Radio Shack Hardware Manual SA800 801 Diskette Drive OEM 1977 Shugart Text

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TABLE OF CONTENTS

1.0 Introduction 1

1.1 General Description 1

1.2 Specification Summary 2

1.2.1 Performance Specifications 2

1.2.2 Functional Specifications 2

1.2.3 Physical Specifications 2

1.2.4 Reliability Specifications 3

2.0 Functional Characteristics 5

2.1 General Operation 5

2.2 Read/Write and Control Electronics 5

2.3 Drive Mechanism 5

2.4 Positioning Mechanism 5

2.5 Read/Write Head 5

2.6 Recording Format 6

2.7 Optional Features 6

2.8 Model Differences 6

3.0 Functional Operations 7

3.1 Power Sequencing 7

3.2 Drive Selection 7

3.3 Track Accessing 7

3.3.1 Step Out 7

3.3.2 Step In 7

3.4 Read Operation 7

3.5 Write Operation 9

3.6 Sequence of Events 9

4.0 Electrical Interface 13

4.1 Signal Interface 13

4.1.1 Input Lines 13

4.1.1 Input Line Termination 15

4.1 .1 .2 Drive Select 1-4 15

4.1 .1 .3 Direction Select 15

4. 1.1.

Step 15

4.1 .1 .5 Write Gate 15

4.1.1.6 Write Data 16

4.1.1.7 Head Load (Alternate Input). 16

4.1 .1 .8 In Use (Alternate Input) 16

4.1 .2 Output Lines 16

4.1 .2.1 Track 00 16

4.1.2.2 Index 16

4.1 .2.3 Sector (SA801 only) 17

4.1 .2.4 Ready 17

4.1 .2.5 Read Data 17

4.1 .2.6 Sep Data 17

4.1 .2.7 Sep Clock 17

4.1 .2.8 Write Protect (Optional on SA800) 17

4.1 .2.9 Disk Change (Alternate Output) 18

4.1.3 Alternate I/O Pins 18

4.2 Power Interface 18

4.2.1 AC Power 18

4.2.2 DC Power 19

5.0 Physical Interface 21

5.1 J1/P1 Connector 21

5.2 J5/P5 Connector 22

5.3 J4/P4 Connector 22

6.0 Drive Physical Specifications 23

6.1 Drive Dimensions 23

6.2 Mounting Recommendations 23

6.2.1 Vertical Mounting 23

6.2.3 Upright Mounting 23

6.3 Chassis Slide 25

6.4 Decorative Face Plate 25

7.0 Customer Installable Options 27

7.1 Drive Select -One to Eight Drives 30

7.2 Select Drive Without Loading Head or Enabling Stepper Motor 31

7.3 Select Drive and Enable Stepper Without Loading Head 32

7.4 Load Head Without Selecting Drive or Enabling Stepper 32

7.5 Radial Ready 33

7.6 Radial Index/Sector 34

7.7 Eight, 16, Or 32 Sectors 35

7.8 In Use Alternate Input (Activity LED) 36

7.9 Write Protect Optional Use 36

7.10 Disk Change (Alternate Output) 37

8.0 Operation Procedures 38

8.1 Diskette Loading and Handling 38

8.2 Write Protecting aDiskette 39

9.0 Error Detection and Correction 40

9.1 Write Error 40

9.2 Read Error 40

Appendix A-Models and Features 41

LIST OF ILLUSTRATIONS

Figure 1.SA800/801 Diskette Storage Drive iv

2. SA800/801 Functional Diagram 4

3. Track Access Timing 8

4. Read Initiate Timing 8

5. Read Signal Timing 9

6. Write Initiate Timing 10

7. Write Data Timing 10

8. General Control and Data Timing Requirements 11

9. Interface Connections 14

10. Interface Signal Driver/Receiver 16

1 1

Index Timing 16

12. Sector Timing 17

13. J1 Connector Dimensions 21

14. J5 Connector .22

15. J4 Connector 22

16. Interface Connectors- Physical Location Diagram 22

17. Head Load Actuator Mounting Prerequisites 23

18. SA800/801 Diskette Storage Drive Dimensions 24

19. Slide Mounting Dimensions 25

20. SA800/801 RDimensions 26

Component Locations Standard PCB 28

22. Component Locations LSI PCB ..29

23. Drive Select Circuitry 30

24. Select Drive Without Loading Head Circuit 31

25. Stepper Motor Enable Circuit 32

26. Load Head Without Selecting Drive or Enabling Stepper Circuit 33

27. Radial Ready Circuit 34

28. Radial Index/Sector Circuit 34

29. Sector Timing Relationships 35

30. Sector Divide Circuit 35

31. In Use/Activity LED Circuit 36

32. Write Protect Circuit 36

33. Disk Change Timing 37

34. Disk Change Circuit 37

35. Loading SA800/801 .38

36. Diskette Write Protected 39

37. Write Inhibit Notch Specifications 39

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Figure 1. SA800/801 Diskette Storage Drive

1.0 INTRODUCTION

1.1 General Description

The SA800/801 are enhanced versions of the successful SA900/901 Diskette Storage Drive. The SA800/801

provides the customer with amature and reliable product, manufactured to the same high standard of ex-

cellence as the 900/901, but with additional featuress.

The SA800 Diskette Storage Drive can read and write diskettes for interchange with other SA800's, the

SA900, IBM 3741, 3742 or 3540 and with the IBM System 32.

The SA801 provides the same features as the SA800 with additional flexibility for those requirements which

preclude IBM compatibility.

The SA800/801 Diskette Storage Drives have as standard features: apatented diskette clamping/registra-

tion design which eliminates the possibility of damage to the diskette due to misregistration and quarantees

over 30,000 interchanges with each diskette; single and double density capability on the same drive for the

same price; aproprietary ceramic R/W head designed and manufactured by Shugart Associates to provide

media life exceeding 3.5 million passes/track and head life exceeding 15,000 hours; an activity light which

indicates drive in use; and ribbon cable or twisted pair connector for ease of packaging. All of these features

and more are available with the SA800/801

SA800/801 Diskette Storage Drive provide the system designer solutions to his applications requirements

with greater performance and reliability than cassette or cartridge drives, and lower cost with increased

function over I/O and reel-to-reel tape drives.

Applications for the SA800/801 Diskette Storage Drive are key entry systems, point of sale recording

systems, batch terminal data storage microprogram load and error logging, minicomputer program and aux-

iliary data storage, word processing systems and data storage for small business systems.

The SA100 Diskette, IBM Diskette or equivalent, can be read and written interchangeably between any

SA800and IBM 3741/42, 3747 and 3540. The SA1 01 Diskette can be read or written interchangeably on any

SA801. The SA102 and SA103 are used for double density applications.

As aproduct enhancement, to improve reliability and serviceability, Shugart is incorporating into the SA800

serves drives aPCB Large Scale Integration (LSI) components. These components are:

#Control Chip

•Write Channel

•Read Channel

The LSI Control chip performs the following functions:

@TRK 00 detector

#Index detector

®Stepper logic

®FM clock/data separator and data window

®Sector separator

®Write Protect detector

®Door open/close detector

®Disk change circuit

®Ready signal

The functions listed above are either detected from the drive mechanics or from the Host Interface. As a

result, the proper logic generated by the LSI chip either will be used within the drive electronic circuit to per-

form stepping, read/write operations or will be fed back to the Host Interface.

