAXIMUM PHYSICAL LINK RATE field values
Description
Do not change current value

1h to 7h

Reserved

8h

1.5 Gbps

9h

3.0 Gbps

Ah

6.0 Gbps

Bh
Ch to Fh

12.0 Gbps
Reserved for future physical link rates

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4.3.18.3.5

Port Control mode page

The Port Control Mode Page contains parameters that affect SSP target port operation. If the mode page is implemented by one logical
unit in a SCSI target device, then it shall be implemented by all logical units in the SCSI target device that support the MODE SELECT or
MODE SENSE commands.
The mode page policy (see 4.4.12) for this mode page shall be shared.
Table 349 defines the format of this mode page.
Table 349

Port Control Mode Page

Bit
Byte

7

6

5

0

PS

SPF (1b)

(MSB)

2

1

0

PAGE CODE (19h)

PAGE LENGTH (000Ch)

3

(LSB)

Reserved

4
Reserved

5
6

3

SUBPAGE CODE (02h)

1
2

4

(MSB)

7

PROTOCOL IDENTIFIER (6h)
POWER LOSS TIMEOUT

(LSB)

8
...

Reserved

15
The Parameters Saveable (PS) bit is defined in 4.3.5.
The SubPage Format (SPF) bit is defined in 4.3.5 and shall be set to the value defined in table 349.
The PAGE CODE field is defined in 4.3.5 and shall be set to the value defined in table 349.
The SUBPAGE CODE field is defined in 4.3.5 and shall be set to the value defined in table 349.
The PAGE LENGTH field is defined in 4.3.5 and shall be set to the value defined in table 349.
PROTOCOL IDENTIFIER field
The PROTOCOL IDENTIFIER field is defined in 4.3.5 and shall be set to the value defined in table 349 indicating that this is a SAS SSP
specific mode page.
POWER LOSS TIMEOUT field
The POWER LOSS TIMEOUT field contains the maximum time, in one millisecond increments, that a target port shall respond to connection requests with OPEN_REJECT (RETRY) after receiving NOTIFY (POWER LOSS EXPECTED) (see SAS-3). A POWER LOSS TIMEOUT field set to 0000h specifies that the maximum time is vendor-specific. The power loss timeout shall be restarted on each NOTIFY
(POWER LOSS EXPECTED) that is received.

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4.3.18.3.6

Enhanced Phy Control mode page

The Enhanced Phy Control mode page contains parameters that affect SSP target phy operation. If the mode page is implemented by one
logical unit in a SCSI target device, then it shall be implemented by all logical units in the SCSI target device that support the MODE
SELECT or MODE SENSE commands.
The mode page policy (see 4.4.12) for this mode page shall be shared.
Table 350 defines the format of this mode page.
Table 350
Bit
Byte
0
1
2
3
4
5
6
7

Enhanced Phy Control mode page
7

6

5

PS

SPF(1b)

3

2

1

0

PAGE CODE (19h)
SUBPAGE CODE (03h)

(MSB)

8
...
27
...
n - 19
...
n

4

PAGE LENGTH (n - 3)

(LSB)

Reserved
Reserved

PROTOCOL IDENTIFIER (6h)
GENERATION CODE
NUMBER OF PHYS
Enhanced phy control mode descriptor list

Enhanced phy control mode descriptor (first) (see table 351)
...
Enhanced phy control mode descriptor (last) (see table 351)

The Parameters Saveable (PS) bit is defined in 4.3.5.
The SubPage Format (SPF) bit is defined in 4.3.5 and shall be set to the value defined in table 350.
The PAGE CODE field is defined in 4.3.5 and shall be set to the value defined in table 350.
The SUBPAGE CODE field is defined in 4.3.5 and shall be set to the value defined in table 350.
The PAGE LENGTH field is defined in 4.3.5 and shall be set to the value defined in table 350 (i.e., 4 + (the value of the NUMBER OF PHYS
field) ´ (the length in bytes of the SAS phy mode descriptor)).
PROTOCOL IDENTIFIER field
The PROTOCOL IDENTIFIER field is defined in table 325 and shall be set to the value defined in table 350 indicating that this is a SAS
SSP specific mode page.

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GENERATION CODE field
The GENERATION CODE field is defined in the Phy Control and Discover mode page (see 4.3.18.3.4).
NUMBER OF PHYS field
The NUMBER OF PHYS field contains the number of phys in the SAS target device and indicates the number of enhanced phy control
mode descriptors in the enhanced phy control mode descriptor list. This field shall not be changeable with the MODE SELECT command.
ENHANCED PHY CONTROL MODE DESCRIPTOR
The enhanced phy control mode descriptor list contains an enhanced phy control mode descriptor for each phy in the SAS target device,
not just the SAS target port, starting with the lowest numbered phy and ending with the highest numbered phy.
Table 351 defines the enhanced phy control mode descriptor.
Table 351
Bit
Byte
0
1
2
3
4
...
7
8
...
11
12
...
15
16
17

Enhanced phy control mode descriptor
7

6

5

4

3

2

1

0

Reserved
PHY IDENTIFIER
(MSB)

18

DESCRIPTOR LENGTH (0010h)

(LSB)

PROGRAMMED PHY CAPABILITIES

CURRENT PHY CAPABILITIES

ATTACHED PHY CAPABILITIES

Reserved
Reserved

19

NEGOTIATED
SSC
Reserved

NEGOTIATED PHYSICAL LINK RATE
HARDWARE
MUXING
SUPPORTED

PHY IDENTIFIER field
The PHY IDENTIFIER field indicates the phy identifier (see SPL-3) of the phy for which information is being returned.
DESCRIPTOR LENGTH field
The DESCRIPTOR LENGTH field contains the length in bytes that follow in the descriptor and shall be set to the value defined in table
351.
The fields in the enhanced phy control mode descriptor not defined in this subclause are defined in the SMP DISCOVER response (see
SPL-3 Section 9.4.3.10). These fields shall not be changeable with the MODE SELECT command.

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PROGRAMMED PHY CAPABILITIES field
The PROGRAMMED PHY CAPABILITIES field indicates the SNW-3 phy capabilities bits that are going to be transmitted in the next link
reset sequence containing SNW-3 as defined in SPL-3 Section 5.7.
CURRENT PHY CAPABILITIES field
The CURRENT PHY CAPABILITIES field indicates the outgoing SNW-3 phy capabilities bits transmitted in the last link reset sequence as
defined in SPL-3 Section 5.7. If the last link reset sequence did not include SNW-3 or was a SATA link reset sequence, then the CURRENT
PHY CAPABILITIES field shall be set to 00000000h.
ATTACHED PHY CAPABILITIES field
The ATTACHED PHY CAPABILITIES field indicates the incoming SNW-3 phy capabilities bits received in the last SNW-3 as defined in
SPL-3 Section 5.7. If the last link reset sequence did not include SNW-3 or was a SATA link reset sequence, then the ATTACHED PHY
CAPABILITIES field shall be set to 00000000h.
NEGOTIATED SSC bit
A NEGOTIATED SSC bit set to:
0

indicates that SSC is disabled

1

indicates that SSC is enabled (see SAS-3)

The NEGOTIATED SSC bit is only valid if the NEGOTIATED PHYSICAL LINK RATE field is greater than or equal to 8h.
NEGOTIATED PHYSICAL LINK RATE field
The NEGOTIATED PHYSICAL LINK RATE field is defined in table 275. If the phy is a physical phy, this field indicates the physical link rate
negotiated during the link reset sequence. If the phy is a virtual phy, this field should be set to the maximum physical link rate supported by
the expander device. The negotiated physical link rate may be less than the programmed minimum physical link rate or greater than the
programmed maximum physical link rate if the programmed physical link rates have been changed since the last link reset sequence.
HARDWARE MUXING SUPPORTED bit
A HARDWARE MUXING SUPPORTED bit set to:
0

indicates that the phy does not support multiplexing

1

indicates that the phy supports multiplexing (see SPL-3 Section 5.15)

This value is not adjusted based on the negotiated physical link rate.

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4.3.18.3.7

Protocol-Specific Port – Transceiver Control (Out) subpage (19h/E5h)

The Transceiver Control (Out) subpage (see table 352) of the Protocol-Specific Port mode page is used to adjust the transceiver parameter
values of a phy. This subpage, when implemented, must comply with the following additional itemized requirements:
1) The transceiver parameter settings may only be adjusted temporarily using the contents of this mode page, and cannot be saved.
2) New phy settings are not to take effect until after status is returned for the MODE SELECT command that is issued to adjust the
phy settings.
3) The Transceiver Control subpage shall not be returned for a MODE SENSE command to return all pages. It shall only be returned
to a MODE SENSE command, specifically, for the Transceiver Control subpage (19h/E5h).
4) Transceiver Control Subpage E5h must include all mode descriptor for each link rate of each phy. For non-supported link rate, fill
the mode desciptor bytes with 00.
Table 352
Bit
Byte
0
1
2
3
4
5
6
7
8
...
14
15
16
...
32
...
48
...
64
...
80
...
96
...
112
...
128
...
144

Transceiver Control (Out) subpage
7

6

5

PS

SPF(1b)

4

3

2

1

0

PAGE CODE (19h)
SUBPAGE CODE (E5h)

(MSB)

PAGE LENGTH (n - 3)

(LSB)

Reserved
Reserved

PROTOCOL IDENTIFIER (6h)

Reserved
NUMBER OF PHYS (02h for a dual ported disk drive)
Reserved
TRANSCEIVER CONTROLS MODE DESCRIPTORS LENGTH
Phy Transceiver Controls mode descriptor (first) PHY IDENTIFIER = 0
CONTROLLABLE LINK RATE = 08h
...
Phy Transceiver Controls mode descriptor (first) PHY IDENTIFIER = 0
CONTROLLABLE LINK RATE = 09h
...
Phy Transceiver Controls mode descriptor (first) PHY IDENTIFIER = 0
CONTROLLABLE LINK RATE = 0Ah
...
Phy Transceiver Controls mode descriptor (first) PHY IDENTIFIER = 0
CONTROLLABLE LINK RATE = 0Bh
...
Phy Transceiver Controls mode descriptor (second) PHY IDENTIFIER = 1
CONTROLLABLE LINK RATE = 08h
...
Phy Transceiver Controls mode descriptor (second) PHY IDENTIFIER = 1
CONTROLLABLE LINK RATE = 09h
...
Phy Transceiver Controls mode descriptor (second) PHY IDENTIFIER = 1
CONTROLLABLE LINK RATE = 0Ah
...
Phy Transceiver Controls mode descriptor (second) PHY IDENTIFIER = 1
CONTROLLABLE LINK RATE = 0Bh
...
00

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The PARAMETERS SAVEABLE (PS) bit is defined in SPC-4.
The SUBPAGE FORMAT (SPF) bit is defined in SPC-4 and shall be set to the value defined in table 352.
The PAGE CODE field is defined in SPC-4 and shall be set to the value defined in table 352.
The SUBPAGE CODE field is defined in SPC-4 and shall be set to the value defined in table 352.
PAGE LENGTH field
The PAGE LENGTH field is defined in SPC-4 and shall be set to the value defined in table 352 (i.e., 4 + ((the value of the NUMBER OF
PHYS field) × (the length in bytes of the SAS phy mode descriptor))).
PROTOCOL IDENTIFIER field
The PROTOCOL IDENTIFIER field is defined in SPC-4 and shall be set to the value defined in table 352 indicating that this is a SAS SSP
specific mode page.
NUMBER OF PHYS field
The NUMBER OF PHYS field contains the number of phys in the SAS target device and indicates the number of enhanced phy control
mode descriptors in the enhanced phy control mode descriptor list. If a target device has 2 operational target ports (2 phys), then this field
shall be set to 2h. Target devices with only one port shall set this field to 1h. This field shall not be changeable with the MODE SELECT
command.
TRANSCEIVER CONTROLS MODE DESCRIPTORS LENGTH fields
This Transceiver Controls Mode Descriptors Length fields shall contain the total length in bytes of each phy's transceiver controls mode
descriptor. Since the descriptors are the same length, this value is not provided in each descriptor, but rather, once in this subpage prior to
the descriptor(s). The field is unchangeable.
4.3.18.3.7.1

Transceiver Controls Mode descriptors

Detail for the mode descriptor(s) for transceiver controls can be found in Table 353 and Table 354. Each field is defined below the table. All
supported link rates and controls shall be listed in page E5h.
Table 353
Bit
Byte

Transceiver Controls Mode descriptor (1.5Gb - 6Gb Link Rate)
7

6

5

4

3

2

0

PHY IDENTIFIER

1

CONTROLLABLE LINK RATE

2

DRIVER STRENGTH CONTROL

3

DRIVER EMPHASIS CONTROL

4

DRIVER SLEW RATE CONTROL

1

0

5
...

MANUFACTURER DEFINE BYTES FOR TRANSMITTER CONTROL

8
9

RECEIVER THRESHOLD CONTROL

10

RECEIVER EQUALIZATION GAIN CONTROL

11

MANUFACTURER DEFINE BYTES FOR RECEIVER CONTROL

12
13

INTERNAL RX EYE MARGIN

RESET

14

INTERNAL RX EYE HEIGHT

15

INTERNAL RX EYE WIDTH

SCSI Commands Reference Manual, Rev. H

Reserved

Reserved

IREC

319

Table 354

Transceiver Controls descriptor (12Gb Link Rate)

Bit
Byte

7

6

5

4

3

2

1

0

Reserved

IREC
COMPLETED

IREC

0

PHY IDENTIFIER

1

CONTROLLABLE LINK RATE

2

C1 VALUE OF TX

3

C2 VALUE OF TX

4

C3 VALUE OF TX
Reserved

5

RESET

6

FFE COEFFICIENT 0 / INTERNAL RX EYE HEIGHT MARGIN

7

FFE COEFFICIENT 1 / INTERNAL RX EYE HEIGHT MARGIN

8

DFE COEFFICIENT 0

9

DFE COEFFICIENT 1

10

DFE COEFFICIENT 2

11

DFE COEFFICIENT 3

12

DFE COEFFICIENT 4

13

HOST C1 RELATIVE VALUE

14

HOST C2 RELATIVE VALUE

15

HOST C3 RELATIVE VALUE

PHY IDENTIFIER field
SAS devices may have more than one target port. If a target device has 2 operational target ports (2 phys - primary and secondary port),
then this field shall be set to either 0h for the primary port or 1h for the secondary port. This field is unchangeable.
CONTROLLABLE LINK RATE field
The Controllable Link Rate field shall contain the controllable link rate for the phy. Table 355 lists the supported values Controllable Link
Rates. This field is not changeable.
Table 355

Controllable Link Rates

Value

Definition

0x00

Phy exists, but does not support “Transceiver Control” controls

0x01 – 0x07

Reserved

0x08

Phy supports Transceiver Control controls for 1.5 Gbps

0x09

Phy supports Transceiver Control controls for 3.0 Gbps

0x0A

Phy supports Transceiver Control controls for 6.0 Gbps

0x0B

Phy supports Transceiver Control controls for 12.0 Gbps

0x0C – 0xFF

Reserved

DRIVER STRENGTH CONTROL or C1 PRE-CURSOR CONTROL (12Gb only) field
This field shall contain either the user input (MODE SELECT) or current (MODE SENSE) driver strength output or the 12G mode pre-cursor C1 setting of the SAS transmitter. If the user input setting is out of range of the transceiver capability, the target device shall return a
CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN
PARAMETER LIST for the MODE SELECT command. This field shall be supported as described in Table 356. The field is changeable but
not savable.

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Table 356

DRIVER STRENGTH CONTROL or C1 PRE-CURSOR CONTROL (12G Mode Only) values
Value

0x66 (write only)
(1.5G - 6G)
0x00 – Range Limit
(write only)
Read Only

Definition
Write 66h shall reset the driver strength setting back to factory default value.
User input for driver strength control setting or C1 pre-cursor setting.
If the new user input is out of range specified in subpage 19h/E5h,
the target device shall maintain the current setting.
The current setting value shall be displayed.

