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60471400

CONTRPL DATA

CORPORATION

NETWORK PRODUCTS

COMMUNICATIONS CONTROL PROGRAM

VERSION 3

REFERENCE MANUAL

0gv&®*\

CDC® COMPUTER SYSTEMS:

255X SERIES

NETWORK PROCESSING UNIT

REVISION RECORD

Revision

A (11/10/76)

B (04/28/78)

C (12/01/78)

D (06/30/79)

E (05/22/80)

F (10/09/80)

G (05/29/81)

Description

Initial release under NOS lj level 438.

?!fXisi?? e?,!?CP i'lf Cycle 34 plus °Ptioi»al minitape corrective code: PSRs 755, 718A,

729, 757, 773, 784, 828, 834, 835.

Revised to include corrective code release, cycles 35, 36, 37; PSRs 257, 275, 710, 726,

Ion' l*Z\ ?oLth^,76^ 7?3' 779' 784' 792' 800' 801» 803» 804> 807 thru 810, 813, 818,

891 921 853 thrU 855' 858' 862' 865' 869' 87°' 8?2' 8?8 thrU 88i' 883'

Revised to CCP 3.2 PSR level 497. This revision obsoletes all previous editions.

Revised to reﬂect PSR level 518.

Revised for CCP release level 3.3, PSR level 528.

Revised for CCP release level 3.4, PSR level 541. Includes PRU interface with Binary

Synchronous Communications TIP and 2780/3780 terminal support. This is a complete

reprint.

/•sSis

^f£$S.

REVISION LETTERS I, 0, Q, AND X ARE NOT USED

©COPYRIGHT CONTROL DATA CORPORATION

1976, 1978, 1979, 1980, 1981

Printed in the United States of America

Address comments concerning this manual to:

CONTROL DATA CORPORATION

Publications and Graphics Division

215 MOFFETT PARK DRIVE

SUNNYVALE, CALIFORNIA 94086

or use Comment Sheet in the back of this manual

<*=weS!V

60471400 G

LIST OF EFFECTIVE PAGES

New features, as well as changes, deletions, and additions to information in this manual are indicated by bars

in the margins or by a dot near the page number if the entire page is affected. A bar by the page number

indicates pagination rather than content has changed.

Page Revision

Front Cover

Title Page

iii/iv

vii

v i i i

1-1

1-2

1-3

1-4

1-5 thru 1-20

2-1 thru 2-37

3-1

3-2

3-3

3-4 thru 3-7

4-1

A-l thru A-41

B-l

B-2

B-3

B-4

B-5

B-6

B-7

B-8

B-9

B-10

B-ll

B-12

C-l th ru C-9

D-l th ru D-3

E-l

F-l

G-l thru G-4

H-l thru H-3

Index-1

Index-2

Comment !Sheet

Mailer

Back Cover

60471400 G iii/iv

y^^K

PREFACE

This manual is intended to provide overview information

concerning the role of the CDC® Communications Control

Program Version 3.4 (CCP) in network processing, and to

describe the functions which CCP provides for the

network.

CONVENTIONS USED

Throughout this manual, the following conventions are used

in the presentation of statement formats, operator

type-ins, and diagnostic messages:

ALN Uppercase letters indicate words, acronyms,

or mnemonics either required by the network

software as input to it, or produced as output.

aln Lowercase letters identify variables for which

values are supplied by NAM or the terminal

user, or by the network software as output.

Ellipsis indicates that the omitted entities

repeat the form and function of the entity last

given.

[ ] Square brackets enclose entities that are

optional; if omission of any entity causes the

use of a default entity, the default is

underlined.

{ } Braces enclose entities from which one must

be chosen.

Unless otherwise speciﬁed, all references to numbers are

to decimal values; all references to bytes are to 8-bit

bytes; all references to characters are to 8-bit ASCII coded

characters.

RELATED MANUALS

The manuals listed below contain additional information on

both the hardware and software elements of the CONTROL

DATA® 255x Series Computer Systems and the CCP and

related software. The Software Publications Release

History serves as a guide in determining which revision

level of software documentation corresponds to the

Programming Systems Report (PSR) level of installed site

software.

Publication

Host Manuals

Network Products

Communications Control Program Version 3

System Programmer's Reference Manual

Network Products

Interactive Facility Version 1 Reference Manual

Network Products

Network Access Methods Version 1 Reference Manual

Network Products

Network Access Methods Version 1

Network Deﬁnition Language Reference Manual

Network Products

Remote Batch Facility Version 1 Reference Manual

Network Products

Stimulator Version 1 Reference Manual

Network Products

Transaction Facility Version 1 Reference Manual

NOS Version 1 Operator's Guide

NOS Version 1 Reference Manual, Volume 1 of 2

NOS Version 1 Reference Manual, Volume 2 of 2

Software Publications Release History

Publication

Number

60474500

60455250

60499500

60480000

60499600

60480500

60455340

60435600

60435400

60445300

60481000

Avx^S.

60471400 G V •

Language Manuals

CYBER Cross System Version 1

Build Utilities Reference Manual

CYBER Cross System Version 1

Macro Assembler Reference Manual

CYBER Cross System Version 1

Micro Assembler Reference Manual

CYBER Cross System Version 1

PASCAL Compiler Reference Manual

State Programming Language Reference Manual

Update Version 1 Reference Manual

NPU Manuals

MSMP Diagnostic Reference Manual

Network Processing Unit (NPU)

Hardware Reference Manual

Operational Diagnostic System (ODS) Version 2

Reference Manual

60471200

96836500

96836400

96836100

60472200

60449900

96700000

60472800

96768410

yX^rtWf^f.

CDC manuals can be ordered from Control Data Corporation, Literature and

Distribution Services, 308 North Dale Street, St. Paul, Minnesota 55103.

This product is intended for use only as described in

this document. Control Data cannot be responsible for

the proper functioning of undescribed features or

parameters.

• vi 60471400 G

CONTENTS

i. INTRODUCTION TO CCP AND NETWORK

CONCEPTS

Network Concepts

Communications Network Overview

Computer Network Overview

Computer Network Products

Network Host Products

Network Access Method

Network Deﬁnition

Network Supervision

NAM Applications Programs

Communications Network Products

255X Series NPU

Communications Control Program

CCP Coding Languages

Message Movement in a Network

Simpliﬁed Input Message Processing

Simpliﬁed Output Message Processing

CCP Role in Network Processing

Multiplexing Operation

Base System Software

Block Interface Package (BIP)

Host Interface Package

Link Interface Package

Terminal Interface Packages

CCP Software Languages

255X Hardware

Communications Processor

Multiplex Subsystem

Communications Console

2558-3 Channel Coupler

Communications Line Adapters

2560 Series Synchronous Communications

Line Adapters

Sample Conﬁgurations

Terminals Supported

2. OVERVIEW OF CCP FUNCTIONS

Multiplexing, Switching and Data Conversion

Interfaces

Transmission Media

Initialization

Base System Software

System Monitor

Buffer Handling

Worklist Services

Queuing Mechanisms

Direct Program Calls (Switching Services)

Interrupt Handling

Timing Services

Globals

Control Block Services

Directory Maintenance

Standard Subroutines

Multiplex Subsystem Operation

Input Multiplexing

Output Multiplexing

Trunk Multiplexing

Demultiplexing

Block Interface Package (BIP)

Block Routing

Service Module

Interactive Virtual Terminal Commands

Batch Terminal PRU Commands 2-9

1-1 Routing 2-9

Block Acknowledgment and Data Flow Control 2-9

1-1 Processing Special Characters and

1-1 IVT Commands 2-9

1-1 Processing Autoinput 2-9

1-2 Common TIP Subroutines 2-9

1-2 Failure and Recovery 2-10

1-2 Host Failure 2-10

1-3 NPU Failure 2-10

1-4 Logical Link Failure 2-10

1-4 Trunk Failure 2-10

1-6 Line Failure 2-10

1-6 Terminal Failure 2-10

1-7 Diagnostics 2-10

1-7 Interface Packages 2-10

1-7 Hardware Used by Interface Packages 2-11

1-7 Software Used by Interface Packages 2-11

1-8 Host Interface Package 2-11

1-9 Micromemory Start and Stop Commands 2-12

1-10 Control Word Transfers 2-12

1-10 Status Word Transfers 2-18

1-11 Data Transfers 2-18

1-11 Link Interface Package 2-18

1-12 Loading/Dumping of Remote NPU 2-19

1-13 Trunk Transmission Priorities and

1-15 Regulation 2-19

1-17 Transmission Assurance 2-19

1-17 Terminal Interface Packages 2-19

1-18 Async TIP 2-20

1-19 Input Processing 2-20

1-19 Output Processing 2-21

1-19 User Interface 2-21

MODE 4 TIP 2-21

1-19 Mode 4 Autorecognition 2-22

1-19 Mode 4 Data Handling 2-22

1-19 Host Interface 2-22

IVT Interface 2-22

Card Reader Interface 2-23

2-1 Printer Interface 2-24

Binary Synchronous Communications (BSC) TIP 2-24

2-1 Terminal Device Selection 2-24

2-3 Batch Input Characteristics of 2780

2-3 and 3780 Terminals 2-25

2-4 Batch Output Characteristics of 2780

2-5 and 3780 Terminals 2-25

2-5 Interactive Input and Output Mode 2-26

2-5 Autorecognition 2-27

2-5 IVT Commands 2-27

2-6 HASP Multileaving TIP 2-27

2-6 Summary of HASP Protocol 2-27

2-6 Protocol Operation 2-28

2-6 Control Blocks 2-28

2-7 Data Blocks 2-28

2-7 Error Handling 2-28

2-7 Data Conversion 2-28

2-7 HASP Input Batch Data 2-28

2-7 HASP Printer Output Data 2-29

2-7 HASP Card Punch Output Data 2-30

2-7 HASP Plotter Output Data 2-30

2-7 HASP Error Recovery Procedures 2-30

2-8 HASP Terminal Start-up and Termination 2-30

2-8 X.25 TIP/PAD SubTIP 2-30

2-9 X.25 Input Sequence 2-31

2-9 X.25 Output Sequence 2-31

2-9 Supported Terminal Classes 2-32

/#^v

60471400 G vu •

Transparent Mode

Autoinput

Parity

Typeahead Input from the Terminal

Block Mode

Backspacing from the Terminal

Cancel Input

Break Key Processing

Formatting on Output

IVT Commands

Build-Time Selections

Message Priorities and Input Regulation

Message Priorities

Input Regulation

Host Interface Regulation

Trunk Interface Regulation

Terminal Interface Regulation

Logical Link Regulation

Upline Data

Downline Data

3. INITIALIZING THE NPU

Load/Dump Phases for Local NPUs

Local NPU Loading

Load File Format

Local NPU Dumping, 2551 NPU

Remote NPU Loading

Remote NPU Dumping

Conﬁguring NPUs

4. FAILURE, RECOVERY, AND DIAGNOSTICS

APPENDIXES

A Coded Character Data Input, Output, and

Central Memory Representation

B Diagnostics

C Glossary

D CCP Mnemonics

E Sample Main Memory Map for NPU

F CCP Naming Conventions

G Terminal Commands and Messages

H NPU Operating Instructions

2-32 INI

2-32

2-32 FIG

2-32

2-32 1-1

2-33 1-2

2-33 1-3

2-33 1-4

2-33 1-5

2-33 1-6

2-33 1-7

2-33 1-8

2-35

2-35 2-1

2-35 2-2

2-35 2-3

2-36 2-4

2-36 2-5

2-37

/^^v

3-1

2-6

2-7

3-1 3-1

3-1 3-2

3-1 3-3

3-2

3-6

3-7 TAB

2-1

4-1 2-2

2-3

2-4

2-5

2-6

A-l 2-7

B-l

C-l 2-8

D-l 2-9

E-l 2-10

F-l

G-l 2-11

H-l 3-1

CYBER Network, Overview of Functions 1-2

Network Host Products 1-3

Network Supervisor Functions 1-5

Communications Supervisor Functions 1-6

Simpliﬁed Input Message Processing 1-8

Simpliﬁed Output Message Processing 1-9

CCP Software Levels l-n

Sample NPU/Peripheral Hardware

Conﬁgurations 1-20

Simpliﬁed NPU Buffered Transfers 2-1

Base Elements of the Multiplex Subsystem 2-8

Functions of a LIP 2-11

Functions of a TIP (not X.25 TIP) 2-12

Comparison of TIP/LIP and X.25 TIP

Functions 2-12

Sample Logical Link Connections (Shown

for Local and Remote NPUs) 2-37

Buffer Availability Threshold Levels

for Regulation 2-37

Load File Format 3-3

Format of 2551 Dump 3-4

Format of Words in Dumps 3-4

Buffer Assignment/Release in NPU 2-2

Interface/Protocol Relationships 2-3

Hardware Used by Interface Packages 2-13

Interface Package Software

Characteristics 2-14

Mode 4 Components 2-21

Mode 4 Terminology 2-21

X.25/PAD TIP and PDN Transfer

Characteristics 2-31

X.25/PAD SubTIP Terminal Classes 2-32

Parity Actions 2-32

CCITT PAD Parameters and Recommended

Settings 2-34

Regulation 2-36

Load/Dump Phases 3-1

• viii 60471400 G

/ £ ^ ! ^ V

INTRODUCTION TO CCP AND NETWORK CONCEPTS

The Communications Control Program (CCP) provides the

software necessary to process data (messages) through the

network communications portion of a Control Data Net

work. As will be described later in greater detail, the

network communications function allows an applications

program in the main computer (a CYBER 70/170, called

the host computer in a network) to process data as if the

program were attached directly to a virtual terminal

connected directly to a CYBER port. Since virtual

terminals can be of only two types, interactive or batch, the

host processing becomes essentially independent of terminal

type.

Minimizing terminal type dependency, as well as removing

many of the terminal switching operations from the host,

frees the CYBER computer to process data efﬁciently in the

manner in which it was designed: as a high-speed, high-

powered processor. As a result of this division of labor, the

host can accommodate many more terminals, terminal

types, and applications programs. Naturally, the host also

processes applications programs more rapidly and with

greater ﬂexibility since it is not burdened with I/O functions

that are better performed elsewhere.

The network communications function, thus removed from

the CYBER computer, is made resident in the Network

Processing Unit (NPU). The NPU is a minicomputer system

resident in a 255x Host Communications Processor and its

associated multiplexing and coupling hardware. The types of

operations performed by the NPU are:

• multiplexing data to/from the numerous terminals

• demultiplexing data and storing it in buffers for

buffered high-speed transfers to/from the host

computer

• converting the numerous terminal protocols into

either an interactive or a batch virtual terminal

protocol; the converse operation is performed for

output operations to terminals

• regulation of the volume of traffic handled

Communications network processing not only relieves the

host computer of most I/O overhead; it also relieves

applications programmers of the need to concern themselves

with terminal characteristics other than the characteristics

of the virtual terminals.

Since it is necessary to know the basic concepts of network

message processing to understand the structure of the CCP

software, this introduction includes a description of the

network and the distribution of network tasks between the

host and the NPUs.

The CCP is itself functionally divided into three software

groups:

• base system software which includes the NPU

operating system: monitor, timing and interrupt

services, initialization, space allocation, and other

general service routines; the multiplexing sub

system is also a part of the base system software

• block interface package (BIP) software: block

formation (PRU or IVT), routing, control and status

processing, hardware conﬁguration control

• other interface packages: the host interface, the

link interface to a remote NPU (if one exists in the

network), and the standard terminal interfaces

(ASYNC, BSC, HASP, Mode 4, X.25 with PAD

subTIP)

NETWORK CONCEPTS

Network products provide effective data-processing services

to terminal users. These services consist primarily of

applications programs written to perform speciﬁc functions.

The applications programs are executed in the host

computer.

Network products are designed to achieve functional separa

tion between the host system services to terminal users, and

the communications equipment software required to inter

connect the host computer and its terminals. This has led to

the concept of viewing the complete network as consisting

of two separate networks, a communications network and a

computer network, with well-deﬁned hardware and software

boundaries between them as shown in ﬁgure 1-1.

COMMUNICATIONS NETWORK OVERVIEW

The communications network includes a set of Network

Processing Units (NPUs) interconnected by communications

lines. Its purpose is to transport blocks of data between the

host computer and terminals. To perform this function, the

NPU presents an interface (represented by a set of proto

cols) to the host computer on the one side and to each

terminal on the other side. Messages are carried in buffers

of data and are transferred to/from the host at channel

speeds. At the terminal interface, messages are transferred

one character at a time at communications line speeds.

The host interface is insensitive to the detailed topology of

the communications network, so that the network may be

either a simple network with a single local NPU or a

network with one local NPU and one or more remote NPUs.

COMPUTER NETWORK OVERVIEW

The computer network includes host computers and termi

nals, the host software associated with network communica

tions, and the applications programs providing services to

60471400 G 1-1

COMPUTER NETWORK

yCOMMUNICATIONS NETWORK "N

HOST

LOCAL

PROCESSOR

NODE

ITERMINALS

USERS

Figure 1-1. CYBER Network, Overview of Functions

the terminal users. The software in each host computer

meets the interface presented by the communications

network on the one side, and in turn presents a standard

interface to applications programs written to use the

network on the other side. In this way, the communications

network is isolated from the applications programs so that it

may be changed without disturbing the applications-level

software.

COMPUTER NETWORK PRODUCTS

The computer network uses the communications network

along with host computer software and possibly terminal

software to interface between terminal users and appli

cations programs in a host computer system.

The major network host product is the Network Access

Method (NAM). Other network host products which execute

as applications to NAM provide standard support of time

sharing, remote batch handling, and transaction processing

for the terminal user.

NETWORK HOST PRODUCTS

The CYBER Network Operating System (NOS) provides the

operational environment and control for the computer

network software. The Network Access Method (NAM)

provides a standard interface between the communications

network and the applications programs executing in the host.

The remaining network host products execute as network

applications programs in the host; all use NAM to commu

nicate with the communications network and with each

other.

The network and communications supervisors are responsible

for the network coordination and control-oriented activities

of the CYBER host computer.

Standard NAM applications programs are provided to support

various user applications environments such as timesharing,

remote batch and transaction processing. User-provided

applications may be added to meet special requirements.

Network Access Method

The Network Access Method (NAM) provides a generalized

method for CYBER applications programs to access the

communications network. Figure 1-2 illustrates this

relationship.

NAM provides a centralized queuing mechanism for

accessing the communications network and a subroutine

package that resides in each network applications program's

ﬁeld length. This subroutine package allows the appli

cations to interface to NAM with CALL/ENTER-type

procedure statements.

1-2 60471400 B

HOST NETWORK OPERATING SYSTEM

NS* UA • • UA

APPLICATIONS

CS* RBF* IAF« TVF» TAF» MCS*

NAM*

•STANDARD NETWORK

APPLICATIONS

NPU

NS NETWORK SUPERVISOR

CS COMMUNICATIONS SUPERVISOR

RBF REMOTE BATCH FACILITY

IAF INTERACTIVE FACILITY

TAF TRANSACTION FACILITY

TVF TERMINAL VERIFICATION FACILITY

UA USER APPLICATION PROGRAM

NAM NETWORK ACCESS METHOD

MCS MESSAGE CONTROL SYSTEM

Figure 1-2. Network Host Products

Procedure statements are provided so that the applications

program can connect to and disconnect from NAM, and can

perform functions for applications programs similar to the

terminals. They allow the installation to control the access

to the communications network for programs executing in

the host computer. Procedure statements also control the

data exchange between the applications program and NAM

buffers. Each applications program may have a number of

logical connections. Each logical connection is associated

with a single terminal or with another applications program.

For each logical connection, NAM maintains a set of control

tables and buffers. These allow NAM to queue data between

the connected terminal and the associated applications

program. NAM itself actually performs the physical I/O

with the communications network.

As various events occur in the network, supervisory mes

sages are passed to the applications program. They may, for

example, inform the applications program of a new logical

connection for a terminal which desires service from it, or

of the fact that some failure has occurred. In the same way,

the applications program uses supervisory messages to

communicate with NAM. For example, an applications

program may wish to disassociate itself from some terminal

with whch it has a logical connection.

This use of supervisory messages between NAM and the

applications program obviates the necessity for a deﬁned

table structure in the applications program's ﬁeld length.

NAM allows the applications program to use the table

structure that is most efﬁcient for it. Additionally, NAM

does not limit the kind of buffering used by the applications

program. The applications program may provide a buffer for

each logical connection; alternatively, it may perform all its

I/O from a single buffer. This allows the applications

programmer maximum ﬂexibility in the design of his

program. NAM is described in detail in the NAM Reference

Manual.

Network Deﬁnition

The CYBER 170 Network Products deﬁne the complete

network:

• The communications network is defined in terms of

hosts and nodes and the physical/logical links

between them.

The computer network is deﬁned in terms

applications programs, lines and terminals.

60471400 G 1-3

Network deﬁnition is provided by a language called the

network deﬁnition language (NDL) which consists of a series

of statements that describe the network. These statements

generate a network conﬁguration ﬁle (NCF), a local

conﬁguration ﬁle (LCF) and a printed output. NCF and LCF

are used by the network host products in establishing,

initiating, operating and controlling the network. The

printed output provides documentation of the network

conﬁguration. NDL is described in detail in the NDL

Reference Manual.

Network Supervision

The following paragraphs describe the network supervisor

and the communications supervisor.

NETWORK SUPERVISOR

The network supervisor (NS) coordinates the activities of the

various network processing units (NPUs) in the communi

cations network.

The network supervisor functions are as follows (see ﬁgure

1-3):

• NS is responsible for loading software into the

NPUs.

• NS superimposes a logical network structure on the

physical structure of the communications network.

Logical links are established between the host and

each NPU with which it is allowed to communicate.

Note, however, that the host communicates with

remote NPUs only through the local NPU. This

minimizes the number of host programs that are

aware of the physical structure of the network.

The host can treat the entire communications

network as a set of front-end NPUs; only NS tracks

the actual physical topology of the network. By

this means, the functions of the computer network

and the communications network are effectively

separated.

• NS also receives reports from the NPUs on the

status of the network. The supervisor takes

corrective action as required. NS operates from a

data base established by the individual responsible

for managing the communications network, the

network operator. This person prepares two ﬁles

for use by NS. One contains copies of the software

for each NPU in the network. The second contains

a description of the conﬁguration of the network.

This latter ﬁle is prepared using network deﬁnition

language. NS also allows the network operator

(NOP) to control and to take the status of the

communications network, either from a terminal in

the network or from the CYBER 170 network

operator's console. NS is described in detail in the

NOS Operator's Guide.

COMMUNICATIONS SUPERVISOR

The communications supervisor (CS) coordinates

network-oriented activities of the host computer.

the

CS operates from a data base established by the individual

responsible for managing the host's use of the communi

cations network, the local operator (LOP). The local

conﬁguration table created by the NDL contains terminal

information which allows CS to establish the physical

conﬁguration and characteristics of the terminals for which

its host is responsible. CS also allows the local operator to

control and to take the status of his portion of the computer

network, either from a terminal in the network or from the

LOP's console.

The primary function of CS is to isolate the applications

programs from the physical conﬁguration of the terminals in

the network. As applications programs make themselves

known to NAM and as terminals connect to the network, CS

establishes logical connections between terminal and pro

gram as shown in ﬁgure 1-4.

Applications programs communicate with terminals using

simple connection numbers irrespective of the location of

the terminals in the network. Logical connections may also

exist between different applications programs.

The network deﬁnition language (NDL) allows various

options on the establishment of logical connections.

• A terminal may be automatically connected to a

given application.

• The user at the terminal may be allowed to select

the application he requires.

• The user may be required to log-in before he is

allowed to access the host computer.

CS use is described in detail in the NOS Operator's Guide.

NAM Applications Programs

NAM applications programs provide users with communi

cations access to host-system resources that satisfy a

variety of processing needs.

REMOTE BATCH FACILITY

The remote batch facility (RBF) provides the capability to

transfer data between ﬁles on a CYBER 170 host-computer

and batch peripherals on terminals in the network. RBF

interfaces to the Network Access Method (NAM) in order to

communicate with its terminals. RBF is described in detail

in the RBF Reference Manual.

INTERACTIVE FACILITY

The interactive facility (IAF) provides the terminal user

with a range of timesharing capabilities. The facility

provides the illusion to the user that he is the only user of

the system. IAF also maintains control of ﬁles created by

the user. Files are presumed private to the user who

created them but can be declared to be common so other

users may access them. Programs may be debugged

interactively by use of IAF. The IAF Reference Manual

gives a detailed description of IAF capabilities.

TRANSACTION FACILITY

The transaction facility (TAF) enables the terminal user to

request a host system to perform a series of pre-deﬁned

tasks, such as checking a customer's credit and recording a

sale, or making a reservation, or recording a deposit/with

drawal/loan payment at a bank. When a transaction has

1-4 60471400 B

NETWORK

OPERATOR

/ CCP s/w I

NDL

rCOMMUNICATIONS

NETWORK

NS - NETWORK SUPERVISOR

NDL - NETWORK DEFINITION

LANGUAGE

Figure 1-3. Network Supervisor Functions

been processed, information (such as status, acknowledg

ment, or veriﬁcation) is returned to the originator. Each

subscriber has a private data base. The subsystem can

contain a specialized data manager for use by the tasks or

the total extended data base management system can be

used. TAF is described in detail in the TAF Reference

Manual.

NETWORK VALIDATION FACILITY

The network validation facility (NVF) protects user applica

tions, and such applications as RBF, IAF, TVF, or TAF,

against unauthorized access by terminal users. NVF

validates each user before granting access to the computer

system or any of its resources.

Validation is based on access permissions deﬁned in a

protected ﬁle. Statistical information and thresholds for

illegal conditions pertaining to log-on and application

requests are maintained, logged and reported for accounting

and security (that is, penetration-detection) purposes.

TERMINAL VERIFICATION FACILITY

The terminal veriﬁcation facility (TVF) provides the user

with an active conﬁdence test (diagnostic) to verify the

correct operation of his terminal. This is accomplished by

sending data to or from the terminal in either a user-deﬁned

or TVF-selected format. Three tests are provided:

• A loopback test sends data entered by the user

back to the terminal.

• A line test sends one full line of data to the user.

• A screen test sends one full screen of data to the

user.

TVF is described in detail in the NAM Reference Manual.

MESSAGE CONTROL SYSTEM

The message control system (MCS) allows the user to queue,

route, and journal messages between COBOL programs and

terminals. By using the Application Deﬁnition Language, an

MCS application can be tailored to ﬁt a user's needs. The

terminal can be switched from MCS to NVF.

60471400 G 1-5

NOL-NETWORK DEFINITION LANGUAGE

CS -COMMUNICATIONS SUPERVISOR

RBF-REMOTE BATCH FACILITY

IAF - INTERACTIVE FACILITY

/r^S,

y^sv

Figure 1-4. Communications Supervisor Functions

COMMUNICATIONS NETWORK PRODUCTS

The communications network allows terminals to access the

host computer via communications lines. The network

products used to implement this access are:

• 255x series Network Processing Unit (NPU) hard

ware which provides for physical connection

between host and terminal. In CCP two varia

tions are possible: local NPUs or local and remote

NPUs.

• Communications Control Program (CCP) which is

the software system in the 255x series NPU

I • Cross System software which supports the

installation, maintenance and modiﬁcation of CCP

via the CYBER host computer. This is a

batch-oriented compiler/run-time system.

255x SERIES NPU

The hardware portion of the communications network

consists of:

• A microprogrammable, 16-bit processor (mini

computer). Main memory contains all the space

necessary to execute programs and to provide

buffers for network data. External (mass) memory

is not used.

• A CYBER channel coupler which provides the high

speed interface between the minicomputer and the

host's Peripheral Processing Unit (PPU). Transfers

over this channel are buffered.

Channel buffers within the NPU provide enough

space to handle an entire message transfer in a

single operation.

^&S\

1-6 60471400 G

J ^ s

yams

NOTE

The host/NPU coupler interface passes

data upline to the host in one of three

formats: interactive virtual terminal for

interactive devices, physical record unit

(PRU) for batch devices, or transparent.

Blocks are received from the host in the

same formats.

A multiplex subsystem consisting of:

A Multiplex Loop Interface Adapter (MLIA)

which controls the input and output multiplex

loops

Individual loop multiplexers (LMs) which

attach to the input and output multiplex loop

on one side and to individual Communications

Line Adapters (CLAs) on the other. The CLAs

provide line-by-line interface compatibility

with the modems attached to terminals or to

remote NPUs.

NOTE

At the interface of the NPU to the lines,

data passes to/from the terminals in a

format (protocol) compatible to the ter

minal. A remote NPU is treated as a

special type of terminal.

COMMUNICATIONS CONTROL PROGRAM

The three major parts of the Communications Control

Program (CCP) are:

• The base system which includes the OPS-monitor,

interrupt handlers, multiplex subsystem, software

and ﬁrmware, timing services, initialization (the

NPU is downline-loaded from the host), space

allocation, program-to-program calls and data

transfers, standard subroutines, text processing,

and error checking.

• Block interface package (BIP) software, which

provides block formation (PRU or IVT), routing,

control and status processing, and hardware

conﬁguration controL

NOTE

Inline diagnostics are provided as part of

CCP. If the customer elects to purchase

a CDC maintenance contract, on-line

diagnostics are provided. Also provided in

the maintenance program are some host-

based applications programs which simpl

ify the use of inline diagnostics.

Interface software. Three standard types of

interfaces are provided:

Host interface package (HIP) supports the

high-speed, buffered channel interface to the

host computer. Data is assumed to be in IVT

or PRU format.

Link interface package (LIP) supports the

local/remote NPU transfers. The remote NPU

collects data from its terminals and formats it

prior to passing the data upline to a local NPU.

This interface uses the CDC Communications

Procedure (CDCCP) protocol.

Terminal interface packages (TIPs). Five

standard TIPs handle transfers for terminals

using interactive modes (ASYNC or X25 with

PAD subTIP), or both batch and interactive

modes (Mode 4, BSC, and HASP).

CCP Coding Languages

For ease in programming the NPU, the programmer can code

his source language routines in PASCAL, an ALGOL-like

language. The Cross system programs are run on the host,

and the principal output is an NPU machine language load

ﬁle which resides in host mass storage. This load ﬁle

contains all of the CCP modules in NPU image format

(including overlays). This ﬁle is used to load the NPU

(remote or local) following an NPU or host failure. The

Cross system is described at the end of this section.

A few common programs are coded in the macro assembler

language. A.special subset of this language, called state

programs, uses a set of specially-deﬁned macrocommands to

process messages on the microprocessing level. Each TIP

contains message conversion programs written in the state

programming language. All programs, regardless of source

language, are included in the host's load ﬁle.

Message Movement in a Network

The basic procedures for upline and downline message

movement are discussed next. Note that the procedures

given are highly summarized. Acknowledgment procedures

are also highly summarized. It is assumed that terminals are

connected through a single NPU.