Also, an internal FM data separator is incorporated inside the chip. Ajumper option will allow the user to

select the data separator to perform as its predecessor SA800 (jumper FS) or to select the separator to be

compatible with the IBM System 3740 data separator (jumper TS). Thus IBM compatibility will allow direct in-

terfacing with LSI single chip floppy disk controllers.

1.2 Specification Summary

1.2.1 Performance Specifications

Capacity

Unformatted

Per Disk

Per Track

IBM Format

Per Disk

Per Track

Tranfer Rate

Latency (average)

Access Time

Track to Track

Average

Settling Time

Head Load Time

1.2.2 Functionai Specifications

Rotational Speed

Recording Density

(inside track)

Flux Density

Track Density

Tracks

Physical Sectors

SA800

SA801

Index

Encoding Method

Media Requirements

SA800

SA801

1.2.3 Physical Specifications

Enviromental Limits

Ambient Temperature

Relative Humidity

Maximum Wet Bulb

AC Power Requirements

50/60 Hz ±0.5 Hz

100/115 VAC Installations

200/230 VAC Installations

DC Voltage Requirements

+24 VDC ±5% 1.3A typical

+5VDC ±5% 0.8A typical

-5 VDC ±5%.05A typical (option -7 to -16 VDC)

Mechanical Dimensions (Reference Figures 18 and 20)

Width =45/8 in. (11.75 cm)

Height =91/2 in. (24.13 cm)

Depth =14 1/4 in. (36.20 cm)

Weight =13.0 lbs. (5.91 kg)

Heat Dissipation =271 BTU/hr. typical (80 Watts)

Single Density Double Density

3.2 megabits

41.7 kilobits

6.4 megabits

83.4 kilobits

2.0 megabits

26.6 kilobits

250 kilobits/sec.

83 ms

n/a

500 kilobits/sec

83 ms

8ms

260 ms

8ms

35 ms

8ms

260 ms

8ms

35 ms

Single Density

360 rpm

Double Density

360 rpm

3200 bpi

6400 fci

48 tpi

6400 bpi

6400 fci

48 tpi

32/16/8 32/16/8

MFM/M2FM

SA100/IBM Diskette

SA101

SA102/IBM Diskette

SA103

Operating

=40°Fto 115°F(4.4°

=20% to 80%

=78°F (25°C)

to46.1°C)

Shipping

-40°F to 144°F

1to 95%

No Condensation

Storage

-8°F to 117°F

1to 95%

No Condensation

=85 to 127V @.

=170 to 253V @3A typical

.18A typical

1.2.4 Reliability Specifications

MTBF:

PM:

MTTR:

Component Life:

Error Rates:

Soft Read Errors:

Hard Read Errors:

Seek Errors:

Media Life:

Passes Per Track

Insertions:

5000 POH under heavy usage

8000 POH under typical usage

Every 5000 POH under heavy usage

Every 15,000 under typical usage

30 minutes

15,000 POH

1per 109bits read

1per 1012 bits read

1per 106seeks.

3.5 x10fc

30,000 +

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Figure 2. SA800/801 Functional Diagram

2.0 FUNCTIONAL CHARACTERISTICS

2.1 General Operation

The SA800/801 Diskette Storage Drive consists of read/write and controls electronics, drive mechanism,

read/write head, track positioning mechanism, and the removable diskette. These components perform the

following functions:

Interpret and generate control signals.

Move read/write head to the selected track.

Read and write data.

The relationship and interface signals for the internal functions of the SA800/801 are shown in Figure 2.

The Head Positioning Actuator positions the read/write head to the desired track on the diskette. The Head

Load Actuator loads the diskette against the read/write head and data may then be recorded or read from

the diskette.

2.2 Read/Write and Control Electronics

The electronics are packaged on one PCB. The PCB contains:

Index Detector Circuits. (Sector/Index for 801).

2. Head Position Actuator Driver.

3. Head Load Actuator Driver.

4. Read/Write Amplifier and Transition Detector.

5. Data/Clock Separation Circuits.

6. Write Protect.

7. Drive Ready Detector Circuit.

8. Drive Select Circuits.

2.3 Drive Mechanism

The Diskette drive motor rotates the spindle at 360 rpm through abelt-drive system. 50 or 60 Hz power is ac-

commodated by changing the drive pulley and belt. Aregistration hub, centered on the face of the spindle,

positions the Diskette. Aclamp that moves in conjunction with the cartridge guide fixes the Diskette to the

registration hub.

2.4 Positioning Mechanism

An electrical stepping motor (Head Position Actuator) and lead screw positions the read/write head. The

stepping motor rotates the lead screw clockwise or counterclockwise in 15° increments. A15° rotation of the

lead screw moves the read/write head one track position. The using system increments the stepping motor

to the desired track.

2.5 Read/Write Head

The SA800/801 head is asingle element ceramic read/write head with straddle erase elements to provide

erased areas between data tracks. Thus normal interchange tolerances between media and drives will not

degrade the signal to noise ratio and insures Diskette interchangeability.

The read/write head is mounted on acarriage which is located on the Head Position Actuator lead screw.

The Diskette is held in aplane perpendicular to the read/write head by aplaten located on the base casting.

This precise registration assures perfect compliance with the read/write head. The Diskette is loaded

against the head with aload pad actuated by the head load solenoid.

The read/write head is in direct contact with the Diskette. The head surface has been designed to obtain

maximum signal transfer to and from the magnetic surface of the Diskette with minimum head/Diskette

wear.

2.6 Recording Format

The format of fhe data recorded on the disk is totally afunction of the host system, and can be designed

around the users application to best take advantage of the total available bits that can be written on any one

track.

For adetailed discussion of various recording formats, the systems designer should read one of the follow-

ing:

1. IBM Compatibility Manual.

2. Shugart Associates Double Density Design Guide.

3. SA801/901 Track Formats.

2.7 Optional Features

-1 2to -1 5Volt DC to replace -5 Volt DC requirement.

2. Dust Cover, Not available on "FTseries.

3. Write Protect for SA800. Standard on SA801

4. Door Lock. Will lock the door when drive is selected or through alternate I/O pin.

5. Horizontal mounting with door opening up.

6. SA800/801 "R" Series. Allows two drives to be horizontally installed in astandard 19" Ret-

ma rack. Reference figure 20.

2.8 Model Differences

800-1 -Soft Sectored with an FM (single den- l^irz]

sity) data separator.

800-2 -Soft Sectored without data separator.

800-4 -Mechanics only (No PCB).

801 -Hard Sectored with an FM (single

density) data separator and sector

separator.

tOIB

3801

NOTE:

To convert a801 to a800 move the shorting plug from the 801 position to the 800 position. A

800 cannot be converted to a801

3.0 FUNCTIONAL OPERATIONS

3.1 Power Sequencing

Applying AC and DC power to the SA800/801 can be done in any sequence, however, once AC power has

been applied, a 2 second delay must be introduced before any Read or Write operation is attempted. This

delay is for stabilization of the Diskette rotational speed. Also, after application of DC power, a90 millise-

cond delay must be introduced before aRead, Write, or Seek opration or before the control output signals

are valid. After powering on, initial position of the R/W head with respect to data tracks is indeterminant. In

order to assure proper positioning of the R/W head prior to any read/write operation after powering on, a

Step Out operation should be performed until the Track 00 indicator becomes active.