DRIVER EMPHASIS CONTROL or C2 AMPLITUDE CONTROL (12G Mode Only) field
This field shall contain either the user input (MODE SELECT) or current (MODE SENSE) driver emphasis setting the 12G mode amplitude
C2 setting of the SAS transmitter. If the user input setting is out of range of the transceiver capability, the target device shall return a
CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN
PARAMETER LIST for the MODE SELECT command. This field shall be supported as described in Table 357. This field is changeable but
not savable.
Table 357

DRIVER EMPHASIS CONTROL or C2 AMPLITUDE CONTROL (12G Mode Only)
Value

0x66 (write only)
(1.5G - 6G)
0x00 – Range Limit
(write only)
Read Only

Definition
Write 66h shall reset the driver pre-emphasis setting back to factory default value.
User input for driver pre-emphasis control setting or C2 amplitude setting.
If the new user input is out of range specified in subpage 19h/E5h,
the target device shall maintain the current setting.
The current setting value shall be displayed.

DRIVER SLEW RATE CONTROL or C3 CONTROL (12G Mode Only) field
This field shall contain either the user input (MODE SELECT) or current (MODE SENSE) driver slew rate setting of the target device SAS
phy. If the user input setting is out of range of the transceiver capability, the target device shall return a CHECK CONDITION status with
the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN PARAMETER LIST for the MODE
SELECT command. This field shall be supported as described in Table 358. This field is changeable but not savable.
Table 358

DRIVER SLEW RATE CONTROL or C3 POST CURSOR CONTROL (12G mode only)
Value

0x66 (write only)
(1.5G - 6G)
0x00 – Range Limit
(write only)
Read Only

Definition
Write 66h shall reset the driver slew rate setting back to factory default value.
User input for driver slew rate control setting or C3 post cursor setting.
If the new user input is out of range specified in subpage 19h/E5h,
the target device shall maintain the current setting
The current setting value shall be displayed.

MANUFACTURER DEFINED BYTES FOR TRANSMITTER CONTROL field
The manufacturer Defined Bytes For Transmitter Control field may be used by the manufacturer who needs additional control bytes for the
transmitter. All control bytes shall accept 66h as reset code which change the control byte back to factory default setting. If the user input
setting is out of range of the transceiver capability, the target device shall return a CHECK CONDITION status with the sense key set to
ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN PARAMETER LIST for the MODE SELECT command.

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RECEIVER THRESHOLD CONTROL field
The Receiver Threshold Control field contains either the user input (MODE SELECT) or current (MODE SENSE) receiver threshold setting
of the target device SAS phy. If the user input setting is out of range of the transceiver capability, the target device shall return a CHECK
CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN PARAMETER
LIST for the MODE SELECT command. The Receiver Threshold Control field shall be supported as described in table 359. This field is
changeable but not savable.
Table 359

Receiver Threshold Control
Value

0x66 (write only)
0x00 – Range Limit
(write only)
Read Only

Definition
Write 66h shall reset the receiver threshold setting back to factory default value.
User input for receiver threshold control setting. If the new user input is out of range specified
in subpage 19h/E5h, the target device shall maintain the current setting.
The current setting value shall be displayed.

RECEIVER EQUALIZATION GAIN CONTROL field
The Receiver Equalization Gain Control field contains either the user input (MODE SELECT) or current (MODE SENSE) receiver equalization gain setting of the target device SAS phy. If the user input setting is out of range of the transceiver capability, the target device shall
return a CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD
IN PARAMETER LIST for the MODE SELECT command. This field shall be supported as described in table 360. This field is changeable
but not savable.
Table 360

Receiver Equalization Gain Control field
Value

Definition

0x66 (write only)

Write 66h shall reset the receiver equalization gain setting back to factory default value for
the driver voltage.

0x00 – Range Limit
(write only)

User input for receiver equalization gain control setting. If the new user input is out of range
specified in subpage 19h/E5h, the target device shall maintain the current setting

Read Only

The current setting value shall be displayed.

MANUFACTURER DEFINED BYTES FOR RECEIVER CONTROL field
The Manufacturer Defined Bytes For Receiver Control field may be used by manufacturer who needs additional control bytes for the
receiver. All control bytes shall accept 66h as reset code which change the control byte back to factory default setting. If the user input setting is out of range of the transceiver capability, the target device shall return a CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN PARAMETER LIST for the MODE SELECT command.
EYE WIDTH MARGIN and EYE HEIGHT MARGIN field - Read Only
These fields shall contain IRE margin after IREC (Internal RX Eye Capture) is performed. The margin calculation are based on the following formula:
Eye Width Margin = (Captured Eye Width - Spec Min Eye Width) / Spec Min Eye Width x 100%
Eye Height Margin = (Captured Eye Height - Spec Min Height Width) / Spec Min Eye Height x 100%
In case the Captured Eye is less than Spec Min. Eye, then FFh should be used.
IREC (INTERNAL RX EYE CAPTURE) bit
This bit controls the Internal RX Eye Capture process (see table 360), and provides the internal eye height, eye width and eye margin.
IREC COMPLETED bit - Read Only
This bit indicates the Internal RX Eye Capture process (see table 360) is completed and provides the internal eye height, eye width and
eye margin.

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322

RESET bit
This bit controls the TX to C1, C2 and C3, and controls the reset function of IREC bits (see table 360).
Table 361

RESET and IREC bit function

RESET
(Mode
Select)

IREC
(Mode
Select)

IREC
Completed

0

0

0

• No change on current C1, C2, C3
• All FFE and DFE coeffiecients shall be updated

1

•
•
•
•

0

1

1

0

0

1

Mode Sense data after Mode Select was executed
with different RESET bit and IREC bit settings.

Set IREC Completed bit to 1 when RX eye capture is completed
IRC Margin shall be displayed
RX eye height and eye width shall be displayed instead of RX FFE coefficients.
All DFE coeffiecients shall be updated

Don’t
Care

• Set TX to C1, C2, C3 (no retrain)
• All FFE and DFE coeffiecients shall be updated
• After reset operation completed, Reset bit shall be set to 0,
IREC Completed bit shall be set to 0.
• All FFE and DFE coeffiecients shall be updated.

Don’t
Care

• No change on current C1, C2, C3
• Perform internal RX eye capture
• After RX eye capture completed,
Reset bit shall be set to 0 and IREC Completed bit shall be set to 1.
• IRC Margin shall be displayed
• RX eye height and eye width shall be displayed instead of RX FFE coefficients.
• All DFE coeffiecients shall be updated

FFE TAP 0, 1 / RX EYE HEIGHT AND RX EYE WIDTH (Read only)
The FFE Tap 0, 1 field shall contain the current (MODE SENSE) FFE Tap 0 and Tap 1 coefficient with the RESET bit is set to 0 and IREC
Completed bit set to 0. The RX Eye Height And RX Eye Width fields shall contain the current (MODE SENSE) RX eye height and RX eye
width with IREC completed bit set to 1.
DFE COEFFICIENT 0 - 4 (Read only)
This field shall contain the current (MODE SENSE) DFE coefficient of the receiver. If the number of DFE coefficients is more than 5, then
only the first 5 coefficients shall be displayed.
HOST TRANSMITTER C1, C2 AND C3 RELATIVE SETTING (Read Only)
This field shall contain the user input (MODE SELECT) of the C1, C2 and C3 relative setting of host transmitter.
During the speed negotiation, the C1, C2 and C3 of the Host transmiiter will be adjusted by Up or Hold or Down.
Keep track of the adjustment by each Up = +1, each Hold = 0 and each Down = -1, i.e. C1 is adjusted by 3 Up tics and 1 Down,
the relative Host C1 is 1+1+1-1 = 2.

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4.3.18.3.8

Protocol-Specific Port – Transceiver Control (In) subpage (19h/E6h)

The Transceiver Control (In) subpage of the Protocol-Specific Port mode page (see table 362) is used to return the transceiver parameter
values of a phy. The Transceiver Control subpage shall not be returned for a MODE SENSE command to return all pages. It shall only be
returned to a MODE SENSE command, specifically, for the Transceiver Control subpage (19h/E6h). The target device shall return a
CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD IN
PARAMETER LIST for a MODE SELECT command issued for this subpage.
Table 362

Protocol-Specific Port - Transceiver Control (In) subpage

Bit
Byte

7

6

5

0

PS

SPF (1b)

2

1

0

SUBPAGE CODE (E6h)
(MSB)

PAGE LENGTH (n-3)

3

(LSB)

Reserved

4
5

3

Page Code (19h)

1
2

4

Reserved

PROTOCOL IDENTIFIER (6h)

6

Reserved

7

NUMBER OF PHYS (02h for a dual ported disk drive)

8
Reserved

...
14
15

TRANSCEIVER CONTROLS MODE DESCRIPTOR LENGTH = 16

16

Phy Transceiver Controls mode descriptor (first) PHY IDENTIFIER = 0
CONTROLLABLE LINK RATE = 08h

...

...

32

Phy Transceiver Controls mode descriptor (first) PHY IDENTIFIER = 0
CONTROLLABLE LINK RATE = 09h

...

...

48

Phy Transceiver Controls mode descriptor (first) PHY IDENTIFIER = 0
CONTROLLABLE LINK RATE = 0Ah

...

...

64

Phy Transceiver Controls mode descriptor (first) PHY IDENTIFIER = 0
CONTROLLABLE LINK RATE = 0Bh

...

...

80

Phy Transceiver Controls mode descriptor (second) PHY IDENTIFIER = 1
CONTROLLABLE LINK RATE = 08h

...

...

96

Phy Transceiver Controls mode descriptor (second) PHY IDENTIFIER = 1
CONTROLLABLE LINK RATE = 09h

...

...

112

Phy Transceiver Controls mode descriptor (second) PHY IDENTIFIER = 1
CONTROLLABLE LINK RATE = 0Ah

...

...

128

Phy Transceiver Controls mode descriptor (second) PHY IDENTIFIER = 1
CONTROLLABLE LINK RATE = 0Bh

...

...

144

00

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324

The PARAMETERS SAVEABLE (PS) bit is defined in SPC-4.
The SUBPAGE FORMAT (SPF) bit is defined in SPC-4 and shall be set to the value defined in table 362.
The PAGE CODE field is defined in SPC-4 and shall be set to the value defined in table 362.
The SUBPAGE CODE field is defined in SPC-4 and shall be set to the value defined in table 362.
PAGE LENGTH field
The PAGE LENGTH field is defined in SPC-4 and shall be set to the value defined in table 362 (i.e., 4 + ((the value of the NUMBER OF
PHYS field) × (the length in bytes of the SAS phy mode descriptor))).
PROTOCOL IDENTIFIER field
The PROTOCOL IDENTIFIER field is defined in SPC-4 and shall be set to the value defined in table 362 indicating that this is a SAS SSP
specific mode page.
NUMBER OF PHYS field
SAS devices may have more than one target port. If a target device has 2 operational target ports (2 phys), then this field shall be set to 2h.
Target devices with only one port shall set this field to 1h. The field is unchangeable.
TRANSCEIVER CONTROLS MODE DESCRIPTOR LENGTH field
The Transceiver Controls Mode Descriptor Length field shall contain the total length in bytes of each phy’s transceiver controls mode
descriptor. Since the descriptors are the same length, this value is not provided in each descriptor, but rather, once in this subpage prior to
the descriptor(s). The field is unchangeable.
4.3.18.3.8.1

Transceiver Controls Mode descriptors

Detail for the mode descriptor(s) for transceiver controls can be found in Table 363 and Table 364. Each field is defined below the table. All
supported link rates and controls shall be listed in page E5h.
Table 363
Bit
Byte

Transceiver Controls descriptor (1.5Gb - 6Gb Link Rate)
7

6

5

4

3

2

0

PHY IDENTIFIER

1

CONTROLLABLE LINK RATE

2

DRIVER STRENGTH CONTROL

3

DRIVER EMPHASIS CONTROL

4

DRIVER SLEW RATE CONTROL

1

0

5
...

MANUFACTURER DEFINE BYTES FOR TRANSMITTER CONTROL

8
9

RECEIVER THRESHOLD CONTROL

10

RECEIVER EQUALIZATION GAIN CONTROL

11

MANUFACTURER DEFINE BYTES FOR RECEIVER CONTROL

12
13

INTERNAL RX EYE MARGIN

RESET

14

INTERNAL RX EYE HEIGHT

15

INTERNAL RX EYE WIDTH

SCSI Commands Reference Manual, Rev. H

Reserved

Reserved

IREC

325

Table 364

Transceiver Controls descriptor (1.5G, 3G, 6G and 12G)

Bit
Byte

7

6

5

4

3

2

1

0

PHY IDENTIFIER

1

CONTROLLABLE LINK RATE

2

MAX DRIVER STRENGTH CONTROL
[12G: MAX C1 WHEN C2 AND C3 ARE SET TO MIN]

3

MAX DRIVER EMPHASIS CONTROL
[12G: MAX C1 WHEN C1 AND C3 ARE SET TO 0]

4

MAX DRIVER SLEW RATE CONTROL
[12G: MAX C1 WHEN C1 AND C2 ARE SET TO MIN]

5

DRIVER STRENGTH CONTROL CHANGE PER STEP
[12G: C1 CHANGE PER STEP]

6

DRIVER EMPHASIS CONTROL CHANGE PER STEP
[12G: C2 CHANGE PER STEP]

7

DRIVER SLEW RATE CONTROL CHANGE PER STEP
[12G: C2 CHANGE PER STEP]

8

Reserved (00h)

9

MAX RECEIVER THRESHOLD CONTROL

10

MAX RECEIVER EQUALIZATION GAIN CONTROL

11

RECEIVER THRESHOLD CONTROL CHANGE PER STEP

12

RECEIVER EQUALIZATION GAIN CONTROL CHANGE PER STEP

13-15

Reserved

0

PHY IDENTIFIER field
SAS devices may have more than one target port. If a target device has 2 operational target ports (2 phys - primary and secondary port),
then this field shall be set to either 0h for the primary port or 1h for the secondary port. The field is unchangeable.
CONTROLLABLE LINK RATE field
This field shall contain the controllable link rate for the phy. Table 365 lists the supported values for the field. This field is not changeable.
Table 365

Controllable Link Rates field

Value

Definition

0x00

Phy exists, but does not support Transceiver Control controls

0x01 – 0x07

Reserved

0x08

Phy supports Transceiver Control controls for 1.5 Gbps

0x09

Phy supports Transceiver Control controls for 3.0 Gpbs

0x0A

Phy supports Transceiver Control controls for 6.0 Gbps

0x0B

Phy supports Transceiver Control controls for 12.0 Gbps

0x0C – 0xFF

Reserved

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326

MAX DRIVER STRENGTH CONTROL or C1 MAX SETTING when C2 and C3 set to MIN (12G Mode Only) field
This field shall contain the max allowable driver strength output setting of the target device SAS phy. The field is changeable but not
savable.
MAX DRIVER EMPHASIS CONTROL or C2 MAX SETTING when C1 and C3 set to 0 (12G Mode Only) field
This field shall contain the max allowable driver emphasis setting of the target device SAS phy. This field is changeable but not savable.
MAX DRIVER SLEW RATE CONTROL or C3 CONTROL (12G Mode Only) field
This field shall contain the max allowable driver slew rate setting of the target device SAS phy. This field is changeable but not savable.
DRIVER STRENGTH CONTROL CHANGE PER STEP or C1 CONTROL (12G Mode Only) field
This field shall contain the approximate voltage change (in mV unit) for each increment or decrement of driver strength control setting. The
field is unchangeable.
DRIVER EMPHASIS CONTROL CHANGE PER STEP or C2 CONTROL (12G Mode Only) field
This field shall contain the approximate percentage of amplitude change (in % unit) for each increment or decrement of driver emphasis
control setting. This field shall be used to establish the transceiver driver pre-emphasis or de-emphasis. The field value should be treated
as a 2's-complement signed value that can range from 1 to +100 for pre-emphasis, or -1 to -100 for de-emphasis. The field is unchangeable.
DRIVER SLEW RATE CONTROL CHANGE PER STEP or C3 CONTROL (12G Mode Only) field
This field shall contain the approximate slew rate change (in mV/nsec unit) for each increment or decrement of driver slew rate control setting. The field is unchangeable.
MAX RECEIVER THRESHOLD CONTROL field
This field contains max allowable threshold setting of the target device SAS phy. The field is unchangeable.
MANUFACTURER DEFINED BYTES INFO FOR TRANSMITTER CONTROL field
This field can be used by manufacturer who needs additional control bytes for the transmitter.
MAX RECEIVER EQUALIZATION GAIN CONTROL field
This field contains the max allowable receiver equalization gain setting of the target device SAS phy. The field is unchangeable.
RECEIVER THRESHOLD CONTROL CHANGE PER STEP field
This field shall contain the approximate voltage change (in mV unit) for each increment or decrement of receiver threshold control setting.
The field is unchangeable.
RECEIVER EQUALIZATION GAIN CONTROL CHANGE PER STEP field
This field shall contain the approximate gain change for each increment or decrement of receiver equalization gain control setting. The field
is unchangeable.
MANUFACTURER DEFINED BYTES INFO FOR RECEIVER CONTROL field
This field can be used by manufacturer who needs additional control bytes for the receiver.