Simpliﬁed Input Message Processing

Figure 1-5 shows the movement of a message from a

terminal to the host applications program. Solid lines

indicate message (and acknowledgment message) pathways,

dashed lines indicate principal control functions. The major

features of the upline message processing are:

• Some synchronous terminals are polled to find

if the terminal has data ready to send; an

asynchronous terminal sends data when it is ready

• Setting up of multiplex subsystem and buffers when

terminal indicates it has data to send upline

• Collecting all data from this (and all other active

terminals) in a circular input buffer (CIB)

• Demultiplexing data and converting it to a host

compatible format (IVT or PRU). Demultiplexed

data is collected in a block which uses one or more

chained buffers and is called a line-related input

buffer. If code conversion is necessary (such as

EBCDIC to ASCII for interactive data or EBCDIC

to display code for batch data), this is also

accomplished.

• When input buffer is full (that is, the message is

complete), message is validated.

60471400 G 1-7

[terminal I—t*

MUX

CONTROL.

MUX LOOP.

AND MLIA

INPUT DATA

PROCESSOR

HOP)

LINE-ORIENTED

INPUT BUFFER

(MAY BE

CHAINED

BLOCKS)

i©

BLOCK INTER

FACE PROCESSOR

(BIP)

SETS UP INPUT

TRANSFER

RAW INPUT MESSAGE

MULTIPLEXED INPUT

MESSAGE IS PLACED

IN CIRCULAR INPUT

BUFFER

(7) PROCESSES CHARACTERS

v-x ANO DETECTS END OF

MESSAGE. DEMUX AND

CONVERT TO VIRTUAL

TERMINAL OR PRU

FORMAT; TRANSLATES

TERMINAL CODE

IF NECESSARY

(&) VALIDATES MESSAGE AND

PASSES IT TO BIP

SETS UP TRANSFER TO PPU.

©DETERMINES ROUTING

WITH HELP OF DIRECTORY.

REQUEUES MESSAGE FOR

COUPLER. CONTROL TO

HIP

(a) RELEASES INPUT BUFFERS,

^-^ WHEN COUPLER STATUS

SHOWS THAT TRANSMISSION

IS COMPLETE

Figure 1-5. Simpliﬁed Input Message Processing

Message routing is determined and message is

queued to the host coupler. Statistics (a type of

status information that includes both successful

and failure information) are generated for the

transfer.

The coupler transmits the message to the host PPU

and unqueues the message from the coupler.

The host receives the message and connects it to

the applications program.

The NPU ﬁnishes input processing by releasing the

message buffer.

Simpliﬁed Output Message Processing

Figure 1-6 shows the movement of a message from a host

application program to a terminal (downline messages).

Conventions for solid and dashed lines are the same as for

the input message diagram. The major features of the

downline message processing are:

• Interrupt from the host indicates a buffer of data

(message or ﬁle) is ready for transmission. The

data is in PRU, IVT, or transparent format at this

point.

• If the NPU is not already saturated with other,

higher priority tasks (note that output takes prece

dence over input), the host interface package (HIP)

sets up the coupler to receive the message and

assigns a buffer (or chained buffers) of space to be

used as an output buffer for the block.

The message is sent by a buffered transfer from

the PPU through the coupler to the assigned

buffers. The coupler causes the transmission

complete interrupt to the HIP when all of the

message has been received.

The text processor converts the message from IVT

or PRU format to the destination terminal's format

(transmission blocks).

The transmission block is queued to a terminal

control block where the terminal interface package

(TIP) detects that data is available.

• If the terminal is able to output data, the TIP

directs the multiplexer subsystem to output the

message.

• When the terminal has detected the end of mes

sage, it sends an acknowledgment message.

Upon receiving acknowledgment that the message

was received, the NPU terminates the output

operation by sending an acknowledgment to the

host and by releasing the output buffers.

Most of the operations mentioned in the input are described

in more detail later in this section. Since most of these

operations are CCP functions, they are also discussed in

general terms, by individual functions, in section 2.

1-8 60471400 G

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BIP. TIP AND

TEXT PROCESSOR

®[©T

I L

©;© ©! ®;

OUTPUT

BUFFERS

MUX CONTROL.

MUX LOOP,

AND MLIA

©/'©I ©'

©SET BOTH PPU ANO

HIP COUPLER TO

RECEIVE MESSAGE

(Ia) SETS UP 8UFFERS FOR

N-' OUTPUT MESSAGE

©COUPLER SENDS

INTERRUPT WHEN

ALL OF MESSAGE IS

RECEIVED

(2A) NOTIFIES BIP BY

V^ A WORKLIST

THAT MESSAGE

IS IN BUFFER

(2B)0UEUES MESSAGE

^^ TO TERMINAL

USING TCB

f2Cj BIP NOTIFIES TIP

V"^ THAT THERE IS

A MESSAGE IN

THE QUEUE (IF

NECESSARY)

(7) CHECKS TCB FOR

V-' MESSAGE READY

TO TRANSMIT

CONVERTS TO PROPER FORMAT FOR

THIS TERMINAL

DIRECTS MESSAGE TRANSMISSION WHEN

TERMINAL RESPONDS IT IS READY

WHEN ACKNOWLEDGE MESSAGE IS

RECEIVED. THIS INFORMATION IS PASSED

UPLINE TO HOST; BUFFER IS RELEASED

Figure 1-6. Simpliﬁed Output Message Processing

CCP Role in Network Processing

The CCP must provide the following functions for the

network system.

• Host interface compatibility: Data is transferred

(upline and downline) in high-speed buffered

transfers. The data is in PRU, IVT, or transparent

format. The host interface package (HIP) monitors

this operation.

• Transfers may be regulated; that is, if the NPU is

busy with output (downline) processing or has many

upline messages already started, new upline trans

fers may be refused. The rejected transfers will be

made at a later time when the NPU is less busy.

• NPU must pass an acknowledgment message to the

host after a terminal has received a downline

message.

• NPU must prepare the coupler for upline and

downline transfers.

• Conversion: Non-transparent upline messages are

converted from terminal format to IVT format (if

the message originated from an interactive

terminal) or to PRU format (if the message

originated from a batch device). Non-transparent

downline messages are converted to the format of

the destination terminal. The TIPs contain

transform tables for code conversion and some

format conversion. The BIP is responsible for some

of the format conversion between terminal and IVT

or PRU format.

The CCP must supply memory space in the form of

chained input and output buffers.

Supervision of the multiplex subsystem. On output,

supervision consists of preparing the multiplex

subsystem to output data from the output buffer.

Actual transmission is done on demand from the

communications line adapter (CLA). On input this

consists of preparing the CLA to receive data.

After the data has been placed on the input loop,

the multiplex loop interface adapter (MLIA) trans

fers the data to the circular input buffer (CIB).

From the CIB, data must be individually demulti

plexed to the line-oriented input buffers.

If this system has a remote NPU as well as a local

NPU, the remote NPU must have a link interface

package (LIP) which collects the data and the local

NPU must have a LIP for receiving the data. In

the remote unit (for upline messages) the data is

collected and converted by the appropriate TIP

into PRU or IVT format (transparent data is I

permitted). The completed message is then divided |

into subblocks of a size suitable for transmitting

over the trunk. In the local NPU the subblocks are

reconstituted into a message buffer. This

data—after validation—is passed to the HIP to be

transferred to the host.

The output operation is the converse of the above I

procedure: that is, blocks of PRU, IVT, or I

transparent data are broken into subblocks (if |

necessary), and multiplexed prior to transferring

the message over the trunk. Conversion to

terminal format takes place in the remote NPU.

60471400 G 1-9

Physical placement of the CLA in the NPU cabinet

determines the frequency with which the line has

access to the multiplex loop. CLAs for lines

assigned to trunks are placed in the ﬁrst slot (or

slots) so that these lines have ﬁrst chance to use

the multiplex loop.

Terminal interface packages (TIPs) are responsible

for setting up the messages so that the terminal

protocols for starting, stopping, acknowledging,

and message formatting are satisﬁed. The TIP also

converts data from host codes (ASCII for IVT;

ASCII or display code for PRU) to the terminal's

internal code, if necessary.

Multiplexing Operation

The multiplex subsystem has two major functions, both of

them hardware related:

• Physical line characteristics vary for the different

types of lines. To relieve the TIPs of having to

process each line type according to that line's

special physical characteristics, the multiplex sub

system handles the characteristics by translating

logical line commands/status into physical line

command/status. This makes most physical line

characteristics transparent to the TIP.

• The high-speed host works most efficiently if given

a full block of data to process. A terminal, on the

other hand, is often low-speed, and data is trans

ferred to/from the terminal one character at a

time. The multiplex subsystem interfaces the high

speed characteristics of the host/NPU with the

"low-speed characteristics of the lines/terminals.

The multiplex interface to the TIPs is described in the

System Programmer's Reference Manual.

INPUT MULTIPLEXING

Each line has a communciations line adapter (CLA). The

CLA for each active line is sampled in sequence. If a

character is ready, it is placed on the input multiplex loop

together with information identifying the source (line) and,

in some cases, control information. All input multiplex loop

data is routed to a circular input buffer (CIB). The

demultiplexing operation picks data from this buffer, recon

stitutes the messages in data buffers, and passes these

buffers to the appropriate processor for this terminal (line).

OUTPUT MULTIPLEXING

After the NPU has received a full message from the host

and the appropriate terminal interface package (TIP) has

converted the code to real terminal format, the multiplex

subsystem can output the message. The multiplex

subsystem picks the characters from the line's output

message buffer in response to an output data demand (ODD)

generated by the CLA. The ODD signal is the CLA's

indication that it is ready to transmit another character.

The outgoing characters are placed on the output multiplex

loop, along with such control characters as are needed and

an address that will be recognized by the CLA connected to

that terminal. The CLA for the line picks the data from the

output loop via the loop multiplexer. When the contents of

the entire output buffer for the line have been transmitted

successfully, the message buffers are released. Many output

data buffers can be serviced at the same time.

TRUNK MULTIPLEXING

If a remote NPU is included in the network, transmissions

between the local NPU and the remote NPU take place over

a trunk. A trunk is a communications line. In the local

NPU, a link interface package (LIP) sets up the output

buffer. In the remote NPU, the downline messages are

treated similarly to upline messages in a local NPU; that is,

the message goes through the CIB and is then demultiplexed

for the TIP. After the TIP converts the code to terminal

format, the message is treated as an output message in a

local NPU; that is, the message is transmitted through the

multiplex subsystem.

Input messages (upline trafﬁc) are reformatted from

terminal to IVT or PRU format as in a local NPU, but are

then sent by the LIP through the remote NPU's multiplex

subsystem, received by the local NPU's multiplex subsystem,

and reconstructed into complete messages in the local NPU

by that NPU's LIP.

DEMULTIPLEXING

The multiplex subsystem is responsible for picking data from

the CIB as well as putting it into that buffer. When the

message reception starts, the multiplex subsystem ﬁrmware

reserves a data buffer for the message. The data words for

that line are picked from the CIB and are packed into the

reserved buffer. Control and tag information is discarded.

If a buffer is ﬁlled before the message is complete, another

buffer is assigned and is chained to the ﬁrst.

When the end of text is detected, the TIP which is

appropriate for the terminal type is called to continue the

processing.

The demultiplexing of a downline transfer is a terminal

function; that is, the message is reconstituted in a buffer for

the screen, printer, or other output device.

Base System Software

The base system software, which includes the multiplex

subsystem, is a basic, relatively invariant, set of CCP

programs. As ﬁgure 1-7 shows, CCP software belongs to

one of three levels:

• base system software

• network communications software

• interface packages (TIPs, LIP, HIP)

The primary functions supplied by the base system are:

• basic operating system functions such as interrupt

handling, calling program (queuing requests), allo

cating space (buffers) to requesting programs,

handling the passing of parameters from the calling

to the called program (worklist processing), timing

services, common areas, and control block services

• some initialization processing

• multiplex subsystem including the command driver

which interfaces between the multiplex subsystem

(software and hardware) and the TIPs or LIP

A ^ S

jiSSS.

1-10 60471400 G

INTERFACE PACKAGES (APPLICATIONS)

•Host Interface Package (HIP)

1•Block Interface Package (BIP)

•Link Interface Package (LIP)

•Terminal Interface Packages (TIPs):

• Mode 4 TIP

• Async TIP

• HASP TIP

• X.25 TIP with PAD subTIP

• BSC TIP

• User Generated TIPs

NETWORK COMMUNICATIONS SOFTWARE

•Routing

•Service message handling

•Virtual terminal transformation

•Diagnostics

•Common TIP subroutines

BASE SYSTEM

•Operating system (space allocation, calls,

interrupt handling)

•Multiplexer subsystem

•Interprogram communications (worklist)

•Timing services

•Standard subroutines

•Internal processor maintenance

Figure 1-7. CCP Software Levels

Conversion to and from IVT or PRU format is done by the

BIP and the TIPs. By this means, host applications need

expect only three data formats: IVT from any interactive

terminal; PRU from any batch device, or transparent data

from any terminal so long as either the terminal or the

application has speciﬁed that the next transmission will be

in transparent format.

An option allows data to be passed to/from the host

applications program in terminal format. (This is called

transparent mode.)

Although the converted data is placed in a new buffer, the

block identity is not lost; data blocks remain logically

invariant regardless of the number of conversions that

occur.

Since the block format itself provides only a limited set of

commands, one type of block called a CMD block is

dedicated to handling the large number of speciﬁc

commands needed to set up the connections of the network

and to handling data ﬂow over these connections. If the

information carried by these command blocks is primarily to

establish, change, or delete connections (a process known as

conﬁguring the network), the message is called a service

message and is handled by the service module. Service

messages are used to:

• configure logical links, trunks, lines, and terminals

• command loading or dumping of the NPU

• carry status concerning failure and recovery

• command on-line or inline diagnostics or debugging,

or carry information about such processes

• command that a message be broadcast to one

terminal or several terminals (including sending a

message from a terminal to the network operator's

(NOP) or local operator's (LOP) terminal)

• common subroutines such as those for code

conversion

Most base subroutines are written in PASCAL language; a

few are written in CYBER 18 macro assembler language.

Block Interface Package (BIP)

The next level of CCP software is concerned with handling

network communications. It provides block switching so

that the data block can ultimately be routed downline to the

proper terminal, or upline to the host. Data traveling in

either direction is tagged with the terminal ID. A group of

directories is used to route the block to the next program

that must process the block.

Transfer of information (messages or ﬁles) through the

host/NPU part of the network is accomplished by

transmitting the data in blocks (this is called block protocol

throughout this manual). A number of block types are

deﬁned. Two block types are dedicated to data transfer;

the remaining block types contain control information such

as acknowledging messages, controlling data ﬂow on a

connection, or starting and stopping transmissions.

Host Interface Package

The host interface package (HIP) handles the protocol

governing transmissions between the host and the NPU. The

route of all such transmissions is through the coupler

hardware. Three coupler registers hold status or command

information; one register contains the NPU address of the

data to be transferred, and one set of lines connects the host

PPU buffer to the direct memory access buffer register of

the NPU. This set of lines handles all data transfers.

In all cases the format of the byte in the host PPU is 12 bits

and the associated half-word (byte) in the NPU is 8 bits.

Adjustment is made so that the receiving unit (host or NPU)

has an input only as large as its input word or byte size.

Usually, the NPU memory address register is set up by the

NPU for upline or downline data transfer. When dumping

the contents of the NPU to the host the PPU sets up the

Four principal functions are performed across the interface.

MICROMEMORY START AND STOP

Micromemory start and stop commands are issued by the

host. The micromemory must be started at location zero.

60471400 G 1-11

CONTROL WORD TRANSFERS

The NPU sets function commands to the coupler, allowing

the coupler to chain buffers of data during transfer, to clear

the coupler registers, to read the other status registers, to

ready the PPU to read the status registers, and to set the

memory address register prior to starting a data transfer.

The PPU sets functions to clear the coupler or NPU, to start

or stop the NPU, to input or output a program during the

load/dump phase of NPU initialization, to load the memory

address for dump operations, and to set or read the other

two status-type registers.

STATUS WORDS

One status word is used for regulation. There are four

regulation levels: (1) to transmit all messages to the NPU,

(2) to transmit all but messages for batch-type devices, (3)

to transmit only service messages, and (4) to transmit no

messages. Regulation is a function of the availability of

NPU buffers to receive input messages.

DATA TRANSFERS

For downline transfers, the NPU assigns the next data

buffer, sets up buffer chaining, if necessary, and switches

the block to the proper internal handling or terminal/-

line/TIP.

For upline transfers, when the full message is ready, the

NPU makes the address of the ﬁrst buffer in the chain

available. When one buffer is transferred, the starting

address of the next chained buffer is provided by the coupler

hardware. This continues until the full message is

transmitted.

Since the DMA/PPU buffer channel is half-duplex (data can

be sent in only one direction at a time), contention for

channel use is normally resolved in favor of outputting

blocks from the PPU. However, following this transfer, the

protocol provides a short period during which the NPU can

request channel use without the PPU contending for channel

use.

No attempt is made to retransmit data in anything less than

a full block. When a bad block is rejected, the entire

message is rejected and must be retransmitted in its

entirety.

Link Interface Package

Since the link interface package (LIP) handles transmission

and reception on both ends of a trunk, a copy of the LIP is

required in both the local and the remote NPU.

Two major types of operations are handled by the LIP:

loading/dumping the remote NPU, and processing data

transmissions over the trunk. Data message transmissions

across the trunk use a unit called a trunk transmission frame

(TTF or frame).

There are three types of frames:

• unnumbered frames which establish the basic trans

mission states between the two nodes (such as

initialization, disconnect, command rejected)

• supervisory frames that establish whether trans

mission/reception is currently possible (ready for

data/not ready for data/rejected last data sent)

• information frames used to transmit message data;

this class of frames includes frames that are

carrying service messages

Both frame size and data block size are customization time

selections. The information frames themselves are com

posed of one or more subblocks. Each subblock is a buffer

of information related to a single message so that the

frame may be considered as a packet of information

subblocks contaning one or more message parts for one or

more terminals.

Either end of the link may initiate data transmission when

conditions warrant. Once the interfacing LIPs have

established the normal mode, data transmission can begin.

A remote NPU has no coupler to the host, and therefore no

HIP. Terminal data passes through the multiplex subsystem

of the remote NPU twice: once as it passes between the

terminal and the NPU, and once as it passes between local

and remote NPUs. Upline data in the remote NPU is

demultiplexed and passed to the appropriate TIP for

conversion. Completed, converted messages are passed to

the LIP for framing and then passed through the multiplex

subsystem, over the trunk to the local NPU. Trunk

transmission rate is up to 19.2 Kbps.

In the local NPU, upline data from the trunk is received by

the LIP and reconstructed into a message in data buffers.

Then it is passed to the HIP for transmission to the host.

Downline data is taken from a message data buffer,

assembled into frame format by the LIP, and sent to the

remote NPU. Once it is demultiplexed by the

LlP/multiplex subsystem, it is ready to be passed to the

appropriate TIP for conversion to terminal format.

LOADING/DUMPING OF REMOTE NPU

The local NPU processes the load/dump operation in its

overlay area. The program information is transmitted

to/from the local NPU overlay area in block form. The

local LIP passes the programs (downline) and receives the

dumped main memory contents (upline) in frame format.

The remote NPU LIP is responsible for stripping the frame

information from the downline subblocks and loading these

subblocks (parts of programs) at the location indicated by

the host. For dumping, the LIP is responsible for placing

the main memory contents (starting at the address

indicated by the host) into frames and sending the frames

to the local NPU.

Conﬁguring the remote NPU is handled by service

messages, as in the case of conﬁguring a local NPU. The

service messages are transmitted across the trunk in the

same manner as any other message data.

TRUNK TRANSMISSION PRIORITIES AND REGULATION

A high or a low priority is assigned to each subblock. High

priority is associated with interactive terminals and low

priority is associated with batch terminals. Each time a

new frame can be transmitted the LIP scans the high and

low priority queues. If high priority data is waiting, it is

always transmitted ahead of low priority data.

On input (in either the local or the remote NPU), data can

be rejected if the number of available buffers has dropped

to the threshold level. First low-priority trafﬁc is

rejected, then high-priority trafﬁc. Supervisory frames are

not included in this priority scheme. These frames contain

some command/status information, but do not include most

service message instructions which are treated as high

1-12 60471400 G

priority. Thus, during regulation, some command/status

information can be rejected while other command/status

information passes over the trunk.

TRANSMISSION ASSURANCE

The CDCCP protocol requires that each frame be

acknowledged. Since several frames may have been

transmitted before a negative acknowledgment for a given

frame is generated, all frames up to and including the last

properly acknowledged frame are retransmitted. No frame

is released from the sending NPU until it is properly

acknowledged. Frame checking is provided by a cyclic

redundancy checksum (CRC) which is generated by the

sending CLA and included at the end of each frame.

Several OPS-levels: The X.25 TIP uses one

OPS-level to supervise protocol/terminals, another

to control packet ﬂow (related to connections

between host applications and terminals), a third to

control frame ﬂow (related to the connection

between the CDC network or the X.25 public data

network), and a fourth (called a sub-TIP) to handle

the format conversions.

ASYNCHRONOUS TIP

The asynchronous TIP supports dedicated and dial-up asyn

chronous lines. The TIP provides software support for most

teletypewriter-like terminals. The interface format

between the host and the TIP is handled by the interactive

virtual terminal and user interface.

Terminal Interface Packages

A terminal interface package (TIP) interfaces the terminal

data (messages) to the network. The terminal interface is

processed through the multiplex subsystem; the system

interface is processed through the line control blocks (LCBs)

and terminal control blocks (TCBs). Five standard TIPs can

be included in a system:

• An async (asynchronous) TIP either in normal or

extended format. This handles only interactive

data.

• A binary synchronous communication (BSC) TIP

that handles both batch and interactive data.

• A synchronous TIP for HASP workstations that

handles both batch and interactive data.

• A Mode 4 (synchronous) TIP which processes data

from both batch and interactive devices.

• An X.25 (synchronous) TIP with a packet handling

(PAD) subTIP. This handles only interactive data

that arrives through a public data network.

Each TIP handles the protocol level for its terminal type.

Specialized additional information for the connection is

contained in the LCB, the logical channel control block

(LCCB), and the TCB. The software portion of a TIP is

written on several levels:

• One or more OPS-levels control message transfer,

including major error (transmission failures)

processing, transfer setup, and transfer

completion. Code and format translation are

controlled by an OPS-level.

4 A mux-2 level is occasionally used for error

processing.

• One or more microprocessing (firmware) levels

perform upline/downline text processing and

demultiplex upline messages.

A number of OPS-levels exist; standard TIPs are written on:

• A single OPS-level: The async TIP uses one

OPS-level to control message ﬂow, error checking,

and code/format translation.

• Two OPS-levels: The Mode 4, HASP, and BSC TIPs

use one OPS level to control code/format

conversion of blocks. Another OPS-level controls

message ﬂow.

The asynchronous TIP supports a terminal-to-virtual trans

form for eight types of terminals. To expand the usefulness

of this TIP, a method is provided for the user at a terminal

or a connected application to vary parameters and operating

modes for any of the eight terminal types. This provides

service for terminals which may differ from the eight

terminal types.

Line types supported are:

• dedicated or dial-up

• two or four-wire

• full-duplex

The TIP is prepared to receive input at all times and

attempts to deliver output whenever available, unless input

is currently active. When input is detected during output,

the TIP suspends output. This output is sent later. All input

and output is converted between the terminal and virtual

terminal characteristics.

The TIP provides an auto-recognition feature for each line.

The result of this feature is a service message from the TIP

informing the host of the line speed. For the 2741 terminal,

the TIP provides code recognition. Several parity options

are provided, and paper tape input/output is supported.

MODE 4 TIP

The Mode 4 TIP interfaces with devices using Mode 4A or

4C protocols. A typical Mode 4 device would be the card

reader, printer, keyboard, and CRT of a CDC 200 user

terminal (UT).

Interactive data is exchanged with a host application in IVT

format; batch data is exchanged in PRU block (PRUB)

format.

The TIP is insensitive to line speeds; it supports synchronous

lines operating at rates up to 9600 baud. Lines may be

dedicated (with or without a transceiver) or switched (dial-

up) with a modem. All lines are considered to be half-

duplex.

Each line may have more than one cluster of equipment and

each equipment cluster may have more than one terminal.

Lines with multiple clusters must be dedicated.

The TIP performs auto-recognition when requested by the

host. Auto-recognition causes the TIP to return a service

message to the host which contains information on terminal

type, cluster address, terminal address, and device type.

Multi-cluster auto-recognition is not supported.

60471400 G 1-13

The Mode 4 TIP supports remote batch terminals as separate

but dependent devices.

The TIP polls the terminal to determine when data should be

sent.

The TIP performs recovery for line or terminal errors. Any

error from which an immediate recovery is not possible is

reported to the host.

The Mode 4 TIP counts all lines of batch output data sent to

a terminal and all card images of batch data sent to the

host. When a batch ﬁle or device connection is terminated,

this data (called accounting data) is fowarded to the host to

be merged with host usage accounting data.

BINARY SYNCHRONOUS COMMUNICATIONS (BSC) TIP

The BSC TIP provides data interchange between a host

application program and a remote IBM 2780, 3780 or

compatible batch terminal. The TIP provides batch and

interactive capabilities. The interactive console is

simulated by accepting input from the card reader and

sending output to the line printer.

Exchange of information between the NPU and a terminal

uses the point-to-point binary synchronous communications

protocol with contention resolution. Batch devices

communicate with host applications using PRUB format;

interactive data uses IVT blocks. The normal code of a

2780/3780 is EBCDIC; transparent mode is permitted.

BSC terminals can be attached to an NPU through dedicatee

or dial-in synchronous lines operating at speeds up to 19200

bps. A terminal consists of a required card reader, a

required line printer, and an optional card punch.

BSC input devices have precedence over output devices and

interactive devices have precedence over batch devices.

For non-transparent line printer output, the TIP supplies

appropriate carriage control transformations (format

effector processing). The host can supply preprint or

postprint format effectors; BSC terminals support only

postprint carriage controls.

A print message (PM) in the output stream to a printer stops

the batch output and allows the host to send an interactive

output message to the printer.

Autorecognition allows the terminal to report its own type,

cluster address, and terminal address. The terminal address

is used for the optional card punch.

HASP MULTILEAVING TIP

The TIP provides network interfacing to a HASP multi-

leaving-type of terminal which may contain both interactive

and batch devices. These terminals have computer-like

functions.

The basic element of multileaving transmission is a

character string which is embedded in a data (message)

block. One or more character strings are formed from the

smallest external element of transmission—the physical

record.

The transmitting program segments the data to be trans

mitted into an optimum number of character strings. The

receiving program reconstructs the original record for

processing. Multiple physical records of various types can

be grouped together in a single transmission block. Multi-

leaving allows for two computers to exchange transmission

blocks containing multiple data streams in an interleaved

fashion. For optimum use of this capability, the system

controls the ﬂow of one data stream while continuing

normal transmission of others. To meter the ﬂow of

individual data streams, a function control sequence (FCS) is

added to each block.

Error detection and correction information are also

provided.

Protocol Operation - After the communications line is

initialized and the terminal is signed on, the NPU and the

terminal transmit idle blocks until a function is desired. The

process initiating the function transmits a request to

initiate; the receiving process transmits permission to

initiate. The requesting process then transmits data until an

EOF is encountered. To transmit more data, the request to

initiate must be repeated.

Data blocks are transmitted one block at a time. Before

another block can be transmitted, the receiving process

must transmit a positive response.

Console functions (operator messages/commands) do not

follow the request-to-initiate/permission-to-initiate

sequence. A console function may be initiated at almost any

time.

The following errors are recognized: cyclic redundancy

check (CRC) errors, illegal block format, unknown

responses, timeouts over the line, and a break in the

sequence of transmitted blocks.

For bad downline data, the TIP attempts to retransmit the

block three times. On the fourth failure, the TIP forces a

line inoperative status on the terminal.

For upline data, the NPU attempts to receive a bad block

four times. On the fourth failure, the TIP forces a line

inoperative status on the terminal.

Data Conversion and Compression - HASP terminals

normally use EBCDIC code. Interactive data is exchanged

with application programs in the host which use ASCn code

in IVT format. Batch data is exchanged with applications

programs which use display code in PRU format. In either

case, the TIP makes the required format and code

conversions. Transparent data is allowed in batch mode.

Data compression is allowed in both transparent and

non-transparent modes.

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The term multileaving describes the computer-to-computer

communciations technique used by a HASP terminal. The

system uses fully-synchronized, pseudo-simultaneous,

bidirectional transmission of a variable number of data

streams between two computers and requires binary syn

chronous communications facilities. In this conﬁguration,

the multileaving capability is used only in the upline

direction.

HASP Console - The HASP console data is handled by the

IVT. Auto-input is permitted.

The HASP TIP accounts for all batch data exchanged with a

terminal, including data sent in transparent mode to the

plotters. When a batch ﬁle or device connection is

terminated, this accounting data is fowarded to the host to

be merged with other host usage accounting data.

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1-14 60471400 G

X.25 TIP WITH PAD SUBTIP PASCAL LANGUAGE/CCP SUPPORT SOFTWARE

The X.25 TIP with the packet assembly/disassembly (PAD)

subTIP interfaces a NOS network to selected TTY-type

terminals which are attached to an X.25 network. The

connection between the X.25 network and the NOS network

is handled using a data movement protocol similar to that

used by the LIP to connect local and remote NPUs.

The terminals must use ASCII code, but can be attached to

dial-up or dedicated lines. The interface format between

the host and the subTIP is handled by the interactive

virtual terminal. Terminals are also supported in trans

parent mode.

This TIP operates on several levels:

• A subTIP level that interfaces the IVT format

required by the host to the ASCII packet format

required by the PAD subTIP. Packet charac

teristics are governed by the PAD access portion of

the X.25 network.

• A packet handling level that interfaces to the

packet transmission and reception requirements of

the X.25 network's PAD access.

The support software for CCP is called the CYBER Cross

System. It consists of the following programs:

• PASCAL Compiler

• Macro Assembler

• Micro Assembler

• Load-File Build Utilities

Additionally, one more program is provided for CCP support:

• UPDATE: a program for maintaining source decks

in a conveniently compressed format

The support software operates on a host computer, and the

principal output is the CCP load ﬁle which resides on host

mass storage, and which is available to load and initialize

the NPU in the network.

The source language, PASCAL, was chosen to simplify

coding for the NPU microprocessor, which would otherwise

use the relatively low level 1700 source language.

• A frame handling level that interfaces the X.25

network's high-speed data transmission and

reception requirements.

PASCAL Compiler - The PASCAL language is deﬁned in

detail in the CYBER CROSS System PASCAL Reference

Manual. Important aspects of the language are summarized

here.

CHANGES REQUIRED TO WRITE A NON-STANDARD TIP

Any programmer desiring to write his own TIP should use the

CCP System Programmer's Reference Manual so that he

may understand, in detail, the functions CCP must provide

to interface a terminal to a host applications program.