3.2 Drive Selection

Drive selection occurs when adrive's Drive Select line is activated. Only the drive with this line active will

respond to input lines or gate output lines. Under normal operation, the Drive Select line will load the R/W

head, apply power to the stepper motor, enable the input lines, activate the output lines and light the Activity

LED on the front of the drive. Optional modes of operation are available. Reference section 7for these user

installable features.

3.3 Track Accessing

Seeking the R/W head from one track to another is accomplished by:

a. Activating Drive Select line.

b. Selecting desired direction utilizing Direction Select line.

c. Write Gate is being inactive.

d. Pulsing the Step line.

Multiple track accessing is accomplished by repeated pulsing of the Step line until the desired track has

been reached. Each pulse on the Step line will cause the R/W head to move one track either in or out depen-

ding on the Direction Select line. Head movement is initiated on the trailing edge of the Step Pulse.

3.3.1 Step Out

With the Direction Select line at aplus logic level (2.5V to 5.25V) apulse on the Step line will cause the R/W

head to move one track away from the center of the disk. The pulse(s) applied to the Step line and Direction

Select line must have the timing characterisitics shown in Figure 3.

3.3.2 Step In

With the Direction Select line at aminus logic level (0V to .4V), apulse on the Step line will cause the R/W

head to move one track closer to the center of the disk. The pulse(s) applied to the Step line must have the

timing characterisitics shown in Figure 3.

3.4 Read Operation

Reading data from the SA800/801 Diskette Storage drive is accomplished by:

a. Activating Drive Select line.

b. Write Gate being inactive.

The timing relationships required to initiate aread sequence are shown in Figure 4. These timing specifica-

tions are required in order to guarantee that the R/W head position has stabilized prior to reading.

The timing of the read signals, Read Data, Separated Data, and Separated Clock are shown in Figure 5.

DC POWER

DRIVE SELECT

DIRECTION SELECT

TRACK 00

OUTPUT SIGNAL

STEP

90 MS

"MIN

1fiS MIN'

"5 V

^REVERSE

FORWARD

1fiS MIN

i- 12HS4

MAX

rr\

•8MS MIN

1/.s MIN

1fts MIN

DC POWER

DRIVE SELECT

STEP

WRITE GATE

VALID READ DATA'

Figure 3. Track Access Timing

16 MS

MIN

i—35 MS MIN

90 MS MIN*

2SECONDS IF AC AND DC POWER ARE APPLIED AT SAME TIME

50/xS

MIN

Figure 4. Read Initiate Timing

READ DATA

SEP DATA

SEP CLOCK

A= LEADING EDGE OF BIT MAY BE

B=LEADING EDGE OF BIT MAY BE

200 ±50ns

400 ns FROM ITS NOMINAL POSITION.

200 ns FROM ITS NOMINAL POSITION.

Figure 5. Read Signal Timing

3.5 Write Operation

Writing data to the SA800/801 is accomplished by:

a. Activating the Drive Select line.

b. Activating the Write Gate line.

c. Pulsing the Write Data line with the data to be written.

The timing relationships required to initiate awrite data sequence are shown in Figure 6. These timing

specifications are required in order to guarantee that the R/W head position has stabilized prior to writing.

The timing specifications for the Write Data pulses are shown in Figure 7.

3.6 Sequence of Events

The timing diagram shown in Figure 8shows the necessary sequence of events with associated timing

restrictions for proper operation.

DC POWER

DRIVE SELECT

STEP

WRITE GATE

WRITE DATA U—Li

2SECONDS IF AC AND DC POWER ARE APPLIED AT SAME TIME.

Figure 6. Write Initiate Tinning

WRITE DATA CD

150 ns MIN

1100ns MAX -&»

4.00,is ±20ns

2.00/xs

±10ns

Qr—

Figure 7. Write Data Timing

AC POWER

DC POWER

VALID CONTROL

OUTPUT SIGNALS

DRIVE SELECT

2SECMIN 4*

DIRECTION SELECT-

STEP

TRACK

OUTPUT SIGNAL

WRITE DATA

WRITE GATE

VALID READ

DATA SIGNAL

^J.

90MSMIN

"5 V

500 NS MAX

"5S"

0.4/iS MIN

«fr-

90 MS MIN

VsMIN

8MS MIN STEPPRONLY

12/*s MAX

4/xS MAX

90 MS MIN

0.4/tS MIN

—»>

18 MS MIN

^- 35 MS MIN HEAD LOAD

18 MS MIN

nrLT

35 MS MIN HEAD LOAD

90 MS MIN -g^»

~5S

jj$" j

50^s MIN.

NOTE 1: 35ms minimum delay must be introduced after Drive Select to

allow for proper head load settling. If stepper power is to be ap-

plied independent of Head Load, than and 8ms minimum delay

must be introduced to allow for stepper settling. See Section 7on

optional customer installable features.

Figure 8. General Control and Data Timing Requirements

4.0 ELECTRICAL INTERFACE

The interface of the SA800/801 Diskette drive can be divided into two categories:

1. Signal

2. Power

The following sections provide the electrical definition for each line.

Reference Figure 9for all interface connections.

4.1 Signal Interface

The signal interface consists of two categories:

1. Control

2. Data Transfer

All lines in the signal interface are digital in nature and either provide signals to the drive (input), or provide

signals to the host (output), via interface connector P1/J1.

4.1.1 Input Lines

There are ten signal input lines, eight are standard and two are user installable options (reference section 7).

The input signals are of two types, those intended to be multiplexed in amultiple drive system and those

which will perform the multiplexing. The input signals to be multiplexed are:

1. Direction Select

2. Step

3. Write Data

4. Write Gate

The input signals which are intended to do the multiplexing are:

1. Drive Select 1

2. Drive Select 2

3. Drive Select 3

4. Drive Select 4

The input lines have the following electrical specifications. Reference Figure 10 for the recommended cir-

cuit.

True =Logical zero =Vin ±0.0V to +0.4V

@tin =40 ma (max)

False =Logical one =Vin +2.5V to +5.25V

@lin =ma (open)

Input Impedence =150 ohms

HOST SYSTEM

ii-

i" -

DCGND T

FFWS

AC GND

<$-

FLAT RIBBON OR

TWISTED PAIR

MAX 10 FEET

DISK CHANGE*

IN USE'

HEAD LOAD'

™i§8Sa|

INDEX

READY

SECTOR (801 ONLY)

DRIVE SELECT 1

DRIVE SELECT 2

DRIVE SELECT 3

DRIVE SELECT 4

DIRECTION SELECT

STEP

WRITE DATA

WRITE GATE

TRACK 00

WRITE PROTECT (OPTIONAL)

READ DATA

SEP DATA

SEP CLOCK 50

+5VDC

-5 VDC(-7 to -16 VDC)

+24 VDC

+24 VRETURN

AC INPUT

FRAME GROUND

AC INPUT •^m

TWISTED PAIR

SA800/801

FRAME GND

39 -+

41 -O

43 -<)

45 -0

47 0

49 <>

NOTE: Not shown are 5of the 9Alternate I/O connections. The connections for these lines are on

pins 2, 4, 6, 8, 10 and 14. Signal return for these lines are on pins 1, 3, 5, 7, 9and 13 respec-

tively. Reference Section 7for uses of these lines.