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4.3.19

Rigid Drive Geometry Parameters page (04h)

This mode page has been declared obsolete by the T10 committee. However, it is included because it may be implemented on some
products.
The Rigid Drive Geometry Parameters page implementation is defined in Table 366 . This table summarizes the function and defines the
default value.
Table 366

Rigid Drive Geometry Parameters page (04h)

Bit
Byte

7

6

0

PS

Reserved

5

4

3

2

PAGE LENGTH (16h)

2

NUMBER OF CYLINDERS (MSB)

3

NUMBER OF CYLINDERS

4

NUMBER OF CYLINDERS (LSB)

5

NUMBER OF HEADS

6,7,8

STARTING CYLINDER—WRITE PRECOMP

9,10,11

STARTING CYLINDER—REDUCED WRITE CURRENT

12,13

DRIVE STEP RATE

14,15,16

LANDING ZONE CYLINDER
0

0

0

0

0

18

ROTATIONAL OFFSET XXh

19

Reserved

20

0

PAGE CODE (04h)

1

17

1

(MSB)

0

MEDIUM ROTATION RATE

21
22

Reserved

23

Reserved

RPL

(LSB)

PS (Parameter Savable) bit
The Parameter Savable (PS) bit of 1 indicates that page 04 parameter data is savable and is saved when a Format Function is performed.
In some drives an exception exists that applies to bytes 17 and 18. In the exception drives, bytes 17 and 18 are only saved if the SMP bit
in the MODE SELECT command (Table 63) is 1. See individual drive’s Product Manual, Volume 1, SCSI bus conditions and miscellaneous
features supported.” This PS bit is not applicable to the MODE SELECT command.
PAGE CODE field
The PAGE CODE field is defined in SPC-4 and shall be set to the value defined in table 366.
PAGE LENGTH field
The PAGE LENGTH field is defined in SPC-4 and shall be set to the value defined in table 366.

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NUMBER OF CYLINDERS field
The NUMBER OF CYLINDERS field defines the number of physical cylinders used for data storage. This may or may not include spare
cylinders set aside for flaw reallocation. See individual drive’s Product Manual, Volume 1, which specifies what the drive reports.
The drive uses some additional cylinders for storing drive parameters, defect lists, or for diagnostic purposes. These are not accessible by
the user.
NUMBER OF HEADS field
The NUMBER OF HEADS field indicates the maximum number of data (read/write) heads on the drive.
STARTING CYLINDER—WRITE PRECOMP, STARTING CYLINDER—REDUCED WRITE CURRENT, DRIVE STEP RATE, and LANDING ZONE CYLINDER fields
Not applicable.
RPL (rotational position locking) field
Used for Spindle Synchronization (rotational position locking) (see table 367).
Table 367

Rotational Position Locking

RPL

Description

00b

Indicates that spindle synchronization is automatic. (Automatic master arbitration is used to determine
which device in the chain is to be master.)

01b

The target operates as a synchronized-spindle slave.

10b

The target operates as a synchronized-spindle master.

11b

The target operates as a synchronized-spindle master control (not supported by drive).

ROTATIONAL OFFSET field
Rotational skew in the lagging direction used for spindle synchronization. The value XXh given represents a XXh/FFh fractional part of a
revolution lagging offset. One revolution lag is maximum. See clause on Synchronous Spindle Operation in individual drive’s Product Manual, Volume 1.
MEDIUM ROTETION RATE field
On MODE SENSE command, these bytes return drive nominal rotation rate in revolutions per minute for synchronous spindle operation.
The bytes have no meaning for MODE SELECT.
See individual drive’s Product Manual, MODE SENSE Data clause, for changeable values.

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4.3.20

Seagate Specific Unit Attention parameters page (00h)

The Seagate SpecificUnit Attention parameters page is the last page to be reported by the drive.
Table 368

Seagate SpecificUnit Attention parameters page (00h)

Bit
Byte

7

0

PS

6

5

4

3

2

1

0

ROUND

STRICT

SCSI-2

JIT2

JIT1

JIT0

PAGE CODE (00h)
PAGE LENGTH (in bytes)

1
2

PM

SSM

3

DAR

SELF
SEEK

4

VJIT
Disabled

INQUIRY
LENGTH

UNIT
ATTENTION

DFUA
Reserved

Reserved

JIT3

5

Reserved

6

Reserved

7

Reserved

PS (Parameter Savable) bit
A Parameter Savable (PS) bit of one indicates that the drive is capable of saving the page in a nonvolatile vendor-specific location (used
only with MODE SENSE command).
PAGE CODE field
The PAGE CODE field is defined in SPC-4 and shall be set to the value defined in table 368.
PAGE LENGTH field
The PAGE LENGTH field specifies the length in bytes of the mode parameters that follow. If the initiator does not set this value to the value
that is returned for the page by the MODE SENSE command, the drive shall terminate the command with CHECK CONDITION status. The
sense key shall be set to ILLEGAL REQUEST with the additional sense code set to Invalid Field In Parameter List. See STRICT bit set to
0 description for exceptions.
PM (Performance Mode) bit
The PM (Performance Mode) bit is used to control the drive’s cache management algorithm to allow best performance in different types of
systems. It is the initiator’s responsibility to determine which setting is best for that system.
1

A PM value of 1 indicates that the number of cache segments is fixed to the value set in mode page 08h.

0

A PM value of 0 indicates that the drive will optimize the number of segments depending on the command activity observed by the
drive. The number of segments value (in mode page 08h) is ignored with the PM value is 0.

SSM (enable Synchronous Select Mode) bit
1

If the enable Synchronous Select Mode (SSM) bit equals one, the drive initiates WDTR and SDTR messages when it recognizes
that one may be required (after reset, reset message, or power cycle).

0

If the SSM bit equals zero, the drive does not initiate WDTR or SDTR regardless of negotiated conditions prior to reset, reset message, or power cycle.

IL (INQUIRY Length) bit
1

When the INQUIRY Length (IL) bit is set to 1, the standard INQUIRY data available to a host is limited to the 36 bytes required by
the SCSI-2 specification.

0

When the IL bit is reset (0), 148 bytes of standard INQUIRY data are available. The Additional Length field in byte 4 of the INQUIRY
data is updated to reflect the actual number of additional bytes available.

UNIT ATTENTION bit
1

When the UNIT ATTENTION bit is set to 1, then UNIT ATTENTION is logged in sense only; no CHECK CONDITION status is presented following any reset.

0

When this bit is Reset (0), then Check Condition is presented for all affected initiators following a reset until REQUEST SENSE is
issued by each initiator (as per current operation).

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DFUA (Disable Force Unit Access) bit
1

When the Disable Force Unit Access (DFUA) bit is set to 1, the drive ignores the FUA bit in READ and WRITE commands. This can
result in better drive performance in some circumstances.

0

When the DFUA is set to 0, the drive obeys the FUA setting in READ and WRITE commands.

ROUND bit
1

When the ROUND bit equals one, the drive treats and reports rounded parameters as described in 2.3.

0

When ROUND equals zero, the drive shall round the parameter and handle command completion reporting as if the parameter had
not been rounded.

STRICT bit
1

When the STRICT bit is a one, the drive checks for initiator attempts to change unchangeable parameters. If the drive detects an
attempt, it rejects the command in the standard way, i.e., CHECK CONDITION status from drive, REQUEST SENSE from the initiator, and Illegal Request Sense key (5h) back from the drive.

0

When the STRICT bit is zero, the drive ignores the values of the unchangeable parameters in a MODE SELECT command. The
drive does not reject the command trying to change unchangeable parameters or trying to send a mode page that is shorter than
the supported length.

Caution: Utilization of this forgiving option by a SCSI initiator port that does not analyze the impact of the truncation could
adversely affect data integrity.
SCSI-2 bit
1

When set to one, the SCSI-2 bit changes the following SCSI-3 features from their SCSI-3 definition to the SCSI-2 definition.

0

When S2 equals zero, the following features remain as specified in other portions of this specification:
a) Control Mode Page (0Ah) Length from 0Ah to 06h.
b) Caching Page (08h) Length from 12h to 0Ah.

DAR (Deferred Auto Reallocation) bit
1

Deferred reallocation is enabled. When an unrecoverable read error occurs, the drive remembers the LBA of the error; when a subsequent write command occurs for that LBA and the AWRE bit in mode page 1 is enabled, then the LBA is reallocated before the
write command is completed.

0

Deferred reallocation is disabled.

Self Seek bit
1

If the Self Seek bit is set to one, the drive will enter self seek mode for testing purposes. Such testing could include, but is not limited to, power dissipation and acoustics. While in this mode, the drive will accept SCSI commands and will process them in between
the self seek operations, including a MODE SELECT to turn this bit back off. As such, this bit should be off for normal drive operations.

0

If this bit is set to zero, the drive will not self seek; normal operating mode.

VJIT Disabled bit

1
0

When this bit is set to 1, the drive will always use the fastest seek type (i.e., JIT 0). JIT bits 0:3 of byte 4 are ignored.
When this bit is set to 0, the drive will operate according to the settings of JIT bits 0:3.

JIT (Just in Time) bits
The four JIT (Just In Time) bits allow you to enable and disable certain seek speeds. JIT0 represents the fastest seek type used by the
drive, JIT1 represents the second fastest, JIT2 represents the third fastest, and JIT3 represents the slowest seek type. You can use these
bits to reduce acoustics by disabling the fastest seeks. This can also reduce power consumption (from seek activity). These JIT settings
only affect user read and write operations. Background drive operations and user seek commands will always use the fastest seek type.
When the bit is set to 1, the drive is allowed to use this seek type and any slower seek types in its seek speed algorithm. When the bit is set
to 0, the drive is not allowed to use this seek type in its seek speed algorithm unless a faster seek type is selected. If all JIT bits are set to
zero or if all bits are set to one, the drive can use any of the seek speeds.
Reserved bits
These bits are reserved for future compatibility with Seagate host adapters. Though they presently may be changeable, these bits do not
control anything, unless the individual drive’s Product Manual, Volume 1, indicates that they do and defines their use in the MODE SENSE
Data section.
Reserved bytes
See individual drive’s Product Manual, Volume 1, MODE SENSE Data section for a table showing codes that indicate which of these bits
are changeable by the host using the MODE SELECT command.

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4.3.21

Verify Error Recovery mode page (07h)

The Verify Error Recovery mode page (see table 369) specifies the error recovery parameters the device server shall use during the
VERIFY command and the verify operation of the WRITE AND VERIFY command.
Table 369
Bit
Byte
0
1

Verify Error Recovery mode page
7

6

PS

SPF (0b)

Reserved

2
3
4
5
...
9
10
11

5

4

3

2

1

PAGE CODE (07h)
PAGE LENGTH (0Ah)
ERROR RECOVERY BITS
EER
PER
DTE
VERIFY RETRY COUNT
Obsolete

0

DCR

Reserved formerly
HEAD OFFSET COUNT (Byte 5), DATA STROBE OFFSET COUNT (Byte 6)
and WRITE RETRY COUNT (Byte 8) Bytes 7 and 9 were Reserved
(MSB)

VERIFY RECOVERY TIME LIMIT

(LSB)

PARAMETERS SAVEABLE (PS) bit
The parameters saveable (PS) bit, the subpage format (SPF) bit, the PAGE CODE field, the SUBPAGE CODE field, and the PAGE
LENGTH field are defined in 4.3.5.
EER bit, PER bit, DTE bit, and DCR bit
The EER bit, the PER bit, the DTE bit, and the DCR bit (i.e., the error recovery bits) are defined in 4.3.8. The combinations of these bits are
defined in table (see 4.3.8).
VERIFY RETRY COUNT field
The VERIFY RETRY COUNT field specifies the number of times that the device server shall attempt its recovery algorithm during a verify
operation.
VERIFY RECOVERY TIME LIMIT field
The VERIFY RECOVERY TIME LIMIT field specifies in milliseconds the maximum time duration that the device server shall use error
recovery procedures to recover data for an individual command. The device server may round this value as described in 2.3.
When both a retry count and a recovery time limit are specified, the one that requires the least time for data error recovery actions shall
have priority.
To disable all types of correction and retries the application client should set the EER bit to zero, the PER bit to one, the DTE bit to one, the
DCR bit to one, the VERIFY RETRY COUNT field to 00h, and the VERIFY RECOVERY TIME LIMIT field to 0000h.

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4.4

Vital product data parameters

4.4.1

Vital product data parameters overview and page codes

This subclause describes the vital product data (VPD) page structure and the VPD pages (see table 370) that are applicable to all SCSI
devices. These VPD pages are returned by an INQUIRY command with the EVPD bit set to one (see 3.6) and contain vendor specific
product information about a logical unit and SCSI target device. The vital product data may include vendor identification, product
identification, unit serial numbers, device operating definitions, manufacturing data, field replaceable unit information, and other vendor
specific information.
Table 370

Vital product data page codes

Page code

VPD Page Name

Reference

Support
Requirements

00h

Supported VPD Pages

4.4.16

Mandatory

01h - 7Fh

ASCII Information

4.4.2

Optional

80h

Unit Serial Number

4.4.17

Optional

81h

Obsolete

82h

Obsolete

83h

Device Identification

4.4.9

Mandatory

84h

Software Interface Identification

n/s

Optional

85h

Management Network Addresses

n/s

Optional

86h

Extended INQUIRY Data

4.4.7

Optional

87h

Mode Page Policy

4.4.12

Optional

88h

SCSI Ports

4.4.15

Optional

4.4.13

Optional

4.4.14

Optional

89h

Reserved

8Ah

Power Condition

8Bh

Reserved

8Ch

Reserved

8Dh

Power Consumption

8Eh - AFh

Reserved

B0h

Block Limits

4.4.4

Optional

B1h

Block Device Characteristics VPD page

4.4.3

Optional

4.4.11

Optional

B2h

Logical Block Provisioning VPD page

B3h - BFh

(See specific device type)

C0h

Firmware Numbers page

4.4.8

C1h

Date Code page

4.4.5

C2h

Jumper Settings page

4.4.10

C3h

Device Behavior page

4.4.6

C4h - FFh

Vendor specific

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4.4.2

ASCII Information VPD page (01h - 7Fh)

The ASCII Information VPD page (see table 371) contains information for the field replaceable unit code returned in the sense data (see
2.2.9).
Table 371
Bit
Byte
0
1
2
3
4
5
...
m
m+1
...
n

ASCII Information VPD page
7

6

5

PERIPHERAL QUALIFIER

4

3

2

1

0

PERIPHERAL DEVICE TYPE
PAGE CODE (01h - 7Fh)
Reserved
PAGE LENGTH (N-3)
ASCII LENGTH (M-4)

(MSB)
ASCII INFORMATION
(LSB)
Vendor specific information

PERIPHERAL QUALIFIER and the PERIPHERAL DEVICE TYPE fields
The PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field are defined in STANDARD INQUIRY DATA (see 3.6.2).
PAGE CODE field
The PAGE CODE field contains the same value as in the PAGE OR OPERATION CODE field of the INQUIRY CDB (see 3.6) and is associated with the FIELD REPLACEABLE UNIT CODE field returned in the sense data.
Note.

The FIELD REPLACEABLE UNIT CODE field in the sense data provides for 255 possible codes, while the PAGE CODE field provides for only 127 possible codes. For that reason it is not possible to return ASCII Information VPD pages for the upper code values.

PAGE LENGTH field
The PAGE LENGTH field specifies the length of the following VPD page data. The relationship between the PAGE LENGTH field and the
CDB ALLOCATION LENGTH field is defined in 2.2.6.
ASCII LENGTH field
The ASCII LENGTH field specifies the length in bytes of the ASCII INFORMATION field that follows. A value of zero in this field indicates
that no ASCII information is available for the specified page code. The relationship between the ASCII LENGTH field and the CDB ALLOCATION LENGTH field is defined in 2.2.6.
ASCII INFORMATION field
The ASCII INFORMATION field contains ASCII information concerning the field replaceable unit identified by the page code. The data in
this field shall be formatted in one or more character string lines. Each line shall contain only graphic codes (i.e., code values 20h through
7Eh) and shall be terminated with a NULL (00h) character.
VENDOR SPECIFIC INFORMATION field
The contents of the vendor specific information field is not defined in this manual.