The State Programming Reference Manual provides a

description of the microcode necessary to write the micro

code portion of the TIP.

PASCAL is a high-level programming language patterned

after ALGOL 60. The PASCAL user deﬁnes the task in

statements that are processed by the compiler to yield a

variable number of actual program instructions.

The PASCAL source language consists of two essential

parts:

• description of actions to be performed

• description of data on which actions are performed

CCP Software Languages

CCP programs and routines are written in one of three types

of source code:

• PASCAL language: This type of source code is

used to write the bulk of CCP programs.

• Macro assembler code: A few frequently used

routines and subroutines are coded in this assembly

language. All of these routines are base systems or

network communications modules. TIPs do not use

this source code.

Macro Assembler (CLASS) - The CLASS macro assembler is

desihbed m detail in the CYBER Cross System Macro

Assembler Reference Manual. Here, the macro assembler

functions are discussed in terms of the source program and

the output. A few base system and network communications

modules have been written in this language to speed

processing. It is assumed that these programs are invariant.

The macro assembler language allows deﬁnition of macros.

A set of these macros has been predeﬁned for CCP to form

the state programming language. All modules written in

macro assembler language can be found in an assembly

listing.

State programming language: A group of

macroassembler macro commands has been deﬁned

as the state programming language. This

communications-oriented language is used by TIPs

to convert message code/format on the

microprocessing level. Each TIP provides a set of

upline programs (input state programs and in some

cases upline text processing programs) to

demultiplex incoming data and to convert terminal

code/format to IVT or PRU format. Each TIP also

provides a set of programs (called downline text

processing programs) to convert downline data

from PRU or IVT code/format to terminal

code/format.

CLASS Source - A source program consists of one or more

subprograms. Each subprogram is a set of source statements

preceded by a NAM card and followed by an END card.

Each subprogram may be assembled independently, or

several may be assembled as a group. The main subprogram

of a group is the one to which initial control is given; it need

not be the ﬁrst subprogram in the group.

Communication between subprograms is accomplished by

subprogram linkage pseudo-instructions and by the use of

com mon and data storage.

A source statement consists of location, instruction,

address, comment, and sequence ﬁelds, respectively.

60471400 G 1-15

Pseudo instructions control the assembler, provide subpro

gram linkage, control output listing, reserve storage, and

convert data. They may be placed anywhere in a source

language subprogram, but NAM must be the ﬁrst statement

of a subprogram and MON or END must be the last

statement.

A frequently used set of instructions may be grouped

together to form a macro. Once a macro is deﬁned, it may

be used as a pseudo instruction. The CLASS assembler

includes two types of macros:

• Programmer-defined: macros declared and defined

by MAC pseudo instructions; each macro may be

deﬁned anywhere in the program prior to the ﬁrst

reference to it; comment cards may be placed

anywhere in the macro deﬁnition

• Library: definitions contained on the system

library that may be called from any subprogram

CLASS Output - There are two principal CLASS outputs:

• A relocatable binary output: The assembler out

puts relocatable binary format records of variable

length with a maximum of 120 characters from any

peripheral device in the system. The driver for

the input device veriﬁes that the block is read

correctly.

• Listed output: A number of listed output options

are available, including mapping options. The

assembly list output by CLASS consists of descrip

tive information related to the source statement,

followed by a listing of the source statement.

Three types of Cross reference maps can be obtained:

• a complete Cross reference map

• a short Cross reference map

• a macro Cross reference map

Micro Assembler - The micro assembler is described in

detail in the CYBER Cross Micro Assembler Reference

Manual.

The assembler for the microprogram mable processors pro

vides the mnemonic language necessary for the programmer

to write a microprogram. The assembler translates symbolic

source program instructions into object machine instructions

and provides a listing of assembly results. Here, the micro

assembler is discussed in terms of input and output.

• Input: A source input statement to the micro

assembler consists of 11 ﬁelds. Of these ﬁelds, the

location and comment ﬁelds are used to improve

the documentation of the assembled microinstruc

tions, while the eight remaining ﬁelds correspond

to the eight ﬁelds of the microinstruction. Mne

monic instructions allow the programmer to use

convenient names to specify the binary information

to be inserted in each ﬁeld of a macroinstruction.

Pseudo instructions fall into ﬁve classes: assem

bler control, listing control, memory management,

data deﬁnition, and object code output pseudo

instructions.

• Output: The output consists of an assembly listing

including diagnostics if errors occur, a zero loca

tion map, an origin location map, and a relocatable

object image.

CYBER Cross Build Utilities - Four build utitilies are used

to generate a load module for an NPU. This load module is

processed by the NOS installation utilities into a load ﬁle

that is downline-loaded into an NPU to provide its on-line

system. The utilities are:

• An Expand utility defines the characteristics of the

variant that is to be used in a given NPU; that is, it

deﬁnes the memory size of the NPU, the TIPs to be

used, the NPU's identiﬁer to the network, whether

it is a local or remote NPU, the maximum number

of lines that the NPU supports, and identiﬁers for

any trunks that are used.

A second portion of the Expand utility deﬁnes the

variant for the NOS load ﬁle generator.

• An Autolink utility generates the directives that

are used by the Link utility. One of the inputs to

this utility is a ﬁle containing the object code for

CCP programs. This is the code that was produced

by the macroassembler or by the PASCAL

compiler. These object code modules can be

retrieved from a library. During its processing, the

Autolink utility locates CCP programs so that a

maximum amount of memory space is available for

message handling in the on-line system.

• A Link utility generates two files: a memory

image load module ﬁle and a symbol table ﬁle.

Programs in the memory image load module are

placed at the absolute locations where they will

execute. The symbol table provides addresses of

all entry points to these programs. These two ﬁles

are used by the Edit utility.

• An Edit utility allows the user to initialize values

in selected variables and ﬁelds. The output of the

Edit utility is an initialized memory image load

module. This module is presented to the NOS load

ﬁle generator, along with variant information from

the Expand utility. The load ﬁle generator

produces the NPU load ﬁle.

All of these utilities are used in the CCP installation

procedures. See the CYBER Cross Build Utilities

Reference Manual for details of these utilities. The build

procedures themselves are described in the NOS

Installation Handbook.

UPDATE

UPDATE provides a means of maintaining source decks in

conveniently updatable compressed format. The program is

described in the UPDATE Reference Manual.

By using UPDATE, a user initially transfers a collection of

source decks to a ﬁle known as a program library. Each

card of each deck is assigned a unique identiﬁer when it is

placed on the library. This allows each card to be directly

referenced during an UPDATE correction run. During

correction runs, cards are inserted into or deleted from the

program library according to sequence identiﬁcation. How

ever, the image of a card, even though deleted, is

maintained permanently on the program library with its

current status (active or inactive) and a chronological

history of modiﬁcations to the status. If the history lists

the card as being currently inactive, the card has been

deleted and is, in effect, removed from the deck. If the

status of the card is active, the card is in the deck; either it

has never been deleted or has been deleted and restored.

During a single UPDATE correction run, a card may undergo

one or more modiﬁcations or no modiﬁcations.

| 1-16 60471400 G

The UPDATE purge feature can be used to permanently and

irrevocably remove cards from the program library. Once a

purge has been performed on a program library, it cannot be

restored to an earlier level. A set of corrections also has an

identiﬁer associated with it. Any cards affected by the

correction set can be referenced, relative to the correction

set. In later correction runs, all or part of a correction set

can be removed (yanked). Yanking differs from purging in

that it is a logical operation. The effects of a yank can be

reversed.

With UPDATE directives and control card options, the user

directs the process of creating a program library, correcting

it, and copying the updated programs to a compile ﬁle for

subsequent use by assemblers and compilers.

The compile ﬁle is a primary output of an UPDATE run.

This output contains only the active cards of non-common

decks requested by the user.

A second type of output is a new program library. This

contains updated decks requested by the user in program

library format for use as an old program library in

subsequent UPDATE runs. This is a required form of output

during an UPDATE creation run. It may become an old

program library on subsequent correction runs.

A third type of UPDATE output is in the form of an

UPDATE source ﬁle. This ﬁle resembles the decks

originally used to create the program library. It contains

active source cards of the decks and common decks taken

from the updated program library. The source ﬁle provides

a means of obtaining a back-up copy of the library, of

purging all inactive cards, and of resequencing the library.

A source deck can be assigned common status at the time it

is ﬁrst incorporated into a program library ﬁle. Common

decks can be called from within other decks as they are

being written on the compile ﬁle. On the compile ﬁle,

UPDATE replaces the card calling a common deck with a

copy of the deck, provided that the call occurs within a deck

or within a common deck called within a deck.

Source decks can be added to a program library during a

creation UPDATE run or during a correction run provided

that all common source decks precede any source decks in

which they are called.

UPDATE permits two program libraries to be merged. In

this mode, UPDATE alters any deck on the merge ﬁle having

a name that duplicates a name already on the primary

program library by assigning it a deck name that is unique.

255x HARDWARE

The basic product group for the NPU and associated

hardware is:

2551 Network Processing Unit. This consists of a

communications processor with a recommended I

minimum of 96K words of main memory, 2K words |

of micromemory, a maintenance panel, a cyclic

encoder, a multiplex loop interface adapter

(MLIA), and a loop multiplexer (LM).

Optional main memory expansion units (2554-16 for

16K words of added memory or 2554-32 for 32K

words of added memory) are available. Maximum

main memory size is 128K words.

• 2580-4 Autostart System Module is required if the

NPU is used as a remote unit. This uses a tape

cassette.

• At the terminal interface, one or more communica

tions line adapters (256x) are required.

Communications Processor

The communications processor is a microprogrammed 16-bit

processor. Its program instructions are stored in main

memory while the microcode, which dictates how they are

to be executed, is stored in micromemory. This microcode

provides additional power for character and ﬁeld manipula

tion, indexing and other communications-oriented processes.

MAJOR FEATURES

• Microprogrammed and macroprogrammed

• 96K to 128K words of 16-bit (plus parity and |

protect) MOS main memory

Eight memory-addressing modes

Memory word and region protection

Main memory parity detection

High-speed I/O data transfer

Programmable cyclic encoder

STATE PROGRAMMING LANGUAGE

The set of macro assembler macrocommands making up this

language comprises the entire language. No other macro

assembler code is included in state programs.

The language is used for speeding code/format conversion of

data. Standard interface routines between PASCAL-coded

(OPS-level) programs and the state programs are provided.

The state program source code can be found in an assembly

listing for the appropriate TIP. The language and its use are

described in the State Programming Language Reference

Manual.

MACROINSTRUCTION REPERTOIRE

The communications processor incorporates the CDC

CYBER 18 Series instruction set plus extensions. Some

instructions are immediate (literal), resulting in a saving of

operand storage space and execution time. Multiword

instructions, like indirect addressing, are a means of

addressing locations which cannot be accessed directly.

To aid in programming, most CCP programs are written

using PASCAL language rather than macro assembler lan

guage.

0PS

60471400 G 1-17

REGISTERS TAPE CASSETTE

The communications processor emulates a total of 12

registers. Eight registers are used in the execution of the

CYBER 18 instruction set while four general-purpose regis

ters have been added to support the extended instruction

set. There are also three special-purpose registers used

exclusively for machine control.

INPUT/OUTPUT

The communications processor features both a direct mem

ory access (DMA) interface and an internal data channel

(IDC) interface to peripherals. Using the IDC interface, the

program controls the data transfer, employing the Q register

to address the desired peripheral and the A register to

transfer data, commands, or status between- CPU and

peripheral. The IDC transfer rate is 1.6 x 10 bytes per

second. The DMA interface permits direct transfer of data

between the peripherals and main memory, bypassing the

communications processor main registers. The DMA trans

fer rate is 2.8 x 10 bytes per second. Coupler transfers to

the host use the DMA channel.

PROGRAM PROTECTION

The communications processor offers two modes of protec

tion from the damage which may be done by programs

accessing memory outside of their own region:

• Individual words are declared protected by setting

a bit in memory associated with that word.

• Upper and lower bounds to define an unprotected

region. This has the same effect as word protec

tion, except that a large unprotected area can be

deﬁned more quickly. This method is provided by

the 255x software.

INTERRUPT SYSTEM

The interrupt system is implemented through microprogram

and consists of 16 levels of external macrointerrupt, and 16

levels of internal microinterrupt. Macrointerrupts are the

traditional CYBER 18-style interrupts; microinterrupts are

primarily used internally to control the execution of

micromemory instructions associated with the real-time

processing of input/output data.

BREAKPOINT

The breakpoint facility insures the termination of a program

at a predetermined location in memory. Breakpoint is useful

in program debugging. This feature is activated through the

NPU maintenance panel and can be used at either the macro

or microcode level.

AUTOLOAD

The loading of programs is provided by this feature. The

operator can downline-load the NPU from an associated host

computer.

A tape cassette is provided as part of the remote NPU

conﬁgurations. The tape cassette is used as a load device

for auto-start purposes.

NPU MAIN MEMORY

The NPU uses high-speed MOS memory. All memory

conﬁgurations feature the use of 18-bit storage words

comprised of:

• 16 data bits

• 1 parity bit

• 1 program protect bit

Communications processor microcode allows full, direct

access to 65K words of memory. Use of larger memory

(over 65K) is restricted to applications modules, i.e., TIPs,

on-line diagnostics, etc. Features of this large memory use

are:

• virtual memory space of 65 K at any instant in time

• 32-page registers to allow mapping of each 2K page

in virtual memory space to any 2K physical page

• 2 sets of page registers to allow for rapid switching

Multiplex Subsystem

This system utilizes demand-driven multiplexing. Processor

intervention is required only when incoming data characters

are received or when output data blocks require servicing.

The multiplex subsystem components include:

• multiplex loop interface adapter (MLIA)

• loop multiplexer (LM)

• communications line adapters (CLAs)

The ﬁrst two are an integral part of the 255x although the

communications processor treats them as peripheral devices.

The CLAs are peripheral devices attached to the input/

output multiplex loops.

MULTIPLEX LOOP INTERFACE ADAPTER

The multiplex loop interface adapter (MLIA) connects the

communications processor to the loop multiplexers via the

multiplex loop. It initiates and terminates the input and

output multiplex loop requests. It also provides basic

timing and control. The MLIA provides serial-to-parallel

and parallel-to-serial data conversions, loop control and

error monitoring.

LOOP MULTIPLEXER

The loop multiplexer (LM) provides the electrical and

mechanical interface between the multiplex loop and

communications line adapters (CLA) which reside within

the loop multiplexer. Additional loop multiplexers are

available as 2556-11 Loop Multiplexer Line Expansion

Modules. A total of eight loop multiplexers will connect

up to 254 communications lines.

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| 1-18 60471400 G

Communications Console

Two standard types of console may be used for ofﬂine

operations (consoles are not used online):

• 713-10 CRT, variable speeds up to 30 characters

per second

• 752-10 Display Terminal, variable speeds up to

9600 bits per second

Other compatible terminals (such as teletypewriter

devices with similar line speed and I/O characteristics)

can be used.

The 2561 CLA provides for the connection of two

asynchronous communications lines at all standard speeds up

to 9600 bits per second. There is one model: the 2561-1.

The 2561-1 provides for the termination of two lines

conforming to EIA RS-232-C or CCITT V.24 standards. It is

compatible with AT&T 103/113/212 data sets or their |

equivalent. Local connection without a modem is available.

A 2563 series CLA is required for the communications line

connecting local and remote NPUs. This line (trunk) uses

the Control Data Communications Control Procedure

(CDCCP) at speeds up to 20000 bits per second. The line is |

connected via modems (data sets) conforming to the EIA

RS-232-C or CCITT V.24 interface standards.

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2558-3 Channel Coupler

The channel coupler provides a direct link between a host

computer and the communications processor. The primary

function of the coupler is to pass 8-bit data characters

directly between the computer memories with minimum

software supervision. There are four additional control

bits associated with each character. The coupler provides

the means for transfers between a CYBER peripheral

processing unit (PPU) and an NPU at CYBER-channel

transfer rates. Supervision is provided by both PPU and

NPU software commands and by control words in the NPU

buffer. Buffer chaining in NPU memory is provided.

All coupler operations are initiated by PPU function

commands and/or NPU I/O commands. The transfer of

data between computers requires additional PPU I/O

instructions and control words in NPU memory.

Communications Line Adapters

The 256x series of communications line adapters (CLAs)

are used to interface the NPU to various types of

terminals or communications facilities. The CLA provides

the electrical interface, isolation, control, and interim

character buffering.

There are three classes of 256x CLAs:

• 2560 Series Synchronous Communications Line

Adapters

• 2561 Series Asynchronous Communications Line

Adapters

• 2563 Series CDCCP Communications Line Adapt

ers (used with remote NPUs)

Sample Conﬁgurations

Figure 1-8 shows a typical conﬁguration for a local 2551-1.

The 2551-1 is intended as a local NPU or a remote NPU. In

the remote format the coupler is absent and a trunk-

connection links the local and remote NPUs. The unit is

limited to a maximum of 32 input lines.

The 2551-2 is intended as a local NPU or a remote NPU. In

the remote format, the coupler is absent and a trunk

connection links the local and remote NPUs. This unit can

connect up to 254 communications lines.

Terminals Supported

The NPU/terminal interface is supported by one of several

standard terminal interface programs: the asynchronous

TIP, the Mode 4 (synchronous) TIP, the BSC TIP, the HASP

(synchronous) TIP, and the X.25 TIP. The classes of

terminals typically supported by each of these types are as

follows:

Mode 4 TIP

CDC 200 User Terminal

Card readers

Line printers

Tektronix Synchronous 4014

CDC 714-30 User Terminal

711

714

CDC 734 Terminal

Terminal code may be ASCII, EBCDIC, external

BCD, or correspondence code. Terminals may use

Mode 4A or 4C protocol.

Terminal

Class

2560 Series Synchronous Communications Line Adapter

The 2560 series CLA provides for the connection of two

synchronous communications lines.

A 2560 series CLA provides for the connection via modems

(data sets) of lines conforming to the EIA RS-232-C or

CCITT V.24 interface standard. The CLA is compatible

with AT&T 201/208 data sets and provides for the

termination of two communications lines.

Terminal

X.25 and Asynchronous TIP Class

T T Y M 3 3 , 3 5 , 3 7 , 3 8 1

C D C 7 1 3 2

IBM 2741 (asynchronous only) 4

T T Y M 4 0 5

Hazeltine 2000 6

C D C 7 5 1 7

Te kt ro ni x A sy nc h r o n o us 40 1 4 8

All X.25 terminals use ASCII code only.

60471400 G 1-19

HASP TIP

Data 100

Harris COPE 1200

Harris 1620

Terminal

Class

9/14

BSC TIP

IBM 2780

IBM 3780

Terminal

Class

Terminal class 9 consists of HASP postprint

devices; terminal class 14 consists of HASP

preprint devices.

2551-1 CONFIGURATION

HOST l~2558-3 "~l

COMPUTER ~tJ ™A™EJ- I

(2) . COUPLER

COMMUNICATIONS

PROCESSOR

MAINTENANCE

PANEL

48K WORDS

MEMORY

CYCLIC

ENCODER

MULTIPLEX LOOP

INTERFACE

ADAPTER (MLIA)

MEMORY EXPANSION

2554-16, 32

I 1

J 16 OR 32K I

• MEMORY ■

I I

EXPANDABLE TO 128K WORDS

OF TOTAL MEMORY

1 TO 32 COMMUNICATIONS LINES

(MAXIMUM: 2 LINES PER CLA;

MODEMS MAY BE USED TO

CONDITION LINES)

NOTES:

REQUIRED

OPTIONAL

(1) CLAs AND MODEMS SELECTED AS REQUIRED. ONE OR TWO

COMMUNICATIONS LINES CAN BE ATTACHED TO A CLA DEPENDING

ON LINE TYPE. A MAXIMUM OF 16 CLAs ARE ALLOWED IN THIS

CONFIGURATION.

(2) IF USED AS A REMOTE NPU, THE CHANNEL COUPLER IS NOT USED;

HOWEVER. A 2580-4 SYSTEM AUTOSTART MODULE IS REQUIRED.

Figure 1-8. Sample NPU/Peripheral Hardware Conﬁgurations

1-20 60471400 G

OVERVIEW OF CCP FUNCTIONS

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The NPU, operating under control of CCP, provides multi

plexing of terminal data for the host. The necessity, for

multiplexing has been explained in section 1, under the

heading of multiplexing operation.

MULTIPLEXING, SWITCHING, AND

DATA CONVERSION

On input (upline) transfers, the data from the various

terminals (or remote NPUs) is multiplexed, placed into PRU

format or interactive virtual terminal (IVT) format,

demultiplexed and gathered into message-sized buffers, and

passed to the host. On output (downline) transfer, the

messages from the host are translated into real terminal

format, if necessary, and are then multiplexed to the

terminals, one character at a time.

There are some exceptions to this scheme. If a remote NPU

is in the system, the conversion from terminal to PRU or

IVT format occurs in the remote NPU. Data is passed

between the remote and local NPUs in frame format. It is

then reconstituted in the receiving NPU where processing

continues as if the data had just come from the host

(downline), or from the TIP (upline).

The two major interfaces are buffered. On the host side,

upline, full messages are placed in one or more (chained)

buffers, the host is alerted that the message is ready, and

the transfer takes place over the direct memory access

(DMA) channel connecting the peripheral processing unit

(PPU) of the host to the NPU. There is, of course, some

communication between the host and the NPU to ready the

transfer. The PPU receives the message in buffers.

Message includes data messages, certain types of blocks

that are used to transmit control information, and service

messages that carry control and status information. When

the message is reconstituted in the host, and conﬁrmed as

being good data, the PPU passes the buffered data to the

applications program (see ﬁgure 2-1).

The downline transfer at the host interface is the converse

of the operation described above. When the PPU has the

complete message in a buffer, it notiﬁes the NPU. If the

NPU has sufﬁcient buffers to start another message, it

assigns a data buffer and accepts a block or blocks of

information, assigning successive chained buffers as needed

until the entire message is reconstituted in NPU main

memory. If the data is conﬁrmed as being good, the

message is passed to the next stage of processing, which is

transformation to terminal format. This is accomplished by

a combination of TIP and BIP conversion processes.

Buffering also occurs at the terminal interface. All

terminals are connected to the input and output multiplex

loops via CLAs and communications lines. For an upline

message, the tagged data characters are picked from the

input multiplex loop, and passed to a circular input buffer

along with tagged data from all other active terminals. It is

then demultiplexed into one or more data buffers. When the

message is completely assembled, the TIP and the BIP

transform the data as necessary. In many cases, this is a

one-pass process. However, the HASP TIP requires two

stages of demultiplexing. The end product is a buffered

message ready to be passed through the host interface to

the applications program in the host.

NOTE

In this highly generalized discussion, it is assumed

that all messages are being passed through the NPU

from host to terminal or conversely. However,

many control messages originate or terminate in

the NPU itself.

HOST/PPU

BUFFERED

MESSAGE

APPLICATION

PROGRAM

BUFFERED

MESSAGE

NPU

BUFFERED

MESSAGE

OUTPUT

CONVERSION

AND

PROCESSING

MUX

SUB

SYSTEM

BUFFERED

MESSAGE

CIRCULAR

INPUT

BUFFER

INPUT

CLA

TERMINAL

THROUGHPUT

CONTROL

Figure 2-1. Simpliﬁed NPU Buffered Transfers

60471400 G 2-1

Any buffering at the terminal is invisible to the NPU. The

NPU need only assume that the line to the terminal can

input or output data at the minimum rate for that line. If

this does not occur, the line is noted to be bad and the

associated terminal is marked down. The entire message

associated with the line failure is rejected.

Downline transfers at the terminal interface are handled

differently for batch and interactive devices.

In the case of ASYNC IVT blocks, the BIP passes data to the

TIP which converts the data, queues it, and passes it to the

multiplex subsystem.

In the case of PRU blocks, the BIP passes data to the TIP

which converts it to one or more transmission blocks (a

transmission block carries a printer line or a card image)

and then passes the transmission blocks back to the BIP.

The BIP then queues these blocks to the TIP unless there is

some reason to interrupt the batch output process. If there

is such a reason, the BIP refrains from passing the

transmission blocks on to the TIP as the TIP requests them.

This makes it possible to send interactive messages to the

terminal. When the batch interrupt is cleared, the BIP again

starts passing transmission blocks, which the TIP then passes

to the multiplex subsystem.

The multiplex subsystem picks the message, one character

at a time, from the transmission block, tags it, and places it

on the output loop. The CLA for the line is responsible for

recognizing its own tagged data, passing it to the receiving

terminal, and requesting more data. This process continues

until the entire transmission block is sent.

Buffer space management is an important task for the NPU.

Release of buffers is handled according to the criteria shown

in table 2-1.

The upline switching operation performed by the local NPU

is relatively simple in this release since each local NPU is

connected to only one host. For this release, the NPU acts

as a message gatherer. If the host should fail, the local NPU

is responsible for delivering a message to the terminal

indicating that the host is unavailable. When the host is

reactivated, another message is sent to the terminals

notifying them that the system is again operational. For

remote NPUs, although potentially usable links may exist to

two local NPUs, only one link is used at a time. If that link

should fail, the link to the alternate local NPU is activated.

From the viewpoint of the remote NPU, all trafﬁc is

channeled to the local NPU, though the identity of that NPU

may change from time to time.

For downline switching, the local NPU is responsible for

checking the operational status of the terminal or remote

NPU. The remote NPU is responsible for checking the

status of the terminals directly attached to it. There is no

option to deliver a rejected message to an alternate

terminal. However, since the host applications program

which originated the message is informed of the failure to

communicate, it is possible for that program to route the

message to an alternate terminal.

Regulation of input to an NPU may cause a unit attempting

to input to the NPU to have its message rejected. That unit

(host or terminal) is responsible for inputting the rejected

message at a later time.

Data conversion is provided for the convenience of the host

application programs. These programs expect data in one of

two formats: IVT in ASCII code or PRU in display code.

Transparent data is also allowed. For batch transmissions,

data compression is allowed if the protocol supports it. In

most protocols batch input cards have trailing blanks

truncated and some zero ﬁll following the last data

character.

/ < ^ S

TABLE 2-1. BUFFER ASSIGNMENT/RELEASE IN NPU

Transfer

Direction

Upline

Downline

Upline

Downline

Interface

Host

Terminal'

Terminal

Assign

Receives buffers from NPU's BIP via

TIP or LIP.

Can postpone assignment based on

lack of buffers; otherwise assign

and chain as data is received.

Same as host/downline, plus buffers

may not be assigned if a connection

has already reached its buffer

limit.

Same as host/upline,

Release

When coupler acknowledges that message

block was correctly received, or when error

occurs.

Messages: when next stage of NPU proces

sing converts message to new format or when

error occurs. Control messages or blocks:

when NPU ﬁnishes action speciﬁed or when

message is garbled.

Same as host/downline.

When terminal acknowledges that last block

was correctly received or when message can

not be transmitted after several attempts

(host application program is notiﬁed in

l a t t e r c a se) .

TThese are demultiplexed buffer blocks, after reconstituting data from the circular input buffer (CIB),

space is never released. CIB

/«^K

2-2 60471400 G

j g ^ S

INTERFACES

Two interfaces have already been discussed in this section,

the host interface and the terminal interface. There is also

one other interface, the local/remote NPU interface.

Each interface has its own protocol or sets of protocols. It

is the NPU's task to convert data from the appropriate input

protocol to the appropriate output protocol. Table 2-2

summarizes the protocols and primary packets of data used

for the protocol. The data packets, blocks, frames and

special types of messages, are discussed in more detail later

in this section.

TRANSMISSION MEDIA

The basic transmission medium for data within the NPU is

the block. This holds true absolutely at the host interface

and can be considered a constant also at the other

interfaces since any amount of data, even one character,

is collected into a data buffer, in block form, and held

until the NPU delivers the entire message, aborts the

message because the channel is inoperative, or acts on the

data if the data is in fact a command or a request for

information. At the terminal interfaces, however, the

blocks may be reformatted into frames (trunk transfers).

In the following discussion, the handshaking operation to set

up a channel or line for operation is neglected. The

handshaking techniques are discussed in detail later in the

HIP, LIP and base software sections with respect to the

host, to the NPU at the other end of a local/remote NPU

link, and peripheral devices, respectively.

There are 12 block types. They can be divided into three

catagories:

• Data transfer blocks (MSG and BLK): For

interactive devices, BLK blocks convey any part of

the message but the end. MSG blocks convey all

the message or the end of the message. A typical

large interactive message requires several chained

BLK blocks with a MSG block at the end of the

chain. For batch devices, a PRU block always uses

a MSG block. A single batch job may require

several PRU blocks. All but the last PRU block

will be full. In the last or only PRU block, an end

signal (end of text, end of input, or other end

signal) signiﬁes the end of the logical chain of data.

• Control blocks: BACK blocks acknowledge receipt

of other blocks; BRK, STP, STRT, RST, INIT,

ICMD, and ICMDR are used to break, stop, start,

reset, initiate, and interrupt the ﬂow of data

blocks. CMD blocks transfer commands to

conﬁgure the network and to regulate the ﬂow of

data blocks. CMD blocks are also used to transfer

network status information.

• Data assurance blocks (inter-NPU only): ACTL

blocks are used to set up, monitor, and maintain

continuity on the trunk connecting two NPUs.

ACTL blocks appear in frames as will be apparent

in the frame discussion that follows

The range of commands available in a CMD block is

potentially very large. However, to establish a useful

protocol, a set of commands called service messages has

been deﬁned. These messages perform the same sort of

function for the NPU that supervisory messages perform in

the host, transmitting commands and status.

TABLE 2-2. INTERFACE/PROTOCOL RELATIONSHIPS

Interface Protocol Data Packet/Responsible Modules I/O Channel Code Sett

Host Bl ock Data block made out of (chained) Direct Memory ASCII in IVT; display

buffe rs. "Ha nds hak ing " tec h Access (DMA) code or ASCII in PRU

nique at coupler to set up the (high speed) mode.

transfer. HIP and BIP handle

transfers.

Terminal Any Acceptable At NPU side, blocks chained in Mux Inter Usual are ASCII and

such as Mode data buffers. Wide range of fac e, Inp u t some form of BCD; may

4, BSC, ASYNC, trans fer rates. TIP and BIP or Output use APL variations or

HASP, X.25 handle conversion. Loop correspondence code.

with PAD sub

TIP

Remote/local Form of ISO Data blocks formed into frames Mux Inter Code is transparent

NPU HDLC called and chain ed togethe r. Transfer f ace , I npu t to the LIP.

CDCCP rate up to 19200 bps. LIP

handles frame formation and

breakup. LIP at either end of

line; functions complementary

and depending on transfer

direction.

or Output

Loop

'Some transfer8 can also be in transparent format.