*These lines are alternate input/output lines and they are enabled by jumper plugs. Reference

Section 7for uses of these lines.

Figure 9. Interface Connections

4.1.1 Input Line Termination

The SA800/801 has been provided with the capability of terminating the four input lines, which are meant to

be multiplexed, by jumpering traces. The four lines and their respective jumpering traces are:

1. Direction Select Trace "T3"

2. Step , . Trace "T4"

3. Write Data Trace "T5"

4. Write Gate Trace "T6"

In order for the drive to function properly, the last drive on the interface must have these four lines ter-

minated. Termination of these four lines can be accomplished by either of two methods.

1. As shipped from the factory, jumpers are installed on the terminator posts T3, T4, T5, and T6. Remove

these shorting plugs from all drives except the last one on the Interface.

2. External termination may be used provided the terminator is beyond the last drive. Each of the four lines

should be terminated by using a150 ohm, Va watt resistor, pulled up to +5 VDC.

4.1.1.2 Drive Seiect 1-4

Drive Select when activated to alogical zero level, activates the multiplexed I/O lines and loads the R/W

head. In this mode of operation only the drive with this line active will respond to the input lines and gate the

output lines.

Four separate input lines, Drive Select 1,Drive Select 2, Drive Select 3, and Drive Select 4, are provided so

that up to four drives may be multiplexed together in asystem and have separate Drive Select lines. Traces

'DS1 ', 'DS2', 'DS3', and 'DS4' have been provided to select which Drive Select line will activate the inter-

face signals for aunique drive. As shipped from the factory, ashorting plug is installed on 'DS1 '. To select

another Drive Select line, this plug should be moved to the appropriate 'DS' pin. For additional methods of

selecting drives, see section 7.1.

4.1.1.3 Direction Select

This interface line is acontrol signal which defines direction of motion the R/W head will take when the Step

line is pulsed. An open circuit or logical one defines the direction as "out" and if apulse is applied to the

Step line the R/W head will move away from the center of the disk. Conversely, if this input is shorted to

ground or alogical zero level, the direction

of motion is defined as "in" and if apulse is applied to the step line, the R/W head will move towards the

center of the disk.

4.1.1.4 Step

This interface line is acontrol signal which causes the R/W head to move with the direction of motion as

defined by the Direction Select line.

The access motion is initiated on each logical zero to logical one transition, or the trailing edge of the signal

pulse. Any change in the Direction Select line must be made at least 1/*s before the trailing edge of the Step

pulse. The read/write head may be prevented from stepping past track 00 by using the "NFO" trace option

on LSI PCB. Refer to Figure 3for these timings. Note: When going from a reverse seek to aforward seek or

vice versa and additional 8ms delay must be induced before changing direction.

4.1.1.5 Write Gate

The active state of this signal, or logical zero, enables Write Data to be written on the diskette. The inactive

state, or logical one, enables the read data logic (Separated Data, Separated Clock, and Read Data) and

stepper logic. Refer to Figure 6for timings.

4.1.1.6 Write Data

This interface line provides the data to be written on the diskette. Each transition from alogical one level to a

logical zero level, will cause the current through the R/W head to be reversed thereby writing adata bit. This

line is enabled by Write Gate being active. Refer to Figure 7for timings.

4.1.1.7 Head Load (Alternate Input)

This customer installable option, when enabled by jumpering Trace 'C and activated to alogical zero level

and the diskette access door is closed, will load the R/W head load against the diskette. Refer to section 7

for uses and method of installation.

4.1.1.8 In Use (Alternate Input)

This customer installable option, when enabled by jumpering Trace 'D' and activated to alogical zero level

will turn on the Activity LED in the door push button. This signal is an "OR" function with Drive Select. Refer

to section 7.8 for uses and method of installation.

4.1.2 Output Lines

There are six standard and one optional output

lines from the SA800, and eight output lines from

the SA801. Also, there is one Alternate Output

available from the drive. The output signals are

driven with an open collector output stage

capable of sinking amaximum of 40 ma at a

logical level or true state with amaximum

voltage of 0.4V measured at the driver. When the

line driver is off and the collector current is a

maximum of 250 microamperes.

Refer to Figure 10 for the recommended circuit.

+5V

MAX 10 FEET

RIBBON OR

TWISTED PAIR

4.1.2.1 Track 00

Figure 10. Interface Signal Driver/Receiver

The active state of this signal, or alogical zero indicates when the drives R/W head is positioned at track

zero (the outermost track) and the access circuitry is driving current through phase one of the stepper

motor. This signal is at alogical one level, or false state, when the selected drives R/W head is not at track

00.

4.1.2.2 Index

This interface signal is provided by the drive

once each revolution of the diskette (166.67 ms)

to indicate the beginning of the track. Normally

this signal is alogical one and makes the transi-

tion to the logical zero level for aperiod of 1.7

ms (0.4 ms on SA801) once each revolution. The

timing for this signal is shown in Figure 11.

To correctly detect Index at the Host Index

should be false at Drive Select time, that is, the

Host should see the transition from false to true

after the drive has been selected.

166.67 ±3.33 MS

E=lk ^Kl

1.7 ±5MS -*

(0.4 ±.2 MSSA801)

Figure 11. Index Timing

For additional methods of detecting Index, refer to section 7.6.

4.1.2.3 Sector (SA801 only)

This interface signal is provided by the drive 32 times each revolution. Normally, this signal is alogical one

and makes the transition to alogical zero for aperiod of 0.4 ms each time asector hole on the Diskette is

detected. Figure 12 shows the timing of this signal and its relationship to the Index pulse.

For additional methods of detecting Sector refer to section 7.7.

SECTOR

INDEX

5.20 ±.30 MS

—

45-

2.60 ±.50 MS

.4 ±.2 MS

Figure 12. Sector Timing

4.1.2.4 Ready

This interface signal indicates that two index holes have been sensed after properly inserting adiskette and

closing the door, or that two index holes have been sensed following the application of +5V power to the

drive.

For additional methods of using the Ready line, refer to section 7.5.

4.1.2.5 Read Data

This interface line provides the "raw data" (clock and data together) as detected by the drive electronics.

Normally, this signal is alogical one level and becomes alogical zero level for the active state. Reference

Figure 5for the timing and bit shift tolerance within normal media variations.

4.1.2.6 Sep Data

This interface line furnishes the data bits as separated from the "raw data" by use of the internal data

separator. Normally, this signal is alogical one level and becomes alogical zero level for the active state.

Reference Figure 5for the timing. This line is available on the SA801 and 800 Model 1.

4.1.2.7 Sep Clock

This interface line furnishes the clock bits as separated from the "raw data" by use of the internal data

separator. Normally, this signal is alogical one level and becomes alogical zero level for the active state.

Reference Figure 5for the timing. This line is available on the SA801 and 800 Model 1and PCB 25136.

NOTE: True separation internally inserting up to three missing clock bits to maintain synchronization, is

available on the LSI PCB by using trace option "TS".

4.1.2.8 Write Protect (Optional on SA800)

This interface signal is provided by the drive to give the user an indication when a Write Protected Diskette is

installed. The signal is logical zero level when it is protected. Under normal operation, the drive will inhibit

writing with aprotected diskette installed in addition of notifying the interface.