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4.4.3

Block Device Characteristics VPD page (B1h)

The Block Device Characteristics VPD page (see table 372) contains parameters indicating characteristics of the logical unit.
Table 372
Bit
Byte
0
1
2
3
4
5
6
7
8
9
...
63

Block Device Characteristics VPD page
7

6

5

PERIPHERAL QUALIFIER
(MSB)

4

3

2

1

PERIPHERAL DEVICE TYPE
PAGE CODE (B1h)
PAGE LENGTH (003Ch)

(MSB)

(LSB)

MEDIUM ROTATION RATE

WABEREQ

0

PRODUCT TYPE
WACEREQ
Reserved

(LSB)
NOMINAL FORM FACTOR
VBULS

Reserved

PERIPHERAL QUALIFIER and PERIPHERAL DEVICE TYPE fields
The PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field are defined in SPC-4.
PAGE CODE and PAGE LENGTH fields
The PAGE CODE field and PAGE LENGTH field are defined in SPC-4 and shall be set to the values shown in Table 372.
MEDIUM ROTATION RATE field
The MEDIUM ROTATION RATE field is defined in Table 373.
Table 373

Medium Rotation Rate field

Code

Definition

0000h

Medium rotation rate is not reported

0001h

Non-rotating medium (e.g., solid state)

0002h to 0400h

Reserved

0401h to FFFEh

Nominal medium rotation rate in revolutions per minute
(e.g., 7 200 rpm = 1C20h,10 000 rpm = 2710h, and 15 000 rpm = 3A98h)
Reserved

FFFFh

PRODUCT TYPE field
The PRODUCT TYPE field (see table 374) defines the product type of the storage device.
Table 374

Product Type field

Code
00h
01 to EFh
F0h to FFh

Definition
Not indicated
Reserved
Not specified

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WABEREQ field
If a write medium operation has not been performed on a logical block referenced by a mapped LBA since a sanitize block erase operation
was performed, and no other error occurs during the processing of a read command specifying that LBA, then the write after block erase
required (WABEREQ) field indicates the device server behavior (see table 375).
Table 375
Code

WABEREQ field
Definition

00b

Not specified

01b

The device server completes the read command specifying that LBA with GOOD status and any data transferred
to the Data-In Buffer is indeterminate.

10b

The device server terminates the read command specifying that LBA with CHECK CONDITION status with sense
key set to MEDIUM ERROR and the additional sense code set to an appropriate value other than WRITE AFTER
SANITIZE REQUIRED (e.g., ID CRC OR ECC ERROR).

11b

The device server terminates the read command specifying that LBA with CHECK CONDITION status with sense
key set to MEDIUM ERROR and the additional sense code set to WRITE AFTER SANITIZE REQUIRED.

WACEREQ field
If a write medium operation has not been performed on a logical block referenced by a mapped LBA since a sanitize cryptographic erase
operation was performed, and no other error occurs during the processing of a read command specifying that LBA, then the write after
cryptographic erase required (WACEREQ) field indicates the device server behavior (see table 376).
Table 376
Code

WACEREQ field
Definition

00b

Not specified

01b

The device server completes the read command specifying that LBA with GOOD status and any data transferred
to the Data-In Buffer is indeterminate.

10b

The device server terminates the read command specifying that LBA with CHECK CONDITION status with sense
key set to MEDIUM ERROR and the additional sense code set to an appropriate value other than WRITE AFTER
SANITIZE REQUIRED (e.g., ID CRC OR ECC ERROR).

11b

The device server terminates the read command specifying that LBA with CHECK CONDITION status with sense
key set to MEDIUM ERROR and the additional sense code set to WRITE AFTER SANITIZE REQUIRED.

NOMINAL FORM FACTOR field
The NOMINAL FORM FACTOR field indicates the nominal form factor of the device containing the logical unit and is defined in Table 377.
Table 377

Nominal Form Factor Field

Code

Definition

0h

Nominal form factor is not reported

1h

5.25 inch

2h

3.5 inch

3h

2.5 inch

4h

1.8 inch

5h

Less than 18 inch

All others

Reserved

VBULS bit
1

A verify byte check unmapped LBA supported (VBULS) bit set to one indicates that the device server supports unmapped LBAs
while processing VERIFY commands (see 3.55, 3.56, 3.57, and 3.58) and WRITE AND VERIFY commands (see 3.64, 3.65, 3.66,
and 3.67) with the BYTCHK field set to 01b.

0

A VBULS bit set to zero indicates that the device server does not support unmapped LBAs while processing VERIFY commands
and WRITE AND VERIFY commands with the BYTCHK field set to 01b.

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4.4.4

Block Limits VPD page (B0h)

The Block Limits VPD page (see table 378) provides the application client with the means to obtain certain operating parameters of the
logical unit.
Table 378
Bit
Byte
0
1
2
3
4
5
6
7
8
...
11
12
...
15
16
...
19
20
...
23
24
...
27
28
...
31
32
...
35
36
...
43
44
...
63

Block Limits VPD page
7

6

5

PERIPHERAL QUALIFIER
(MSB)

4

3

2

1

PERIPHERAL DEVICE TYPE
PAGE CODE (B0h)
PAGE LENGTH (003Ch)

Reserved
MAXIMUM COMPARE AND WRITE LENGTH
(MSB)

0

OPTIMAL TRANSFER LENGTH GRANULARITY

(LSB)
WSZN

(LSB)

(MSB)
MAXIMUM TRANSFER LENGTH
(LSB)
(MSB)
OPTIMAL TRANSFER LENGTH
(LSB)
(MSB)
MAXIMUM PREFETCH LENGTH
(LSB)
(MSB)
MAXIMUM UNMAP LBA COUNT
(LSB)
(MSB)
MAXIMUM UNMAP BLOCK DESCRIPTOR COUNT
(LSB)
(MSB)
OPTIMAL UNMAP GRANULARITY
(LSB)
UGAVALID

(MSB)
UNMAP GRANULARITY ALIGNMENT
(LSB)

(MSB)
MAXIMUM WRITE SAME LENGTH
(LSB)
Reserved

PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field
The PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field are defined in SPC-4.
PAGE CODE field and PAGE LENGTH field
The PAGE CODE field and PAGE LENGTH field are defined in SPC-4 and shall be set to the values shown in table 378 for the Block Limits
VPD page.
WSNZ bit
1

A write same non-zero (WSNZ) bit set to one indicates that the device server does not support a value of zero in the NUMBER OF
LOGICAL BLOCKS field in the WRITE SAME command CDBs (see 3.71, 3.72, and 3.73).

0

A WSNZ bit set to zero indicates that the device server may or may not support a value of zero in the NUMBER OF LOGICAL
BLOCKS field of the WRITE SAME commands.

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MAXIMUM COMPARE AND WRITE LENGTH field
A MAXIMUM COMPARE AND WRITE LENGTH field set to a non-zero value indicates the maximum value that the device server accepts
in the NUMBER OF LOGICAL BLOCKS field in the COMPARE AND WRITE command (see SBC-3). A MAXIMUM COMPARE AND
WRITE LENGTH field set to zero indicates that the device server does not support the COMPARE AND WRITE command. The device
server shall set the MAXIMUM COMPARE AND WRITE LENGTH field to a value less than or equal to the value in the MAXIMUM TRANSFER LENGTH field.
OPTIMAL TRANSFER LENGTH GRANULARITY field
The OPTIMAL TRANSFER LENGTH GRANULARITY field set to a non-zero value indicates the optimal transfer length granularity size in
logical blocks for a single command shown in the command column of table 211. If a device server receives one of these commands with
a transfer size that is not equal to a multiple of this value, then the device server may incur significant delays in processing the command.
An OPTIMAL TRANSFER LENGTH GRANULARITY field set to 0000_0000h indicates that the device server does not report optimal
transfer length granularity.
Table 379

Error history BUFFER ID field
Field that specifies
the transfer size

Block Limits VPD page
field(s) that indicate
maximum limits

CDB NUMBER OF
LOGICAL BLOCKS field

MAXIMUM COMPARE AND
WRITE LENGTH field

ORWRITE (16) / (32)

CDB TRANSFER
LENGTH field

MAXIMUM TRANSFER
LENGTH field

PREFETCH (10) / (16)

CDB PREFETCH
LENGTH field

MAXIMUM PREFETCH
LENGTH field

READ (10) / (12) / (16) / (32)

CDB TRANSFER
LENGTH field

Command
COMPARE AND WRITE

VERIFY (10) / (12) / (16) / (32)

CDB VERIFICATION
LENGTH field

WRITE (10) / (12) / (16) / (32)
READ (10) / (12) / (16) / (32)
XDWRITEREAD (10) / (32)

Additional sense code if the
value in the specified field
exceeds the maximum limit

INVALDIN FIELD IN CDB
MAXIMUM TRANSFER
LENGTH field

CDB TRANSFER
LENGTH field

XPWRITE (10) / (32)
Any individual block device range
descriptor in a POPULATE TOKEN
command (see 5.7)
Any individual block device range
descriptor in a WRITE USING
TOKEN command (see 5.46)

Block device range
descriptor NUMBER
OF LOGICAL BLOCKS
field

MAXIMUM TRANSFER
LENGTH field

INVALID FIELD IN
PARAMETER LIST

MAXIMUM TRANSFER LENGTH field
The MAXIMUM TRANSFER LENGTH field set to a non-zero value indicates the maximum transfer length in logical blocks that the device
server accepts for a single command shown in table 379. If a device server receives one of these commands with a transfer size greater
than this value, then the device server shall terminate the command with CHECK CONDITION status with the sense key set to ILLEGAL
REQUEST and the additional sense code set to the value shown in table 379. A MAXIMUM TRANSFER LENGTH field set to 0000_0000h
indicates that the device server does not report a limit on the transfer length.
OPTIMAL TRANSFER LENGTH field
The OPTIMAL TRANSFER LENGTH field set to a non-zero value indicates the optimal transfer size in logical blocks for a single command
shown in table 379. If a device server receives one of these commands with a transfer size greater than this value, then the device server
may incur significant delays in processing the command. An OPTIMAL TRANSFER LENGTH field set to 0000_0000h indicates that the
device server does not report an optimal transfer size.

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MAXIMUM PREFETCH LENGTH field
The MAXIMUM PREFETCH LENGTH field indicates the maximum prefetch length in logical blocks that the device server accepts for a single PRE-FETCH command. The device server should set the MAXIMUM PREFETCH LENGTH field to less than or equal to the MAXIMUM TRANSFER LENGTH field.
MAXIMUM UNMAP LBA COUNT field
The MAXIMUM UNMAP LBA COUNT field set to a non-zero value indicates the maximum number of LBAs that may be unmapped by an
UNMAP command (see 3.54). If the number of LBAs that may be unmapped by an UNMAP command is constrained only by the amount of
data that may be contained in the UNMAP parameter list (see 3.54.2), then the device server shall set the MAXIMUM UNMAP LBA
COUNT field to FFFF_FFFFh. If the device server implements the UNMAP command, then the value in this field shall be greater than or
equal to one. A MAXIMUM UNMAP LBA COUNT field set to 0000_0000h indicates that the device server does not implement the UNMAP
command.
MAXIMUM UNMAP BLOCK DESCRIPTOR COUNT field
The MAXIMUM UNMAP BLOCK DESCRIPTOR COUNT field set to a non-zero value indicates the maximum number of UNMAP block
descriptors (see 3.54.2) that shall be contained in the parameter data transferred to the device server for an UNMAP command (see 3.54).
If there is no limit on the number of UNMAP block descriptors contained in the parameter data, then the device server shall set the MAXIMUM UNMAP BLOCK DESCRIPTOR COUNT field to FFFF_FFFFh. If the device server implements the UNMAP command, then the
value in the MAXIMUM UNMAP BLOCK DESCRIPTOR COUNT field shall be greater than or equal to one. A MAXIMUM UNMAP BLOCK
DESCRIPTOR COUNT field set to 0000_0000h indicates that the device server does not implement the UNMAP command.
OPTIMAL UNMAP GRANULARITY field
The OPTIMAL UNMAP GRANULARITY field set to a non-zero value indicates the optimal granularity in logical blocks for unmap requests
(e.g., an UNMAP command or a WRITE SAME (16) command with the UNMAP bit set to one). An unmap request with a number of logical
blocks that is not a multiple of this value may result in unmap operations on fewer LBAs than requested. An OPTIMAL UNMAP GRANULARITY field set to 0000_0000h indicates that the device server does not report an optimal unmap granularity.
UGVALID bit
1

An UGVALID (unmap granularity alignment valid) bit set to one indicates that the UNMAP GRANULARITY ALIGNMENT field is
valid.

0

A UGAVALID bit set to zero indicates that the UNMAP GRANULARITY ALIGNMENT field is not valid.

UNMAP GRANULARITY ALIGNMENT field
The UNMAP GRANULARITY ALIGNMENT field indicates the LBA of the first logical block to which the OPTIMAL UNMAP GRANULARITY
field applies. The unmap granularity alignment is used to calculate an optimal unmap request starting LBA as follows:
optimal unmap request starting LBA = (n × optimal unmap granularity) + unmap granularity alignment
where:
n

is zero or any positive integer value;

optimal unmap granularity

is the value in the OPTIMAL UNMAP GRANULARITY field; and

unmap granularity alignment

is the value in the UNMAP GRANULARITY ALIGNMENT field.

An unmap request with a starting LBA that is not optimal may result in unmap operations on fewer LBAs than requested.
MAXIMUM WRITE SAME LENGTH field
A MAXIMUM WRITE SAME LENGTH field set to a non-zero value indicates the maximum value that the device server accepts in the
NUMBER OF LOGICAL BLOCKS field for a WRITE SAME command. A MAXIMUM WRITE SAME LENGTH field set to zero indicates that
the device server does not report a limit on the number of logical blocks that may be requested for a single WRITE SAME command.

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4.4.5

Date Code page (C1h)

Table 380
Bit
Byte
0

ETF Log Date Code page (C1h)
7

6

PERIPHERAL
QUALIFIER

5

4

3

PAGE CODE (C1h)

2

00h

3

PAGE LENGTH (10h)

0

(MSB)
ETF LOG DATE IN ASCII

...

(LSB)

11
12

1

PERIPHERAL DEVICE TYPE

1

4

2

(MSB)

...

COMPILE DATE CODE

19

(LSB)

PERIPHERAL QUALIFIER field and PERIPHERAL DEVICE TYPE field
The PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field are defined in STANDARD INQUIRY DATA (see 3.6.2).
PAGE CODE field
The PAGE CODE field shall be set to the value defined in table 380.
PAGE LENGTH field
The PAGE LENGTH field specifies the length of the following VPD page data. The relationship between the PAGE LENGTH field and the
CDB ALLOCATION LENGTH field is defined in 2.2.6.
ETF Log field
The ETF Log date code field contains ASCII data. The data is stored in the format MMDDYYYY. Leading ASCII zero characters are added
to single-digit months or days.
COMPILE DATE CODE field
The COMPILE DATE CODE field contains 8 ASCII bytes of data for a date of the form MMDDYYYY.

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4.4.6

Device Behavior page (C3h)

The Device Behavior page (see table ) will be used by the regression tests to determine what behavior should be expected from a
particular firmware package.
Table 381
Bit
Byte
0

Device Behavior page (C3h)
7

6

5

4

3

PERIPHERAL QUALIFIER

1

0

PERIPHERAL DEVICE TYPE

1

PAGE CODE (C3h)

2

Reserved

3

PAGE LENGTH

4

VERSION NUMBER

5

BEHAVIOR CODE

6

BEHAVIOR CODE VERSION NUMBER

7
...

2

ASCII FAMILY NUMBER (16 bytes)

22
23

NUMBER OF INTERLEAVES

24

DEFAULT NUMBER OF CACHE SEGMENTS

25+

Feature Flags and Additional Byte Fields will go here but are undefined at this time.