60471400 G 2-3

Comparable service and supervisory messages exist; some of

these are, in essence, transforms of one another. In the

host, the NAM, NS, and CS modules receive, generate, and

process service messages. In the NPU, most service

message processing is handled by a service module (SVM).

Service messages ordinarily do not go through the NPU as

such, although they may be transmitted intact over a trunk

(remote NPU/host messages), or they may carry with them a

character data message to be displayed at a terminal or at a

console (network operator (NOP), local operator (LOP)).

Service messages are summarized in the System

Programmer's Reference Manual.

A typical incoming service message solicits a response and

causes the NPU to generate an appropriate response service

message. Examples of this would be a conﬁguration

message, answered by a response that the device speciﬁed

has been conﬁgured as requested, or a status request

answered by a message carrying the requested status. In

some cases, the NPU generates a so-called unsolicited

response message. This somewhat confusing terminology

indicates that the NPU has used the normal response form of

a service message to generate a warning that the system is

not operating as conﬁgured. An example is the unsolicited

line status request response. That is, in fact, a report that

the line speciﬁed in the message has been marked down, and

further attempts to output messages to the terminal using

this line will be rejected. The host must therefore take

action to have the line repaired or reconﬁgured.

Although blocks retain some of the basic transmission

format when sent over trunks connecting local and remote

NPUs, a new unit of transmission called a frame is also

deﬁned. As in the case of blocks, there are different

categories of frames:

• Command frames: Two types are defined, S

(supervisory) frames and U (unnumbered) frames

monitor channel communications.

• Data frames: I (information) frames transmit data.

Data is placed in the frame in units of subblocks. A

subblock may be a full block or only a portion of a block.

Normal frame size for CCP (an installation-time parameter)

is 259 bytes (8 bit characters).

An example may clarify this: Suppose three messages are

waiting to be sent upline from a remote NPU. The lengths

are 32 bytes, 256 bytes, and 32 bytes, and are queued in that

order. The 256-byte message is contained in two 128-byte

data buffers. The ﬁrst 32-byte message and the ﬁrst buffer

of the 256-byte message require together: 32 + 128 + 2

(frame overhead) + 2x2 (two bytes of frame overhead per

subblock) = 166 bytes. The next subblock is 128 (+2) bytes.

166 + 130 > 259 so the frame is closed and transmitted with

166 bytes. The next frame will contain the second half of

the 256-byte message and the other 32-byte message. Since

no other messages are waiting to be transmitted, this frame

is also closed and sent.

NOTE

This simpliﬁed example ignores such factors as

checking frames on the receiving side, acknowledg

ing them, and requiring retransmission of all

frames since the last acknowledged good frame in

the event that a frame transmission fails.

As soon as the frame is stripped off in the receiving NPU,

the various messages are reassembled into data blocks and

all traces of frames disappear.

INITIALIZATION

Since the terminals connected through the NPU must be

conﬁgured to match the host's image of the network

conﬁguration, and since the NPU has no mass memory, the

NPU image is kept on host mass storage and the NPU is

downline-loaded from the host. After the baseline system is

loaded, the host directs the NPU to conﬁgure its links, lines,

and terminals by means of a series of service messages. The

three steps of the initialization are:

• (optional) dump the NPU so that contents can be

used for later analysis to determine cause of

failure

• load the NPU from the host with the baseline

program

• configure the NPU by establishing the parameters

of the logical links, lines and terminals connected

to this NPU

Differences in the initialization cycle result from hardware

differences. The two formats required are for:

• 2551 local NPUs

• 2551 remote NPUs

The host normally attempts to load/dump an NPU only if

the NPU fails or if the network operator speciﬁcally

requests a load. If the host itself fails, the NPU must also

be reloaded when the host comes back on-line. In the case

of an NPU failure, the host (optionally) ﬁrst dumps the

NPU contents. The NPU is then loaded. If the ﬁrst

attempt to load the NPU fails, another dump is taken. On

subsequent consecutive attempts to load, dumping is inhib

ited. After a set number of times, the NPU is marked

down. Failure of a local NPU is detected by the host PPU

channel.

NPUs that are local to the host are loaded and dumped via

the CYBER Coupler under the control of the PPU. The

remote NPU requires an overlay process in the local NPU.

When a remote NPU fails, the deadman timer is activated.

A bootstrap load/dump program is read into the NPU from

the system autostart module cassette, and that bootstrap

program starts execution. The remote NPU then establishes

contact with the local NPU. The local NPU communicates

with the remote NPU using a restricted set of the

communications protocol during this load/dump procedure.

From this point forward, the load/dump procedure is

controlled by the host, using an overlay in the local NPU.

After the NPU is loaded, the host conﬁgures the unit by

establishing all logical links and logical connections for that

NPU. A logical connection is the association of two

elements made by the assignment of a network logical

address. The network logical address is a set of three

numbers: two node IDs followed by a connection number.

These three numbers are used together to trace through a

set of increasingly speciﬁc directories: the destination node

directory, the source node directory, and the connection

directory. This process ultimately points to a terminal

control block (TCB). The directories also have information

concerning the logical link control block (LLCB), the line

control block (LCB), and the logical channel control block

(LCCB). It is these three control blocks that are the subject

of the NPU conﬁguration process.

y^BSv

2-4 60471400 G

The network supervisor (NS) program and the communica

tions supervisor (CS) program in the host are responsible for

the control of logical links and connections, respectively, in

the network. All logical links and connections are explicitly

conﬁgured, reconﬁgured and deleted by NS/CS using service

messages (SM). Conﬁguration proceeds in three stages:

• establishing logical links

• configuring lines

• connecting terminal over the lines

NS establishes all logical links which the current state of the

network permits. NS notiﬁes CS of each logical link to be

established and the initial regulation level for the logical

link. CS conﬁgures the lines and attempts to connect each

terminal on the line.

To connect the terminal, the line must be enabled. The

terminal is connected by the NPU building the terminal

control block (TCB) for the terminal. When the conﬁgure or

reconﬁgure action has been performed, the block protocol is

initiated and the connection is in use.

BASE SYSTEM SOFTWARE

The base system software consists of most of those portions

of the CCP that are normally associated with a

comprehensive operating system together with the

associated standard utilities. The base system, plus the

block interface package (BIP), and the other interface

packages (HIP, UP, and all TIPs) constitute the standard

CCP software. Initialization and conﬁguration was

ibed previously. The major features of the base systemdesc

are:

system monitor

buffer handling

worklist services

queuing mechanisms

direct program calls (switching services)

interrupt handling

timing services

globals

control block services

directory maintenance

standard subroutines for code translation, and

special arithmetic functions

multiplex subsystem operation

SYSTEM MONITOR

The NPU is a multiple interrupt level processor. Interrupts

are serviced in a priority scheme in which all lower priority

interrupts are disabled during execution of a program

operating at a higher priority level. When no interrupt is in

effect, the processor runs at its lowest priority, known as

the operations monitor (OPS) level. Programs on the OPS

level communicate with one another using worklists. Para

meters for the requested task are stored in a worklist and

the worklist is placed in a ﬁrst-in/ﬁrst-out queue for the

program to be called. The monitor scans the list of all

programs capable of having worklist queues. If the monitor

scan discovers a program with one or more worklists in its

queue, control is passed to the program, together with the

worklist which deﬁnes the parameters for the task. It is

possible to pass control to a program for execution of more

than one worklist, if that program is designated as being

allowed to process more than one task before releasing

control. In this case, the maximum number of queued tasks

(worklists) are executed by the program before the program

returns control to the monitor. When the task or tasks are

completed, control returns to the monitor which resumes the

scan at the next program on the list.

Each time a program completes, a timer is advanced. This

timer is checked by the interrupt level timer routine at

speciﬁc system-deﬁned intervals. If the timer expires, it

indicates that some OPS-level program has been abnormally

delayed. Monitor execution is then terminated and the NPU

is stopped.

BUFFER HANDLING

The buffer handler allocates the four types of buffers and

recovers buffers for the four free buffer pools when users

are ﬁnished with them. Buffers are potentially available in

six sizes: 4, 8, 16, 32, 64, and 128 words. At installation

time, the user chooses any four contiguous sizes; for

instance, 8, 16, 32, and 64 words. The largest size is

designated as the data buffer size.

Buffers are assigned one at a time; buffers can be released

singly or in a chain of buffers.

In conjunction with testing buffer availability to assure a

minimum threshold number, buffer maintenance periodically

attempts to adjust distribution of buffer sizes by using

buffer mating or buffer splitting to replenish any buffer pool

that is at threshold level.

WORKLIST SERVICES

Worklists provide a convenient method of handling communi

cations between software modules that do not use direct

calls. The list services function manipulates worklists by

making worklist entries from any priority level (including

OPS level).

Characteristics of the queued worklists are:

• first in, first out

• one to six-word entries, but all entries in any one

list of equal length

• lists exist in dynamically assigned space

• No limit in the number of lists serviced

If there is contention between priority interrupt levels when

making an entry, this conﬂict is resolved by use of an

intermediate worklist array.

60471400 G 2-5

QUEUING MECHANISMS

I Several major queues are deﬁned:

• terminal control block (TCB) queue which controls

input messages from the various terminals

I* TCB output queues which control messages to be

passed downline to the terminal

• timing queue

DIRECT PROGRAM CALLS (Switching Services)

Most OPS-level programs call other programs and subpro

grams directly. One subroutine is provided for these direct

calls. The same program also is the ﬁnal step in the

worklist calling sequence. It provides switching for pro

grams on different main memory pages, timed and periodic

calls, service message switching, and overlay execution, as

well as actual passing of control for programs called by the

monitor.

The input data processor (IDP) services the inter

rupt produced when the MLIA places a data

character or CLA status into the circular input

buffer. The IDP (part of the multiplex subsystem)

uses the designated input state program to process

the character according to the requirements of the

protocol and to transfer the characters to the line-

oriented input buffer.

The timing services ﬁrmware processes the 3.3-

millisecond clock interrupt which is used for the

time base of all timed NPU functions.

TIMING SERVICES

Timing services provide the means for running those

programs or functions which must be executed periodically

or following a speciﬁc lapse of time. These timing services

are available:

• A firmware program handles the 3.3-millisecond

microinterrupt to provide a 100-millisecond timing

interval.

/^^t\

INTERRUPT HANDLING

The NPU can recognize 16 different macrointerrupts. Each

has its own address to which control is transferred when the

interrupt is acknowledged. When the computer is processing

a particular interrupt, it is deﬁned as being in the interrupt

state (state 00 through 15). However, before the computer

can recognize an interrupt, the corresponding mask bit in

the interrupt mask register must be set and the interrupt

system must be activated.

Upon recognizing an interrupt, the hardware stores the

appropriate program return address to ensure that the

software can return to the interrupted program after

interrupt processing.

The interrupt handler that is activated also saves selected

NPU registers for the interrupted program. The interrupt

mask is then loaded with a mask to be used while in this

interrupt state. The program then saves the current

software priority level, sets the new software level, acti

vates the interrupt system, and processes the interrupt.

During interrupt processing, an interrupt request with a

higher priority may interrupt this program. Such higher

level interrupts also store return address links and registers

to permit sequential interrupt processing according to

priority level with eventual return to the main-stream

computer program.

The computer exits from an interrupt state when processing

is completed. The handler inhibits interrupts, restores the

registers, and retrieves the return address of the interrupted

program. Control is transferred to the return address and

the interrupt system is again activated.

Three microinterrupts are also serviced:

• The output data processor (ODP) services the

output data demand (ODD) interrupt which each

CLA generates to indicate that it is ready to

output another character. The ODP (part of the

multiplex subsystem) gets the next character from

the appropriate line-oriented output buffer and

puts the character on the output loop. The

requesting CLA picks the character from the loop

and transmits it.

• Every 100 milliseconds, a timing routine searches a x-«sv

chai n o f t i me-lap se entrie s . If any entry ' s time ■

period has elapsed, that entry is deleted from the

chain and a worklist entry is sent to the program

for which the delayed call was requested. Timing

services also handle adding delay requests to this

delay request chain.

• Every 500 milliseconds, a timing routine checks the

deadman timer. The timer is reset and the monitor

timeout routine is checked. If the monitor timer

has expired, it indicates that the monitor has spent

too long in one OPS-level program. The NPU is

stopped. /^«k

• Every 100 milliseconds, a timing routine scans the

list of active line control blocks (LCBs) for ASYNC I

TIP terminals. If a character has been received, |

the timeout is reset for the next character. If the

character has timed out (no character received

within 100 milliseconds), the LCB is removed from

the active list and the ASYNC TIP is notiﬁed.

• A 500-millisecond program time has these principal

functions:

Every second, a timing routine checks all 1

active outputting lines to see if an output data

demand (ODD) has been generated for the next

character to output. If a second has expired

with no new ODD interrupt, the multiplex

event worklist processor is called to declare a

hardware failure for the line.

Every 500 milliseconds, a timing routine scans

all active lines for periodic requests. If the

period has elapsed, the TIP is called using a

worklist. Input or output can be terminated

for the line if this is requested. Inactive LCBs

are unchained from the set of active LCBs.

Timer services also provide the means of

chaining LCBs to this list of LCBs requiring

periodic action. 3

A time-of-day routine is called every second.

The time of day is incremented and, if

necessary, recycled to start of day (00 hour, 00

minute, 00 second). <*s^

2-6 60471400 G

GLOBALS controls modems and analyzes status

PASCAL-coded programs can use global variables, tables,

and constants. PASCAL globals are deﬁned in the CYBER

Cross PASCAL Compiler Reference Manual. The principal

globals used by standard CCP programs are described in the

CCP System Programmer's Reference Manual.

CONTROL BLOCK SERVICES

The line control blocks (LCBs) are a vital part of the

conﬁguration data. The blocks consist of a series of entries,

one for each line. LCBs are chained together and are

therefore handled as a series of active, chained blocks.

Entries that are no longer active are ﬂagged. If an entire

block has no active entries, the block is unchained and

released. New blocks are added as needed. The LCB space,

however, is dedicated and cannot be used for other purposes.

DIRECTORY MAINTENANCE

This set of modules sets up and maintains the directories

which are used for block routing.

STANDARD SUBROUTINES

This group of subroutines provides handling to:

convert and handle numbers

handle interrupt masks

maintain paging registers

save/restore registers

set/clear protect bits

code conversions

perform miscellaneous other tasks

MULTIPLEX SUBSYSTEM OPERATION

The multiplex subsystem has two principal tasks:

• relieve the TIPs of having to process lines accord

ing the the physical line characteristics (most line

characteristics are invisible to the TIPs as a result

of multiplex subsystem processing)

• multiplex the data to match the low-speed charac

teristics of individual terminals with the high-speed

characteristics of the NPU and the host

The principal multiplex subsystem functions are:

• receives serial data from communications lines,

places it in a circular input buffer, demultiplexes it

and places it into line-oriented input buffers

• transmits serial data to communications lines from

line-oriented output buffers

• detects and processes special characters

• translates code on input

• checks CRC

• checks and generates character parity

• detects breaks

• assembles input data into blocks

• chains data buffers as necessary to create data

blocks

• processes commands issued by the communications

system software

• dynamically alters the input character processing

characteristics as a function of the connected

terminal

Figure 2-2 shows the basic multiplex subsystem elements.

Input Multiplexing

Each line has a communications line adapter (CLA). The

CLA for each active line is sampled in sequence and if a

character is ready, it is placed on the input multiplexer loop

together with information identifying the source (line) and,

in some cases, the nature of the character (for instance, this

type may contain control information rather than a charac

ter of message data). All information on the input multiplex

loop is routed to a circular input buffer (CIB) which is

usually 512 words long. The demultiplexing operation picks

data from this buffer and reconstitutes the messages on a

line input basis.

Output Multiplexing

When the NPU has received a message block from the host

and a TIP has transformed the code/format from IVT or

PRU to terminal format, the TIP notiﬁes the multiplex

subsystem that the transmission block is ready for output.

The multiplex subsystem picks the characters from the line's

output message buffer one at a time, whenever a new output

data demand (ODD) is generated by the CLA. (The ODD

indicates the terminal is ready to receive another

character.) The outgoing characters are placed on the

output multiplex loop, along with such control characters as

are needed, and an address that will be recognized by the

active line for that terminal. The CLA for the line

recognizes the address, picks that data from the output

loop, and marks it as being sent. When the contents of the

entire output buffer for the line have been transmitted, and

the message has been acknowledged as received by the

terminal, the multiplex subsystem notiﬁes the TIP. The TIP

releases the message buffers and notiﬁes the host of a

successful transmission. In some cases the TIP discards the

output message even if it was not successfully transmitted.

Trunk Multiplexing

If a remote NPU is included in the network, transmissions

between the local NPU (see previous subsection on 255x

hardware) and the remote NPU take place over a trunk. In

the local NPU, a link interface package (LIP) sets up the

output buffer, and the message in that buffer remains in IVT

or PRU format while being transmitted over the

trunk. In the remote NPU, the downline messages are

treated similarly to upline messages in a local NPU; that is,

the message goes through the CIB and is then demultiplexed

by the LIP for the TIP. After the TIP translates the code

from virtual terminal format to terminal format, the

message is treated as an output message in a local NPU;

that is, the message is multiplexed for transmission, is sent,

and is acknowledged. The acknowledgment must be for

matted then as any other input message: remultiplexed, and

sent upline through the local NPU to the host.

^ms

60471400 G 2-7

INPUT LOOP

COMMUNICATIONS PROCESSOR

MULTIPLEX

SUBSYSTEM

MICROPRO

GRAMS AND

SOFTWARE

INCLUDES COMMAND

DRIVER, INPUT DATA

PROCESSOR, AND

OUTPUT DATA

PROCESSOR

MEMORY BUFFERS

<0L OUTPUT LOOP

MULTIPLEX

LOOP

INTERFACE

ADAPTER

(MLIA)

tt v

LOOP

MULTI

PLEXER

MULTIPLEX

LOOPS

nQiA4-*l

V |

V y l

( CLA W4—▶

COMMUNI

CATIONS

LINES OR

TRUNKS

LOOP

MULTI

PLEXER

■MULTIPLEX SUBSYSTEM-

CLA - COMMUNICATIONS LINE ADAPTER

TIP - TERMINAL INTERFACE PROGRAM

LIP - LINK INTERFACE PROGRAM

r^ms.

Figure 2-2. Basic Elements of the Multiplex Subsystem ^3iS3K

Input messages (upline trafﬁc) are reformatted from

terminal to PRU or IVT format as in a local NPU, but are

then sent by the LIP through the remote NPU multiplexer,

received by the local NPU multiplexer, and reconstructed

into complete messages in the local NPU by that NPU's

LIP. It is apparent then, that through messages (non-control

messages) are multiplexed twice in a remote NPU, once

to/from the terminal and again from/to the local NPU.

Demultiplexing

For one-pass TIPs, the multiplex subsystem is responsible for

picking data out of the CIB as well as for putting it into a

line-oriented input buffer. When a message transmission

starts, the multiplex subsystem reserves a data buffer for

the message (data buffers are normally 64 words long, with 2

characters per word). The words in the CIB are identiﬁed by

the line number, and are packed into a line-oriented input

buffer. If a buffer is ﬁlled before the message is complete,

another buffer is assigned and is chained to the ﬁrst.

When the end of text (ETX or the equivalent) is detected,

the TIP appropriate for the terminal type is called. It

continues the processing by passing the message to the

host interface package (HIP). The HIP will then pass the

message through the coupler to the PPU of the host.

The demultiplexing of downline transfers is a terminal

function; that is, the message is reconstituted in a buffer

for the screen, printer, magnetic tape, etc.

BLOCK INTERFACE PACKAGE (BIP)

This CCP software handles network communications. The

major BIP functions are:

• Routing (switching) blocks for the CCP.

• Providing routines to handle the block protocol on

the host interface side of the TIPs. Bad blocks

are discarded and good blocks are acknowledged.

The host senses that a downline block has been

discarded by failure to receive an

acknowledgment. The terminal is notiﬁed with a

message when a downline block is discarded due

to no connection. Some PRU and IVT formatting

is also done.

• Handling failure and recovery, loading and

dumping, and regulating input to the NPU.

• Providing system diagnostics. Routines send

alarm messages to the network operator, and

generate CE alarm messages and statistics for the

host engineering ﬁle. Also, if the NPU stops, the

diagnostics provide a reason code and other

information concerning the stop.

• Handling the service messages which configure

the network.

2-8 60471400 G

BLOCK ROUTING ROUTING

A major portion of this processing provides block switching

so that the data block can ultimately be routed downline to

the proper terminal or upline to the host.

Data traveling in either direction is tagged by the

terminal ID. A group of directories are provided which

assures that the block control information (contained in a

header) is decoded. The block is attached, through control

blocks for that line/trunk and terminal, to the next

program that must process the block.

SERVICE MODULE

The block format itself allows only a limited set of

commands. Most of the large number of speciﬁc

commands transmitted throughout the system are handled

by the special type of command block called a service

message. These messages are handled by the service

module. There is a large variety of service messages (one

type for each command, with a related normal response

and a related error response):

• Configuring logical links, trunks, lines, and

terminals, as well as the basic load/dump NPU

service messages, are described in the initiali

zation section (section 3). These messages

originate in the NS or CS modules of the host for

normal conﬁguration and reconﬁguration. Mal

functioning of a line or any component of the line

may generate an upline service message indicating

that the line or component is no longer usable. NS

or CS will then reconﬁgure the network accord

ingly.

• Service messages regarding failure and recovery,

and those that support diagnostics are discussed in

section 4 (failure, recovery and diagnostics).

• The remaining service messages provide com

mands for such things as status, broadcasting a

message to a terminal, or sending a message from

a terminal to the network operator's (NOP) or

local operator's (LOP) terminal.

INTERACTIVE VIRTUAL TERMINAL COMMANDS

Interactive virtual terminals are capable of changing some

of their operating characteristics such as page width, page

length, the character to be used for breaks, backspacing,

aborts and other terminal features. These command

messages can originate from the host or from the

terminal The BIP supplies routines to validate the

commands and to start implementation of the commands.

BATCH TERMINAL PRU COMMANDS

Batch device operating characteristics can also be

changed. There are two types of changes: those which

change device characteristics (page width or length, PRU

block length, and sub device type) and those which change

ﬁle characteristics (ﬁle type, ﬁle limit, carriage control,

punch and lace card control). Both types are sent downline

from the host; the code type (026/029 punch) and

transparent/non-transparent mode can also be changed by

BSC/HASP batch devices. The BIP supplies routines to

validate the commands and to start the implementation of

the commands.

Routing routines check the blocks for validity and queue

the block to the TCBs if necessary. These routines also

purge the data block queues when the network or a

connection is reconﬁgured. Collectively some of the

routing and queue maintenance routines are known as

downline TIP services and upline TIP services.

BLOCK ACKNOWLEDGMENT AND DATA

FLOW CONTROL

The BIP acknowledges downline blocks (examples: a BACK

block is generated to inform the host that a message was

successfully output to a terminal by the responsible TIP, or

accounting data is sent for a PRU block indicating the

block was successfully sent to the terminal). Accounting

data is formatted for the host when an EOI occurs.

PROCESSING SPECIAL CHARACTERS AND IVT

COMMANDS

The BIP provides routines to check special characters

(cancels, breaks, interrupts) in an upline message. If such

characters are found, the BIP takes the necessary action on

the current message (such as discarding the current data).

If IVT commands are found, the BIP calls the IVT processor

to execute the command, to change the network

conﬁguration, and to notify the host if necessary.

The programs also handle all the other kinds of control

blocks except the CMD blocks which are handled by the

service module.

PROCESSING AUTOINPUT

The BIP saves the ﬁrst 20 characters of an autoinput

message from the host so that these characters can be used

to preface the autoinput reply from the terminal.

COMMON TIP SUBROUTINES

A number of common TIP subroutines are provided to:

queue output blocks. The TIP is notiﬁed that

output needs to be processed.

Handle upline break signals from a terminal.

Output operations are halted and the host is

notiﬁed to stop sending output data on this line.

Handle downline break from the host. The TIP will

not send more input data to the host until the host

is again ready to receive data for this line.

Handle a request from the TIP to stop output data

from the host for a given line.

Handle requests from a TIP to escape to ﬁrmware

processing. This is used for the text-processing

operation.

Find the number of characters to be processed.

Save and restore TIP processing entry points so

that a TIP can temporarily suspend processing

while waiting for some external event to occur.

The TIP may be simultaneously suspended for one

output and one input operation.

60471400 G 2-9

Handle a common control relinquishing request.

This assures that return of control to the OPS-

monitor is complete and correct.

FAILURE AND RECOVERY

Several types of failure are possible,

recovery or avoidance technique.

Each requires its own

Host Failure

If a host fails, the NPU and its software must necessarily

stop message processing. Host unavailability is communi

cated to the other ends of all logical links. Also, the NPU

sends an informative service message to all connected,

interactive terminals (and to some other types of terminals)

informing the terminal that the host is unavailable. After

recovery, all logical links are reinitialized and new connec

tions are made.

The host recovers the existing conﬁguration status by means

of status requests to the NPU. Initialization requires the

downline-loading technique described above, followed by

complete reconﬁguration using the status information

recovered from the NPU.

NPU Failure

If an NPU fails, it must be reloaded and reconﬁgured from

the host. Off-line diagnostic tests may be desirable during

this period to help identify the cause of failure. Failure is

detected by means of a 10-second timeout across the

coupler. The NPU is forced to generate a request for load

message.

Recovery consists of a dump (optional), load, and recon

ﬁgure operation. If the initial two load operations fail, the

host does not request a dump after the second or any

subsequent attempt to reload. After n successive attempts

to load, the loading operation is aborted, and the NPU is

ignored until manually reactivated. If the NPU is success

fully loaded and initialized, NS and CS in the host set up all

logical links, lines, and terminals for that NPU which the

present state of the network allows.

Logical Link Failure

Host failure, one of the causes of link failure, was

mentioned previously. Link protocol failure leads to higher

and higher levels of regulation until message trafﬁc ceases

on the link.

A logical link may recover spontaneously (regulation level

drops), or may be reinitialized by the host. In the case of

spontaneous recovery, the logical link protocol allows a

restart without loss of data. Otherwise, all logical connec

tions must be remade. Trunks connecting neighboring NPUs

are a special class of links. Trunk recovery protocol is

handled by the LIP.

Trunk Failure

A trunk failure (such as the trunk connecting the NOS

network to the Public Data Network) is detected by a

failure of the trunk protocol. All data queued for

transmission on the trunk is discarded. The failure is

reported to the host. The trunk protocol detects the trunk

recovery. The logical link protocol determines when the

trunk can again be used for data block transmissions.

Line Failure

Lines are disconnected and terminal control blocks (TCBs)

associated with the lines are deleted. A line failure is

detected by abnormal modem status or by line protocol

failure. The change of status is reported to CS in the host.

A line cannot recover spontaneously. CS (which owns the

lines) deletes the supported TCBs. Then CS disables and

reenables the line, using the appropriate service messages.

When line status changes to operational and this is reported

to CS, CS attempts to conﬁgure the supported terminals.

Terminal Failure

Terminal status is reported and messages are discarded.

TCBs are not released. Once terminal failure has been

detected, possible terminal recovery is monitored by a

periodic status check or diagnostic poll made from the NPU

to the terminal. Terminal recovery status is reported to CS.

DIAGNOSTICS

Three types of diagnostics are associated with the NPU:

inline, on-line, and off-line. Only the inline diagnostics are

a part of CCP. The on-line and off-line diagnostics are a

part of the network maintenance package, which is optional.

• Inline diagnostics include CE error and alarm

messages, statistics messages concerning hardware

performance, halt code messages that specify the

reason for a NPU failure, and off-line dumps.

• On-line diagnostics provide closed-loop testing of

the circuits connecting the NPUs to the terminals.

These tests are available for installations pur

chasing a maintenance contract.

• Off-line diagnostics are hardware tests for NPU

circuits. They are described in detail in the

Network Processor Unit Hardware Maintenance

Manual.

INTERFACE PACKAGES

CCP provides seven standard interface packages:

• A host interface package (HIP) handles the

host/NPU channel. This channel uses high-speed

transfers to move 16 bits of data at a time

between the PPU and NPU memories. These

parallel data transfers do not use data assurance

techniques since the channel's noise level is low.

Data on this channel is in IVT/PRU format. The

code is transparent to the HIP, except that an 8-bit

byte is assumed. The interface requires a CYBER

70/170 host coupler hardware unit.

• A LIP uses a high-speed link to move messages

from any kind of a terminal between a local and a

remote NPU. The functions of a LIP are shown in

ﬁgure 2-3.

• An ASYNC TIP services TTY-type asynchronous

terminals connected to the network on low/

medium-speed voice-grade lines. Terminals must

be asynchronous. The TIP supports ASCII, IBM

extended BCD, APL, correspondence code, and

variants of these.

^&H^S

.^Sejy

2-10 60471400 G

00&Ss*

MULTIPLEX SUBSYSTEM INTERFACES

UPLINE LOCAL NPU

FRAMES*

REMOTE NPU

_ ASYNC

HOST

BIP LIP LIP TIPS

»-

IVT/PRU

BLOCKS

SELECTS

COUPLER

(HIP)

RECONSTITUTES

LINE-RELATED

IVT/PRU

BLOCKS.

OATA

ASSURANCE

SUBBLOCKS,

PRIORITY

SELECTION.

NON-LINE

FRAMES

- MODE 4 CONVERTS

TO FIRST

STAGE OF

IVT/PRU

FORMAT

HASP

(H JL

—JJKPJ

NU T SHOWN) ...

BIT-SERIAL. HIGH SPEED TRANSMISSIONS

BIT-SERIAL. LOW/MEOIUM-SPEED TRANSMISSIONS

• ALL INTERNAL OPERATIONS ARE WORD ORIENTED

IWORO-2 CHARACTERS)

'FINAL IVT/PRU

CONVERSION

Figure 2-3. Functions of a LIP

A Mode 4 TIP services Mode 4A and 4C terminals

which connect to the network through a cluster

controller (this may be physically incorporated into

the terminal). The controller communicates with

the NPU over a low/medium-speed voice-grade

line. Transfers over a Mode 4 line are

synchronous. The TIP supports ASCII and external

BCD codes.

The HASP TIP services any terminal or device

connected to the network through a HASP

workstation. The workstation communicates with

the NPU over a low/medium-speed voice-grade

line. Transfers over a HASP line are synchronous,

using a variant of the BSC protocol. The TIP

supports EBCDIC code.

The Binary Synchronous Communications (BSC) TIP

supports IBM 2780 and 3780 batch terminals. The

terminals communicate with the NPU over a

low/medium-speed voice-grade line. Transfers

over a BSC line are synchronous. The TIP supports

EBCDIC code.

The functions of an ASYNC, Mode 4, BSC or HASP

TIP are shown in ﬁgure 2-4.