For other methods of using Write Protect, refer to section 7.9.

4.1.2.9 Disk Change (Alternate Output)

Reference section 7.10.

4.1.3 Alternate I/O Pins

These interface pins have been provided for use with customer installable options. Refer to section 7for

methods of use.

4.2 Power Interface

The SA800/801 Diskette Storage Drive requires both AC and DC power for operation. The AC power is used

for the spindle drive motor and the DC power is used for the electronics and the stepper motor.

4.2.1 AC Power

The AC power to the drive is via the connector P4/J4 located to the rear of the drive and below the AC motor

capacitor. The P4/J4 pin designations are outlined below for standard as well as optional AC power.

60 Hz 50 Hz

115 V(Standard) 208/230 V110V 220V

85-1 27 VAC

Frame Gnd

85-127 VRtn

170-253 VAC

Frame Gnd

170-253 VRtn

85-127 VAC

Frame Gnd

85-127 VRtn

170-253 VAC

Frame Gnd

170-253 VRtn

MAX

CURRENT 0.35 Amps 0.23 Amps 0.35 Amps 0.23 Amps

FREQ

TOLERANCE ±0.5 Hz ±0.5 Hz

4.2.2 DC Power

DC power to the drive is via connector P5/J5 located on non-component side of PCB near the P4 connector.

The three DC voltages and their specifications along with their P5/J5 pin designators, are outlined below.

PIN DC VOLTAGE TOLERANCE CURRENT MAX I

RIPPLE (p to p)

1+24 VDC ±1.2 VDC 1.7 AMax**

1.3 ATyp

100 mv

2+24 VReturn*

3-5VReturn

4-5 VDC

Optional

-7 to -16 VDC

(trace 'L')***

±0.25 VDC

0.07 AMax

0.05 ATyp

0.10 AMax

0.07 ATyp

50 mv

5+5VDC ±0.25 VDC 1.0 AMax

0.8 ATyp

50 mv

6+5VReturn

*The +24 VDC power requires aseparate

ground return line. It, and all other DC grounds

must be connected together at the power supp-

ly. One line from this common DC connection

must go to one common Frame Ground connec-

tion near the power supply.

**lf either customer installable option described

in sections 7.2 and 7.4 are used, the current re-

quirement for the +24 VDC is amultiple of the

maximum of +24V current times the number of

drives on the line.

***lf the shorting plug is in the vertical position

the -7 to -1 6VDC option can be used. If the shor-

ting plug is in the horizontal position, -5 VDC

must be used.

-|4 CI3 "}

5.0 PHYSICAL INTERFACE

The electrical interface between the SA800/801 and the host system is via three connectors. The first con-

nector, J1, provides the signal interface; the second connector, J5, provides the DC power; and the third

conector, J4, provides the AC power and frame ground.

This section describes the physical connectors used on the drive and the recommended connectors to be

used with them. Refer to Figure 16 for connector locations.

5.1 J1/P1 Connector

Connection to J1 is through a50 pin PCB edge card connector. The dimensions for this connector are shown

in Figure 13. The pins are numbered 1through 50 with the even numbered pins on the component side of the

PCB and the odd numbered pins on the non-component side. Pin 2is located on the end of the PCB connec-

tor closest to the AC motor capacitor and is labeled 2. Akey slot is provided between pins 4and 6for op-

tional connector keying.

The recommended connectors for P1 are tabulated below.

TYPE OF CABLE MANUFACTURER CONNECTOR P/N CONTACT P/N

Twisted Pair, #26

(crimp or solder) AMP 1-583717-1

583616-5 (crimp)

58354-3 (solder)

Twisted Pair, #26

(solder term.) VIKING 3VH25/1JN-5 NA

Flat Cable 3M "Scotchflex" 3415-0001 NA

KEY SLOT

.400 ±.010"

.050" NOM

050" NOM .100" NOM

2.575 ±.010"

.063"

NOM (2X)

BOARD THICKNESS .062 ±.007'

Figure 13. J1 Connector Dimensions

5.2 J5/P5 Connector

The DC power connector, J5, is mounted on the

non-component side of the PCB and is located

below the AC motor capacitor. J5 is a6pin AMP

Mate-N-Lok connector P/N 1-380999-0. The

recommended mating connector (P5) is AMP

P/N 1-480270-0 utilizing AMP pins P/N 60619-1.

J5 pins are labeled on the component side of the

PCB with pin 5located nearest J1/P1. Figure 14

illustrates J5 connector as seen on the drive

PCB from non-component side.

5.3 J4/P4 Connector

The AC power connector, J4 is mounted on the

AC motor capacitor bracket and is located just

below the capacitor. J4 connector is a3pin con-

nector AMP P/N 1-480305-0 with pins P/N

60620-1. The recommended mating connector

(P4) is AMP P/N 1-480303-0 or 1-480304-0 both

utilizing pins P/N 60619-1. Figure 15 illustrates

J4 connector as seen from the rear of the drive.

©Uo

©©

Figure 14. J5 Connector

Figure 15. J4 Connector

REAR OF DRIVE AC DRIVE MOTOR CAPACITOR

J5 AMP P/N 1-380999-0

J4AMP P/N 1-480305-0

AMP P/N 1-480303-0

AMP P/N 1-480304-0

P1 CONNECTOR

FLAT CABLE

3M P/N 3415-0001

TWISTED PAIR

AMP P/N 1-583717-1

VIKING P/N 3VH25/1JN-5

Figure 16. Interface Connectors -Physical Location Diagram

6.0 DRIVE PHYSICAL SPECIFICATIONS

This section describes the mechanical dimensions and mounting recommendations for the SA800/801.

6.1 Drive Dimensions

Reference Figure 18 for dimensions of the SA800/801

6.2 Mounting Recommendations

The SA800/801 is capable of being mounted in one of the following positions:

1. Vertical-Door opening to the left or right.

2. Horizontal-Door opening up or down.

3. Upright-Door opening towards the front or rear.

6.2.1 Vertical Mounting

The drive, as shipped from the factory, is ready to be mounted in the vertical position, door opening left or

right, without any adjustments.

Horizontal Mounting

If the drive is to be mounted horizontally with the

door opening down (PCB up), the head load ac-

tuator return spring must be repositioned to

compensate for gravity. Reference Figure 17for

the proper spring position on the actuator.

If the door is to open up (PCB down), it must be

specified when ordering. This feature provides a

heavier door opening spring. In addition, the

head load actuator return spring will be reposi-

tioned to compensate for gravity. Reference

Figure 17 for the proper position for the spring

on the actuator.

HORIZONTAL

MOUNTING

(PCB DOWN)

VERTICAL

UPRIGHT

MOUNTING

HORIZONTAL

MOUNTING

(PCB UP)

Figure 17. Head Load Actuator Mounting Prerequisites

6.2.3 Upright Mounting

If the Drive is to be mounted in the upright position (IBM 3740 fashion), the spring hook attached to the eject

mechanism must be removed and then attach the eject spring to the place the hook was on.

QLU

CD •—

CD >

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CD CO

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ECM

CD LO

CM LO

Q«3- mLO +1

EOooCO

QCM CM r^ +1

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joCD 00 ^f •«s(-

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1CD oLO T1— o

Qu^"1 »h-

Fsgure 18. SA800/801 Diskette Storage Drive Dimensions

6.3 Chassis Slide

Available as an optional accessory is achassis slide kit P/N 50239. This kit contains two slides, one locking

and one non-locking, and seven screws. Dimensions of the slide are shown in Figure 19. For use on the stan-

dard casting only.