PERIPHERAL QUALIFIER field and PERIPHERAL DEVICE TYPE fields
The PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field are defined in STANDARD INQUIRY DATA (see 3.6.2).
PAGE CODE field
The PAGE CODE field shall be set to the value defined in table 381.
PAGE LENGTH field
PAGE LENGTH defines the length of the Device Behavior information in bytes. If the ALLOCATION LENGTH is too small to transfer all of
the page, the page length shall not be adjusted to reflect the truncation.
VERSION NUMBER field
The VERSION NUMBER is a one-byte short form notation for the 24-byte assignment in the Firmware Numbers page. Version Numbers
are registered by Engineering services.
BEHAVIOR CODE and BEHAVIOR CODE VERSION NUMBER fields
The BEHAVIOR CODE and BEHAVIOR CODE VERSION NUMBER are jointly assigned by the Firmware Engineering Managers of all
SCSI design locations.
ASCII FAMILY NUMBER field
The ASCII FAMILY NUMBER field contains the drive model number. The data is left-aligned within this field.
NUMBER OF INTERLEAVES field
The NUMBER OF INTERLEAVES field indicates the number of data interleaves used by the ECC correction algorithm.
DEFAULT NUMBER OF CACHE SEGMENTS field
The DEFAULT NUMBER OF CACHE SEGMENTS field gives the number of segments into which the host requests the drive divide the
cache.

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4.4.7

Extended INQUIRY Data VPD page (86h)

The Extended INQUIRY Data VPD page (see table 382) provides the application client with a means to obtain information about the logical
unit.
Table 382
Bit
Byte
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
...
63

Extended INQUIRY Data VPD page
7

6

5

PERIPHERAL QUALIFIER
(MSB)

4

3

2

1

0

PERIPHERAL DEVICE TYPE
PAGE CODE (86h)
PAGE LENGTH (3Ch)

(LSB)
GRD_CHK APP_CHK REF_CHK
PRIOR_SUP HEADSUP
ORDSUP
SIMPSUP
WU_SUP
CRD_SUP
NV_SUP
V_SUP
Reserved
LUICLR = 1
Reserved
CBCS
MULTI I_T NEXUS MICROCODE DOWNLOAD

ACTIVATE MICROCODE
SPT
Reserved
UASK_SUP GROUP_SUP
Reserved
Reserved
P_I_I_SUP
Reserved
R_SUP
Reserved
(MSB)
EXTENDED SELF-TEST COMPLETION MINUTES
POA_SUP

HRA_SUP

(LSB)

VSA_SUP
Reserved
MAXIMUM SUPPORTED SENSE DATA LENGTH
Reserved

PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field
The PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field are defined in STANDARD INQUIRY DATA (see 3.6.2).
PAGE CODE field
The PAGE CODE field shall be set to the value defined in table 382.
PAGE LENGTH field
The PAGE LENGTH field specifies the length of the following VPD page data and shall be set to 60. The relationship between the PAGE
LENGTH field and the CDB ALLOCATION LENGTH field is defined in 2.2.6.

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ACTIVATE MICROCODE field
The ACTIVATE MICROCODE field (see table 383) indicates how a device server activates microcode and establishes a unit attention condition when a WRITE BUFFER command (see 3.68) with the download microcode mode set to 05h or 07h is processed (see 3.68.5).
Table 383
Value

ACTIVATE MICROCODE field
Meaning

00b

The actions of the device server may or may not be as defined for values 01b or 10b.

01b

The device server:
1) activates the microcode before completion of the final command in the WRITE BUFFER sequence; and
2) establishes a unit attention condition for the initiator port associated with every I_T nexus, except the
I_T nexus on which the WRITE BUFFER command was received, with the additional sense code set to
MICROCODE HAS BEEN CHANGED.

10b

The device server:
1) activates the microcode after:
A) a vendor specific event;
B) a power on event; or
C) a hard reset event;
and
2) establishes a unit attention condition for the initiator port associated with every I_T nexus with the additional sense code set to MICROCODE HAS BEEN CHANGED.

11b

Reserved.

SPT (Supported Protection Type) field
A supported protection type (SPT) field (see table 384) indicates the type of protection the logical unit supports. The SPT field shall be
ignored if the PROTECT bit is set to zero.
Table 384

SPT field

Code

Definition

000b

The logical unit supports type 1 protection (see SBC-3).

001b

The logical unit supports type 2 protection (see SBC-3).

010b

Reserved

011b

The logical unit supports type 3 protection (see SBC-3).

100b - 111b

Reserved

GRD_CHK (Guard Check) bit
0

A guard check (GRD_CHK) bit set to zero indicates that the device server does not check the LOGICAL BLOCK GUARD field in
the protection information (see SBC-3), if any.

1

A GRD_CHK bit set to one indicates that the device server checks the LOGICAL BLOCK GUARD field in the protection information,
if any.

APP_CHK (Application Tag Check) bit
0

An application tag check (APP_CHK) bit set to zero indicates that the device server does not check the LOGICAL BLOCK APPLICATION TAG field in the protection information (see SBC-3), if any.

1

An APP_CHK bit set to one indicates that the device server checks the LOGICAL BLOCK APPLICATION TAG field in the protection
information, if any.

REF_CHK (Reference Tag Check) bit
0

A reference tag check (REF_CHK) bit set to zero indicates that the device server does not check the LOGICAL BLOCK REFERENCE TAG field in the protection information (see SBC-3), if any.

1

A REF_CHK bit set to one indicates that the device server checks the LOGICAL BLOCK REFERENCE TAG field in the protection
information, if any.

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UASK_SUP (Unit Attention Sense Key Supported) bit
1

A unit attention condition sense key specific data supported (UASK_SUP) bit set to one indicates that the device server returns
sense-key specific data for the UNIT ATTENTION sense key (see 2.4.1.1.4.6).

0

A UASK_SUP bit set to zero indicates that the device server does not return sense-key specific data for the UNIT ATTENTION
sense key.

GROUP_SUP (Grouping Function Supported) bit
1

A grouping function supported (GROUP_SUP) bit set to one indicates that the grouping function (see SBC-3) is supported by the
device server.

0

A GROUP_SUP bit set to zero indicates that the grouping function is not supported.

PRIOR_SUP (Priority Supported) bit
1

A priority supported (PRIOR_SUP) bit set to one indicates that task priority (see SAM-5) is supported by the logical unit.

0

A PRIOR_SUP bit set to zero indicates that task priority is not supported.

HEADSUP (Head of Queue Supported) bit
1

A head of queue supported (HEADSUP) bit set to one indicates that the HEAD OF QUEUE task attribute (see SAM-5) is supported
by the logical unit.

0

A HEADSUP bit set to zero indicates that the HEAD OF QUEUE task attribute is not supported. If the HEADSUP bit is set to zero,
application clients should not specify the HEAD OF QUEUE task attribute as an Execute Command procedure call argument.

ORDSUP (Ordered Supported) bit
1

An ordered supported (ORDSUP) bit set to one indicates that the ORDERED task attribute (see SAM-5) is supported by the logical
unit.

0

An ORDSUP bit set to zero indicates that the ORDERED task attribute is not supported. If the ORDSUP bit is set to zero, application clients should not specify the ORDERED task attribute as an Execute Command procedure call argument.

SIMPSUP (Simple Supported) bit
1

A simple supported (SIMPSUP) bit set to one indicates that the SIMPLE task attribute (see SAM-5) is supported by the logical unit.
Logical units that support the full task management model (see SAM-5) shall set the SIMPSUP bit to one.

0

A SIMPSUP bit set to zero indicates that the SIMPLE task attribute is not supported. If the SIMPSUP bit is set to zero, application
clients should not specify the SIMPLE task attribute as an Execute Command procedure call argument.

Note.

SAM-5 defines how unsupported task attributes are processed.

WU_SUP bit
0

A write uncorrectable supported (WU_SUP) bit set to zero indicates that the device server does not support application clients setting the WR_UNCOR bit to one in the WRITE LONG command (see 3.70).

1

A WU_SUP bit set to one indicates that the device server supports application clients setting the WR_UNCOR bit to one in the
WRITE LONG command.

CRD_SUP bit
0

A correction disable supported (CRD_SUP) bit set to zero indicates that the device server does not support application clients setting the COR_DIS bit to one in the WRITE LONG command (see 3.70).

1

A CRD_SUP bit set to one indicates that the device server supports application clients setting the COR_DIS bit to one in the
WRITE LONG command.

NV_SUP bit
1

An NV_SUP bit set to one indicates that the device server supports a non-volatile cache and that the applicable command standard
defines features using this cache (e.g., the FUA_NV bit in SBC-3).

0

An NV_SUP bit set to zero indicates that the device server may or may not support a non-volatile cache.

V_SUP bit
1

A V_SUP bit set to one indicates that the device server supports a volatile cache and that the applicable command standard
defines features using this cache (e.g., the FUA bit in SBC-3).

0

An V_SUP bit set to zero indicates that the device server may or may not support a volatile cache.

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P_I_I_SUP bit
1

A protection information interval supported (P_I_I_SUP) bit set to one indicates that the logical unit supports protection information
intervals (see SBC-3).

0

A P_I_I_SUP bit set to zero indicates that the logical unit does not support protection information intervals.

LUICLR bit
1

A logical unit I_T nexus clear (LUICLR) bit set to one indicates the SCSI target device clears any unit attention condition with an
additional sense code of REPORTED LUNS DATA HAS CHANGED in each logical unit accessible to an I_T nexus after reporting
the unit attention condition for any logical unit over that I_T nexus (see SAM-5).

0

An LUICLR bit set to zero indicates the SCSI target device clears unit attention conditions as defined in SPC-3.

The LUICLR bit shall be set to one.
R_SUP bit
0

A referrals supported (R_SUP) bit set to zero indicates that the device server does not support referrals (see SBC-3).

1

An R_SUP bit set to one indicates that the device server supports referrals.

CBCS bit
1

A capability-based command security (CBCS) bit set to one indicates that the logical unit supports the capability- based command
security technique (see SPC-4).

0

A CBCS bit set to zero indicates that the logical unit does not support the capability-based command security technique.

MULTI I_T NEXUS MICROCODE DOWNLOAD field
The MULTI I_T NEXUS MICROCODE DOWNLOAD field (see table 59 in 5.4) indicates how the device server handles concurrent attempts
to download microcode using the WRITE BUFFER command (see 5.4) from multiple I_T nexuses.
EXTENDED SELF-TEST COMPLETION MINUTES field
The EXTENDED SELF-TEST COMPLETION MINUTES field contains advisory data that is the time in minutes that the device server
requires to complete an extended self-test provided the device server is not interrupted by subsequent commands and no errors occur
during processing of the self-test. The application client should expect the self-test completion time to exceed the value in this field if other
commands are sent to the logical unit while a self-test is in progress or if errors occur during the processing of the self-test. If a device
server supports SELF-TEST CODE field values other than 000b for the SEND DIAGNOSTIC command (see 6.42) and the self-test
completion time is greater than 18 hours, then the device server shall support the EXTENDED SELF-TEST COMPLETION MINUTES field.
A value of 0000h indicates that the EXTENDED SELF-TEST COMPLETION MINUTES field is not supported. A value of FFFFh indicates
that the extended self-test takes 65 535 minutes or longer.
POA_SUP bit
1

A power on activation supported (POA_SUP) bit set to one indicates that the device server supports a WRITE BUFFER command
with the MODE field set to 0Dh (see 6.49.10) and the PO_ACT bit set to one.

0

A POA_SUP bit set to zero indicates that the device server does not support a WRITE BUFFER command with the MODE field set
to 0Dh and the PO_ACT bit set to one.

HRA_SUP bit
1

A hard reset activation supported (HRA_SUP) bit set to one indicates that the device server supports a WRITE BUFFER command
with the MODE field set to 0Dh (see 6.49.10) and the HR_ACT bit set to one.

0

A HRA_SUP bit set to zero indicates that the device server does not support a WRITE BUFFER command with the MODE field set
to 0Dh and the HR_ACT bit set to one.

VSA_SUP bit
1

A vendor specific activation supported (VSA_SUP) bit set to one indicates that the device server supports a WRITE BUFFER command with the MODE field set to 0Dh (see 6.49.10) and the VSE_ACT bit set to one.

0

A VSA_SUP bit set to zero indicates that the device server does not support a WRITE BUFFER command with the MODE field set
to 0Dh and the VSE_ACT bit set to one.

MAXIMUM SUPPORTED SENSE DATA LENGTH field
The MAXIMUM SUPPORTED SENSE DATA LENGTH field indicates the maximum length in bytes of sense data (see 4.5) that the device
server is capable of returning in the same I_T_L_Q nexus transaction as the status. A MAXIMUM SUPPORTED SENSE DATA LENGTH
field set to zero indicates that the device server does not report a maximum length. This value shall be less than or equal to 252.

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4.4.8

Firmware Numbers page (C0h)

Table 385
Bit
Byte
0

Firmware Numbers page (C0h)
7

6

5

PERIPHERAL
QUALIFIER

4

3

2

1

0

PERIPHERAL DEVICE TYPE

1

PAGE CODE (C0h)

2

00h

3

PAGE LENGTH

4
...

SCSI FIRMWARE RELEASE NUMBER

11
12
...

SERVO FIRMWARE RELEASE NUMBER

19
20
...

SAP BLOCK POINT NUMBERS (MAJOR/MINOR)

27
28
...

SERVO FIRMWARE RELEASE DATE

31
32
...

SERVO ROM RELEASE DATE

35
36
...

SAP FIRMWARE RELEASE NUMBER

43
44
...

SAP FIRMWARE RELEASE DATE

47
48
...

SAP FIRMWARE RELEASE YEAR

51
52
...

SAP MANUFACTURING KEY

55
56
...

SERVO FIRMWARE PRODUCT FAMILY AND PRODUCT FAMILY MEMBER IDs

59

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PERIPHERAL QUALIFIER field and PERIPHERAL DEVICE TYPE fields
The PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field are defined in STANDARD INQUIRY DATA (see 3.6.2).
PAGE CODE field
The PAGE CODE field shall be set to the value defined in table 385.
PAGE LENGTH field
The PAGE LENGTH field specifies the length of the following VPD page data. The relationship between the PAGE LENGTH field and the
CDB ALLOCATION LENGTH field is defined in 2.2.6.
SCSI FIRMWARE RELEASE NUMBER field
The SCSI FIRMWARE RELEASE NUMBER fields contain ASCII data. The least significant ASCII character of the Drive firmware number
shall appear as the last byte of the field.
SERVO FIRMWARE RELEASE NUMBER field
The SERVO FIRMWARE RELEASE NUMBER fields contain ASCII data. The least significant ASCII character of the Drive firmware number shall appear as the last byte of the field.
SAP BLOCK POINT NUMBERS (MAJOR/MINOR)
This field contains the Servo Adaptive Parameter Block Point Number.
SERVO FIRMWARE RELEASE DATE field
Servo Firmware Release Date indicates the date of the firmware release.
SERVO ROM RELEASE DATE field
Servo ROM Release Date indicates the date of the ROM release.
SAP FIRMWARE RELEASE NUMBER field, SAP FIRMWARE RELEASE DATE field, and SAP FIRMWARE RELEASE YEAR field
These fields are created independently from the servo firmware. These fields contain ASCII data.
SAP MANUFACTURING KEY field
The SAP MANUFACTURING KEY field contains a binary code used by manufacturing to identify the SAP.
SERVO FIRMWARE PRODUCT FAMILY and PRODUCT FAMILY MEMBER IDs field
The high order word of the SERVO FIRMWARE PRODUCT FAMILY and PRODUCT FAMILY MEMBER IDs field contains a binary code
which corresponds to the Servo Firmware Family ID. The low order word of this field contains a binary code which corresponds to the
Product Family Member ID.
Note.

Applies to model families that return 60 bytes rather than 35 or 28.

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4.4.9

Device Identification VPD page (83h)

The Device Identification VPD page (see table ) provides the means to retrieve zero or more identification descriptors applying to the
logical unit. Logical units may have more than one identification descriptor (e.g., if several types or associations of identifier are supported).
Device identifiers consist of one or more of the following:
• Logical unit names;
• SCSI target port identifiers;
• SCSI target port names;
• SCSI target device names;
• Relative target port identifiers;
• SCSI target port group number; or
• Logical unit group number.
Identification descriptors shall be assigned to the peripheral device (e.g., a disk drive) and not to the currently mounted media, in the case
of removable media devices. Operating systems are expected to use the identification descriptors during system configuration activities to
determine whether alternate paths exist for the same peripheral device.
Table 386
Bit
Byte
0

Device Identification VPD page
7

6

5

PERIPHERAL QUALIFIER

3

2

1

0

PERIPHERAL DEVICE TYPE
PAGE CODE (83h)

1
2

4

MSB

PAGE LENGTH (n-3)

3

LSB

Identification descriptor list
4

Identification Descriptor (first) (see table 387)

...
...