• An X.25 TIP together with a PAD subTIP services

TTY-type asynchronous terminals connected to the

network through an X.25 public data network

(PDN). The PDN communicates to the NPU over a

high-speed synchronous line; terminals commu

nicate to the PDN over asynchronous low/

medium-speed voice-grade lines. On the terminal

side, the PDN must provide a packet

assembly/disassembly (PAD) access. The functions

of the X.25 TIP are shown in ﬁgure 2-5. The TIP

supports ASCII code.

HARDWARE USED BY INTERFACE PACKAGES

Table 2-3 summaries the hardware characteristics and

functions of each of the interface packages.

SOFTWARE USED BY INTERFACE PACKAGES

Table 2-4 summarized the software characteristics and

functions of each of the interface packages.

HOST INTERFACE PACKAGE

The host interface package (HIP) handles the protocol

governing transmissions between the host and the NPU. The

route of all such transmissions is through the coupler

hardware. This hardware contains three registers which

have status or command information, one register that

contains the NPU address of the data to be transferred, and

one set of lines connecting the host peripheral processing

unit (PPU) buffer to the direct memory access (DMA) buffer

In all cases the format of the byte in the host is 12 bits, and

the associated word (2 bytes) in the NPU is 16 bits. For

address and data information the 12-bit host byte does not

directly use the upper four bits, making the host interface

effectively an 8-bit byte. Two bytes are needed to make the

associated 16-bit NPU word. For the three status-type

registers (coupler status, orderword commands, and NPU

status), only the lower 12 bits are used.

The NPU memory address register is set up by the NPU for

upline or downline data transfer. The register is set up by

the PPU when dumping the contents of the NPU to the host.

In that case, the host uses the supplied address as the

starting address of the next block of main memory to be

dumped.

60471400 G 2-11

LOCAL NPU

HOST

IVT/PRU

BLOCKS

BIP TIPS MUX

CONVERTS

BIT-SERIAL

TO/FROM BIT-

PARALLEL

(CHARACTERS),

LOW-LEVEL

LINE-ERROR

HANDLING

FINAL

CONVERSION

TO IVT/PRU

CONVERT CODE,

FORMAT BUILD

1ST STAGE IVT/

PRU BLOCKS,

HIGH-LEVEL

ERROR

HANDLING

PASS BLOCKS

TO TIP,

ACKNOWLEDGE

BLOCKS CONVERT CODE,

FORMAT TO

TERMINAL

TYPE HIGH-

LEVEL ERROR

HANDLING

(HIP FUNCTIONS

NOT SHOWN) *— LOW/MEDIUM-SPEED

BIT STREAM IN

TERMINAL FORMAT

INTERNAL OPERATIONS ARE WORD-ORIENTED

(WORD=2 CHARACTERS)

A^&^ts.

Figure 2-4. Functions of a TIP (not X.25 TIP)

LOCAL NPU TIPl AND LIP

OPS LEVEL

BIP

BLOCK SEPARATES

INTERFACE MESSAGES INTO

TO HOST LINE-RELATED

BLOCKS

COLLECTS

BLOCKS

FOR FRAMINC

MUX LEVEL

CONVERTS

BETWEEN

FRAMED BIT

STREAM AND

LINE-RELATED

BLOCKS

BIT

SERIAL

HIGH

SPEED

FRAMES

MUX LEVEL

COLLECTS

IVT/PRU

BLOCKS FOR

FRAMING

DISTRIBUTES

IVT/PRU

BLOCKS TO

TIPl

TASK CONVERTS

ALLOCATION BETWEEN

HIGH-LEVEL BIT-SERIAL

ERROR AND WORDS

PROCESSING (BLOCKS)

FORMAT/

COOE

CONVERSION

X.2S TIP AND PUBLIC DATA NETWORK (PON)

LOCAL NPU PDN

TASK

ALLOCATION

SUBTIP (PAD)

TEXT ft

FORMAT

CONVERSION

(PACKETINGI

(TERMINAL

TO/FROM

IVT)

PACKET

PROTOCOL

HANDLING

FRAME

FORMATION

FRAME

DISCARDING

LEVEL 1

MULTI

PLEXED

INPUT

AND

OUTPUT

CONVERT

TO/FROM

BIT-SERIAL

BIT

SERIAL

HIGH-

SPEEO

FRAMES

FRAME AND

PACKET

ASSEMBLY/

DISASSEMBLY

-LOW/MEDIUM-

SPEED

BIT-SERIAL

STREAM

r38»y

Figure 2-5. Comparison of TIP/LIP and X.25 TIP Functions

The four principal functions performed across the interface

are:

• The host issues NPU start and stop commands for

the micromemory processor.

• The host loads programs into the NPU to initialize

it or to change its mode (overlay programs).

Dumping the contents of the NPU is usually a part

of downline loading from the host.

• The host or NPU sends one-word function com

mands to the coupler and checks status across the

coupler. One of the status registers regulates

transmission rate across the coupler by rejecting

certain types of messages when the NPU is in

danger of running low or running out of buffers.

• Blocks of data (messages) are transferred both

upline and downline. Service messages are a

special type of control that uses block data

transfer techniques.

MICROMEMORY START AND STOP COMMANDS

The micromemory must be started at location zero. Both

start and stop commands are a special form of service

message.

CONTROL WORD TRANSFERS

The NPU sets function commands to the PPU in four

hexadecimal bytes, using one of the status-type registers.

This allows the NPU to check switch status, chain buffers of

data during transfer, clear the coupler registers, read the

other two status-type registers, ready the PPU to read the

status-type registers, and to set the memory address

The PPU uses a 3-bit octal code to transmit functions.

These commands clear the coupler or NPU, start the NPU,

input or output a program during the load/dump phase of

NPU initialization, load the memory address for dump

operations, and set or read the other two status-type

registers.

^*3$tv

2-12 60471400 G

TABLE 2-3. HARDWARE USED BY INTERFACE PACKAGES

Interface

IP Required by Line Type and Line Characteristics

Device To

HIP Coupler PPU on host Every local or front-

end NPU

Channel, 16 bits parallel data plus 18 bits

of address plus control/status lines.

Asynchronous transfers.

LIP Mux Mux Both ends of a trunk High-speed, bit-serial full-duplex, dedi

subsystem subsystem cated 4-wire. Asynchronous requests, syn

chronous transfers. CRC-16 frame check

provided.

Async Mux TTY terminals TTY type terminals Low/medium-speed, voice-grade, bit-serial,

TIP subsystem in classes 1, not connected to a full-duplex, 2-wire, dedicated/dial-up,

2, 4-8 public data network constant carrier. Character-oriented,

asynchronous transfers. Codes: ASCII

(variants), APL (variants), IBM extended

BCD (variants), correspondence code (vari

ant s) . Cha racte rs req uir e s tar t a nd sto p

bits. Character parity provided.

Mode 4 Mux Mode 4A or 4C Any Mode 4 terminals Low/medium/high-speed, voice-grade, bit-

TIP subsystem device in classes 10-13, 15 serial, half-duplex, 2 or 4-wire, dedi

cated/dial-up, constant and controlled

carrier. Terminals can be consoles, card

readers or printers. Terminal clusters

allowed. Block-oriented, synchronous

transfers. Codes: external BCD and ASCII.

Longitudinal parity check on blocks.

BSC Mux 2780/3780 Any BSC device in Low/medium-speed, voice-grade, bit-serial,

TIP subsystem controller terminal classes 16

or 17 half-duplex, 4-wire, dedicated or dial-in,

constant carrier. Terminal devices operate

in batch mode. Terminal can have a simu

lated interactive device. Block-oriented,

synchronous transfers. Code: EBCDIC.

CRC-16 check on blocks.

HASP Mux HASP Any device that can Low/medium/high-speed, voice-grade, bit-

TIP subsystem workstation connect to a HASP

works tat ion (te rm ina l

classes 9 or 14)

serial, full-duplex, 4-wire, dedicated,

constant and controlled carrier. Work

station must be an interactive device.

Terminals can be consoles, card readers,

printers, card punches or plotters. Block-

or ie nted, sy nc hronous tr ansfers. Code:

EBCDIC. CRC-16 check on blocks.

X.25 Mux Public data Any TTY terminal in High-speed, bit-serial, full-duplex, 4-

TIP subsystem network de

vi ces w ith

PAD access

classes 1, 2, or 5-8 wire, dedicated, constant carrier. Public

data network must support packet assembly/

disassembly. Frame-oriented, synchronous

transfers using packetized data. Code:

AS CI I. Characte r p ar ity can b e carried in

text, but is not checked. CRC-16 frame

check provided.

60471400 G 2-13 •

TABLE 2-4. INTERFACE PACKAGE SOFTWARE CHARACTERISTICS

Characteristic

Interface Package

Transfer Format

HIP

LIP

ASYNC TIP

Mode 4 TIP

BSC TIP

HASP TIP

X.25 TIP

Control of

Transfers

HIP

LIP

ASYNC TIP

Mode 4 TIP

Description

Host blocks. Blocks are based on an 8-bit byte in network block format. Longest IVT

data block is 2043 bytes. Full PRU blocks are 640, 1280, or 1920 display code charac

ters, or 320, 640, or 960 ASCII characters. Blocks are in chained buffers (64 words

each). All data is treated as transparent.

A variant of HDLC protocol using frames and subblocks. Maximum frame size is a build-

time selection, and is normally chosen to be 1024 bytes. Subblocks based on buffer

sizes. All data is transparent.

Several variants of TTY character-oriented protocol. Input characters are gathered

into blocks on the basis of a line (character string ending with a carriage return).

Code translation between ASCII and terminal's code. Paper tape/cassette transfers

delimited by the device on/off signal. Transparent mode is available.

Subset of the Mode 4A/4C protocol. IVT block mode used for interactive transfers; PRUB

mode used for batch transfers. Code translation between ASCII and the terminal's code.

Transparent mode is available.

Subset of the BSC protocol. IVT block mode used for interactive transfers; PRUB mode

used for batch transfers. Code translation between EBCDIC and ASCII (IVT) or display

code (PRU). Transparent mode is available.

HASP protocol, a BSC protocol variant. HASP blocks with one or more records used for

both batch and interactive transfers. Upline HASP blocks contain records from one or

more devices. Downline HASP blocks contain records for one device. Code translation

between ASCII and EBCDIC. Format conversion between HASP blocks and IVT or PRU blocks.

Transparent mode is available.

X.25 protocol (TIP level 2) uses synchronous frames containing data packets. At the

terminal side of the public data network (PDN), a PAD access governed by CCITT X.3

protocol transforms asynchronous character streams into data packets and the reverse.

In NPU, level 3, subTIP, and BIP transform packets into IVT blocks and the reverse.

Transparent data transfers (also packetized) permitted in 1200 character blocks.

A hardware handshaking routine prepares transfers. Sending side puts control informa

tion in status registers accessed by both sides; receiving side prepares for transfer

on the basis of the status information. Logic is provided to resolve contention for

channel use.

Asynchronous control frames prepare transfers. All frames contain control information;

information frames contain data as well. Frames are sequenced and acknowledged. Logic

provided to resolve contention for channel use.

Input messages preferred. Typeahead mode saves interrupted output messages until

the unsolicited input is completed and sent to the host. No acknowledgment in either

direction. Special character processing available on input except in transparent

data mode. Input characters echoed on the terminal display without TIP or host

participation.

NPU initiates transfers, terminals respond through cluster controller. If terminal has

an upline message, it notiﬁes the controller which then responds to requests from the

NPU (polling) to read data. Terminals in clusters are handled on a strict rotation

basis, except Mode 4A printers and card readers subordinated to console (interactive

and batch devices cannot be active at the same time). Special character processing for

interactive input data. Print messages (PMs) interrupt printer output; host is noti

ﬁed so that it can send an interactive message to the terminal before printer output

resumes.

• 2 - 1 4 60471400 G

TABLE 2-4. INTERFACE PACKAGE SOFTWARE CHARACTERISTICS (Contd)

Characteristic

Interface Package

Control of

Transfers (Contd)

BSC TIP

HASP TIP

X.25 TIP

(level 2)

Data Movement

HIP

LIP

ASYNC TIP

Mode 4 TIP

BSC TIP

HASP TIP

X.25 TIP

Description

Both ends of line bid for line use (logic is provided to resolve simultaneous

requests). Set up and acknowledgment blocks sent in both directions. Input has

precedence over output and can suspend output until input completes. Interactive

transfers have precedence over batch transfers. Handles print messages as for Mode 4

TIP.

Each terminal has its own data stream. Permission to use the stream is granted by the

HASP workstation. Upline, HASP workstation determines device to be used. Set up and

acknowledgment blocks sent in both directions. Special character processing for

interactive input data. Idle blocks are exchanged when lines not sending data/control

information. Handles print messages as for Mode 4 TIP.

Asynchronous control frames prepare transfers. All frames contain control information;

information frames contain data as well. Frames are sequenced and acknowledged. Logic

provided to resolve contention for channel use.

Direct-memory-access (DMA) data transfers through the host coupler,

asynchronous.

Transfers are

Sending side puts data into subblocks and packs subblocks into frames. Frames are

numbered. Receiving side unpacks frames and restores data to block format. Transfers

are bidirectional and synchronous within the frames.

Data is transferred one character at a time; parity is optional. TIP packs input char

acters into a block. Block is sent upline when block delimiter is received. When a

downline line is ready for transfer, entire logical line is output without interruption

unless unsolicited input occurs.

Data is transferred to/from Mode 4 controller in Mode 4 blocks. Controller routes data

to/from terminals. TIP supplies downline formatting for interactive blocks, and con

verts interactive input into IVT blocks. TIP breaks PRUBs into output blocks, and

assembles input batch data into PRUBs. Trailing blank truncation for card input de

vices. Accounting data for batch devices is generated both upline and downline.

Data is transferred to/from BSC controller in blocks. BSC control function routes data

to/from terminals. TIP supplies downline formatting for interactive blocks, converts

upline interactive data to IVT blocks. TIP breaks PRUBs into output blocks, and assem

bles input batch data into PRUBs. Accounting data for batch devices is generated both

upline and downline.

Data is transferred to/from the HASP workstation in HASP blocks. Upline, several ter

minals can interleave records in a single HASP block. HASP TIP sorts upline records by

connections. TIP moves an interactive record into an IVT block; TIP assembles batch

records into full PRUBs (e xception: partially full PRUBs conta in e nd o f input). Down

line HASP blocks have a single record. PRUBs may be broken into several HASP blocks.

In non-transparent mode, interactive data is translated between EBCDIC and ASCII in

both directions, and batch data is translated between EBCDIC and display code in both

directions. Downline data compression is supplied for batch devices; upline data

expansion is performed on compressed data. Accounting data for batch devices is

generated both upline and downline.

Downline, subTIP handles conversion from network blocks to packets. Packet level (3)

provides groups of packets for level 2. Level 2 frames packets (packets from different

channels are not mixed in one frame) and transmits to PDN. PDN/PAD access is responsi

ble for dismantling frames and packets and moving data one character at a time to ter

minals. Reverse process converts terminal data to IVT blocks.

60471400 G 2-15 •

TABLE 2-4. INTERFACE PACKAGE SOFTWARE CHARACTERISTICS (Contd)

Characteristic

Interface Package Description

Error Handling

HIP

LIP

ASYNC TIP

Mode 4 TIP

BSC TIP

HASP TIP

X.25 TIP

Keep-alive messages assure that channel is available. Recoverable errors are retried

(data parity error s, h ardware timeouts, abnormal termination of tr ansfer) until host

stops NPU and reloads. Irrecoverable errors (memory parity error, memory protect

error, or broken chain of buffers) stop NPU. Host then reloads NPU. Block sequencing

is provided by the agreement between host application and terminal.

An exchange of receive-ready messages assures that the channel is available. Frames

are rejected for noise (bad CRC-16 check), for bad command/response format, for time

outs, or for being out of sequence. In all cases, the bad frame and all succeeding

frames are retransmitted.

Input with bad parity marked but accepted. No retransmission in either direction.

TIP handles timeouts, protocol errors, bad commands, parity errors, and transmission

errors reported by the receiving terminal. In all cases, retransmission is attempted.

If this fails, message movement stops, but attempt is made to restart normal transfers.

For upline data, the TIP recognizes timeouts, bad acknowledgments, and illegal formats.

Bad blocks are reported to the sender by a NAK. For downline data, the TIP recognizes

a transmission failure when it receives a NAK or detects a transmission timeout.

Attempts to retransmit data are made unless an error threshold is exceeded. In that

case, transmissions are aborted. Bad autorecognition data causes a message to be sent

to the terminal.

For upline data, the TIP recognizes timeouts, bad control commands, CRC-16 errors, and

illegal HASP block formats. These are reported to the sender with a NAK block. For

downline data, the TIP recognizes a transmission failure when it receives a NAK block.

In all cases, an attempt is made to retransmit data. If this fails, line is marked

inoperative and the host is informed.

At packet level, detecting a missing packet causes a channel reset. Packets traveling

in the same direction are discarded; no action is taken for data traveling in the oppo

site direction.

At the frame level, frames are retained until acknowledged. Out-of-sequence errors

cause all unacknowledged frames to be retransmitted. Other errors (bad commands/

responses, overlength frames, wrong sequence number) cause the link to reset. Follow

ing resetting, all unacknowledged frames are retransmitted. In case the link is in an

unknown state, it is disconnected and then reconnected. In this case, all frames are

discarded at disconnect time.

Flow Control and

Regulation

Host

HIP

LIP

ASYNC TIP

Input to host is controlled by host resource allocation. Host rejects long blocks

(size greater than 256 bytes) ﬁrst, then shorter blocks.

Host output: Controlled by availability of NPU buffers. Low priority transfers are

regulated ﬁrst, then high priority transfers, and ﬁnally service messages. In ex

treme cases, all output from the host is rejected.

Lo w priori ty tr af ﬁc re gulated ﬁr st if there is a s hortage of NPU buffers; t he n high

priority trafﬁc regulated. Sending LIP responds to receiving LIP's requests for

regulation.

Input trafﬁc is rejected if there is a shortage of buffers or if host is unavailable.

A canned message notiﬁes the terminal user of regulation; another message indicates

when the host is again available.

• 2 - 1 6 60471400 G

TABLE 2-4. INTERFACE PACKAGE SOFTWARE CHARACTERISTICS (Contd)

Characteristic

Interface Package

Flow Control and

Regulation (Contd)

Mode 4 TIP

BSC TIP

HASP TIP

X.25 TIP

Description

In put trafﬁc: TI P st op s polling f or data if ther e is a s ho rt ag e of NP U buff er s or if

host is unavailable. Keyboard is locked when the send signal is entered from terminal

so operator cannot attempt additional input. Terminals again polled for the data when

regulation ends.

Output trafﬁc sent without regulation.

TIP stops input by sending WACK blocks (if the input has started when regulation condi

tions start) or by sending an EOT (if regulation conditions exist when terminal starts

input).

TIP stops all input by sending a wait signal on every active data stream if shortage of

NPU buffers or host is unavailable. If a terminal requests that no more data be sent

on the data stream, NPU passes message to host. Other terminals continue to receive

data.

Both input and output are controlled on three levels.

Input, subTIP level: regulated by host's ability to accept blocks or by buffer short

age. SubTIP requests level 3 not to send additional packets. When shortage ends, sub

TIP restarts the packet level.

Input, level 3: stops acknowledging packets if requested to stop by subTIP. PDN stops

sending packets when n packets are unacknowledged.

Input, link level: if buffers are unavailable, level 2 does not acknowledge frames.

PDN ceases sending frames when n frames (n is a subscription option) are unacknowl

edged; these unacknowledged frames are acknowledged when buffers are again available.

Output, link level: level 2 ceases sending frames when n frames are unacknowledged;

starts sending frames again when there are less than n unacknowledged frames. Requests

are made to level 3 for information blocks (packets) when the level 2 output queue has

room.

Output, packet level: packet level ﬂow is controlled by PDN failing to acknowledge

packets. When the limit (n) is reached, level 3 ceases to send packets and does not

request more data for the subTIP.

Output, PAD access level: PAD subTIP sends data blocks on request from level 3.

work blocks are acknowledged when data is sent to level 3.

Net-

Autorecognition

ASYNC TIP

Mode 4 TIP

BSC TIP

HASP TIP

X.25 TIP

Provided for terminals operating on lines up to 1200 baud. Includes line rate and code

set.

Autorecognition is provided for cluster address, for code type, and for mode type (4A

or 4C).

Sign-on blocks (*/C0NFIG card) are used for autorecognition.

Sign-on blocks (*/CONFIG card) are used for autorecognition.

Autorecognition does not apply.

60471400 G 2-1 7 •

TABLE 2-4. INTERFACE PACKAGE SOFTWARE CHARACTERISTICS (Contd) /tfG^^v

Characteristic

Interface Package

Autoinputt

ASYNC TIP

Mode 4 TIP

BSC TIP

HASP TIP

X.25 TIP

Description

Supported

•Saving the first 20 characters of the output message and appending the input response up to the length of a

logical line.

STATUS WORD TRANSFERS

The control word is set indicating that one of the status-

type registers has been loaded and can be accessed by the

unit on the other side of the coupler. The unit interprets the

control word, reads the status, and acts on the status

information.

The register used for regulation has three status values:

transmit all messages to the NPU (buffer level is above

threshold, so that buffers can be assigned to receive data as

rapidly as the host can transmit data); do not transmit

messages for batch-type devices (buffer availability is

critical, so the heavy demands of chained buffers for batch-

type messages pose a potential hazard of exhausting the

NPU data buffer supply—which causes an unconditional NPU

halt); and transmit-only service messages (neither batch nor

interactive data transfers are allowed; the only transfers

remaining are command/network coordination service mes

sages—all service messages are short and can fit in a single

data buffer of the largest size). Note that all messages use

the direct memory access (DMA) channel of the NPU.

DATA TRANSFERS

For downline transfers, the NPU has assigned the next data

buffer, set up buffer chaining (if necessary), and will receive

sufﬁcient information in the data block header to switch the

block to the proper internal handling or terminal/line/TIP.

For upline transfers, the full message (which may be in

several chained blocks) is ready. The NPU makes the

address of the ﬁrst block in the chain available. As the

blocks are transferred, the chaining bit is inspected. If set,

when one block is transferred, the starting address of the

buffer holding the next block is set in the address register.

Handling of the block protocol on both sides of the coupler

will cause generation of acknowledgment service messages.

This is not a HIP function on the NPU side.

Since the DMA/PPU buffer channel is half-duplex (data can

be sent in only one direction at a time), contention for

channel use is normally resolved in favor of outputting

blocks from the PPU. However, following this transfer, the

protocol provides a 10-millisecond period during which the

NPU can request channel use without the PPU contending

for channel use.

No attempt is made to resend transmissions of less than

block length. A bad block is rejected in its entirety; with it,

the message is rejected. For this reason an entire message

is retransmitted regardless of the number of blocks com

posing it. The message handlers on both sides of the coupler

(that is, the NAM in the host and the HIP in the NPU) are

responsible for retaining messages until they are acknowl

edged as received.

LINK INTERFACE PACKAGE

The link interface package (LIP) module handles transmis

sion and reception on both ends of a trunk; therefore, a copy

of the LIP must exist in both the local and the remote NPU.

The LIP implements a class of the Control Data Corporation

Control Procedure (CDCCP) for information interchange.

The speciﬁc protocol implemented is similar to ISO HDLC

class: a symmetrical, asynchronous response mode (ACM),

with basic numbering range having two-way simultaneous

reject and initialization options (SAB, 2, 5).

Two major types of operations are handled by the LIP:

loading/dumping the remote NPU, and processing data

transmissions over the trunk. Data message transmissions

across the trunk use a unit called a trunk transmission frame

(TTF or frame).

There are three types of frames:

• unnumbered frames which establish the basic trans

mission states between the two nodes (such as

utilization, disconnect, command rejected)

• supervisory frames that establish whether trans

mission/reception is currently possible (ready for

data, not ready for data, or rejected last data sent)

• information frames used to transmit message data;

this class of frames includes frames that are

carrying service messages

Both frame size and data block size are customization time

selections. The information frames themselves are com

posed of one or more subblocks. Each subblock is a buffer of

information related to a single message so that the frame

may be considered as a pocket of information subblocks

containing one or more message parts for one or more

terminals.

2-18 60471400 G

Use of overlay areas is controlled by the host, using

information from the NPU. During normal processing, the

NPU uses all of main memory. However, for rarely used

operations such as initialization, a portion of the main

memory which is normally reserved for assignable buffers is .

instead reserved for special programs. These programs are

temporarily overlaid in memory and are executed on-line.

Terminal message data is always in virtual terminal format

when it is placed in a frame; that is, upline data must be

processed by a TIP in the remote NPU before it is sent over

the trunk, and downline data is not processed by a TIP until

after it is transmitted over the trunk.

Either end of the link may initiate data transmission when

conditions warrant. Once the interfacing LIPs have estab

lished the normal mode, data transmission can begin.

To understand the LIP requirements for message processing,

it must be remembered that a remote NPU has no coupler to

the host, and therefore no HIP. Terminal data passes

through the multiplexer twice: once in terminal format as

it passes between the terminal and the NPU, and once in r/T

or PRU as it passes between local and remote NPUs. Upline

data in the remote NPU is demultiplexed and passed to the

appropriate TIP for conversion to IVT or PRU format.

Completed, converted messages are passed to the LIP for

framing and then passed through the multiplex subsystem,

over the trunk to the local NPU. Trunk transmission rate is

up to 19200 bps.

In this local NPU, upline data from the trunk is received by

the LIP and reconstructed into a message in (chained)

buffers. Then it is passed to the HIP for transmission to the

host. Downline data is taken from a trunk message data

buffer, assembled into frame format by the LLP and sent to

the remote NPU. Once it is demultiplexed by the

LIP/multiplex subsystem, it is in r/T or PRU format and is

ready to be passed to the appropriate TIP for conversion to

terminal format and processing.

LOADING/DUMPING OF REMOTE NPU

The local NPU must process the load/dump operation in its

overlay area. The program information is transmitted

to/from the local NPU overlay area in block form. The local

LIP passes the programs (downline) and receives main

memory contents (upline) in frame format. The remote NPU

LIP is responsible for stripping the frame information from

the downline subblocks and loading these subblocks (parts of

programs) at the location indicated by the host. For

dumping, the LIP is responsible for placing the main memory

contents, starting at the address indicated by the host, into

frames and sending the frames to the local NPU.

Conﬁguring the remote NPU is handled by service messages,

as in the case of conﬁguring a local NPU. The service

messages are transmitted across the trunk in the same

manner as any other message data.

TRUNK TRANSMISSION PRIORITIES AND

REGULATION

A high or low priority is assigned to each frame. This is the

same priority scheme discussed previously for NPU regula

tion: high priority is associated with interactive terminals

and low priority is associated with batch terminals. Each

time a new frame can be transmitted the LIP scans the high

and low priority queues. If high priority data is waiting, it is

always transmitted ahead of low priority data.

On input (in either the local or the remote NPU), data from

the multiplex subsystem which services the trunk can be

rejected if the number of available buffers has dropped to

the threshold level. First low-priority trafﬁc is rejected,

then high-priority trafﬁc. Supervisory frames are not

included in this priority scheme. These frames contain some

command/status information, but do not include most

service message instructions which are treated as high

priority. Thus, some service messages can be rejected while

other command/status information still passes over the

trunk.

TRANSMISSION ASSURANCE

The CDCCP protocol requires that each frame be acknowl

edged. Since several frames may have been transmitted

before an acknowledgment for a given frame is generated,

all frames up to and including the last properly acknowl

edged frame are retransmitted. No frame is released from

the sending NPU until it is properly acknowledged. Frame

checking is provided by a cyclic redundancy checksum (CRC)

which is generated by the sending LIP and included at the

end of each frame.

TERMINAL INTERFACE PACKAGES

A terminal interface package (TIP) interfaces the terminal

data (messages) to the network. The TIP's interface to the

terminal or a controlling device is through the hardware,

ﬁrmware, and software of the multiplex subsystem. The

TIP's interface to the system is through line control blocks

(LCBs) and terminal control blocks (TCBs). A user

interface allows the terminal operator to change an

interactive terminal's parameters (such as page width and

length, cancel and break characters, and others).

Each TIP has the general ability to handle the protocol for

its terminal type. Specialized additional information for

any real terminals that do not ﬁt the basic TIP processing

pattern is contained in the TCB for that terminal. This

gives the standard TIPs sufﬁcient ﬂexibility to handle

many terminal variations.

A TIP includes both hardware and software elements. In

interfacing with the communications network, the

principal concerns of the TIP are mode control and error

control with most of the software elements devoted to

exception processing.

Batch and interactive protocols are treated differently:

• For interactive output in TIPs which support only

interactive devices, TVT data is queued to the TIP

which converts format and code and then passes

the information directly to the terminal (ASYNC

TIP) or to another network (X.25 TIP).

• For other protocols, downline rVT blocks or PRUBs

are transformed into terminal transmission blocks

and are then returned to the BIP. The BIP

requeues the blocks to the terminals in interactive

or batch queues. The TIPs pass the blocks to the

terminals through the multiplex subsystem.

• One upline TIP (ASYNC) converts input data

directly into IVT blocks and passes this to the

host. Other TIPs have multistage upline

processing. During the ﬁrst stage, data is

collected. During later stages data is formatted in

PRUBs or IVT blocks as appropriate. At the same

time, data on channels which service more than

one device have the data segregated by connection

number.

60471400 G 2-19

Methods are supplied for either the terminal user

or the host to interrupt messages.

ASYNC TIP

The asynchronous TIP supports dedicated and dial-up

asynchronous lines servicing teletypewriter-like terminals

operating at standard rates in the range 110 to S600 baud.

The TIP supports the following codes: ASCII, Tele

typewriter-paired APL ASCII, Bit-paired APL ASCII,

External BCD, External BCD APL, Correspondence, and

Correspondence APL. Transparent mode is also available.

The TIP provides software support for teletypewriters, for

2741 terminals, and for teletypewriter-compatible CRTs

operating in an interactive mode with host applications

programs.

There is a build-time option that excludes support of the

IBM 2741 terminals and terminals which use APL code.

This option makes a considerable amount of additional

NPU memory available for message processing. If the

user attempts to use APL features that were not included

in the build, a rejection message is generated by CCP.

The interface between the host and the TIP is handled by

the interactive virtual terminal. The TIP handles the

interface to the terminal through the multiplex subsystem.

The Async TIP supports a terminal-to-virtual transform

for seven types of terminals. To expand the usefulness of

this TIP, a method is provided for the user at a terminal

or a connected application to vary parameters and

operating modes for any of the seven terminal types. This

provides terminals which differ in detail from the

terminal types. The terminals explicitly supported by the

Async TIP and the seven associated classes are:

Terminal Model

Class Manufacturer Number

1Teletype M33, 35, 37, 38

2CDC 713-10

4IBM 2741

5Teletype M40/2

6Hazeltine 2000

7CDC LIAT 751, 752, 756

8 Tektronix 4014

Line types supported are:

• dedicated or dial-up

• two- or four-wire

• full-duplex

The terminal type is supplied by the user at the terminal

or by the host software, as are any further variable

parameters or modes. The TIP is prepared to receive

input at all times (type ahead mode); therefore, the TIP

attempts to deliver output whenever available, unless

input is currently active, a page-wait condition exists, or

an auto-input block has been output and the reply

information (which must be placed in the output block) has

not been returned with the requested information. When

input is detected during an output cycle, the TIP suspends

output operation. Later, this output is sent from the

beginning of the logical line, unless the input was one of

the user break commands.