MIUJIIIO* IIM»"'"l!fflM* *limB''" ^U^"liM« ".HiMM BUM'1''MMfrfflliMlfahyifff'^^

ATTACHED

TOSA800,

.75

Y=TRAVEL ±.06' -S23-HSJ- X= LENGTH ±.03-

4--&

r—

<& I11

75-^»)

«^g~p ^»

LENGTH/TRAVEL VIEW

ffi •$* Tr*"

-G- -^m-

STANDARD MOUNTING

HOLE SIZE .177 DIAM.

XYABCDEFGH

14 15 4.00 8.00 12.00 1.00 3.50 8.50 11.50 12.50

Figure 19. Slide Mounting Dimensions

6.4 Decorative Face Plate

The SA800/801 may be ordered with one of the following decorative face plates:

SIZE COLOR PART NO.

45/8 X10 1/2 Tan 50264

45/8 X10 1/2 White 50263

51/4 X10 Tan 50261

51/4 X10 White 50260

51/4x11 Tan 50258

51/4X11 White 50257

"R" Series-4 5/8 X811/16 Tan 50675

If another color is required to match the system's color scheme, the face plate may be painted. The follow-

ing information should be utilized to avoid potential problems in the painting process.

1. The front cover is made from GE's LEXAN. Dimensional stability of LEXAN exists from -60°F +250°F. If

the type paint used requires baking, the temperature should not exceed +250°F, including any hot spots

which can contact the cover.

2. LEXAN is apolycarbonate. Any paint to be used should be investigated to insure that it does not contain

chemicals that are solvents to polycarbonates.

"CD

'CD TJ

CD 03 CD

OQ. C)

-^ cz -^

cocr

oCO

CD CD

EoF

CO cCO

(J 3o

uLL O

L±_

J*:

CM "*

^Q_

^+1 CM

SLg X

g° CM

r*—450 ±02"^—**l

1.00 ±.01

54 ±.02

CO LO

CO CM

Figure 20. SA800/801R Dimensions

7.0 CUSTOMER INSTALLABLE OPTIONS

The SA800/801 can be modified by the user to function differently than the standard method as outlined in

sections 3and 4. These modifications can be implemented by adding or deleting traces and by use of the

Alternate I/O pins. Some traces are capable of being connected by use of ashorting plug, Shugart P/N 15648

or AMP P/N 5301 53-2. This section will discuss afew examples of modifications and how to install them. The

examples are:

Drive Select one to eight drives.

2. Select drive without loading head or enabling stepper.

3. Select drive and enable stepper without loading the head.

4. Load head without selecting drive or enabling stepper.

5. Radial Ready.

6. Radial Index/Sector.

7. Eight, 16, or 32 Sector option.

8. In Use (Activity L.E.D.) optional input.

9. Write Protect options.

Tabulated below are the trace options with the condition of the trace as it is shipped from the factory. Figure

21 shows the location of these traces on the PCB.

CUSTOMER CUT/ADD TRACE OPTIONS

TRACE

DESIGNATOR DESCRIPTION

SHIPPED FROM FACTORY!

OPEN SHORT

T3,T4,T5,T6 Terminations for Multiplexed Inputs Plugged

T1 Terminator for Drive Select Plugged

T2 Spare Terminator for Radial Head Load X

DS1,DS2,DS3,DS4 Drive Select Input Pins XDS1 is

Plugged

RR Radial Ready X

Rl Radial Index and Sector X

R,I,S Ready, Index, Sector Alternate Output Pads X

HL Stepper Power From Head Load Plugged

DS Stepper Power From Drive Select X

WP Inhibit Write When Write Protected X

NP Allow Write When Write Protected X

8,16,32 8, 16, 32 Sectors (SA801 Only) 8& 16 32

DAlternate Input-In Use X

2,4,6,8,10,12,14,16,18 Nine Alternate I/O Pins X

D1,D2,D4,DDS Customer Installable Decode Drive Select Option X

A,B,X Radial Head Load Plugged

CAlternate Input-Head Load X

ZIn Use from Drive Select Plugged

YIn Use from HD LD X

DC Alternate Output-Disk Change X

NFO Non Force Out X

TS True FM Data Separation X

-*~iR4 f——

R5r*~"

—[HIT

-riitr

-389

Rl?

Big

o-n

-mf

RI6

RI5

II yHi

ftlS

LIO

HR23 hJ2

ca Jumper Plug Installed as Shipped

OTest Point

Figure 21. Component Locations Standard PCB

II+»

HOd-d-d

R.qn

„„ o

DCo

Doo

ioo

'oo

Soo XJ-

DS1 ,™ UL

DS2 |f°°i

DS3 §gT2 9\

DS4 oo

T3 06

66 D-D

00 RR

IIIII

n-n

Rl TS

NFO

i, i, i,

o801

DSo

hl!

lool [ool lool

ABX, .

(ool

D-DD B

WPNP9

12 26

i, i, i, i,i ,

II IIII

ofo'ol

258

izr

i i ii1 1

iiiiFt

I, I, I, I, J.

I, I, I, I,

JJUJU

Figure 22. Component Locations LSI PCB

7.1 Drive Select •One to Eight Drives

Customer installed option allows up to eight

drives to be multiplexed together. This method of

drive selection uses abinary address to select a

drive.

To install this feature on astandard drive, the

following traces should be added or deleted:

Add a74L85, 4bit comparator (Motorola

P/N MC 14585, National Semiconductor

P/N MM 74c85) into position 2B on PCB,

(1Aon PCB 25136).

Connect trace 'DDS'.

Insure traces 'DS1' -'DS4' are plugged.

Jumper traces 'D1\ 'D2\ and 'D4' accor-

ding to table below for address of each

drive.

The four Drive Select lines are to be used for ad-

dressing the drives. Pin 26 is used as Drive

Select enable and pins 28 (binary 1), 30 (binary

2), and 32 (binary 4), are the address lines.

Figure 23 illustrates the circuitry. The table

below shows the logical state each line must be

at to select each of the drives.

Figure 23 illustrates the circuitry.

ADDRESS

TRACE

D1 D2 D4

311

511

611

7111

DRIVE

INTERFACE PIN

26 28 30 32

111

21 1

411

+5VDC O-

DRIVE ADDRESS

2SHOWN

-DRIVE SELECT 4

-DRIVE SELECT 3

-DRIVE SELECT 2

-DRIVE SELECT 1

-3- 00 C\J t-

CO CO CO CO

Q Q QQ

ADDED TRACE

STANDARD TRACE

mDELETED TRACE

DDS

-DRIVE SELECT

Figure 23. Drive Select Circuitry

7.2 Select Drive Without Loading Head Or Enabling Stepper Motor

This option would be advantageous to the user who requires adrive to be selected at all times. Normally,

when adrive is selected, its head is loaded and the stepper motor is energized. The advantage of this option

would be that the output control signals could be monitored (with the exception of Track Zero, which re-

quires the stepper to be energized) while the head was unloaded thereby extending the head and media life.