Identification Descriptor (last) (see table 387)

n
PERIPHERAL QUALIFIER and the PERIPHERAL DEVICE fields
The PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field are defined in STANDARD INQUIRY DATA (see 3.6.2).
PAGE CODE field
The PAGE CODE field shall be set to the value defined in table .
PAGE LENGTH field
The PAGE LENGTH field specifies the length of the following VPD page data. The relationship between the PAGE LENGTH field and the
CDB ALLOCATION LENGTH field is defined in 2.2.6.

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Identification Descriptor field
Each IDENTIFICATION DESCRIPTOR (see Table 387) contains information identifying the logical unit, physical device, or access path
used by the command and returned parameter data.
Table 387

Identification Descriptor

Bit
Byte

7

6

5

4

3

2

PROTOCOL IDENTIFIER

0
PIV

1

Reserved

1

0

CODE SET

ASSOCIATION

IDENTIFIER TYPE

2

Reserved

3

IDENTIFIER LENGTH (n – 3)

4
IDENTIFIER

...
n
PROTOCOL IDENTIFIER field

The PROTOCOL IDENTIFIER field may indicate the SCSI transport protocol to which identification descriptor applies. If the ASSOCIATION field contains a value other than 1h or 2h or the PIV bit is set to zero, then the PROTOCOL IDENTIFIER field should be ignored. If
the ASSOCIATION field contains a value of 1h or 2h and the PIV bit is set to one, then the PROTOCOL IDENTIFIER field shall contain one
of the values shown in table 238 (see 7.5.1) to indicate the SCSI transport protocol to which identification descriptor applies.
CODE SET field
The CODE SET field specifies the code set used for the identifier field, as described in Table . This field is intended to be an aid to software
that displays the identifier field.
Table 388

Code set field

Value

Description

0h

Reserved

1h

The IDENTIFIER field shall contain binary values

2h

The IDENTIFIER field shall contain ASCII graphic codes (i.e., code values 20h through 7Eh)

3h - Fh

Reserved

PIV (Protocol Identifier Valid) bit
0

A protocol identifier valid (PIV) bit of zero indicates the PROTOCOL IDENTIFIER field should be ignored. If the ASSOCIATION field
contains a value of 1h or 2h then a PIV bit set to one indicates the PROTOCOL IDENTIFIER field contains a valid protocol identifier
selected from the values shown in table 389. If the ASSOCIATION field contains a value other than 1h or 2h then the PIV bit should
be ignored.

Table 389

PROTOCOL IDENTIFIER values

Protocol Identifier

Description

Protocol Standard

0h

Fibre Channel

FCP-2

1h

Parallel SCSI

SPI-4

2h

SSA

SSA-S3P

3h

IEEE 1394

SBP-2

4h

Remote Direct Memory Access (RDMA)

SRP

5h

Internet SCSI

iSCSI

6h

SAS Serial SCSI Protocol

SAS

7h - Fh

Reserved

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ASSOCIATION field
The ASSOCIATION field indicates the entity that the Identification descriptor describes. If a physical or logical device returns an Identification descriptor with the ASSOCIATION field set to 0h, it shall return the same descriptor when it is accessed through any other path.
The ASSOCIATION field specifies the entity with which the Identifier field is associated, as described in Table 390.
Table 390
Value

ASSOCIATION field
Description

0h

The IDENTIFIER field is associated with the addressed physical or logical device

1h

The IDENTIFIER field is associated with the port that received the request

2h

The IDENTIFIER field is associated with the SCSI target device that contains the addressed logical unit.

‘3h

Reserved

IDENTIFIER TYPE field
The IDENTIFIER TYPE field specifies the format and assignment authority for the identifier, as described in tables 391 and 392.
Table 391
Value

IDENTIFIER Type field
Description

0h

No assignment authority was used and consequently there is no guarantee that the identifier is globally unique
(i.e., the identifier is vendor specific).

1h

The first 8 bytes of the IDENTIFIER field are a Vendor ID (see annex C). The organization associated with the
Vendor ID is responsible for ensuring that the remainder of the identifier field is unique. One recommended
method of constructing the remainder of the identifier field is to concatenate the product identification field from
the standard INQUIRY data field and the product serial number field from the unit serial number page.

2h

The IDENTIFIER field contains a Canonical form IEEE Extended Unique Identifier, 64-bit (EUI-64). In this case,
the identifier length field shall be set to 8. Note that the IEEE guide-lines for EUI-64 specify a method for unambiguously encapsulating an IEEE 48-bit identifier within an EUI-64.

3h

The IDENTIFIER field contains an FC-PH, FC-PH3 or FC-FS Name_Identifier. Any FC-PH, FC-PH3 or FC-FS
identifier may be used, including one of the four based on a Canonical form IEEE company_id.

4h

If the ASSOCIATION field contains 1h, the Identifier value contains a four-byte binary number identifying the
port relative to other ports in the device using the values shown Table 390. The CODE SET field shall be set to
1h and the IDENTIFIER LENGTH field shall be set to 4h. If the ASSOCIATION field does not contain 1h, use of
this identifier type is reserved.

5h

If the Association value is 1h, the Identifier value contains a four-byte binary number identifying the port relative
to other ports in the device using the values shown Table 390. The CODE SET field shall be set to 1h and the
IDENTIFIER LENGTH field shall be set to 4h. If the ASSOCIATION field does not contain 1h, use of this identifier type is reserved.

6h

If the ASSOCIATION value is 0h, the IDENTIFIER value contains a four-byte binary number identifying the port
relative to other ports in the device using the values shown Table 390. The CODE SET field shall be set to 1h
and the IDENTIFIER LENGTH field shall be set to 4h. If the ASSOCIATION field does not contain 0h, use of
this identifier type is reserved.

7h

The MD5 logical unit identifier shall not be used if a logical unit provides unique identification using identifier
types 2h or 3h. A bridge device may return a MD5 logical unit identifier type for that logical unit that does not
support the Device Identification VPD page.

8h - Fh

Reserved.

IDENTIFIER LENGTH field
The IDENTIFIER LENGTH field specifies the length in bytes of the IDENTIFIER field. If the ALLOCATION LENGTH field of the command
descriptor block is too small to transfer all of the identifier, the identifier length shall not be adjusted to reflect the truncation.

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IDENTIFIER field
The IDENTIFIER field contains the identifier as described by the Association, Identifier Type, CODE SET, and IDENTIFIER LENGTH
fields. The example described in this clause and shown in Table 392 is not a normative part of this manual. This example of a complete
device identification VPD page assumes that the product is a direct-access device with an T10 Vendor ID of “XYZ_Corp,” a product identification of “Super Turbo Disk,” and a product serial number of “2034589345.” Furthermore, it is assumed that the manufacturer has been
assigned a 24-bit IEEE company_id of 01ABCDh by the IEEE Registration Authority Committee and that the manufacture has assigned a
24-bit extension_identifier of 234567h to this logical unit. The combined 48-bit identifier is reported in the 64-bit format as defined by the
IEEE 64-bit Global Identifier (EUI-64) standard. The data returned in the device identification VPD page for this logical unit is shown in
Table 392.
Table 392

Device Identification page example

Bytes

Hexadecimal values

00–15
16–31
32–47
48–53

00 83
53 75
32 30
CD FF

00
70
33
FF

32
65
34
23

02
72
35
45

01
20
38
67

00
54
39

22
75
33

58
72
34

59
62
35

ASCII values
5A
6F
01

5F
20
02

43
44
00

6F
69
08

72
73
01

70
6B
AB

...2...XYZ_Corp [5]
Super Turbo Disk
2034589345.......
......

Notes.
a) Non-printing ASCII characters are shown as “.”.
b) Byte 00 is the beginning of the VPD page (see Table 370).
c) Byte 04 is the beginning of the Identification descriptor for the Vendor ID based identifier (Identifier type 1 see
Table 391).
d) Byte 42 is the beginning of the Identification Descriptor for the EUI-64 identifier (Identifier type 2, see Table 391).
e) For Seagate devices, this will say “Seagate.”
4.4.10

Jumper Settings page (C2h)

This VPD page is obsolete and not supported on newer products.
Table 393
Bit
Byte
0

Jumper Settings page (C2h)
7

6

5

4

3

PERIPHERAL QUALIFIER

PAGE CODE (C2h)

2

00h

3

PAGE LENGTH (02h)
DS

MS

WP

5

1

0

PERIPHERAL DEVICE TYPE

1

4

2

PE
Reserved

DRIVE ID
TE

PERIPHERAL QUALIFIER and PERIPHERAL DEVICE TYPE fields
The PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field are defined in STANDARD INQUIRY DATA (see 3.6.2).
PAGE CODE field
The PAGE CODE field shall be set to the value defined in table .
PAGE LENGTH field
The PAGE LENGTH field specifies the length of the following VPD page data. The relationship between the PAGE LENGTH field and the
CDB ALLOCATION LENGTH field is defined in 2.2.6.

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DS (Delayed Motor Start) bit
The Delayed Motor Start (DS) bit when set to 1 indicates that this jumper is on.
MS (Motor Start) bit
The Motor Start (MS) bit when set to 1 indicates that the jumper is on.
WP (Write Protect) bit
The Write Protect (WP) bit when set to 1 indicates that the write protect jumper is on.
PE (Parity Enable) and PD (Parity Disable) bits
On some drives, Parity Enable (PE) bit when set to 1 indicates that SCSI parity error checking jumper is on. Other drives have a PD (PARITY DISABLE) jumper, where Parity is enabled when the jumper is off. See individual drive’s Product Manual, Volume 1, or Installation
Guide for information on how the drive of interest is set up.
Drive ID field
The Drive ID is shown below in Table 394. Bit 3 is the most significant bit and bit 0 is the least significant bit.
Table 394

Drive ID bit

Bit 3

Bit 2

Bit 1

Bit 0

Drive ID

0

0

0

0

0

0

0

0

1

1

0

0

1

0

2

0

0

1

1

3

0

1

0

0

4

0

1

0

1

5

0

1

1

0

6

0

1

1

1

7

1

0

0

0

8

1

0

0

1

9

1

0

1

0

10

1

0

1

1

11

1

1

0

0

12

1

1

0

1

13

1

1

1

0

14

1

1

1

1

15

TE (Terminator Enable) bit
Terminator Enable (TE) is not used on all drives. See individual drive’s Product Manual, Volume 1, for applicability.
Note.

It is not presently possible to return information on the Terminator Power (TP) jumpers.

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4.4.11

Logical Block Provisioning VPD page

The Logical Block Provisioning VPD page (see table 395) provides the application client with logical block provisioning related operating
parameters of the logical unit.
Table 395
Bit
Byte
0
1
2
3
4
5
6
7
8
...
63

Logical Block Provisioning VPD page
7

6

5

PERIPHERAL QUALIFIER
(MSB)

LBPU

4

3

2

1

PERIPHERAL DEVICE TYPE
PAGE CODE (B2h)
PAGE LENGTH (n - 3)

LBPWS

LBPWS10
Reserved

0

THRESHOLD EXPONENT
Reserved

(LSB)
LBPRZ
ANC_SUP
DP
PROVISIONING TYPE

Reserved
PROVISIONING GROUP DESCRIPTOR (if any)

PERIPHERAL QUALIFIER and PERIPHERAL DEVICE TYPE fields
The PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field are defined in SPC-4.
PAGE CODE field
The PAGE CODE field is defined in SPC-4 and shall be set to the value shown in table 395 for the Logical Block Provisioning VPD page.
PAGE LENGTH field
The PAGE LENGTH field is defined in SPC-4. If the DP bit is set to zero, then the PAGE LENGTH field shall be set to 0004h. If the DP bit
is set to one, then the PAGE LENGTH field shall be set to the value defined in table 395.
THRESHOLD EXPONENT field
The THRESHOLD EXPONENT field set to a non-zero value indicates the threshold set size in LBAs as a power of 2 (i.e., the threshold set
size is equal to 2(threshold exponent)). A THRESHOLD EXPONENT field set to zero indicates that the logical unit does not support logical
block provisioning thresholds.
If logical block provisioning thresholds are supported, then the threshold exponent shall be a non-zero value selected such that:
(capacity ÷ 2(threshold exponent)) < 2(32)
where:
capacity

is 1 + the LBA of the last logical block as returned in the READ CAPACITY (16) parameter data (see 3.24.2)
(i.e., the number of logical blocks on the direct access block device);

and
2(32)

is the constant value 1_0000_0000h (i.e., 4 294 967 296).

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LBPU bit
1

A logical block provisioning unmap (LBPU) bit set to one indicates that the device server supports the UNMAP command (see
3.54).

0

An LBPU bit set to zero indicates that the device server does not support the UNMAP command.

LBPWS bit
1

A logical block provisioning write same (LBPWS) bit set to one indicates that the device server supports the use of the WRITE
SAME (16) command (see 3.72) to unmap LBAs.

0

An LBPWS bit set to zero indicates that the device server does not support the use of the WRITE SAME (16) command to unmap
LBAs.

LBPWS10 bit
1

A logical block provisioning write same 10 (LBPWS10) bit set to one indicates that the device server supports the use of the WRITE
SAME (10) command (see 3.71) to unmap LBAs.

0

An LBPWS10 bit set to zero indicates that the device server does not support the use of the WRITE SAME (10) command to
unmap LBAs.

LBPRZ bit
The logical block provisioning read zeros (LBPRZ) bit shall be set to the same value as the LBPRZ bit in the READ CAPACITY (16) parameter data (see 3.24).
ANC_SUP bit
1

An anchor supported (ANC_SUP) bit set to one indicates that the device server supports anchored LBAs (see SBC-3).

0

An ANC_SUP bit set to zero indicates that the device server does not support anchored LBAs.

DP bit
1

A descriptor present (DP) bit set to one indicates a PROVISIONING GROUP DESCRIPTOR field is present.

0

A DP bit set to zero indicates a PROVISIONING GROUP DESCRIPTOR field is not present.

PROVISIONING TYPE field
The PROVISIONING TYPE field is defined in table 396..
Table 396

Provisioning Type field

Code

Description

000b

The device server does not report a provisioning type.

001b

The logical unit is resource provisioned (see SBC-3).

010b

The logical unit is thin provisioned (see SBC-3).

All others

Reserved

PROVISIONING GROUP DESCRIPTOR field
The PROVISIONING GROUP DESCRIPTOR field, if any, contains a designation descriptor (see SPC-4) for the LBA mapping resources
used by this logical unit.
If a PROVISIONING GROUP DESCRIPTOR field is present:
a) the ASSOCIATION field shall be set to 00b (i.e. logical unit); and
b) the DESIGNATOR TYPE field shall be set to:
A) 1h (i.e., T10 vendor ID based); or
B) 3h (i.e., NAA).

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4.4.12

Mode Page Policy VPD page (87h)

The Mode Page Policy VPD page (see table 397) indicates which mode page policy (see table 3.9) is in effect for each mode page
supported by the logical unit.
Table 397
Bit
Byte
0
1
2
3

Mode Page Policy VPD page
7

6

5

PERIPHERAL QUALIFIER

4

3

2

1

0

PERIPHERAL DEVICE TYPE
PAGE CODE (87h)

(MSB)

PAGE LENGTH (n-3)

(LSB)

Mode page policy descriptor list
4
...
7
...
n-3
...
n

Mode page policy descriptor [first] (see table 398)
...
Mode page policy descriptor [last] (see table 398)

PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field
The PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field are defined in STANDARD INQUIRY DATA (see 3.6.2).
PAGE CODE field
The PAGE CODE field is defined in SPC-4 and shall be set to the value defined in table 397.
PAGE LENGTH field
The PAGE LENGTH field indicates the length of the mode page policy descriptor list. The relationship between the PAGE LENGTH field
and the CDB ALLOCATION LENGTH field is defined in 2.2.6.
Each mode page policy descriptor (see table 398) contains information describing the mode page policy for one or more mode pages or
subpages (see 4.3.5). The information in the mode page policy descriptors in this VPD page shall describe the mode page policy for every
mode page and subpage supported by the logical unit.
Table 398
Bit
Byte
0
1
2
3

Mode page policy descriptor
7

6
Reserved

MLUS

SCSI Commands Reference Manual, Rev. H

5

4

3

2

POLICY PAGE CODE
POLICY SUBPAGE CODE
Reserved
Reserved

1

0

MODE PAGE POLICY

355

POLICY PAGE CODE field and POLICY SUBPAGE CODE field
The POLICY PAGE CODE field and POLICY SUBPAGE CODE field indicate the mode page and subpage to which the descriptor applies.
If the first mode page policy descriptor in the list contains a POLICY PAGE CODE field set to 3Fh and a POLICY SUBPAGE CODE field set
to FFh, then the descriptor applies to all mode pages and subpages not described by other mode page policy descriptors. The POLICY
PAGE CODE field shall be set to 3Fh and the POLICY SUBPAGE CODE field shall be set to FFh only in the first mode page policy descriptor in the list.
If the POLICY PAGE CODE field contains a value other than 3Fh and a POLICY SUBPAGE CODE field contains a value other than FFh,
then the POLICY PAGE CODE field and the POLICY SUBPAGE CODE field indicate a single mode page and subpage to which the
descriptor applies.
If the POLICY PAGE CODE field contains a value other than 3Fh, then POLICY SUBPAGE CODE field shall contain a value other than
FFh. If the POLICY SUBPAGE CODE field contains a value other than FFh, then POLICY PAGE CODE field shall contain a value other
than 3Fh.
MLUS bit
If the SCSI target device has more than one logical unit:
1

A multiple logical units share (MLUS) bit set to one indicates the mode page and subpage identified by the POLICY PAGE CODE
field and POLICY SUBPAGE CODE field is shared by more than one logical unit.