IBM 2741 keyboards are locked after each logical line is

input and the TIP does not unlock the keyboard until one

or more messages have been output. Therefore, if an

operator at a 2741 terminal wishes to use the type ahead

mode when the keyboard is locked, he must press the

ATTN key to unlock the keyboard so that the type ahead

data can be entered.

Operators at all terminals have the responsibility for not

using the type ahead feature if either auto-input or

special edit mode (see appendix H) are currently being

used.

All input and output in the character mode is transformed

between the terminal and virtual terminal characteristics

(code conversions, format effectors, format effector

delays, line delimiters, special character recognitions,

etc.). The transparent mode is available to suppress this

transform where desired.

Autorecognition allows the TIP to determine both the

terminal's transmission rate (if the rate is between 110

and 1200 baud) and the terminal's current code set. To

activate the autorecognition function, the user at the

terminal presses the carriage return key after the

connection is established. This generates the appropriate

character at the terminal, which is placed on the line at

the terminal's normal line speed. The TIP samples the line

at 800 baud. Depending on the speed of the line, one or

more different characters will be sensed by the TIP. The

TIP uses the received character to detect the true

transmission speed of the terminal.

After the TIP resets the communications line adapter to

the correct baud rate, the TIP sends the terminal two line

feeds to inform the operator that character set

recognition can begin. The operator responds by pressing

the ) key and then a carriage return (ASCII terminal

operators have the option of pressing only the carriage

return).

If the TIP detects a terminal using a code set that is

supported by the TIP but not available in the current

variant, the terminal receives the message,

"UNSUPPORTED CODE SET." This message is sent in the

terminal's code set.

After determining the code set, the TIP sends two more

line feeds to the terminal to inform the operator that

autorecognition is complete. At the same time, the TIP

sends a line operational service message to the host. This

message contains the line speed and terminal character

set. See appendix C of the CCP System Programmer's

Reference Manual.

The user has one minute to enter each of the requested

responses. If he fails to do so in this period, or if the code

set is unsupported in the CCP variant, the line 4s

disconnected.

Any terminal operating at a speed greater than 1200 baud

must be dialed into a port where the communications line

adapter is designed to operate at that particular speed.

Input Processing

The basic input is the logical line (data followed by line

feed/carriage return) or a physical line width of the

device (number of characters in the line; for instance an

80-character line width on the CRT). Output is allowed

only when input processing has a pause longer than 200

milliseconds following a line end. Output is interrupted if

input starts during an output operation.

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2-20 60471400 G

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Parity is checked and the parity bit is stripped from the

data character. Certain other control characters are

discarded from the date (e.g., nulls). The input data in

whatever form is converted to 7-bit ASCII form unless

transparent mode has been selected.

Backspacing control is provided. Input characters within

the current line which are corrected by subsequent

backspacing are discarded.

The operator can cancel the current line by entering the

cancel character (see appendix H for deﬁnition of the

character). The TIP discards the line and conﬁrms the

change by sending a *DEL* message to the operator.

Note that if the terminal is in special edit mode (appendix

H), backspace, linefeed, and cancel characters are sent to

the host as data; the TIP does not perform the control

action which these characters usually cause.

Auto-input is provided. The output block is held while the

terminal operator generates input data in response to

output data. Then the ﬁrst 20 characters of the output

data are chained to the front of the input block and all of

this data is returned to the host as the new input data

stream. Further outputs are inhibited until the responsive

input data is generated. The operator may stop the

auto-input mode.

For keyboard inputs, the TIP provides logic to process line

feed, carriage return, cancel, start of text, and upper/

lowercase shift. Paper tape input is supported.

Output Processing

A single data block may contain several logical lines. The

TIP ﬁlls the lines with nulls as required. Paging format

effectors (FEs) are supported, as are upper/lowercase

shifts. The TIP converts the ASCII terminal code from

the r/T character set to the character set of the terminal.

A page-wait option feature for CRT output allows the

user to view the display as long as he wishes. A page-over

feature warns the viewer that there is more data in the

message even though the current page is not full. Paper

tape output is supported.

User Interface

The TIP supports the standard message input and output

formats for TTY devices. The TIP also allows the

operator at an interactive device to change some

parameters during IVT processing. The commands and

their effects are given in appendix H.

MODE 4 TIP

The Mode 4 TIP interfaces devices using Mode 4A or 4C

protocols to the network. Not all features of the Mode 4

protocols nor all features of supported terminals are used.

A typical Mode 4 device would be the card reader, printer,

keyboard, and CRT display of a CDC 200 user terminal

(UT). Mode 4 devices that have card readers and printers

as optional devices are considered to be 200 UTs even

though they may actually be CDC 731, 732, or 734

terminals.

Table 2-5 shows the Mode 4 equipment supported by the

TIP and the mode and associates each device with batch or

interactive operation. Some variations exist in the

terminology associated with Mode 4 devices. Table 2-6

presents the equivalent terms.

TABLE 2-5. MODE 4 COMPONENTS

Terminals Devices

Type ID Type ID

4A 200UT

731

732

734

CRT & Keyboard

Printer

Card Reader

CRT & Keyboard

Printer

Card Reader

CRT & Keyboard

Printer

Card Reader

CRT & Keyboard

Printer

Card Reader

Interactive

Batch

Interactive

Batch

Interactive

Batch

Interactive

Batch

4C 711

714

CRT & Keyboard

Printer

Interactive

Batch

The TIP is insensitive to line speeds; it supports

synchronous lines operating at rates up to 19.2K bps. Lines

may be dedicated (with or without a transceiver) or

switched (dial-up) with a modem. Lines are considered to

be half-duplex; that is, the TIP is either transmitting to the

line or receiving from the line, but not both simultaneously.

TABLE 2-6. MODE 4 TERMINOLOGY

Nomenclature Used

in this Manual Mode 4A

Nomenclature

Mode 4C

Nomenclature

NPU

cluster address

cluster controller

terminal address

data source

site address

equipment controller

station address

control station

station address

station

device address

60471400 G 2-21

Each line can have more than one cluster of equipment and

each equipment cluster can have more than one terminal.

Lines with multiple clusters must be dedicated. Where

multiple terminals are on a line, the TIP services each

terminal in sequential order without priority.

All Mode 4 terminals can have both interactive and batch

devices attached. The Mode 4 TIP supports remote batch

terminals as separate but dependent devices. The

dependencies are reported to the host on demand when a

conﬂict occurs.

Mode 4 Autorecognition

The TIP performs autorecognition when requested by the

host. This procedure determines the code set of the

terminal (ASCII or external BCD) and mode (Mode 4A or

4C). Autorecognition causes the TIP to return a service

message to the host which contains the following

information:

terminal type

cluster address

terminal address

device type

Multicluster autorecognition is not supported.

Autorecognition ﬁrst determines the cluster address. A

poll message allows the caller to hear an audible tone. The

modem is allowed time to stabilize after the Modem Data

switch is depressed.

To complete autorecognition during dial-up procedures, the

remote operator presses the SEND key on at least one of

the displays in the cluster. This allows code set

recognition through the use of an escape code in a read

message.

If the terminal uses BCD code, autorecognition is complete

at this point. If the terminal uses ASCII code, the TIP

sends a conﬁguration poll. An error response or no

response indicates the terminal is Mode 4A. A read

response indicates the terminal is Mode 4C.

A line status (operational) service message is sent to the

host to complete autorecognition.

Mode 4 Data Handling

Interactive data is passed to/from the IVT interface; batch

data is passed to/from the PRU interface.

• Input data: the TIP polls the terminal to collect

data that is ready to be input. The host requests

polling, but the TIP controls the actual polling for

data. A further throttling of input can occur if

the NPU is regulating data input as a result of a

low buffer availability condition.

• Output data: the TIP delivers interactive output

to the display and batch output to a printer.

Output is delayed if the printer is not ready.

• Error processing: the TIP performs recovery for

line or terminal errors. If immediate recovery is

not possible, the TIP reports the error to the host.

Host Interface

rVT or PRU blocks are used at the host interface. The TIP

processes each line as an independent data channel.

Devices on a terminal are checked for data in the sequence

the devices were conﬁgured. The card reader and printer

of the 200 UT are treated as separate terminals, but the

console must be conﬁgured before the card reader and

printer can be conﬁgured.

The terminal status of Mode 4C terminals is solicited

before the TIP services devices on the terminal. The

terminal returns the status of all the connected devices

when requested. Console status indicates whether a read

message is requested. Printer status indicates ready or

busy condition. Status is saved in the TCB and is used to

determine the action to be taken when subsequent events

occur.

IVT Interface

The IVT interface to the Mode 4 TIP supports the CRT and

keyboard which are collectively referenced as one device,

the console.

Selecting the Mode 4 Console

Console activity is started by a start input command,

console output data, or an input batch interrupt for the

console. Console activity remains active and the TIP polls

for input. Upon arrival of batch start or resume

commands, console activity ceases and batch activity

commences. When batch activity ceases due to normal

processing of end of data and no further data is present,

the TIP sends a clear write to the console and starts polling

the console for input.

For the Mode 4A terminals, using the console interrupts

the card reader connection and the printer connection.

The TIP inhibits any further batch input or output activity

until it receives a resume type of command from the host.

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Mode 4 Interactive Input

When a start input command is issued to a Mode 4A

terminal, the cursor is moved to the left-most character

position. This command also clears the terminal

transmission buffer of any previous card or print block.

Polling for input continues until the terminal is deleted

from the system conﬁguration, an error occurs, buffer

regulation occurs, logical link regulation occurs, or a stop

input command is received. A stop (STP) block is sent

whenever a communication error is detected; a start

(STRT) block is subsequently sent when the error condition

disappears.

The TIP polls the Mode 4C console for input only when a

read request is indicated in the terminal's status.

It is possible for parts of a message to repeat on a 711

terminal in certain types of error conditions.

The operator can cancel part of a line by using the CN

character (see appendix H). If this capability is used, the

TIP conﬁrms the cancellation by sending a *DEL* message

to the interactive device. See appendix H for the

alterations to the IVT interface which may be entered from

a terminal.

2-22 60471400 G

Interactive input from the console can include multiple

logical lines. The lines are separated by CRs.

The TIP allows autoinput. The ﬁrst 20 characters of the

autoinput message from the host are saved and are

preﬁxed to the reply from the console.

The TIP supports transparent input, but this input applies

only to the ﬁrst message following transparent selection.

The Mode 4 frame control characters are removed, but no

other translation occurs. The cursor is not repositioned to

the left margin following each input, and the keyboard is

not unlocked. Since any further polling would result in

retransmission of previous data, polling ceases. The host

must request that polling resume by sending output or a

start input command.

The TIP removes any E2 or E3 codes from Mode 4A cluster

transparent data. The data is processed without

transforms. E-codes and MTIs for Mode 4 protocol are

described in the CCP System Programmer's Reference

Manual.

An operator at a Mode 4 console can change the following

r/T parameters for his terminal:

• Terminal class

• Page width and page length

• The characters used for cancel, r/T control, and

user breaks one and two

• Input device for transparent mode (Mode 4C only)

• Page wait feature

The operator can also send a message to the NOP console.

Each IVT command (including the message to the NOP

console) is preceded by the control character and followed

by a carriage return or an end of message. Multiple line

inputs can have an IVT command only in the ﬁrst line. If

the IVT command in a multiline input is a request for

transparent input, transparency will not be applied to the

current set of input lines, but will be applied to the next

message.

Mode 4 Interactive Output

The cursor is returned to the left margin following each

output of a logical line. For a Mode 4A console, any ASCII

control character is replaced with a blank, and lower case

characters are folded into upper case. For a Mode 4C

console, a full 128 ASCII character set is supported.

The format effector transforms performed by the TIP for

both interactive and batch devices is given in the CCP

System Programmer's Reference Manual.

The IVT transform is not performed on transparent output

data. However, the Mode 4 frame control is added to the

data, but no code or format effector conversion is

performed. The parity bit for each character is also added

before the data reaches the line. Autoinput and page wait

are supported for transparent data. However, page wait

occurs following each MSG block only.

The console operator requests a message break by using

either the user break one or two character.

The page wait feature assures that output is delivered at a

readable rate. Data from the host is displayed on the

screen until the end of page is reached. Page turning is

accomplished whenever the console operator responds with

a request for the next data display.

Card Reader Interface

The Mode 4A card reader is activated by sending a

command to the TIP to start accepting input. The TIP

polls the card reader for data.

Upline data is translated and trailing spaces are stripped to

the ﬁrst even character boundary following the last data

character. The data is stored in buffers which are

subsequently passed to the BIP. The BIP builds the PRUBs

to be transmitted to the host.

The TIP indicates end of card in standard host ﬁle format.

If the last non-blank character is on an odd character

boundary, one blank is inserted. Two to ten binary zeros

are then added to insure that the host can decode end of

card and also to insure that the data stream ends on a

modulo ten character boundary. If the last data character

of the card is a colon in the 64 character set, the TIP

inserts one or two spaces.

The TIP counts each card. Polling continues until an abort

input occurs, a slipped card is detected, a console interrupt

occurs, the card reader becomes not ready, or an EOI card

is read (6, 7, 8, 9 punch in column 1 or /*EOI in columns

1-5). The TIP handles these events as follows:

• Abort input: card reading stops and accounting

data is sent to the host. If the printer is not

active, the TIP polls the console. If the printer is

active, the cluster remains in batch mode. Card

reader input restarts upon receipt of a start input

command from the host.

• Slipped card: host is informed with an input

stopped, card slip command.

• Card reader not ready and last card read not an

EOI card: the TIP stops polling and notiﬁes the

host. Polling resumes when the TIP receives

another start input command from the host.

• Console interrupt: the TIP reports that input is

stopped and sends a batch interrupt to the host.

Card reading resumes when the host sends a

resume input command.

• EOR card read: TIP checks columns 2/3 or 6/7 for

level number and adds this information to the

PRUB. Since an EOI or EOR card ends a PRUB, it

is possible for a short PRUB to be sent to the host.

• EOI card read: the current data, including

accounting data (card count), is sent to the BIP.

The BIP passes the data to the host in a PRUB and

the TIP continues polling. If an EOI is read and

the card reader is found to be not ready (empty),

the TIP notiﬁes the host that the card reader is at

end of a data stream. To get more card data, the

host sends another start input command to the

TIP.

j S v ,

60471400 G 2 - 2 3 •

Printer Interface

The printer is activated by sending downline PRUB data to

the BIP. The BIP passes the PRUB to the TIP. The TIP

transforms the PRUB into transmission blocks (blocks of

data that ﬁt the particular printer buffer being addressed)

and returns it to the BIP. The BIP adds the transmission

blocks to the TIP's queue and, if necessary, notiﬁes the TIP

that data is ready for the printer.

As the TIP sends blocks to the printer, the BIP monitors

the queue. When necessary, the BIP notiﬁes the host. The

host can send another PRUB if one is available.

When Mode 4A printing has completed and the accounting

message has been generated, the TIP returns to polling of

the console for inout if the card reader is not active.

Otherwise, the terminal remains in batch mode.

Skipping Printer Data

Interrupt commands from the host can cause the TIP to

skip a speciﬁed portion of the printer data. The point in

the data stream where the skip is to end is marked. After

receiving the interrupt, the TIP continues to receive data,

but discards all of it until the end skip marker is received.

Then the TIP sends accounting data to the host.

Printer Busy

Busy status permits the operator to stop printing, to

inspect the printed output, and to resume printing without

console input.

If a printer is ready but busy, the TIP holds data and

periodically checks status. When the printer is again

ready, the TIP resumes printing. The host is not notiﬁed.

Since some Mode 4A printers do not always report printer

not ready status, a different method is used. To interrupt

printing or to generate a ready status, the operator presses

the interrupt key. This toggles the printer between ready

and busy status.

Mode 4C printer status is determined by the terminal

status request. Printer not ready condition is not reported

to the host; printing automatically resumes when the

printer becomes ready.

In no case does the remote terminal operator receive a

console message indicating that the printer is not ready.

The printer should normally be left in the ready state to

avoid unnecessary recovery processing.

Page Eject

Two types of Mode 4C printers are supported: impact and

nonimpact.

The impact printer supports page eject and is controlled by

vertical carriage control characters.

The nonimpact printer does not support page eject, so the

TIP formats a virtual page image. The number of lines on

the page is speciﬁed when the device is conﬁgured. Sixty

lines is the default page length; six lines separate pages.

Therefore, the TIP varies the number of line feeds it

generates to support page eject.

Print Message

If a print message is received (TIP detects PM at the

beginning of a print line), the TIP builds a separate PM

message and sends it to the BIP, which in turn sends it to

the host. This allows the host to send messages to the

console before continuing the printed output. When the

host sends an interrupt resume command, the TIP restarts

printing with the print line following the PM line.

Mode 4 Error Handling

When the TIP detects a failure that cannot be corrected by

a set number of retry attempts, the terminal is reported as

failed and long-term error recovery begins. For Mode 4A

terminals, failure of one device causes failure of all

devices on the cluster.

Recovery attempts occur every 10 seconds during

long-term error recovery.

BINARY SYNCHRONOUS COMMUNICATIONS

(BSC) TIP

The BSC TIP provides data interchange between a host

application program and a remote IBM 2780, 3780 or

compatible batch terminal. In addition to the terminal's

batch capabilities, BSC terminals simulate an interactive

console device by sending interactive input from the card

reader and receiving interactive output on the line printer.

Exchange of information between the NPU and a terminal

uses the point-to-point binary synchronous communications

protocol with contention resolution (not all features of that

protocol are supported). The NPU converts BSC batch data

to/from PRUB format, and BSC interactive data to/from

IVT blocks. The normal code of a 2780/3780 is EBCDIC.

Provision is made for transmitting to or receiving from

these terminals in transparent mode.

2780 and 3780 have unique subTIP types. For the purposes

of the application interface, the 2780 and the 3780

terminals have exactly the same attributes as HASP

terminals.

BSC terminals can be attached to an NPU through

dedicated or dial-up lines. The TIP is insensitive to line

speeds; it supports synchronous lines operating at speeds up

to 19200 bps. All lines are treated as half-duplex, that is,

the TIP is either transmitting or receiving but not both

simultaneously. Each BSC line is connected to one 2780 or

3780 terminal. A terminal consists of:

• A required card reader which sends interactive as

well as batch input data

• A required line printer which receives interactive

as well as batch output data

• An optional card punch

Terminal Device Selection

The following rules apply to terminal device selection:

• Input has precedence over output

• Interactive data has precedence over batch data

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• 2 - 2 4 60471400 G

Batch card reader input is allowed if the simulated console

input is not active. Batch output can be interrupted to

accept card reader input; the interrupted output is resumed

when input ends. Card reader input (either batch or

interactive) is not interruptable.

A new batch output can be started if no input is active and

no simulated console data is queued. If the terminal user

interrupts to send card reader input, the batch output is

suspended. Batch output restarts when an upline end of

transmission (EOT) is received, and continues until the end

of job (EOJ) before any new batch output can be started.

There is one exception: a print message (PM). Print

messages are explained in the Mode 4 TIP description.

Batch Input Characteristics of 2780

and 3780 Terminals

Terminals normally operate in non-transparent mode. If

the feature is supported by the terminal, a terminal can

operate in transparent mode. Five types of batch input are

supported:

2780 non-transparent

2780 transparent

3780 non-transparent

3780 transparent

2780/3780 transparent

The BSC TIP checks for data mode information (026, 029)

in columns 79/80 of job deck and EOR cards.

If the host becomes unavailable or the NPU reaches buffer

saturation, the TIP stops or delays input until the reason

for input regulation is removed. If input is already active,

the TIP can delay input by sending a wait/acknowledgment

(WACK). If the regulation occurs before the ﬁrst input

data arrives, the TIP stops input by sending an EOT.

The 3780 non-transparent characteristics are the same as

the 2780 non-transparent characteristics except:

o Job cannot be terminated by an ETX in column 80

of last card.

• For multiple jobs, the last job must be input with

the EOF toggle switch on.

• Trailing blanks are truncated

• Data can be compressed

• Transmission block is limited by character count

(usually 512) rather than record count

The 3780 transparent characteristics are the same as the

3780 non-transparent characteristics except:

• Transparent switch is on

• 80 characters transmitted per card (no truncation

or compression)

The TIP provides another batch input transparent mode for

both 2780 and 3780 terminals. This mode of input can be

speciﬁed only when a terminal is operating in the 2780 or

3780 transparent mode. Characteristics of this transparent

mode are:

• Mode activates when TIP detects TR in columns

79/80 of an EOR card

• Neither EOR or EOI cards are recognized

• Input file is terminated by setting the EOF toggle

switch on

• Terminal transparent switch must remain on until

the ﬁle is ended

The 2780 non-transparent characteristics are:

• First card is assumed to be a job card

• Job is terminated by (1) /*EOI, in columns 1-5, or

(2) an ETX in column 80 of the last card or in

column 1 of the next card, or (3) last card is sent

with the EOF toggle switch on.

• Trailing blanks are transmitted except after EM

or ETX

Blank compression is accepted

Up to seven records per transmission block

Multiple batch jobs can be stacked in the reader.

Each job terminates with a /*EOL Blank cards,

/♦EOR cards and extra /*EOI cards after a /*EOI

are discarded.

The 2780 transparent characteristics are the same as the

2780 non-transparent characteristics except:

• Transparent switch is on

• A full 80 characters are transferred for each card

(one record)

• One record per transmission block.

• The TIP returns to the non-transparent mode for

the next batch job.

• Data is stored in a PRUB without marking record

boundaries (such as 80 column card boundary) or

transmission block boundaries

• Transmission block can be split between PRUBs

Batch Output Characteristics of 2780

and 3780 Terminals

Four types of batch output are supported:

• 2780 non-transparent

• 2780 transparent

• 3780 non-transparent

• 3780 transparent

The BSC TIP bids for the line whenever the host sends

downline data and the line is available. Once downline

data transfer starts, it continues until an EOJ PRUB is sent

from the host or a print message (PM) is detected on the

print stream.

For non-transparent output, the TIP supplies appropriate

carriage control transformations (format effector

processing). The host can supply preprint or postprint

format effectors; BSC terminals support only postprint

carriage controls. The BSC format effector transforms are

given in the CCP System Programmer's Reference ManuaL

60471400 G 2-25 •

Card punch and printer connections appear the same to the

TIP except for punching a lace card and changing data

mode. Punching a lace card and changing data mode are

activated by a batch device ﬁle command from the host.

Three card punch modes are available: 026, 029 and

transparent. PRUBs containing EOR or EOI cause a 7/8/9

card with level numbers or /*EOI card to be punched.

Print message and carriage control are not supported on

card punch connections.

The 2780 non-transparent output characteristics are:

• Streams directed to line printer or card punch

(provided punch option is present)

• Host determines device to receive output

(separate connections for each device)

• TIP converts PRUB data to EBCDIC 64/96

character set

• TIP formats print lines into BSC transmission

blocks

• 1 to 7 print lines (records) per transmission block

• Maximum transmission block size (default is 400

characters)

• Print line is never split across transmission block

boundaries

• Short line is terminated by unit separator (US)

• Transmission block is terminated at the last data

character of a PRUB block that is marked as an

EOR, EOI, or EOJ block

• Blank compression if terminal supports that

feature

The 2780 transparent output characteristics are:

• Transparent output only if output is specified as

transparent (designated transparent by a

preceding command)

• No code conversion or carriage control transforms

• PRUB characters packed into transmission block

until maximum size or EOR/EOI packed (no

record markers)

• Characters in transmission block formatted into

records; record size deﬁned by page width (if

page width ﬁeld is zero, record size limited only

by transmission block size)

• EOR PRUB terminates only the transmission

block; next transmission continues with next

PRUB block and a new transmission block

• EOI PRUB terminates the file

• No EOR or EOI cards punched on card punch

connection.

The 3780 non-transparent output characteristics are the

same as the 2780 characteristics except:

• Number of print line records or card records

limited only by the transmission block size

(normally 512 characters). Short records (print

lines or cards) terminated by the EBCDIC IRS

character

• Trailing blanks in the PRUB record are truncated

The 3780 transparent output characteristics are identical

to the 2780 transparent output characteristics.

Print Message (PM)

The characters PM at the beginning of a print line activate

the print message logic. If the TIP detects a PM, the print

line prior to the PM is sent to the line printer. Output is

then stopped and the host is notiﬁed with a message of 80

or fewer characters. This enables the host to send an

interactive output message to the printer. Batch output to

the printer does not resume until ICMD, resume, or

terminate output command is received.

Interactive Input and Output Mode

The interactive virtual terminal input mode characteristics

are:

• All interactive cards begin with /*; the TIP strips

this interactive card indicator

• r/T commands from the terminal have the special

control character CT=% in the third character

position

• Input is sent to the host as a MSG block

• Interactive input is on a separate card stream

from batch input (inputs must be separated by

EOT)

• No transparent data mode

The interactive virtual terminal output mode

characteristics are:

• Message output preceded by triple space to

position the message for reading

• Message output followed by double space to

position the message for reading

• Interactive output is single spaced

• Message output occurs at input and output file

boundaries or when the printer is stopped for PM

message; all interactive output messages in queue

are delivered before any more batch output

• No transparent data mode

• 2 - 2 6 60471400 G

Autorecognition Summary of HASP Protocol

Autorecognition allows the terminal to report its own type,

cluster address, and terminal address (the latter is used for

the optional card punch). A /*CONFIG card must be the

ﬁ r s t c a r d r e c e iv e d f r o m a t e r m i n a l a f t e r a n

autorecognition line is enabled. Information from this card

is extracted by the TIP and passed to the host. If the TIP

detects a card error, it sends an error message to the

printer. Then the TIP waits for retransmission of the

correct card. The /*CONFIG card format is:

/♦CONFIG, terminal, CO=M, CR=1, LP=1, CP=N

where:

terminal

subTIP (2780 or 3780; default is

2780)

Cluster Address

default = 0) (range 1-255;

Card punch (1 = none, 2 or 3 =

terminal address of punch; default =

Any input immediately following a conﬁguration card is

discarded; input is allowed only after the input connection

is established and started.

IVT Commands

The TIP supports these IVT commands:

• MS, Operator message

• CT, Change control character

An error message is returned to any terminal which sends

an illegal IVT command.

Downline File/Device Commands

The TIP supports the following output ﬁle types:

LP - Display code, ASCII - 96

CP - 026, 029

HASP MULTILEAVING TIP

The TIP provides network interfacing to a HASP

multileaving workstation. A workstation can contain both

interactive and batch devices and has computer-like

functions. The term multileaving describes the

computer-to-computer communications technique used by

a HASP terminal. The system uses fully synchronized,

pseudo-simultaneous bidirectional transmission of several

data streams between computers and requires BSC protocol

as a basis for transmitting HASP blocks.

A HASP terminal consists of a required console, one to

seven card readers, one to seven printers, and one to seven

card punches or plotters (in combination). Each device has

a separate data stream identiﬁcation.

The basic element of multileaved transmission is a

character string which is embedded in a data (message)

block. One or more character strings are formed from the

smallest external element of transmission - the physical

record. The physical records, which serve as input data,

may be of any normal record types (card images, printed

lines, mass storage records, etc.). For efﬁciency in

transmission, each record is reduced to a series of

character strings of two basic types: a variable-length

nonidentical series of characters or a variable number of

identical characters. Since blanks appear frequently, a

special case of the identical character string is the string

of blanks. A string control byte (SCB) precedes each

character string to identify the type and length of the

string. A nonduplicate character string is represented by

an SCB followed by the nonduplicate characters. A

consecutive, duplicate, nonblank character string is repre

sented by an SCB (which contains the character count) and

a single character. For an all-blank character string, only

the SCB itself is required.

The transmitting program segments the data record to be

transmitted into an optimum number of character strings, a

number determined to take full advantage of the identical

character compression. A special SCB indicates the

grouping of character strings which compose the original

physical record. The receiving program then reconstructs

the original record for processing.

In order to allow multiple physical records of various types

to be grouped together in a single transmission block, a

record control byte (RCB) precedes the group of character

strings representing the original physical record. The RCB

identiﬁes the general type and function of the physical

record (input stream, print stream, Data Set, etc.). A

particular RCB type is designated to allow the passage of

control information between the various systems. To

provide for simultaneous transmission of similar functions

(multiple input streams), a stream identiﬁcation code is

included in the RCB. A subrecord control byte (SRCB) is

also included immediately following the RCB. The SRCB

supplies additional information concerning the record to

the receiving program. (For example, if the transmitted

data is to be printed, the SRCB can hold carriage control

information.)

For a multileaving transmission, a variable number of

records may be combined into a variable block size; e.g.,

RCB,SRCB,SCBl,SCB2,...SCBn,RCB,SRCB,SCBl,... Multi-

leaving allows two computers to exchange transmission

blocks containing multiple data streams in an interleaved

fashion. For optimum use of this capability, a system must

be able to control the ﬂow of one data stream while

continuing normal transmission of others. This requirement

is obvious in the case of simultaneous transmission of two

data streams to a system for immediate transcription to

physical I/O devices with differing speeds, such as two

print streams. To meter the ﬂow of individual data

streams, a function control sequence (FCS) is added to each

block. The FCS is a sequence of bits, each one

representing a particular transmission stream. The

receiver of several data streams can temporarily stop the

transmission of a particular stream by setting the

corresponding FCS bit OFF in the next transmission to the

sender of that stream. The stream can subsequently be

resumed by setting the bit ON. In this release multileaving

is used only by the HASP terminal. The host does not

regulate device data; rather the host's output is regulated

by the devices' use of FCS bits.

60471400 G 2-27

For error detection and correction purposes, a block

control byte (BCB) is added as the ﬁrst character of each

block transmitted. The BCB contains control information

and a block sequence count. This count is maintained and

veriﬁed both by the sending and by the receiving systems

to control lost or duplicated transmission blocks.

In addition to the normal binary synchronous text control

characters (STX, ETB, etc.), multileaving uses two

acknowledgment signals, ACKO and NAK. ACKO is the

normal block received acknowledgment and it is also

utilized as a ﬁller by all systems to maintain communi

cations when data is not available for transmission. NAK is

used as the negative response; it indicates that the previous

transmission was not successfully received.

Information blocks are of two types:

• control blocks which contain control information

and the SCB

• data blocks which contain data and the other

control bytes described above

Protocol Operation

The terminal software is loaded and the communications

line is initialized. After the sign-on command is

transmitted, the NPU and the terminal transmit idle blocks

until a function is desired.