When the system requires the drive to perform aRead, Write, or Seek, the controller would activate the

Head Load line (pin 18) which in turn would load the head and energize the stepper motor. After the Head

Load line is activated, a35 ms delay must be introduced before Write Gate and Write Data may be applied or

before Read Data is valid.

To install this option on astandard drive, the following traces should be added or deleted:

1. Jumper trace T2\

2. Remove jumper from trace 'X'.

3. Jumper trace 'C.

Figure 24 illustrates the circuitry.

-DRIVE SELECT 4

-DRIVE SELECT 3

-DRIVE SELECT 2

-DRIVE SELECT 1

ALTERNATE

I/O PINS +DRIVE

SELECT

-DOOR CLOSED $

+HEAD

LOAD

__STANDARD TRACE

m/M DELETED TRACE

ADDED OR JUMPERED TRACE

NOTE: If the -Head Load line is multiplexed, terminator 'TV

jumper must be removed from each drive except

the last one on the line. Also, the current require-

ment for the +24 VDC supply should be amultiple

of the maximum +24 volt current times the number

of drives on the line that have Head Load active.

Figure 24. Select Drive Without Loading Head Circuit

7.3 Select Drive and Enable Stepper Without Loading Head

This option is useful to the user who wishes to select adrive and perform aseek operation without the head

being loaded or with door open. An example use of this option is that at power on time, an automatic

recalibrate (reverse seek to track zero) operation could be performed with the drive access door open. Nor-

mally for aseek to be performed, the door must be closed and the head loaded. Other advantages are those

listed in section 7.2 in addition to being able to monitor Track Zero. When aRead or Write operation is to be

performed, the head must be loaded (pin 18). After the Head Load line is activated, a35 ms delay must be in-

troduced before Write Gate and Write Data may be applied or before Read Data is valid.

To install this option on astandard drive, the following traces should be added or deleted:

1. Jumper trace 'T2'.

2. Remove jumper from trace 'B'.

3. Remove jumper from trace 'HL'.

4. Jumper trace 'DS'.

5. Jumper trace 'C

Figures 24 and 25 illustrate the circuitry.

7.4 Load Head Without Selecting Drive Or Enabling Stepper

This option is useful in disk to disk copy operations. It allows the user to keep the heads loaded on all drives

thereby eliminating the 35 ms head load time. The head is kept loaded on each drive via an Alternate I/O pin.

Each drive may have its own Head Load line (Radial or Simplexed) or they may share the same line

(Multiplexed). When the drive is selected, an 8ms delay must be introduced before aRead or Write opera-

tion can be performed. This is to allow the R/W head to settle after the stepper motor is energized. With this

option installed, adrive can only be selected with both Drive Select and Head Load active.

To install this option on standard drive, the following traces should be added or deleted:

1. Jumper trace T2\

2. Remove jumper from trace 'A'.

3. Remove jumper from trace 'HL'.

4. Jumper trace 'DS'.

*5. Jumper trace 'C.

*lf the -Head Load line is multplexed, terminator 'TV jumper must be removed from each drive except the

last one on the line.

Figures 25 and 26 illustrate the circuitry.

+HEAD LOAD

+DRIVE SELECT

NOTE:

FROM STEP

COUNTER

The 8ms delay may be eliminated by

keeping trace 'DS' open. This would

keep the stepper motor energized at all

times. If this is used, the current require-

ment of the +24 VDC supply must be a

multiple of the maximum +24 Volt cur-

rent times the number of drives on the

ne.

>TO STEPPER

Figure 25. Stepper Motor Enable Circuit

-DRIVE SELECT 4-X 32

-DRIVE SELECT 3-* 30

-DRIVE SELECT 2-H 28

-DRIVE SELECT 1-X 26

ALTERNATE

I/O PINS

-HEAD LOAD^

4?\

©^

III

+5VDC

150

;=5 4'+5VDC

18-

W150

O"^S/S^Sf^

-DOOR CLOSED

tT2

+DRIVE

SELECT

+HEAD

LOAD

STANDARD TRACE

WM DELETED TRACE

ADDED OR JUMPERED TRACE

IF THE -HEAD LOAD LINE IS MULTIPLEXED; TERMINATOR 'T1 'JUMPER MUST

BE REMOVED FROM EACH DRIVE EXCEPT THE LAST ONE ON THE LINE.

Figure 26. Load Head Without Selecting Drive or Enabling Stepper Circuit

7.5 Radial Ready

This option enables the user to monitor the Ready line of each drive on the interface. This can be useful in

detecting when an operator has removed or installed aDiskette in any drive. Normally, the Ready line from a

drive is only available to the interface when it is selected.

To install this option on a standard drive, the following traces should be added or deleted:

1. Cut trace 'RR'.

*2. Cut trace 'R\

*3. Add awire from pad 'R' to one of the Alternate I/O pins.

*One of the drives on the interface may use pin 22 as its Ready line, therefore, steps 2 and 3may be

eliminated on this drive. All the other drives on the interface must have their own Ready line, therefore steps

2and 3must be incorporated.

Figure 27 illustrates the circuitry.

+5V

+DRIVE SELECT

+READY

STANDARD TRACE

WM DELETED (CUT)TRACE

ADDED TRACE

-READY

Figure 27. Radial Ready Circuit

7.6 Radial Index/Sector

This option enables the user to monitor the Index and Sector lines at all times so that the drive may be

selected just prior to the sector that is to be processed. This option can be used to reduce average latency.

To install this option on astandard drive the following traces should be added or deleted:

1. Cut trace 'Rl\

*2. Cut trace 'I'.

*3. Cut trace 'S'.

*4. Add awire from trace 'I' to one of the Alternate I/O pins.

*5. Add awire from trace 'S' to one of the Alternate I/O pins.

*One of the drives on the interface may use pin 20 (-Index) and pin 24 (-Sector) as its Index and Sector lines,

therefore, steps 2-5 may be eliminated for this drive. All other drives on the interface must have their own In-

dex and Sector lines, therefore, steps 2-5 must be incorporated.

Figure 28 illustrates the circuitry.

+DRIVE SELECT $-

STANDARD TRACE

#DELETED (CUT) TRACE

ADDED TRACE

+INDEX

©-—^WV"^-i^

+5V

+SECTOR

ALTERNATE

I/O

-INDEX

-SECTOR

Figure 28. Radial Index/Sector Circuit

7.7 Eight, 16, Or 32 Sectors

The SA801 ,as shipped from the factory, is set up to provide 32 Sector pulses per revolution of the Diskette

onto the interface. This option is provided for the user who wishes to have eight or 16 Sectors per revolution.

The logic divides the Sector pulses by two or four. Reference Figure 29 for the timing relationships.

To install this option on astandard drive (SA801), the following traces should be added or deleted:

1. Cut trace '32'.

2. Connect trace '16' for 16 Sectors or connect trace '8' for eight Sectors.

Figure 30 illustrates the circuitry.

INDEX

32 SECTORS

16 SECTORS

8SECTORS

5.2 ±.3 MS

10.4 ±.4 MS

-20.8 ±.6 MS-

*INDICATES BEGINNING OF SECTOR 1IN RELATIONSHIP TO INDEX

Figure 29. Sector Timing Relationships

+SECTOR 5—f

+DRIVE SELECT

-INDEX J

-SECTOR

STANDARD TRACE

DELETED (CUT) TRACE

ADDED TRACE

Figure 30. Sector Divide Circuit

7.8 In Use Alternate Input (Activity LED)

This alternate input, when activated to alogical zero level, will turn on the Activity LED mounted in the push

bar on the front panel of the drive. It can be used as an indicator to the operator. Examples of some indica-

tions are:

1. Write protected Diskette is installed.

2. Drive in which the diskette is to be changed.

3. The operating system drive.

4. Drive with aspecial configuration.

To install this option on standard drive, jumper trace 'D' and active the interface line pin 16.