0

A MLUS bit set to zero indicates the logical unit maintains its own copy

The MLUS bit is set to one in the mode page policy descriptors or descriptor that indicates the mode page policy for the:
a) Disconnect-Reconnect mode page (see 4.3.11); and
d) Protocol Specific Port mode page (see 4.3.18).
MODE PAGE POLICY field
The MODE PAGE POLICY field (see table 399) indicates the mode page policy for the mode page and subpage identified by the POLICY
PAGE CODE field and POLICY SUBPAGE CODE field. The mode page policies are described in table 64 (see 3.9).
Table 399
Code

MODE PAGE POLICY field
Description

00b

Shared

01b

Per target port

10b

Obsolete

11b

Per I_T nexus

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4.4.13

Power Conditions Vital Product Data page (8Ah)

The Power Condition VPD page (see table 400) indicates which power conditions (see SPC-4) are supported by the logical unit and
provides information about how those power conditions operate.
Table 400
Bit
Byte
0

Power Condition VPD page
7

6

5

4

PERIPHERAL QUALIFIER
(MSB)

PAGE LENGTH (000Eh)

Reserved
(MSB)
(MSB)

9
(MSB)

11
12

STANDBY_Z

IDLE_B

IDLE_A

STANDBY_Y CONDITION RECOVERY TIME

(MSB)
(MSB)

15
16

STANDBY_Y

STANDBY_Z CONDITION RECOVERY TIME

13
14

IDLE_C

STOPPED CONDITION RECOVERY TIME

7

10

0

(LSB)

Reserved

4
5

8

1

PERIPHERAL DEVICE TYPE

3

6

2

PAGE CODE (8Ah)

1
2

3

(MSB)

17

IDLE_A CONDITION RECOVERY TIME
IDLE_B CONDITION RECOVERY TIME
IDLE_C CONDITION RECOVERY TIME

(LSB)
(LSB)
(LSB)
(LSB)
(LSB)
(LSB)

PERIPHERAL QUALIFIER field and PERIPHERAL DEVICE TYPE field
The PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field are defined in STANDARD INQUIRY DATA (see 3.6.2).
PAGE CODE field and PAGE LENGTH field
These fields are defined in STANDARD INQUIRY DATA (see 3.6.2), and shall be set to the value shown in table 400 for the Power Condition VPD page.
If set to one, a power condition support bit (i.e., the STANDBY_Y bit, the STANDBY_Z bit, the IDLE_C bit, the IDLE_B bit, and the IDLE_A
bit) indicates that:
a. the associated power condition may be entered with the START STOP UNIT command (see SBC-3) if that command is
implemented; and
b. the associated power condition may be entered with a power condition timer if the associated timer is supported and enabled
(see 4.3.14).
STANDBY_Y power conditions support bit
1

This bit set to one indicates that the logical unit supports the standby_y power condition as described in this subclause.

0

This bit set to zero indicates that the logical unit does not support the standby_y power condition.

STANDBY_Z power conditions support bit
1

This bit set to one indicates that the logical unit supports the standby_z power condition as described in this subclause.

0

This bit set to zero indicates that the logical unit does not support the standby_z power condition.

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IDLE_C power conditions support bit
1

This bit set to one indicates that the logical unit supports the idle_c power condition as described in this subclause.

0

A IDLE_C bit set to zero indicates that the logical unit does not support the idle_c power condition.

IDLE_B power conditions support bit
1

This bit set to one indicates that the logical unit supports the idle_b power condition as described in this subclause.

0

A IDLE_B bit set to zero indicates that the logical unit does not support the idle_b power condition.

IDLE_A power conditions support bit
1

This bit set to one indicates that the logical unit supports the idle_a power condition as described in this subclause.

0

A IDLE_A bit set to zero indicates that the logical unit does not support the idle_a power condition.

STOPPED CONDITION RECOVERY TIME field
This field indicates the time, in one millisecond increments, that the logical unit takes to transition from the stopped power condition to the
active power condition. This field is only applicable to SCSI target devices that implement the START STOP UNIT command (see SBC-3).
This time does not include the processing time for the command that caused this transition to occur or any SCSI transport protocol specific
waiting time (e.g., the NOTIFY (ENABLE SPINUP) requirement described in SPL). A value of zero indicates that the recovery time is not
specified. A value of FFFFh indicates that the recovery time is more than 65.534 seconds.
STANDBY_Z CONDITION RECOVERY TIME field
This field indicates the time, in one millisecond increments, that the logical unit takes to transition from the standby_z power condition to
the active power condition. This time does not include the processing time for the command that caused this transition to occur or any
SCSI transport protocol specific waiting time (e.g., the NOTIFY (ENABLE SPINUP) requirement described in SPL). A value of zero indicates that the recovery time is not specified. A value of FFFFh indicates that the recovery time is more than 65.534 seconds.
STANDBY_Y CONDITION RECOVERY TIME field
This field indicates the time, in one millisecond increments, that the logical unit takes to transition from the standby_y power condition to
the active power condition. This time does not include the processing time for the command that caused this transition to occur or any
SCSI transport protocol specific waiting time (e.g., the NOTIFY (ENABLE SPINUP) requirement described in SPL). A value of zero indicates that the recovery time is not specified. A value of FFFFh indicates that the recovery time is more than 65.534 seconds.
IDLE_A CONDITION RECOVERY TIME field
This field indicates the time, in one millisecond increments, that the logical unit takes to transition from the idle_a power condition to the
active power condition. This time does not include the processing time for the command that caused this transition to occur. A value of zero
indicates that the recovery time is not specified. A value of FFFFh indicates that the recovery time is more than 65.534 seconds.
IDLE_B CONDITION RECOVERY TIME field
This field indicates the time, in one millisecond increments, that the logical unit takes to transition from the idle_b power condition to the
active power condition. This time does not include the processing time for the command that caused this transition to occur. A value of zero
indicates that the recovery time is not specified. A value of FFFFh indicates that the recovery time is more than 65.534 seconds.
IDLE_C CONDITION RECOVERY TIME field
This field indicates the time, in one millisecond increments, that the logical unit takes to transition from the idle_c power condition to the
active power condition. This time does not include the processing time for the command that caused this transition to occur. A value of zero
indicates that the recovery time is not specified. A value of FFFFh indicates that the recovery time is more than 65.534 seconds.

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4.4.14

Power Consumption Vital Product Data page

The Power Consumption VPD page (see table 401) provides an application client with a list of the available settings to limit the maximum
power consumption (e.g., see USB-3) of the logical unit while in the active power condition (see SPC-4)..
Table 401
Bit
Byte
0
1
2
3

Power Consumption VPD page
7

6

5

4

PERIPHERAL QUALIFIER

3

2

1

0

PERIPHERAL DEVICE TYPE
PAGE CODE (8Dh)

(MSB)

PAGE LENGTH (n-3)

(LSB)

Power consumption descriptor list
4
...
7
...
n-3
...
n

Power consumption descriptor [first]
...
Power consumption descriptor [last]

PERIPHERAL QUALIFIER and PERIPHERAL DEVICE TYPE fields
The PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field are defined in STANDARD INQUIRY DATA (see 3.6.2).
PAGE CODE and PAGE LENGTH fields
The PAGE CODE field and PAGE LENGTH field are defined in STANDARD INQUIRY DATA (see 3.6.2), and shall be set to the value
shown in table 401 for the Power Consumption VPD page.
Each power consumption descriptor (see table 402) describes one maximum power consumption level that the application client may
establish for use by the active power condition (see SPC-4) using the Power Consumption mode page (see 4.3.14) as described in SPC-4.
Table 402
Bit
Byte
0
1
2
3

Power consumption descriptor format
7

6

5

4

3

2

1

0

POWER CONSUMPTION INDENTIFIER
Reserved
POWER CONSUMPTION UNITS
(MSB)

POWER CONSUMPTION VALUE

(LSB)

POWER CONSUMPTION IDENTIFIER field
The POWER CONSUMPTION IDENTIFIER field provides a reference handle to specify which descriptor is selected by the Power Consumption mode page as described in SPC-4.
POWER CONSUMPTION UNITS field
The POWER CONSUMPTION UNITS field (see table 402) indicates the units used for the POWER CONSUMPTION VALUE field.
Table 403

POWER CONSUMPTION UNITS field

Code

Description

000b

Gigawatts

001b

Megawatts

010b

Kilowatts

011b

Watts

100b

Milliwatts

101b

Microwatts

all others

Reserved

POWER CONSUMPTION VALUE field
The POWER CONSUMPTION VALUE field indicates the maximum power consumption associated with the identifier in the POWER CONSUMPTION IDENTIFIER field using the units specified by the POWER CONSUMPTION UNITS field.
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4.4.15

SCSI Ports VPD page

The SCSI Ports VPD page (see table 636) contains designation descriptors for all the SCSI ports in a SCSI target device.
The SCSI Ports VPD page only reports information on SCSI ports known to the device server processing the INQUIRY command. The
REPORT LUNS well-known logical unit (see 3.34) may be used to return information on all SCSI ports in the SCSI device (i.e., all target
ports and all initiator ports).
If the device server detects that a SCSI port is added or removed from the SCSI device and the SCSI port designation descriptor list
changes, then the device server shall establish a unit attention condition (see SAM-5) for the initiator port associated with every I_T nexus,
with the additional sense code set to INQUIRY DATA HAS CHANGED.
Table 404
Bit
Byte
0
1
2
3

SCSI Ports VPD page
7

6

5

PERIPHERAL QUALIFIER
(MSB)

4

3

2

1

0

PERIPHERAL DEVICE TYPE
PAGE CODE (88h)
PAGE LENGTH (n-3)

(LSB)

Designation descriptor list
4
...

SCSI port designation descriptor [first] (see table 405)
...

...
n

SCSI port designation descriptor [last] (see table 405)

PERIPHERAL QUALIFIER, PERIPHERAL DEVICE TYPE, and PAGE LENGTH fields
The PERIPHERAL QUALIFIER field, PERIPHERAL DEVICE TYPE field, and PAGE LENGTH field are defined in STANDARD INQUIRY
DATA (see 3.6.2).
PAGE CODE fields
The PAGE CODE field is defined in STANDARD INQUIRY DATA (see 3.6.2), and shall be set to the value shown in table 404 for the SCSI
Ports VPD page.

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Each SCSI port designation descriptor (see table 405) identifies a SCSI port. The SCSI port designation descriptors may be returned in
any order..
Table 405

SCSI port designation descriptor

Bit
Byte

7

6

5

4

0

3

2

1

0

Reserved

1
(MSB)

2

RELATIVE PORT IDENTIFIER (see table 406)

3
4

(LSB)

Reserved

5
(MSB)

6

INITIATOR PORT TRANSPORTID LENGTH (k-7)

7

(LSB)

8
INITIATOR PORT TRANSPORTID (if any)

...
k
k+1

Reserved

k+2
(MSB)

k+3

TARGET PORT DESCRIPTORS LENGTH (n-(k+4))

k+4

(LSB)

Target port descriptor list
k+5
Target port descriptor [first] (see table 407)

...

...

Target port descriptor [last] (see table 407)

...
n
RELATIVE PORT IDENTIFIER field

The RELATIVE PORT IDENTIFIER field (table 406) contains the relative port identifier of the SCSI port to which the SCSI port designation
descriptor applies.
Table 406

Relative Port Identifier field

Code

Description

0h

Reserved

1h

Relative port 1, historically known as port A

2h

Relative port 1, historically known as port B

3h to FFFFh

Relative port 3 through 65 535

INITIATOR PORT TRANSPORTID LENGTH field
The INITIATOR PORT TRANSPORTID LENGTH field indicates the length of the INITIATOR PORT TRANSPORTID field.
zero value
non-zero value

indicates no INITIATOR PORT TRANSPORTID field is present (i.e., the SCSI port is not an initiator port).
indicates a TransportID identifying the initiator port as defined in SPC-4.

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TARGET PORT DESCRIPTORS LENGTH field
The TARGET PORT DESCRIPTORS LENGTH field indicates the length of the target port descriptors, if any. A TARGET PORT
DESCRIPTORS LENGTH field set to zero indicates no target port descriptors are present (i.e., the SCSI port is not a target port).
Each target port descriptor (see table 407) contains an identifier for the target port. The target port descriptors may be returned in any
order.
Table 407
Bit
Byte

Target port Descriptor
7

5

4

3

PROTOCOL IDENTIFIER

0
1

6

PIV (1b)

Reserved

2

1

0

CODE SET

ASSOCIATION (01b)

2

Reserved

3

DESIGNATOR LENGTH (n – 3)

DESIGNATOR TYPE

4
...

DESIGNATOR

n
PROTOCOL IDENTIFIER field
The PROTOCOL IDENTIFIER field indicates the SCSI transport protocol to which the designation descriptor applies as described in table
325.
CODE SET field, PIV field, ASSOCIATION field, DESIGNATOR TYPE field, DESIGNATOR LENGTH field, and DESIGNATOR field
The CODE SET field, PIV field, ASSOCIATION field, DESIGNATOR TYPE field, DESIGNATOR LENGTH field, and DESIGNATOR field
are as defined in the Device Identification VPD page designation descriptor (see SPC-4), with the following additional requirements:
a) the PIV bit shall be set to one (i.e., the PROTOCOL IDENTIFIER field always contains a SCSI transport protocol identifier); and
b) the ASSOCIATION field shall be set to 01b (i.e., the descriptor always identifies a target port).

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4.4.16

Supported Vital Product Data pages (00h)

This clause contains a list of the vital product data page codes supported by the target or logical unit (see table 408). If a target supports
any vital product data pages, it also shall support this vital product data page.
Table 408
Bit
Byte
0

Supported Vital Product Data pages
7

6

5

4

3

PERIPHERAL QUALIFIER

1

2

1

0

PERIPHERAL DEVICE TYPE
PAGE CODE (00h)

2

Reserved

3

PAGE LENGTH (n-3)

4
...

SUPPORTED PAGE LIST

n
PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field
The PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field are defined in STANDARD INQUIRY DATA (see 3.6.2).
PAGE CODE field
The PAGE CODE field is defined in SPC-4 and shall be set to the value defined in table 408.
PAGE LENGTH field
The PAGE LENGTH field indicates the length of the mode page policy descriptor list. The relationship between the PAGE LENGTH field
and the CDB ALLOCATION LENGTH field is defined in 2.2.6.
SUPPORTED PAGE LIST field
The SUPPORTED PAGE LIST field shall contain a list of all vital product data page codes (see clause 4.4.1) implemented for the target or
logical unit in ascending order beginning with page code 00h.

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4.4.17

Unit Serial Number page (80h)

This page provides a product serial number for the target or logical unit. See Table 409 following.
Table 409
Bit
Byte
0

Unit Serial Number page (80h)
7

6

5

4

3

PERIPHERAL QUALIFIER

2

1

0

PERIPHERAL DEVICE TYPE

1

PAGE CODE (80h)

2

Reserved

3

PAGE LENGTH

4
...