When a function other than a console message or console

command is desired, the process initiating the function

transmits a request to initiate function transmission RCB.

The receiving process transmits a permission to initiate

function transmission RCB if the data from the requesting

process can be processed. If the data cannot be processed,

or the function is now in process, the request to initiate a

function transmission RCB is ignored.

When permission to initiate a function transmission RCB is

received, the requesting process begins transmitting data

blocks to the other process. Data blocks are transmitted

until an EOF is encountered. If more data blocks on the

same device stream are to be transmitted following an end

of ﬁle (EOF), the request to initiate function transmission

RCB sequence must be reinitiated. If a request to initiate

a function transmission is not received before data blocks

are received, the data blocks are ignored.

Data blocks are transmitted one at a time. Before another

block can be transmitted, the receiving process must

transmit a positive response in the form of an acknowledge

control block or a data block.

Console functions (operator messages/commands) do not

have to follow the request to initiate-permission to initiate

sequence. A console function may be initialized at any

time when the wait ﬂag in the FCS is not set and the

remote console ﬂag is set.

Control Blocks

Four types of control blocks are used in the multileaving

protocol. These control blocks are:

• acknowledge blocks which contain synchronous

control, data link escape control, and positive ac

knowledgment information

negative acknowledge blocks which contain syn

chronous control and negative acknowledgment

information

enquiry blocks which contain synchronous control,

start of header and enquiring control information

idle blocks which maintain communications; an idle

block is transmitted at least once every two

seconds in the absence of data transmissions

Data Blocks

In addition to the control bytes described earlier, data

blocks contain synchronous, escape, start of header or text,

end of block transmission, and cyclic redundancy check

(CRC) information.

Special short blocks are deﬁned for:

• operator console blocks which deliver console

messages in addition to other control information

• EOF blocks (sign-off indication)

• FCS mode change blocks (for instance, a low-speed

printer has all the information it can currently

handle as input)

•sign-on blocks

• BCB error blocks

Error Handling

Errors are recognized for:

• CRC errors

• illegal block format

• unknown responses

• timeout over the line

• BCB-recognized errors (break in sequence of

transmitted blocks)

For bad downline data, the TIP attempts to retransmit the

block three times. On the fourth failure, the TIP forces a

line inoperative status on the terminal. For upline data,

the TIP will attempt to receive a bad block four times. On

the fourth failure, the TIP forces a line-inoperative status

on the terminal.

Data Conversion

HASP terminals use EBCDIC code; host programs use ASCII

code in IVT blocks and display or ASCII code in PRUBs

(transparent data is permitted for both batch and

interactive devices). Upline, the TIP performs code

conversions at the same time that the data is transformed

to IVT or PRUB format. Downline, the TIP converts data to

EBCDIC when the HASP transmission blocks are generated.

Note that there is no code conversion and minimum

formatting conversion if the message data is transparent.

z^SBs

2-28 60471400 G

HASP Console Conversions

Downline, the TIP accepts IVT messages from the host and

delivers them to the console. Upline messages received

from the console are converted to ASCII IVT format and

sent to the host.

If the last data character is a colon in the 64 character set,

one or two spaces are inserted (depending on character

boundary). In 64-character set, contiguous colons on input

cards should be avoided since two binary zeros signal the

end of card.

HASP IVT Commands

An operator at a HASP console can change the following IVT

parameters for his terminal:

• Page width

• The characters used for cancel, r/T control, and

user breaks one and two

The operator can also send a message to the NOP console.

Card Reader Transparent Mode

Transparent 8-bit characters are expanded from the HASP

compressed format and are stored in the PRUB without

translation or marking card boundaries. Records or

transmission blocks are stored contiguously within the PRUB

and can be split across PRUB boundaries. Data is stored

until an EOF block is received. The PRUB receiving the

EOF is marked as the end of input.

The card reader stream remains in the transparent data

mode. The TIP waits for a start input command to

determine the next input data mode.

HASP Input Batch Data

The card reader is the only HASP batch input device. The

reader is activated by a start input command. A card

reader stream remains active unless terminated by:

• An EOF block from the reader

• An abort input command from the host

• A terminal reconfiguration command from the host

• A workstation or line failure

All data following an abort is discarded until a start input

command is received from the host.

A l*EOl card or EOF block indicates normal termination of

a job; the TIP/BIP terminates the PRUB and sends the

(short) PRUB to the host. The TIP discards any /^Ed cards

following an end of ﬁle.

The HASP workstation does not report a card reader not

ready condition.

Card reader data is transformed to PRUB format in either

transparent or non-transparent mode. Transparent mode is

selected by one of two methods:

• TR in columns 79/80 of an EOR card

• A start transparent input command from the host

If a TR is detected in the input stream, the host is notiﬁed.

In this transparent mode neither /♦EOR (7/8/9 punch) nor

/♦EOI cards are recognized. The file is read until an EOF

block is received.

The HASP TIP examines columns 79/80 of all job and EOR

cards to determine if the code translation should be the 026

or 029 character set (26 speciﬁes 026 set; 29 speciﬁes 029

set). Code translation reverts to the terminal's default code

(a terminal conﬁguration parameter) after a l*EOl card or

EOF block is detected.

Card Reader Accounting Data

Accounting data consists of the number of input cards

received by the TIP. In non-transparent mode, standard text

cards are counted; in transparent mode, the number of

characters received is divided by 80 to calculate the number

of cards.

Accounting data is sent to the host when an EOI is

recognized or when the host aborts the input data stream.

HASP Printer Output Data

Output to the printer is activated by the host sending a

downline data block (PRUB) to a printer. Subsequent PRUBs

are converted to output transmission blocks according to the

BSC point-to-point and the HASP multileaving protocols.

The terminal mode (transparent or non-transparent) has

been previously determined and saved in the TCB. Data is

converted accordingly.

The TIP checks ﬁle limits. If a ﬁle limit is reached, the

host is notiﬁed. The BD? does not send more transmission

blocks to the TIP unless the host restarts the data stream.

The host also has the option of terminating the stream.

Note that ﬁle limits can be changed by a batch ﬁle

command from the host.

HASP Printer Non-Transparent Mode

Non-transparent output data is deemed to have the form of

print lines. The end of each line is marked by an FFig. If

the print line from the PRUB exceeds printer line width, the

excess characters are printed on the next line. Print lines

are never split across transmission blocks. The ﬁrst

character of each line is normally interpreted as a carriage

control character.

EOR cards are examined for level numbers. The level

number is stored in the PRUB.

Card Reader Non-Transparent Mode

In non-transparent data mode, card reader characters are

expanded from HASP compressed format, translated to

display code, and stored in PRUB blocks. The TIP indicates

an end of card in standard host format (insertion of blank

ﬁll to an even character boundary, then ﬁlling with two or

more zeros to reach card character count divisible by 10).

Output of ﬁles is continuous as long as the printer is

available and ready or the last block of a ﬁle is transmitted

and acknowledged. When the terminal acknowledges the

last block of a ﬁle, accounting data is sent to the host. The

host interprets this accounting data as delivery assurance.

If the HASP TIP detects PM at the beginning of a print line,

the TIP terminates the current transmission block and

generates a print message for the host. No more batch data

is sent to the terminal until the host sends the print message

to the HASP console. The host then restarts the print

stream.

60471400 G 2-29

HASP Printer Transparent Mode

Print lines are not detected within the PRUB. Characters

are placed in the transmission block without code

conversion, carriage control, or end of line processing.

However, characters are compressed whenever possible.

Transparent transmission blocks are ﬁlled to the device

width, except for the ﬁnal data record, which may be short.

Printer Accounting Data

Accounting data for a printer consists of the number of

output lines sent to the device. An output line is based on

device width (the host can change device width with a PRU

command). Accounting data is sent to the host after the

EOI block is transmitted and acknowledged or when the host

interrupts and terminates the output stream. In the

termination case, all further output data is discarded until

the TIP receives the terminate marker (see the skipped data

description in the BSC TIP).

HASP Postprint Carriage Control

Files for the HASP printer can have either preprint or

postprint carriage control format effectors. The HASP TIP

converts the pre/post print format effectors to pre/post

print SRCBs, depending on whether the printer has been

conﬁgured as preprint or postprint. Note that some HASP

printers cannot suppress carriage control. These printers

will sometimes generate extra spaces on output and will not

overprint.

HASP Card Punch Output Data

Card Punch output is processed in a manner similar to print

output except:

• There is no carriage control

• Output records have a maximum of 80 characters

• In some cases, a lace card (80 columns of punches

in rows 8, 9,11, and 12) is punched.

Transparent data can be sent to the punch. Transparent

mode is speciﬁed in the same manner as for the printer.

Files are handled as for transparent line printer ﬁles except

a lace card is punched in place of a printer banner page.

Accounting data handling and ﬁle limit checking are handled

in the same manner as for printer ﬁles. The device width

for the punch is 80 characters.

The workstation has similar retransmission ability for failed

upline transmissions. If the TIP receives the same block

incorrectly on several successive attempts, the TD? marks

the line as inoperative.

HASP Terminal Start-Up and Termination

Terminal start-up is accomplished by a three-step process:

• Terminal initialization

• Communication line initialization

• Sign-on

Terminal Initialization

Terminal software is loaded into the workstation and

executed. For an autorecognition line, the workstation

sends a signon record (a /♦CONFIG or /♦SIGNON card). The

signon record format is described in the CCP System

Programmer's Reference Manual.

Communications Line Initialization

The conﬁgure line service message from the host starts line

initialization. Communications between the HASP TD? and

the terminal are established by the following procedure:

• The terminal sends an ENQ

• The TIP returns an ACK

• The terminal sends a sign-on record. If the TIP

detects an error in the card, it sends a message to

the HASP console detailing the error. Then the

TIP waits for resubmission of the card. The TIP

acknowledges a good signon record with an ACK.

The terminal is then ready to do normal processing.

• The HASP TIP passes configuration parameters to

other NPU modules. Then it waits for the batch

devices to be conﬁgured. After each device is

conﬁgured, the HASP TIP allows output data

streams processing. Input data streams processing

does not begin until start input commands are

received from the host.

Signoff Record

A /♦SIGNOFF card from the terminal has the same effect as

an EOF block if the card reader is active; otherwise, it is

ignored.

/^^V

HASP Plotter Output Data

Plotter output is processed in a manner similar to

transparent printer output. Accounting data handling and

ﬁle limit checking are similar to that described for printer

ﬁles.

HASP Error Recovery Procedures

A NAK block informs the

transmission error. receiving process of a

For output errors, the TD? saves the last downline data block

so that it can retransmit the data if necessary. If

retransmission continues to fail after several successive

attempts, the TD? forces the line into inoperative status.

X.25 TIP/PAD SUBTIP

A public data network (PDN) uses the CCITT X.25 protocol

to transfer data over a high-speed link.

The packet assembly/disassembly (PAD) access of the PDN

uses CCITT X.3 protocol to process data from TTY-type

terminals connected to the PDN. Processing consists of

collecting individual characters into packets (upline) or

extracting individual characters from packets to send over

the voice-grade terminal lines (downline). Parameter

variations for PAD access transforms are governed by the

CCITT X.28 and X.29 protocols.

Level 2 of the X.25 TIP provides the NPU's interface to the

PDN for transferring information (level 2 is assisted by the

NPU's multiplex subsystem).

• 2 - 3 0 60471400 G

S&^S

0m*s.

Level 3 of the X.25 TIP provides the NPU's interface to the

PDN for multiplexing several logical channels through a

single, physical level 2 interconnection.

| Table 2-7 summarizes the data transfer characteristics

between terminals and the public data network devices and

the X.25 TD? in the NPU.

The normal mode for the subTIP is conversion to/from IVT

format. However, transparent mode is supported on both

input and output.

X.25 Input Sequence

Messages originate in a TTY-type terminal as an ASCD

character string preceded by a header and followed by a

trailer. A message is transmitted asynchronously, one

character at a time in bit-serial format, over a voice-grade

line. The PDN's PAD access collects the characters in

line-related ^virtual channel) packets. When a packet is

ﬁlled or the end-of-message signal is encountered, the

packet is released for transmission through the PDN.

The PDN frames the data for transmission to the NPU. A

single frame has data for only one virtual channel. After a

frame is given some control information and a

redundancy-check ﬁeld, the frame is dispatched to the

NPU over a high-speed, synchronous line. Transmission

over the link is in bit-serial format.

The receiving NPU's level 2 module reassembles the

incoming data into bit-parallel format, checks the frames

for transmission accuracy, discards the frame ﬁelds, and

directs the data to the level 3 module.

The level 3 module controls the packet level protocol; it

discards the packet control ﬁelds and sends the data to the

subTIP. At this time the data is associated with a speciﬁc

virtual channel.

The subTIP reformats the data into blocks (the terminal's

header and trailer are discarded to meet IVT

requirements). Then the terminal-related blocks are passed

to the block interface package (BIP) for ﬁnal formatting as

IVT blocks. IVT blocks are transmitted to the host through

the HIP.

X.25 Output Sequence

On output, the subTIP receives r/T blocks from the BIP.

The subTD? performs the format conversion necessary to

place the data in ASCD terminal format. This includes

generation of the terminal's header and trailer, as well as

the format changes which supply the proper line length and

number of lines per page. A page-wait capability is

supplied for terminals with displays. The subTIP repacks

the ASCII characters into data blocks. Data blocks are

sent to the packet level (3) of the TIP.

The packet level module maintains queues of packets.

When the frame level TD? needs more information blocks, it

requests them of the packet level. The packet level

responds by sending a set of information blocks from a

single packet queue.

The frame level (2) places the information blocks into

frames. Appropriate control and redundancy checking logic

is attached to the frame so that the PDN can check the

data for accuracy. Frames are sent continuously to the

PDN on the high-speed synchronous line. Copies of frames

TABLE 2-7. X.25/PAD TIP AND PDN

TRANSFER CHARACTERISTICS

TERMINAL

Asynchronous lines

ASCII code set

Dial-in or dedicated lines

Single character transfers to/from PAD

access in bit-serial format

Logical line sized message

PAD ACCESS IN PDN

Packet disassembly downline

Downline routing to individual terminals as

a bit-serial character stream

Packet assembly upline

PUBLIC DATA NETWORK

Network routing

Interface to level

NPU's X.25 TIP

2 and level 3 of the

X.25 TIP FRAME LEVEL

Link synchronization and maintenance

Frame formation downline (information from

level 3 placed in frames; all information

in a frame from one virtual channel)

Downline frame retransmission as necessary

Frame checking upline

Discards frame ﬁelds upline (passes infor

mation to level 3 TIP)

X.25 TIP PACKET LEVEL

Packet queues maintained downline (one

queue for each virtual channel)

Passes groups of packets as information

queues to frame level on request (a group

consists of packets selected on a strict

rotational basis from a single queue)

Packet queues maintained upline (one queue

for each virtual channel)

Requests retransmission of missing packets

upline

Supplies data to subTIP upline (the data

consists of one or more packets with the

packet header removed)

PAD SUBTIP

IVT block formation upline (conversion to

host format)

IVT blocks passed to BIP for transmission

to host

Conversion from IVT block format downline

to terminal format

Terminal formatted data placed in downline

data blocks

Blocks passed to packet level downline

(downline data blocks passed to level 3 are

sized to ﬁt packet rules)

are retained so that if errors occur during transmission,

frames can be retransmitted. Acknowledged frames are

discarded.

60471400 G 2-31

The PDN checks frame accuracy and requests retrans

mission if necessary. The PDN routes the data to the

appropriate PAD access, which disassembles the data and

sends the messages to the destination terminals one ASCII

character at a time.

Supported Terminal Classes

The X.25/PAD subTIP supports the following terminal

classes shown in table 2-8. Only the ASCD mode of these

terminals is supported.

TABLE 2-8. X.25/PAD SUBTIP TERMINAL CLASSES

Class Identiﬁer Characteristics

Teletype M33,

M35, M37, M38

CDC 713-10

Teletype M40

Hazeltine 2000

CDC LIAT 751,

752, 756

Tektronix 4014

Typewriter input,

hard copy print

output

Keyboard input;

scrolling display

output

Keyboard input;

scrolling display

output

Keyboard input;

scrolling display

output

Keyboard input;

scrolling display

output

Keyboard input;

scrolling display

output

Transparent Mode

The X.25 TIP allows transparent input and output.

Transparent input mode can be commanded either from the

terminal or from the host; transparent output mode is

selected by the application program. In either direction,

transparent mode terminates at the end of the message.

All data following the start of transparent mode are

considered to be transparent characters; however, the

subTTP scans all characters to detect the transparent

delimiter (this is often chosen to be a carriage return).

Upon detecting the transparent delimiter, the subTIP

returns to normal mode.

During output, the Tn? waits for a page-turn signal at the

end of the transparent message if page-wait mode is

selected.

Autoinput

If the downline message speciﬁes autoinput, the subTIP

saves the ﬁrst 20 characters of the output. When the

requested input arrives, the subTIP appends the input to the

saved data up to the length of one logical line, and

transmits the composite message to the host.

2-32

Parity

On input, character parity is carried in the ASCII character

as far as the subTIP. The subTD? ignores parity, but it

strips the parity bit from the character before releasing

the block to the host. Parity is not stripped from

transparent input if the parity selection is none (PA=N).

On output, parity actions are taken as shown in table 2-9.

TABLE 2-9. PARITY ACTIONS

Parity

Type Mode TIP Action

odd transparent supplies correct parity

odd normal supplies correct parity

even transparent supplies correct parity

even normal supplies correct parity

zero transparent sets parity to zero

zero normal se ts pa ri ty to zero

none transparent sends any existing parity

none normal se ts pa ri ty to zero

Typeahead Input from the Terminal

The CCITT X.3 standard does not specify typeahead;

therefore the X.25 TIP cannot guarantee typeahead. Some

PDNs may provide support typeahead as an option. The

X.25 TIP does not exclude the use of typeahead.

Block Mode

Supporting block-mode terminals is largely determined by

the PAD access. This includes deﬁnition of the

block-forwarding signal and the input device's ﬂow control

logic.

Fragmentation caused by packet assembly and the PAD

subTD^'s physical line processing makes reconstruction of a

single block-mode transmission from a terminal difﬁcult.

Since physical line boundaries are generally eliminated,

data may be lost if the message-forwarding signal is not

consistent throughout the CDC and packet switching

networks.

Backspacing from the Terminal

After the backspace character itself is discarded, it causes

the TIP to discard the previous character unless that

character was a part of the previous physical line. In that

case, the backspace character is ignored. Note that some

data characters are control codes without a graphic

representation, and other data characters move the cursor

on the display. For this reason, a physical line boundary

may not be obvious from the terminal.

60471400 G

y $ P ^ \ , Cancel Input

An input line can be cancelled by the terminal operator

entering the cancel character followed by the forwarding

character. The input line is discarded and a ♦DEL^

message is returned to the terminal. If part of the line has

already been sent to the host, a cancel messaage is sent to

the host.

Break Key Processing

Break processing occurs in the PAD access and in the PAD

subTff if the CCITT X.3 break option is chosen.

On the PAD access level, aD data queued for the terminal

and all subsequent data received from the PSN is

discarded. The PAD access notiﬁes the subTD?.

The subTIP suspends output until the next input is received

from the terminal. The PAD subTTP notiﬁes the PAD

access to allow subsequent output messages.

At the PAD subTIP, processing differs according to

whether the input following the break key is a user break or

not:

Command

TC - terminal class

PW - page width

PL - page length

PA - parity

CN - cancel

Bl - user break 1

B2 - user break 2

CT - control character

CI - CR idle count

LI - LF idle count

DL - transparent text

delimiter

IN - Input device

MS - message to net

work console

operator

PG - page-wait mode

Build-Time Selections

Allowable Value

1, 2, 5 - 8.

0-255

Z (zero), O (odd), E (even), N

(none)

Any keyboard character

0-255

Xhh where hh is the

character's hexadecimal value

X (transparent keyboard), K

(keyboard), XK (transparent

keyboard)

Any text up to 50 characters

in length

Y (yes), N (no)

• Not a user break: output to the terminal resumes

after input. Data discarded by the PAD access is

lost. Recovery of data is the responsibility of

higher level processes.

• User breaks: subTD? discards data and notifies the

host.

USER BREAKS

A user break can occur during any input message; it need

not follow an indication of a break key from the PAD

access.

Formatting on Output

For a given output message, formatting occurs on either a

preprint or a postprint basis, but never both.

Some formatting can occur as a result of the subTIP

converting format effectors to the appropriate number of

carriage returns, line feeds, escape characters, and the like.

For displays, the subTIP supplies the appropriate line

length, the number of lines on a display, and a pause at the

end of a display page. The terminal operator must answer

the pause by requesting a page turn. When this occurs, the

TD? sends the next full page of data.

For printers, the subTD? supplies the appropriate line

length, the number of lines on a page* and the proper

formatting to advance the form-feed mechanism to the top

of the next page.

At the time the user subscribes to the public data network,

he purchases certain interface options. In several cases,

these options effect the network deﬁnition language (NDL)

selections required by the NOS network. Table 2-10 deﬁnes

these parameters and gives the recommended settings for

use with the NOS network.

MESSAGE PRIORITIES AND

INPUT REGULATION

Messages are deﬁned to be high or low priority as a function

of the type of terminal which handles the message.

Regulation of messages is provided because all messages

require buffer space, and it is possible that combined peak

load demands from terminals, from the host, and from

neighboring NPUs (if any) may require more buffers than the

NPU can assign.

To prevent NPU stoppage for lack of buffers, the NPU is

allowed to reject input messages on the basis of priority or

because the channel seeking to input the messages already

has its maximum share of buffers assigned. For terminals

which are polled for input, regulation is handled indirectly:

the NPU does not poll the terminals until more buffers are

available. As current messages are processed and output,

more buffers become available and the regulation level can

change to accept message types previously rejected. Two

types of regulation are provided:

• Input message regulations: Varying criteria apply

according to the message source: host, neighboring

NPU, or terminal.

• Logical link regulation: Varying criteria apply

according to trafﬁc direction: upline or downline.

IVT Commands

The user can alter any of the IVT parameters shown below

at the terminal. These altered values remain a part of the

TIP's processing until changed from the terminal, or by a

host program. When the NPU is stopped and restarted, the

default rvT parameters are again used.

MESSAGE PRIORITIES

Three levels of message priority are deﬁned for CCP:

• Service message traffic (priority 0): This level

handles much of the node-to-node command/reply/

status information.

60471400 G 2-33

TABLE 2-10. CCITT PAD PARAMETERS AND RECOMMENDED SETTINGS

Parameter/

Values Description Recommended

Setting Cautions

Escape from data transfer (DLE)

DLE is treated as data character

DLE is a PAD control character

Any Setting = 1 allows the terminal user to

change other PAD parameters. However,

it eliminates the DLE character as a

val i d i n put c har a cte r.

Echo character to terminal

No echo

Echo

Any

126

Select data forwarding signal

No data forwarding signal

Carriage return

Any ASCII character in the range

0-31

The data forwarding signal for the PAD

subTIP should be the same as the data

for war din g sig nal f or the I VT. IVT

requires CR. Other settings cause

unnecessary packets and lost data.

1-255

Selecting idle timer delay

No timer

Time in l/20th second increments

Use of the PAD timer as a data forward

ing signal can be supported for line or

block mode terminals. Nonzero values

can be used in this fashion.

Ancillary device control

PAD does not supply X-ON or X-OFF

PAD generates X-ON and X-OFF

Any

PAD service signal suppression

No service signals

Service signals

Any

Selecting a terminal break signal

No break signals

PAD sends interrupt packet to NPU

PAD sends reset packet to NPU

BREAK replaces DLE

PAD sends interrupt packet to

NPU, clears terminal's output

queues, and sets parameter 8 to 1

21 The PAD subTIP uses the BREAK key to

interrupt output. The PAD sends a

break-indication PAD message to stop

output. Any other setting of this

parameter does not stop output, but

does not cause any other problems.

Discard output

Don't discard

Discard

Parameter is set to 1 by pressing BREAK

key if parameter 7 is 21. PAD subTIP

resets to 0 when it detects the break

condition.

1-255

Padding characters after a CR

None

Number of padding characters used

PAD subTIP supplies number of padding

characters according to the terminal

class (see appendix C, CCP System Pro

grammer's Reference Manual). Selection

of this parameter is unnecessary but

not detrimental. The IVT padding can

also be suppressed.

1-255

Line folding after a CR

None

Number of characters per line

PAD subTIP provides line folding and

screen and page formatting based on

the IVT page width (PW) parameter.

Additional line folding by the PAD

parameter can cause double spacing and

page or screen overﬂow.

Transmission rate (bps) of X.25

controller

110

300

1200

600

150

200

Any

2-34 60471400 G

TABLE 2-10. CCITT PAD PARAMETERS AND RECOMMENDED SETTINGS (Contd)

Parameter/

Values Description Recommended

Setting Cautions

12 Controller support of PAD ﬂow

control

Doesn't use X-ON and X-OFF for

ﬂow control

Uses X-ON and X-OFF for ﬂow

control

Any

NOTE

The PAD subTIP does not require that the PAD access support recommendation X.28. In general, it is not

necessary for the user to change the references for normal operation of an asynchronous terminal when

connected to the CDC network. Similarly, the PAD subTIP does not require supporting recommendation X.29.

The PAD references are not checked for compatibility, nor are they changed as a result of any command or

data. However, upon receipt of a break indication PAD message, the existence of PAD reference 7 and 8 is

assumed. Further, the X.29 set PAD parameters message is assumed to reset PAD reference 8 to allow

subsequent output. If PAD reference 7 is not set to 21, then support of X.29 is not required of the PAD.

High-level (priority 1): This level is intended for

messages associated with the interactive type of

terminal. The size of the message is normally

small but the message is quickly processed so that

no processing delay is visible to the terminal user.

Low-level (priority 2): This level is intended for

messages associated with batch-type terminals.

The size of the message is large (often a thousand

bytes or more) but since there is no operator

interaction required, a small delay in message

processing is acceptable. The actual assignment of

priorities by terminals is an installation time

function.

INPUT REGULATION

Four states of regulation are available to correspond to the

three message priorities. Table 2-11 indicates the type of

messages which are rejected during each state of regulation.

HOST INTERFACE REGULATION

Regulation applies to the high-speed DMA channel of the

coupler. The PPU separates its output data into three

queues:

• service message queue (highest priority)

• high-priority queue

• low-priority queue

Prior to outputting data to the NPU across the coupler, the

PPU sets the orderword which informs the NPU of the type

and length of the next message. The NPU returns status

information indicating acceptance or rejection of the

message based on the NPU's current regulation state.

• NOREG: All host output messages are accepted.

• STPLOW: Messages from the low-priority queue

are rejected.

o STPALL: Messages from the low- and high-priority

queues are rejected.

• ALERT: No messages are accepted from the host.

TRUNK INTERFACE REGULATION

The input frame (see LIP description in the CCP 3 System

Programmer's Reference Manual) from the sending NPU

can contain low-priority, high-priority, or service message

information, or combinations of priorities. Therefore, all

frames are accepted until the ALERT state occurs. Then

all frames are rejected. The sending NPU periodically

attempts to retransmit the rejected frame. If the ALERT

causes more than n rejections (n is an installation-time

parameter selection), the sending NPU declares the trunk

inoperative.

TERMINAL INTERFACE REGULATION

Prior to inviting new input from a terminal, the NPU

examines its buffer state. For high-priority terminals,

STPALL and ALERT stop the terminal's ability to input

messages. For low-priority terminals, STPLOW, STPALL

and ALERT stop the terminal (if not already stopped).

Either polling stops (Mode 4 terminals), request for input is

denied (HASP terminals), or input will be discarded as long

as the conditions for stop exist (Async terminals). The

appropriate TD? for any interactive (console-type) terminal

generates an input-stopped message for the terminal.

When the condition for stoppage disappears (NOREG for

low, STPLOW or NOREG for high-priority), input messages

are again accepted. The appropriate TIP generates an

input-resumed message to all interactive terminals that

received the input stopped message.

During the period of stopped input, uncontrolled interactive

terminals (Async TIP) may send input to the NPU. The

NPU discards this input and sends an input discarded

message to the terminal. Since NPU trafﬁc load is

variable, buffer availability may improve after the NPU

sends some of its output data. This may lower the

60471400 G 2-35

TABLE 2-11. REGULATION

Regulation

Level State

NOREG

STPLOW

STPALL

ALERT

Priorities

Accepted

0, 1, 2

0, 1

NONE

Remarks

Sufﬁcient buffers are available for all inputs. No regulation is

necessary. This regulation applies to host and terminals.

Buffers are low. NPU rejects all low priority message blocks,

regulation applies to host and terminals. This

Buffers are critically low. Both low and high priority message blocks

are rejected but service messages are accepted. This regulation

applies to host and terminals.

Buffers are so alarmingly low that any input message blocks could

cause the NPU to run out of buffers and therefore to stop. All input

blocks are rejected. This regulation applies to host, trunks, and

terminals.

regulation level so that previously stopped input can be

restarted. This in turn may quickly lower the buffer

availability, raise the regulation level, and therefore cause

the terminals to stop again. Note, however, that the buffer

state is examined only prior to inviting new input from a

terminal. Because of this, heavy data trafﬁc may cause

oscillation of the buffer state, causing frequent start-stop

terminal input sequences, especially for low-priority data.

Since trafﬁc, especiaUy high-speed batch trafﬁc, is

capable of saturating an NPU faster than interactive

trafﬁc, low priority (which is regulated ﬁrst), should be

assigned to terminals featuring large blocks and/or

high-speed capability. Interactive terminals, on the other

hand, should have high priority assigned, because a high

frequency of input stopped and input resumed messages

could have an irritating effect on the terminal user.

LOGICAL LINK REGULATION

Logical link (LL) regulation controls data input from

remote NPUs although it also operates in systems which

have no remote NPUs. Prior to any logical connection

assignment, logical links are created for any unique

physical path between the host and terminal node (see

ﬁgure 2-6). CS in the host distributes connection

assignments between the operational logical links to level

the trafﬁc load in the network.

Since LL regulation generaUy affects remote data sources,

there is a round-trip delay until such a regulation becomes

effective. To compensate for this, LL regulation occurs

prior to NPU input regulation for a given regulation level

as shown in ﬁgure 2-7. The LL regulation logic is executed

periodically, rather than as a function of TIP's checking

input trafﬁc prior to inviting new input trafﬁc (see NPU

input regulation, described previously).

Upline Data

Regulation for LLs is accomplished as a function of the

origin of the problem:

• Host interface: The host usually does not regulate

its input. The local NPU has a single output queue

to the coupler. It can happen (rarely) that the host

does not take that input.

• NPU buffers: The local NPU, which provides

transient storage for the LL data, regulates upline

LL data streams according to its own buffer

availability.

For remote NPUs, a trunk regulation level is sent to the

terminal node whenever necessary. The trunk regulation

level is sent initiaUy with the CLR-element of the trunk

protocol. Subsequent trunk regulations are sent with the

REGL-element.