This signal is an "OR" function with Drive Select or Head Load. Figure 31 illustrates the circuitry.

ALTERNATE

I/O PINS

-DRVSELINT $

-HEAD LOAD J

5.1 K

«AAAr-@ +5V

+IN USE

(TO LED)

Figure 31. In Use/Activity LED Circuit

7.9 Write Protect Optional Use

As shipped from the factory, the optional Write Protect feature will internally inhibit writing when aWrite Pro-

tected Diskette is installed. With this option installed, aWrite Protected Diskette will not inhibit writing, but it

will be reported to the interface. This option may be useful in identifying special use Diskettes.

To install this option on adrive with the Write Protect feature, the following traces should be added or

deleted:

1. Cut trace 'WP\

^2. Connect trace 'NP'.

Figure 32 illustrates the circuitry.

-WRITE PROTECT Jj-

-WRITE GATE J

TO INTERFACE

TO WRITE CURRENT

Figure 32. Write Protect Circuit

7.10 Disk Change (Alternate Output)

This customer installable option is enabled by jumpering trace 'DC. It will provide atrue signal (logical zero)

onto the interface (pin 12) when Drive Select is activated if while deselected the drive has gone from aReady

to aNot Ready (Door Open) condition. This line is reset on the true to false transition of Drive Select if the

drive has gone Ready. Timing of this line is illustrated in Figure 33. The circuitry is illustrated in Figure 34.

-DRV SEL

-READY

-DISKCHG

—5S—

INTERNAL

ENABLE

3!r

*fr

45-

Figure 33. Disk Change Timing

+5V

-READY J°[^>

-DRV SEL 5

fi.

CQ&-

I"X.

I1/

DC 12 12

XDISKCHG

Figure 34. Disk Change Circuit

8.0 OPERATION PROCEDURES

The SA800/801 was designed for ease of operator use to facilitate awide range of operator oriented applica-

tions. The following section is aguide for the handling and error recovery procedures on the diskette and

diskette drive.

8.1 Diskette Loading and Handling

The diskette is aflexible disk enclosed in aplastic jacket. The interior of the jacket is lined with awiping

material to clean to disk of foreign material. Figure 35 shows the proper method of loading adiskette in the

SA800/801 Diskette Storage Drive. To load the diskette, depress latch, insert the diskette with the label fac-

ing out. (See Figure 35). Move the latch handle to the left to lock diskette on drive spindle. The diskette can

be loaded or unloaded with all power on and drive spindle rotating.

Figure 35. Loading SA800/80

When removed from the drive, the diskette is stored in an envelope. To protect the diskette, the same care

and handling procedures specified for computer magnetic tape apply. These precautionary procedures are

as follows:

1. Return the diskette to its storage envelope.

2. Keep cartridges away from magnetic fields and from ferromagnetic materials which might become

magnetized. Strong magnetic fields can distort recorded data on the disk.

3. Replace storage envelopes when they become worn, cracked or distorted. Envelopes are designed to pro-

tect the disk.

4. Do not write on the plastic jacket with alead pencil or ball-point pen. Use afelt tip pen.

5. Heat and contamination from acarelessly dropped ash can damage the disk.

6. Do not expose diskette to heat or sunlight.

7. Do not touch or attempt to clean the disk surface. Abrasions may cause loss of stored data.

8.2 Write Protecting aDiskette

Shugart Media has the capability of being write protected. The write protect feature is selected by the notch

in the media. When the notch is open it is protected; when covered, writing is allowed. The notch is closed by

placing atab over the front of the notch, and the tab folded over covering the rear of the notch. The Diskette

can then be write protected by removing the tab. Refer to Figures 36 and 37.

FOLD OVER BACK

OF DISKETTE

©r)

Figure 36. Diskette Write Protected

.200 +.010-

075R ±.005 -s^C

CZZ)

.150 ±.005

6.175 ±.005

Figure 37. Write Inhibit Notch Specifications

9.0 ERROR DETECTION AND CORRECTION

9.1 Write Error

If an error occurs during awrite operation, it will be detected on the next revolution by doing aread opera-

tion, commonly called a"write check." To correct the error, another write and write check operation must

be done. If the write operation is not successful after ten attempts have been made, aread operation should

be attempted on another track to determine if the media or the drive is failing. If the error still persists the

disk should be considered defective and discarded.

9.2 Read Error

Most errors that occur will be "soft" errors; that is, by performing an error recovery procedure the data will

be recovered.

Soft errors are usually caused by:

1. Airborne contaminants that pass between the read/write head and the disk. These comtaminants will

generally be removed by the cartridge self-cleaning wiper.

2. Random electrical noise which usually lasts for afew ^sec.

3. Small defects in the written data and/or track not detected during the write operation which may cause a

soft error during aread.

The following procedures are recommended to recover from the above mentioned soft errors:

1. Reread the track ten times or until such time as the data is recovered.

2. If data is not recovered after using step 1, access the head to the adjacent track in the same direction

previously moved, then return to the desired track.

3. Repeat step 1

4. If data is not recovered, the error is not recoverable.

APPENDIX A-MODELS AND FEATURES

MODEL DIFFERENCES

800-1 -Soft Sectored with an FM (single

density) data separator.

800-2 -Soft Sectored without data

separator.

801 -Hard Sectored with an FM (single

density) data separator and sec-

tor separator.

NOTE: To convert a801 to a800 move

the shorting plug from the 801

position to the 800 position. A800

cannot be converted to a 801

DRIVE

MODEL

MEDIA

SINGLE

DENSITY

DOUBLE

DENSITY

800-1 SA1 00 SA102

800-2 SA100 SA102

801 SA101 SA103

MEDIA DESCRIPTION

DISKETTE

MODEL PART

NUMBER DESCRIPTION

SA1 00 50417 IBM 3740 Compatible,

Single Density

SA101 50418 32 Sector, Single Den-

sity

SA1 02 50646 Double Denisty M2FM

SA1 03 50708 32 Sector, Double Den-

sity

AC VOLTAGE/FREQUENCY CONVERSION

PRIMARY PART NUMBERS

VOLTAGE

AND

FREQUENCY MOTOR

ASM* MOTOR

PULLEY BELT

115VAC,60HZ 50443 50358 50356

115VAC.50HZ 50443 50357 50355

230VAC.60HZ 50444 50358 50356

230VAC50HZ 50444 50357 50355

*Motor assemblies include -motor, capacitor and

connector.

DECORATIVE FACEPLATES

Size Color Part Numbers

4-5/8x10-1/2 Tan 50264

4-5/8x10-1/2 White 50263

5-1/4x10 Tan 50261

5-1/4x10 White 50260

5-1/4x11 Tan 50258

5-1/4x11 White 50257

Rack Mount 4-5/8x8-11/16 Tan 50675

Radio Shack Hardware Manual SA800 801 Diskette Drive OEM 1977 Shugart Text

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