Product Serial Number

n
PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field
The PERIPHERAL QUALIFIER field and the PERIPHERAL DEVICE TYPE field are defined in STANDARD INQUIRY DATA (see 3.6.2).
PAGE CODE field
The PAGE CODE field shall be set to the value defined in table 409.
PAGE LENGTH field
The PAGE LENGTH field specifies the length in bytes of the product serial number page. Older products that only support the Product
Serial Number parameter will have a page length of 08h, while newer products that support both parameters will have a page length of
14h. If the ALLOCATION LENGTH is too small to transfer all of the page, the page length shall not be adjusted to reflect the truncation.
Product Serial Number field
The Product Serial Number field contains ASCII data that is vendor-assigned serial number. The least significant ASCII character of the
serial number shall appear as the last byte in the Data-In Buffer. If the product serial number is not available, the target shall return ASCII
spaces (20h) in this field.

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INDEX
Numerics

B

10 byte commands 37
12 byte commands 37
16 byte commands 37
32 byte commands 37
6 byte commands 37

Background Control mode
Page description 259
Background medium scan features 223
Background Scan Results log page 222
BLOCK DESCRIPTOR 252
Block Device Characteristics VDP page (B1h) 335
BLOCK LENGTH IN BYTES 105
BLOCK LENGTH IN BYTES field 105
BUFFER CAPACITY
BUFFER CAPACITY field 98
Read Buffer Header 98
BUFFER EMPTY RATIO
Disconnect-Reconnect Mode page 270
BUFFER FULL RATIO
Disconnect-Reconnect mode page 270
BUFFER ID
Read Buffer Command 97
Write Buffer Command 189
BUFFER OFFSET
Read Buffer Command 97
BUS INACTIVITY LIMIT 270
BUS INACTIVITY LIMIT field 271

A
Abbreviations 9
ABPF. See Abort Prefetch
ADDITIONAL CDB LENGTH 14
ADDITIONAL CDB LENGTH field 14
ADDITIONAL LENGTH 55, 74
ADDITIONAL LENGTH field 58
Diagnostic Data Bytes 118
Standard Inquiry Data 55
Additional Length
Diagnostic Data Bytes 118
Additional sense 2
additional sense
qualifier code 31
Additional Sense code 2
additional sense code 31
ADDR16 (wide SCSI address 16) bit 61
Address Field Logical Block Address Format 206
Address Field Physical Sector Address Format 207
ALLOCATION LENGTH
CDB 10-byte 13
CDB 12-byte 13
CDB 6-byte 12
CDB for long LBA 16-byte 13
CDB for long LBA 32-byte 15
Definition 17
Receive Diagnostic Results command 117
Allocation Length
Inquiry command 54
Log Sense command 67
Mode Sense command 70
Persistent Reserve In command 73
Read Buffer command 97
Read Capacity command 106
Read Defect Data command 109
Report Device Identifier command 121
Report LUNS command 123, 132
Request Sense command 136
Allocation length 17
ALLOCATION LENGTH field
Receive Diagnostic Results command 117
Allow Login Without Loop Initialization
Fibre Channel Interface Control page 302, 304
ALWLI. See Allow Login Without Loop Initialization
Application Client log page 221
ARRE bit 286
ASCII Information 334
ASCII Information VPD page (01h - 7Fh) 334
AWRE bit 286
SCSI Commands Reference Manual, Rev. H

C
Cache Statistics 226
Cache statistics page 226
CHANGE DEFINITION command 39
Change Definition command 38
check condition status 18
Code set field 349
Command
6, 10, 12, 16, 32 bytes 37
alphabetical listing 37
for all devices 37
for direct access devices 37
Command Descriptor Block (CDB) 12
Command length 37
Command type
All devices 37
Direct access devices 37
COMPARE command 40
Compare command 40
Compile Date Code
ETF Log Date Code page 340
CONNECT TIME LIMIT 270
CONNECT TIME LIMIT field 271
Control mode page (0Ah) 264
Conventions 11
COPY AND VERIFY command 40
Copy and Verify command 40
COPY command 40
Copy command 40

365

INDEX
DTDC
Data Transfer Disconnect Control field 270
DTDC (Data Transfer Disconnect Control) field 272
DTFD. See Disable Target Fabric Discovery
DTIPE. See Disable Target Initiated Port Enable
DTOLI. See Disable Target Oriented Loop Initialization

D
Date Code page 340
DDIS. See Disable Discovery
Definitions 2
Device type field 237, 238
Diagnostic Data Bytes
Receive Diagnostic Results command 118
Diagnostic data list 118
Diagnostic Fault Codes
Vendor Unique 118
Diagnostic operation 118
Diagnostic page format 203
Diagnostic Parameters
Background Scan Results log page 222
Cache Statistics page 226
Log page codes 212
PAGE CODE field identifies 204
Supported Diagnostic Pages 205
Supported Log Pages log page 247
Temperature log page 249
Diagnostic parameters 203
DIMM
DIMM (disconnect immediate) bit 272
DIMM. Disconnect Immediate 270
Disable Discovery
Fibre Channel Interface Control page 302,
Disable Loop Master
Fibre Channel Interface Control page 302,
Disable Page Out bit 93, 263
Disable Prefetch Transfer Length
Caching Parameters page 262
Disable Soft Address
Fibre Channel Interface Control page 302,
Disable Target Fabric Discovery
Fibre Channel Interface Control page 302
Disable Target Initiated Port Enable
Fibre Channel Interface Control page 302,
Disable Target Oriented Loop Initialization
Fibre Channel Interface Control page 302,
Disabled Physical Element
Translate Address page 210, 211
Disabled Physical Element Mask
Translate Address page 210, 211
DISCONNECT TIME LIMIT 270
DISCONNECT TIME LIMIT field 271
Disconnect-Reconnect mode page (02h) 270
DLM. See Disable Loop Master
DPO
See Disable Page Out bit 91, 93, 263
Driver Asymmetry
Margin control subpage 298
Driver Slew Rate
Margin control subpage 298
DSA. See Disable Soft Address
SCSI Commands Reference Manual, Rev. H

E
EN_BMS
Enable Background Medium Scan 259
Enable Vital Product Data bit 54
Error Code
Diagnostic Data Bytes 118
Error code
definition 117
ETF Log Date Code page 340
ETF Log field 340
EVPD. See Enable Vital Product Data bit
Extended bytes from index address descriptor 50
Extended INQUIRY Data VPD page (86h) 342
Extended physical sector address descriptor 51
extended sense
codes 31

F
303, 304
303

303

304
304

Factory Log page 229
Factory log page 229
FAIR ARBITRATION 270
FAIR ARBITRATION field 272
Fibre Channel Logical Unit Control mode page 292
field
maximum-value 18
minimum-value 18
Field Replaceable Unit
Diagnostic Data Bytes 118
Field replaceable unit 117
Fixed length CDBs 12
CDB for 10-byte commands 13
CDB for 12-byte commands 13
CDB for 6-byte commands 12
CDB for long LBA 16-byte commands 13
Force unit access bit 94
Format parameters
page 277
FORMAT UNIT command 40
FORMAT UNIT parameter list 43
FRU. see Field Replaceable Unit
FUA
See Force unit access bit 91

G
GROUP NUMBER field 94, 162
Grouping function 18

366

INDEX
I
Identification Descriptor 349
illegal request sense key 18
Information
Response codes 70h and 71h sense data format 28
Informational Exceptions Control mode page (1Ch) 279
INQUIRY command 54

J
Jumper settings page 351

K

MODE SENSE(10) command 72
MODE SENSE(6) command 70
PAGE CODE and SUBPAGE CODE fields 71

N
NEGOTIATED LOGICAL LINK RATE field 238
Negotiated settings subpage 296, 300
Non-Medium Error log page (06h) 232
NUMBER OF CYLINDERS 328
NUMBER OF CYLINDERS field 329

O

Log parameters 212
LOG SELECT command 63
LOG SENSE command 67
Logical block address 16
LOGICAL BLOCK ADDRESS field 94, 162
LOGICAL BLOCK LENGTH
Mode Parameter Block Descriptor 255
LUN LIST LENGTH field 125

OPERATION CODE
CDB 10-byte 13
CDB 12-byte 13
CDB 16-byte Long LBA 13
CDB 32-byte Long LBA 15
CDB 6-byte 12
Defined 5
Description 16
Values sorted by Command Name 37
Variable length CDB 14
OVERWRITE 142
OVERWRITE service action 142

M

P

Margin control subpage 296, 297
MAXIMUM BURST SIZE 270
MAXIMUM BURST SIZE field 271
maximum-value field 18
Medium Scan Parameter 224
minimum-value field 18
Mode page policy 68
Mode parameter block descriptor formats 253
Mode parameter header 252
Mode parameters 251
Caching Parameters page 261
Control Extension mode page 269
Control mode page 264
Disconnect-Reconnect mode page 270
Disconnect-Reconnect mode page for FCP 273
Disconnect-Reconnect mode page for SAS 275
General block descriptor format 253
MODE DATA LENGTH field 252
Mode parameter header 252
Mode parameter header formats 252
Mode parameter list format 252
Page_0 Mode page format 256
Power Condition mode page 282
Protocol Specific Logical Unit mode page 290
Sub_page mode page format 256
Verify Error Recovery mode page 332
Mode Select command 18
MODE SELECT(10) command 70
MODE SELECT(6) command 68

PAGE CODE 117
Page Code
ASCII Implemented Operating Definition page 341
Caching Parameters page 261
Fibre Channel Interface Control page 302
Port Control Mode page 295
Rigid Drive Geometry Parameters page 328
Translate Address page 209, 210, 211
PAGE CODE and SUBPAGE CODE fields. See Mode Sense
(6) command
Page Length
ETF Log Date Code page 340
Fibre Channel Interface Control page 302
Port Control Mode page 295
Power Condition page 302
Translate Address page 209, 210, 211
Parameter List Length 17
PARAMETER LIST LENGTH field 64
Parameter Savable
Port Control Mode page 295, 296
Power Condition page 302
parameter value
rounding 18
PC. See Page Control field 63
PCR
See Parameter Code Reset 63
Percentage Used Endurance Indicator log parameter 244
PERIPHERAL DEVICE TYPE 55
Peripheral Device Type

Keywords 10

L

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INDEX
ETF Log Date Code page 340
PERIPHERAL QUALIFIER 55
Peripheral Qualifier Description 56
Peripheral Qualifier
ETF Log Date Code page 340
Persistent reservations type 77
PERSISTENT RESERVE IN command 73
Persistent Reserve In command 74
PERSISTENT RESERVE OUT command 83
PERSISTENT RESERVE OUT parameter list 85
PERSISTENT RESERVE OUT service actions 83
Phy event descriptor 240
Physical Element Length
Translate Address page 210, 211
PLPB. See Prevent Loop Port Bypass
Port Control Mode page (19h) for Fibre Channel 302
Port Control Mode page for Parallel SCSI 295
Power Condition mode page (1Ah) 282
Power Condition Transitions log page 234, 235
Power Conditions Vital Product Data page (8Ah) 357
Power Consumption Mode page (1Ah/ 01h) 285
Power Consumption Vital Product Data page 359
Power on time parameter 229
PPC. See Parameter Pointer Control bit 67
Prefetch (10) command 89
PRESISTANT RESERVE IN command
PRGENERATION (Persistent Reservations Generation)
field 74
Prevent Loop Port Bypass
Fibre Channel Interface Control page 302, 303
Protocol Identifier
Port Control Mode page 295
Protocol Specific Logical Unit mode page (18h) 290
Protocol Specific Port mode page 294
Protocol Specific Port mode page (19h) 294
Protocol-Specific mode page for SAS 305
Protocol-specific Port log parameter for SAS 235

R
RDPROTECT field 91
READ BUFFER command 97
READ CAPACITY command
READ CAPACITY (10) command 104
READ CAPACITY (16) command 106
READ Command
READ (10) command 91
READ (12) command 95
READ (16) command 95
READ (32)command 96
READ (6) command 89
READ DEFECT DATA command
READ DEFECT DATA (10) command 109
READ DEFECT DATA (12) command 111
READ FULL STATUS 81
READ LONG command
READ LONG (10) command 113
SCSI Commands Reference Manual, Rev. H

READ LONG (16) command 114
READ RESERVATION 74
READ RETRY COUNT
Read-Write Error Recovery Mode page 286
READ RETRY COUNT field 289
Read-Write Error Recovery mode page 286
REASSIGN BLOCKS command 115
Rebuild Assist Input diagnostic page 210
Rebuild Assist Output diagnostic page 211
RECEIVE DIAGNOSTIC RESULTS command 117, 203
recovered error sense key 18
RELEASE command
RELEASE(10) command 119
RELEASE(6) command 119
REPORT CAPABILITIES 78
REPORT LUNS command 123
Report transfer capabilities subpage 296
REQUEST SENSE command 136
RESERVE(10) command 138
RESERVE(6) command 137
Retry algorithm 227
Rezero Unit command 140
Rigid drive geometry parameters
page 328
Rigid Drive Geometry Parameters page 328
Rotational Position Locking
Rigid Drive Geometry Parameters page 329
rounded parameter 18
rounding of parameter values 18

S
S.M.A.R.T. see Self-Monitoring Analysis and Reporting
Technology
SANITIZE command 141
SANITIZE service actions 142
SAS Protocol-Specific Logical Unit mode page 293
Save Parameters bit 63
Saved training configuration values subpage 296, 299
SCSI Enclosure Services pages 209
SCSI Parallel Interface specific INQUIRY data 61
SCSI Ports VPD page 360
Seek command 153
Seek Extended command 154
Self-monitoring analysis and reporting technology
measurement 229
SELF-TEST CODE field 242
Self-Test Results log page (10h) 241
SEND DIAGNOSTIC command 155, 203
Send Diagnostic command 117
Sense data 19
SERVICE ACTION field 14, 16
Solid State Media log page 243, 257
Solid State Media log parameters 243, 245
Stable error correction code syndrome 227
Standard INQUIRY data 55
Standard INQUIRY data format 55
368

INDEX
Start-Stop Cycle Counter log page (0Eh) 245
Supported page/subpage descriptor 248
Supported Vital Product Data pages 363
Symbols 9
SYNC (synchronous transfer) bit 61
Synchronous Transfer Timeout
Port Control Mode page 295

T
Target port Descriptor 362
Target Port Group Support field 59
Temperature log page 249
Temperature log page (0Dh) 249
Temperature log page parameter codes 249
TPGS. See Target Port Group Support filed 59
Transfer length 17
TRANSFER LENGTH field 94
Translate Address page 206

WRITE BUFFER command 189
WRITE command
WRITE (10) command 180
WRITE (12) command 184
WRITE (16) command 184
WRITE (32) command 185
WRITE (6) command 179
WRITE LONG command
WRITE LONG (10) command 196
WRITE LONG (16) command 198
WRITE RETRY COUNT
Read-Write Error Recovery Mode page 286
WRITE RETRY COUNT field 289

U
Unit Serial Number page 364
Unrecoverable error 227

V
Variable length CDB formats 14
Typical variable length CDB 14
Typical variable length CDB for long LBA 32-byte commands 15
VENDOR IDENTIFICATION field 60
Vendor Unique Fault Information
Diagnostic Data Bytes 118
VERIFY command
VERIFY (10) command 169
VERIFY (12) command 177
VERIFY (16) command 177
VERIFY (32) command 177
Verify Error Recovery mode page 332
VERSION DESCRIPTOR fields 60
VERSION field 58
Vital Product Data 62
Vital Product Data page
ASCII Information VDP page 334
Device Behavior page 341
Device Identification VPD page 348
ETF Log Date Code page 340
Supported Vital Product Data pages 363
Unit Serial Number page 364

W
WBUS16 (wide bus 16) bit 61
WRITE AND VERIFY command
WRITE AND VERIFY (10) command
WRITE AND VERIFY (12) command
WRITE AND VERIFY (16) command
WRITE AND VERIFY (32) command

186
187
187
188

SCSI Commands Reference Manual, Rev. H

369

Seagate Technology LLC
AMERICAS Seagate Technology LLC 10200 South De Anza Boulevard, Cupertino, California 95014, United States, 408-658-1000
ASIA/PACIFIC Seagate Singapore International Headquarters Pte. Ltd. 7000 Ang Mo Kio Avenue 5, Singapore 569877, 65-6485-3888
EUROPE, MIDDLE EAST AND AFRICA Seagate Technology SAS 16-18 rue du Dôme, 92100 Boulogne-Billancourt, France, 33 1-4186 10 00

Publication Number: 100293068, Rev. H
July 2014



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