The following trunk regulation levels are sent by the local

NPU to the remote node as a function of buffer

availability: NOREG, no regulation; STPLOW, stop

low-priority data; STPALL, stop all data.

• Coupler failure: If the local NPU detects a coupler

failure, it generates an ALERT-LL regulation

which is sent to the terminal node.

• Trunk failure: If the local NPU detects a trunk

failure, it sets the trunk regulation level to ALERT

and the trunk becomes inoperative. This action is

the same as if an ALERT LL occurred because of a

coupler failure.

• Remote NPU buffers: The remote NPU node has

its own buffers independent of those in the local

NPU.

The terminal node has two regulation levels that have to be

examined prior to inviting new input from a terminal:

• the terminal node's own buffer state (affects aU

terminals on the NPU)

• the LL regulation level (affects all terminals on

that LL)

The minimum of both regulation levels is used to determine

whether terminal input has to be stopped or restarted.

The ALERT level on the LL regulation indicates that a link

to the host has been broken, so in this case the terminal

node wiU generate the message HOST UNAVAILABLE to all I

interactive terminals on that LL. The ALERT level in the

terminal node's buffer state prompts only the message

INPUT STOPPED, which is probably a transient situation,

whereas the message HOST UNAVAILABLE is a unique I

indication that either the host is down, or the link to the

host has been broken.

^z^s.

^*^y

2-36 60471400 G

NS NODE

CS NODE

COUPLER

NODE

TERMINAL

NODE

HOST COUPLER LOCAL NPU REMOTE

NPU

Figure 2-6. Sample Logical Link Connections (Shown for Local and Remote NPUs)

BUFFER

AVAILABILITY

THRESHOLD

LEVELS

NOREG "

NOREG

STPLOW

STPALL

LL REGULATION

THRESHOLDS

ALERT

NPU INPUT

REGULATION

THRESHOLDS

NOTE: ALERT REGULATION

IS GOVERNED ONLY BY

COUPLER FAILURE FOR

LL REGULATION.

Figure 2-7. Buffer Availability Threshold

Levels for Regulation

Downline Data

Again, regulation action depends on the origin of the

problem.

• Host interface: The host monitors the received LL

regulation level prior to output on that LL. If

STPALL regulation is in effect on that LL, all

output for that LL is stopped. If a STPLOW

regulation is in effect, low-priority output is

stopped by the host. All output is sent to the

terminal node if a NOREG state exists.

In the ALERT case, the LL has failed and all logical

connections are broken by the local NPU.

• Local NPU buffers: The local NPU which receives

an REGL message over the logical link converts it

to an LL-Status SM. This SM is sent to the NS in

the host.

• Coupler failure: This is handled by the deadman

timer in the NPU and a similar timer in the host.

• Trunk failure: When the local NPU detects a trunk

failure, an LL-Status SM is sent to NS in the host.

The LL-Status SM indicates the failure of the LL.

The LL regulation level is set to ALERT. The host

receives an ALERT-LL regulation only in case of

LL failure.

• Remote NPU node: Since the remote NPU node is

the receiver of downline data, it is the source of

LL regulation for that data. As the host is the data

source, it is informed about regulation of its output.

The remote NPU node's buffer availability determines the

LL regulation level. This level is reported initially from

the local NPU with the PRST-response to the CLR; it is

reported subsequently by the REGL-element of the

LL-protocol.

The foUowing LL regulations are sent to the local NPU

according to the terminal node's buffer availability:

• NOREG - no regulation

• STPLOW - stop low-priority data

• STPALL - stop all data

60471400 G 2-37

Jptf££3y

INITIALIZING THE NPU

A three-step process makes each NPU into a fully

operational network node. These steps are:

• Dumping the NPU to the host (This is an optional

but usual procedure. A host applications program,

network dump analyzer (NDA), can be executed

via IAF to output the dump in a standard format

for later analysis.)

• Loading the NPU from the host (A special overlay

loading capability is available for on-line

diagnostics if these are a part of the system.

These diagnostics are not downline-loaded from

the host until called.)

• Initializing the NPU by configuring the network

logical links, lines and terminals that have

physical connections to this NPU

The host normally attempts to load/dump an NPU only if

the NPU fails or if the network operator speciﬁcally

requests a load. (Note that the host itself may fail; the

NPU is reloaded when the host comes back on-line.) In the

case of a failure or suspected failure, the host ﬁrst dumps

the NPU contents. The NPU is then loaded. If the ﬁrst

attempt to load the NPU fails, no further dumps are taken.

Failure of a local NPU is always detected by the host PPU

channel coupler driver. Upon detecting a failure condition

or upon receiving a Force-Load SM (which results from

the operator's load request), the NPU stops servicing the

channel coupler, the PPU is then able to detect the NPU

failure by a timeout of the protocol over the channel

coupler.

The load/dump process varies with the type and location

of the failed NPU. NPUs that are local*to the host are

loaded and dumped via the CYBER Coupler. NPUs are

loaded and dumped using a downline procedure.

When a remote NPU fails, the deadman timer is

activated. A primitive load/dump program is read into

the NPU from a cassette, and that bootstrap program

starts execution. The failed NPU establishes contact with

a neighbor NPU, which is itself a local NPU to the host.

The neighbor NPU communicates with the failed NPU

using a restricted set of the communications protocol

during this load/dump procedure. From this point

forward, the load/dump procedure is controlled by the

host.

LOAD/DUMP PHASES FOR LOCAL NPUs

Both load and dump operations for a 2551 are multiphase

and are shown in table 3-1.

LOCAL NPU LOADING

Any NPU connected to the host is a local NPU and is

loaded directly over a channel coupler by a PPU.

Micromemory (RAM) is always loaded before main

memory.

TABLE 3-1. LOAD/DUMP PHASES

Operation 2551

Dump 1. Dumps main memory

2. Loads main memory to host with

small program to:

• read file 1 registers

• checksum the RAM

3. Dumps results of program to

host

Load 1. Loads RAM contents into main

memory. Loads and executes

programs to load RAM.

2. Loads main memory

Micromemory cannot be directly loaded by the PPU; it is

loaded only by a program executing in the NPU. The PPU

loads (in a manner described below) a special micro-

memory loading program into the NPU main memory and

causes the program to be executed. The NPU then loads

its own micromemory and issues an idle response to the

PPU.

Main memory is written directly by the PPU to the NPU.

The NPU ﬁrst speciﬁes a start location by writing

memory addresses zero and one. The PPU then performs

successive data transfers to the NPU, re-reading each

area and comparing it word for word to ensure a correct

transfer. When loading is completed, the PPU issues a

start-NPU function. The NPU executes the program just

loaded and responds to the PPU with an idle response. If

there is no idle response, the NPU has failed.

Load File Format

Typically, NPU operating programs and tables are

formatted into a load ﬁle that is resident in the mass

storage of the host. To start NPU operation, that load

ﬁle (containing both the main memory-resident programs

and writable micromemory-resident programs) is trans

ferred (loaded) into the NPU.

The CCP load ﬁle contains all programs and tables except

line control blocks and terminal control blocks. Since the

load ﬁle deﬁnes a contiguous space in main memory, the

maximum number of line control blocks that can be

conﬁgured is ﬁxed. Terminal control blocks, however, are

built in dynamically acquired space and, therefore, are not

similarly limited.

The format of a load ﬁle record includes a preﬁx made up

of 15 60-bit words, a header that is a single 60-bit word,

one or more blocks (each having a maximum of 120 16-bit

words), and an end-of-record.

60471400 G 3-1

Figure 3-1 gives the typical load ﬁle format. A complete

I description is given in the Cross Link Loader Reference

Manual.

LOCAL NPU DUMPING, 2551 NPU

As noted previously, 2551 dumps consist of a main

memory image, ﬁle register image, and a ﬁrmware

checksum. The program which loads the ﬁle registers and

makes the checksum is in the main memory at the time

the latter two images are saved, so that program is also

dumped. Coupler registers are saved by the host and are

also dumped.

To transfer (dump) information from the NPU to the host,

the host executes the following procedure:

The host reads the three coupler registers (coupler

status register, NPU status register, and order-

word register), and retains these values for

incorporation into the register dump record.

The host builds the dump header record (Record 1)

containing the channel and equipment number of

the coupler, the date, and the time.

The host reads the entire NPU main memory

(starting at address zero) and formats the data

into blocks containing up to 120 16-bit words

each, with the entire group of blocks thus

constructed comprising the main memory dump

record (Record 2) of the dump ﬁle.

The host loads a dump bootstrap program into the

NPU main memory starting at address zero and

causes the program to be executed. This program

overwrites a portion of the micromemory with a

micromemory dump routine that generates a

16-bit micromemory checksum. The dump

bootstrap program then copies the 2551 File 1

registers, writes the value 8 (decimal) into the

NPU status register of the coupler (to indicate

ready for dump), and halts.

5. The host then again reads the NPU main memory

and formats the register dump record.

Format of the 2551 dump is shown in ﬁgure 3-2. Format

of the various types of words used in the dump are shown

in ﬁgure 3-3.

Format of the dump as processed and output by the host

| NDA program is given in appendix B. A sample dump is

shown in appendix B.

REMOTE NPU LOADING

NPUs which are not coupled to the host computer (remote

NPUs) are downline loaded from the host through a local

NPU (neighbor NPU). The failed remote NPU and its

neighbor must have a trunk between them that is

operational. The sequence of events necessary to dump

and then load the failed NPU are as follows:

1. The remote NPU sends a load request to its

neighbor NPU (this is the request-initialization

mode, RIM-element of the CDCCP protocol).

2. The LIP in the neighbor NPU sends a load-request

service message (SM) to the network supervisor

(NS) in the host. Format of the load-request SM

is:

Link/block

headers PFC

=01 SFC

=00 NODE

Primary and

secondary

function codes.

Identiﬁes neighbor NPU

Port of line (trunk) which neighbor

NPU uses for loading remote NPU-

3. NS responds by loading an overlay program into

the neighbor NPU's overlay area.

4. NS sends an overlay-data-clear SM to start the

load/dump process. Format of the message is:

Link/block

headers PFC

=05 SFC

=00 Overlay

Identiﬁes overlay segment

address in neighbor NPU —

Clear ﬂag

The dump phase is commanded by the NS. The

dump is handled in the neighbor NPU by the

overlay program received from the host. Blocks

of remote NPU main memory are transferred until

the dump is completed. This dump process is

described in detail under Remote NPU Dumping.

After the dump is completed, the load-remote-

NPU phase starts.

For a load phase of the multiphase dump/load

process, NS starts sending load commands to the

overlay in the neighbor NPU. The load command

contains an address and one or more words of

object code to be loaded into the remote NPU.

The load commands are sent between the NPUs in

batches with an acknowledgment being required

from the overlay for each batch of commands

successfully executed in the remote NPU. NS in

the host sets the response count ﬁeld of the last

command of each batch to the batch value. The

overlay acknowledges the batch complete when

the number of commands speciﬁed has been

processed.

NS continues to send batches of load commands

from the host until the load of the remote NPU is

completed. It is an NS responsibility to restrict

the number of load commands outstanding to a

level which avoids overloading the network by

regulating trafﬁc in the neighbor NPU while

continuing the load process in the remote NPU at

a reasonable rate.

When NS receives an acknowledgment for all load

commands, the command is sent to the overlay in

the neighbor NPU. The command is passed to the

remote NPU. If this is the last load phase of the

multiphase load/dump, the remote NPU enters its

conﬁguration procedure and attains operational

status.

/A^^\

3-2 60471400 G

PREFIX

WORD

IN DISPLAY CODE

59 48 4 7 3 6 3 5 2 4 2 3 1 8 1 7 0

7700 0016 BINARY ZERO FILL

DECK NAME 7777 BINARY ZERO FILL

DATE

TIME

OPERATING SYSTEM NAME OPERATING SYSTEM VERSION

LANGUAGE PROCESSOR NAME LANGUAGE PROCESSOR VERSION

LANGUAGE PROCESSOR MOD. LEVEL BINARY ZERO FILL

BINARY ZERO FILL

LANGUAGE PROCESSOR INFORMATION

BINARY ZERO FILL

USER COMMENTS

BINARY ZERO FILL

VALUES ARE IN OCTAL NOTATION

GENERAL HEADER FOR ALL INPUT FILE RECORDS:

W O R D 5 9 4 4 4 3 4 2 4 0 3 9 35 34 28 27 24 23 22 12 11

WCOUNT HT NU PN

PR PD

NAME

MCOUNT

NAME COMMENTS

s COMMENTS '.

COMMENTS

WORD FIELO

WCOUNT

MCOUNT

NAME

1 N A M E

COMMENTS

2 TO 7 COMME NTS

MEMORY IMAGE RECORD

W O R D 5 9 5 6 5 5

MEANING

NUMBER OF 16-BIT WORDS IN THE FOLLOWING

MEMORY IMAGE RECORD

IF HT = 1. 2.4. OR ZERO

IF HT = 0

TRAILER RECORO FLAG

HEADER TYPE

0 * MEMORY RESIDENT HEADER

1 = OVERLAY AREA HEADER

2 • OVERLAY HEADER

4 ■-■ MEMORY IMAGE HEADER

NOT USED

PAGE NUMBER (NOT USED IF HT

PAGE REGISTER (FOR HT 1. 2. 4

PAGE DISPLACEMENT IFOR HT - 1.

MODULE COUNT (HT = 0 ONLY)

UPPER PART OF SIX 8-BIT CHARACTER NAME OF RECORD

LOWER PART OF NAME

FIRST OF COMMENT FIELO

COMMENT FIELD

44 43

ONLYI

2. 4 ONLY)

DATA 1 DATA 2 DATA 3 DATA 4

DATA ;

ZERO FILL AS NECESSARYzr

Figure 3-1. Load File Format

60471400 B 3-3

Record 1 Header

2Main Memory

Dump Bootstrap

Program

Number of words in

second dump

File 1 Registers

Firmware Checksum

and Coupler Registers

Main Memory

Address (NPU)

(hexadecimal)

0000

01FF

0200

0300

Loading is controlled by service messages, and must appear

to start from the remote NPU itself. This is accomplished

in one of two ways:

• Forced loading:

A command entered by the network operator

requests loading or disabling an NPU. This starts

the deadman timer in the remote NPU which forces

the NPU to an inoperative status so it can be

reloaded. Communication to the remote NPU

takes the form of a force-load SM. Format of the

message is:

rLink/block

headers PFC

=01

SFC

=01

No parameters are necesary. Source node is the

NS; destination node is the remote NPU to be

reloaded.

Figure 3-2. Format of 2551 Dump

HEADER FORMAT

5 9 5 4 5 3 4 8 47 42 41 36 35 30 29 24 2 3 1 8 17 12 11

CN EN BL

SBL

WHERE: CN = CHANNEL NUMBER (BINARY)

EN = EQUIPMENT NUMBER OF NPU COUPLER (BINARY)

H H = H O U R \

N N = M I N U T E J

S S = S E C O N D (

MM = MONTH / DISPLAY C0DE

D D = D A Y I

Y Y = Y E A R /

. = PERIOD CHARACTER

/ = SLASH CHARACTER

BL = BLANK FILL

MAIN MEMORY WORD FORMAT: AS SHOWN IN APPENDIX B. MAIN MEMORY WORDS

ARE EACH FOUR HEXADECIMAL DIGITS.

FILE REGISTERS FORMAT

59 24 23 20 19 1 2 1 1 8 7

UHW LHW

WHERE: UHW = UPPER HALF WORD (OR CHARACTER 1)

L H W = LO WE R H A LF W O R D ( O R C HA RA C T E R 2 )

Z = Z E R O

Figure 3-3. Format of Words in Dumps

3-4 60471400 G

Failure-initiated loading:

Each remote NPU is provided with a deadman

timer, which is reset periodically. If the timer

expires, the NPU has failed. A bootstrap program

loaded from a tape cassette starts the attempt to

reload the NPU. This program sends a request for

initialization over a trunk, using a nonsequenced

element of the CDCCP protocol. This request is

sent over the selected trunk for a time period and,

should no reply be received, the request is repeated

over a different trunk. The request is sent to

neighbor NPUs, in sequence, until a reply is

received. The NPU is programmed to receive the

load operation over the replying trunk. If the

loading does not commence after a predetermined

interval, the deadman timer is activated and the

NPU re-enters the request-initialization-mode

sequence.

When a neighbor NPU accepts the nonsequenced element and

calls its LIP to process the message, the MP generates a

load-request SM to the host which has the message source

format shown previously. Parameters for the message are

the neighbor node ID, and the port ID from the neighbor

NPU to the remote NPU.

Upon receipt of the load-request SM from the neighbor NPU,

NS in the host initiates the remote-NPU-load procedure if

that NPU is enabled. The load/dump overlay is installed in

the neighbor NPU that originated the load-request SM. As

each block is loaded, the overlay program sends an overlay

data response. Any error causes the procedure to restart

with the load-request SM.

The loading and initialization of the remote NPU proceeds

almost entirely under the control of a series of

overlay-data SMs. The overlay-data service message has

the basic form:

Link/block

headers

PFC

=05

SFC

=00 Overlay

ID OC 00 Data

Overlay code = 0, 1, 2, or 3

(where applicable)

The four variations speciﬁed by the overlay code are:

Code = 0: Dumps the remote NPU

Code = 1: Loads neighbor NPU

Code = 2 Starts neighbor NPU to execute the loaded

overlay (sends load information to remote

NPU over trunk)

Code = 3: Clear overlay. This recycles pointers in the

overlay to start a new loading attempt.

When a neighbor NPU detects an initialization request, it

sends a load-request SM (format as shown previously) to NS

requesting a load of the failed element. NR ﬁrst installs the

load/dump overlay in the neighbor NPU program using

overlay-program-block SMs in order to provide the addi

tional code necessary to perform the load of the failed NPU.

Format of the overlay-program-block SM is:

The overlay data is transmitted through the trunk to the

remote NPU. The LIP in the neighbor NPU processes the

data (programs) into frame format so that the data is

compatible to the CDCCP trunk protocol. The general

format of the protocol is:

Byte 3 thru.N-3 N 2 N I

F A C I CRC

F Frame ﬂag

A Trunk address

CControl

= 1 for remote NPU

= 0 for loca 1 NPU

RIM (17.. J request for initialization (from remote

NPU) lb

UA (73-ﬁ) unnumbered acknowledgment

UI(131ﬁ) unnumbered information

SIM (07.. J set initialization mode (from neighbor

NPU) 16

Information (allowed only on UI frame)

CRC Cyclic redundancy check

Data transmission and service messages use UI frames.

Link/blk

headers

PFC

=04

SFC

=00 BN LBN Overlay

ID Checksum

This block number

Last block number-

Words m to n of overlay

program for neighbor NPU ■

It should be noted that NS preempts an already existing

overlay in the NPU in order to execute the load operation.

Thus, a diagnostic overlay may be terminated to make room

for the NPU load overlay.

Parameters for the load-overlay-data SM are: overlay ID,

overlay code = 1, port from neighbor NPU to remote NPU,

block count, beginning address to store this block of data

in remote NPU, block checksum, and up to 105 words of

overlay data. The overlay program attempts to load each

block into the failed NPU using nonsequenced elements of

the CDCCP protocol. The program in the failed NPU

checksums and veriﬁes each block received and causes an

incorrectly received block to be retransmitted. Form of

the load command as it is transmitted over the trunk is:

Bvte

6 1 6 7 8 9 10 11 12 L-2 L-l

F A CPad Pad Load Addr Wordl Word2 Wordn CRC

Pad Zero byte

Loac iLoad ﬂag

60471400 G 3-5 |

Addr

Wordl

Wordn

Remote NPU word where ﬁrst word of data is

to be stored

) n consecutive words of program data to be

/ lo

loaded into remote NPU starting at ADDR

F, A, C, and CRC were deﬁned previously.

The load response, sent over the trunk is a UA frame (see

above) which has no I bytes.

Should a load operation be unsuccessful for any reason,

the failed NPU reenters the initialization request

sequence to restart the load process from the beginning.

After several unsuccessful attempts to load a failed NPU,

NS declares the NPU down.

Each load command which is received causes data to be

passed by the CDCCP protocol over the trunk and to be

installed in the remote NPU memory by the bootstrap

program. When the protocol acknowledgment is received

by the UP in the neighbor NPU, this is passed back to the

load overlay. If the load command contains a non-null

block count ﬁeld and the load overlay has processed that

many load commands, then a block acknowledgment is

sent to NS in the host. If a load command with a null

block count ﬁeld is received, if a block response has been

solicited, and if the block total has now been reached,

then a block acknowledgment is sent to NS. A block count

of 1 is used by NS after the failure of any block to clean

up loading parameters.

If the loading attempt fails, NS attempts to use the

overlay in the neighbor without reloading it. The overlay-

data SM clear command accomplishes this. Parameters

for this SM are: overlay ID, overlay code = 3, port/

subport number from neighbor NPU to remote NPU. No

data is associated with this SM. Receipt of this message

causes the neighbor NPU to clear the status and count

ﬁelds in the load overlay, and to return conditions to

initial overlay status.

After a successful loading sequence, NS is ready to start

the newly loaded remote NPU. This action is triggered by

NS receiving an acknowledgment for the last block. NS

sends an overlay-data SM start command to the neighbor

NPU overlay. Parameters for this command are: overlay

ID, overlay code = 2, and port from neighbor NPU to

remote NPU. No data is associated with this SM. This

causes the overlay program to send a start command to

the failed NPU using a nonsequenced element of the

CDCCP protocol as follows:

As a result of the overlay-data SM start command, CCP

calls several procedures to initialize and make operational

various NPU functions. These include the initialization of

software tables (speciﬁcally, the trunk control block,

which has a format identical to the line control block and

other data structures), the communications subsystem, and

local devices. An unsolicited-trunk-status SM response

indicates that the link protocol has been established.

OPSMON is given control and the NPU is fully operational.

The remote NPU is now ready for conﬁguration.

REMOTE NPU DUMPING

Before loading the remote NPU, NS normally attempts to

dump the unit. As the majority of load operations result

from a unit failure, this ensures that any relevant

diagnostic or debugging information is saved before the

unit is reloaded. In order to avoid redundant dumps,

however, NS inhibits the dump if the NPU has not been

operational since the last dump. This occurs, for example,

on the second and subsequent load attempts after the ﬁrst

load attempt has failed.

The remote NPU dump operation is a multiphase operation

that dumps the main memory, the ﬁle 1 registers, and a

micromemory checksum. As was described above under

the remote NPU loading process, a bootstrap program is

read into the remote unit from the tape cassette, and the

NS program in the host sends an overlay program to the

neighbor NPU to supervise the dump operation. The

overlay speciﬁes the area of the remote main memory to

be dumped. Then the dump proceeds in three steps:

Byte

0 1

The overlay in the neighbor NPU sends a dump

command over the trunk, specifying the ﬁrst

block (by address) to be dumped. The block must

be less than 256 bytes long. This size includes

overhead as well as data. The format of the

frame sending the dump message is:

6 7 8 9 10 11 12 13 14 15

F A C Pad Pad Dmp Addri Pad Addr2 CRC

F, A, C, Pad, CRC are as deﬁned for load operation

Dmp Dump code

Addri Starting address of the dump in remote NPU

Addr2 Ending address

0123 4 6 7

F A C Address Start CRC

Byte

The remote NPU replies with a UA frame containing no

I-bytes (see above). By means of these two messages the

LIP has established the trunk protocol.

If the attempt to establish the trunk protocol fails, the

neighbor NPU sends an unsolicited-trunk-status SM.

Program execution starts at the address found in bytes 0

and 1.

2. The remote NPU sends the memory block which

the neighbor NPU passes to the NS in the form of

an overlay data response SM (see appendix E).

The frame which is sent over the trunk containing

the dump data has the form:

0 1 2 3 4 8 9 10 . L-4 L-3 L-2 L-l L

Pad Dmp Addri •Vr

Wordl ... Wordn

«CRC

-Length of subblocks in bytes

3-6 60471400 G

j0m$S

3. Steps 1 and 2 are repeated, dumping all blocks of

the remote NPU main memory within the region

speciﬁed by the overlay in the neighbor NPU.

Then the loading process can begin.

The dumping operation is controlled by two types of SMs:

The overlay-data SM dump commands, and the overlay-

data SM dump response.

When NS is set to dump the remote NPU, it sends the

neighbor NPU a series of overlay-data SM dump com

mands. Format of the SM is:

Link/block

headers

PFC

=05

SFC

=00 Overlay

ID 00 00 00 00 Begin

Addr

End

Addr

Required parameters are: overlay ID, overlay code = 0,

port/subport number from the neighbor NPU to the

remote NPU, and beginning and ending addresses of the

remote NPU main memory to be dumped in this block. By

regulating the size of the blocks, the NS can meter the

amount of dump data from the remote NPU. Note that no

more than 105 main memory words can be dumped in any

one block.

Note that these overlay-data SMs include provisions to

load the bootstrap and to execute the bootstrap in order

to save ﬁles, registers, and micromemory checksum.

The neighbor NPU commands the data transfer by sending

an unnumbered information (UI) frame to the remote

NPU. This frame speciﬁes the block of core to be

dumped. The remote NPU replies with a UI frame

prefacing the requested words of data (main memory).

After the remote NPU responds with the block of data

requested, the neighbor NPU embeds this data in an

overlay-data SM dump response. Format of the response

Link/

block

hdrs

PFC

=05 SFC Overlay

ID 00 00 RC 00 Begin

Addr Data

Response code

Data words (1 - 105)

Parameters for this SM are: overlay ID, overlay code = 0,

port number from neighbor NPU to remote NPU, response

code, beginning address of the dump, and 1 to 105 words

of dumped main memory. Response code indicates suc

cess or failure of this dump block transmission.

CONFIGURING NPUs

After the NPU is loaded, the host conﬁgures the unit by

establishing all logical links and logical connections for

that NPU. A logical connection is the association of two

stations made by the assignment of a network logical

address. The network logical address is a set of three

numbers: two node IDs followed by a connection number.

The two node IDs represent the nodes at which each

station interfaces to the network. The order in which

they appear in the network logical address speciﬁes the

direction of the connection (the destination node

appearing ﬁrst, then the source node). The connection

number speciﬁes a full-duplex logical channel connecting

the stations. Connection number zero is reserved as a

permanent service channel for service message com

munications.

The set of logical connections which potentially exists

between stations supported by a node pair is referred to as

a logical link. A logical link must be explicitly established

before logical connections may be assigned to it. (The

service channel, which is designated as zero, is an

exception to this rule.)

The network supervisor (NS) program and the communi

cations supervisor (CS) program in the CYBER host are

responsible for the control of logical links and

connections, respectively, in the network. All logical

links and connections are explicitly conﬁgured,

reconﬁgured, and deleted by NS/CS use of network

service messages (SMs). Note that the conﬁguration is

part of the general scheme of making a network

operational. Reconﬁguration and deletion can occur at

any time while the network is running. All three

processes are described together in this section.

Conﬁguration proceeds in three stages:

• establishing logical links

• configuring logical lines

• connecting terminal over the lines

NS establishes all logical links which the current state of

the network permits. First NS notiﬁes CS of each logical

link to be established. The network also informs CS of the

initial logical link regulation level. CS conﬁgures the

lines or recovers the conﬁguration status of the lines,

depending upon NPU status. Whenever a line is reported

to CS as operational, CS conﬁgures the line and attempts

to connect each terminal on the line.

To connect the terminal, the line must be enabled. The

terminal is connected by the NPU building a terminal

control block (TCB) for the terminal. This process is

initiated in the NPU when CS dispatches a conﬁgure or

reconﬁgure-terminal SM. The message includes the CN

assigned by CS for the connection. When the conﬁgure or

reconﬁgure action has been performed, the block protocol

is initiated and the connection is in use. CS is informed of

the successful completion of the conﬁguration by a

normal response. NS is informed of an NPU entering this

active state by the arrival of an NPU-initialized SM (in

the case of restoring a failed NPU) or by the arrival of the

ﬁrst-trunk-status response SM (where the response

indicates the trunk is operational). The latter occurs

when an operational NPU rejoins the network.

60471400 G 3-7 |

/"*%

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FAILURE, RECOVERY, AND DIAGNOSTICS

Failure and recovery of CCP depends on a number of

factors:

• Host failure: If a host fails, the NPU and its

software must necessarily stop message processing.

o NPU failure: If an NPU fails, it must be reloaded

and reinitiated from the host. Off-line diagnostic

tests may be desirable during this period to help

identify the cause of failure.

• Logical link failure: Host failure was mentioned

above. Link CDCCP protocol failure leads to

higher and higher levels of regulation until message

trafﬁc ceases on the link.

• Line failure: Lines are disconnected and terminal

control blocks (TCBs) associated with the lines are

deleted.

• Terminal failure: Terminal status is reported and

message is discarded.

To aid recovery and to assure dependable network operations

that involve the CCP, three sets of diagnostic programs are

available.

• Inline diagnostics. These include CE error and

alarm messages, statistics messages, halt code

messages that specify the reason for an NPU

failure, and off-line dumps.

• Optional on-line diagnostic tests that allow check

ing of circuits to terminals. These aids are

available only if a network maintenance contract

is purchased.

• Off-line diagnostics. These hardware tests for

NPU circuits are described in detail in the Network

Processor Unit Hardware Maintenance Manual.

The diagnostic commands are summarized in appendix B.

60471400 D 4-1

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CODED CHARACTER DATA INPUT, OUTPUT, AND

CENTRAL MEMORY REPRESENTATION

><*\

/ g f c j y

This appendix describes the code and character sets used

by host computer operating system local batch device

drivers, magnetic tape drivers, and terminal

communication products. Some software products assume

that certain graphic or control characters are associated

with speciﬁc binary code values for collating or syntax

processing purposes. This appendix does not describe those

associations for all products.

All references within this manual to the ASCII character

set or the ASCII code set refer to the character set and

code set deﬁned in the American National Standard Code

for Information Interchange (ASCII, ANSI Standard

X3.4-1977). References in this manual to the ASCII

character set do not necessarily apply to the ASCII

code set.

CHARACTER SETS AND CODE SETS

A character set differs from a code set. A character set is

a set of graphic and/or control characters. A code set is a

set of codes used to represent each character within a

character set. Characters exist outside the computer

system and communication network; codes are received,

stored, retrieved, and transmitted within the computer

system and network.

GRAPHIC AND CONTROL CHARACTERS

A graphic character can be displayed at a terminal or

printed by a line printer. Examples of graphic characters

are the characters A through Z, a blank, and the digits 0

through 9. A control character initiates, modiﬁes, or stops

a control operation. An example of a control character is

the backspace character, which moves the terminal

carriage or cursor back one space. Although a control

character is not a graphic character, some terminals can

produce a graphic representation when they receive a

control character.

CODED AND BINARY CHARACTER

DATA

Character codes can be interpreted as coded character

data or as binary character data. Coded character data is

converted from one code set representation to another as

it enters or leaves the computer system; for example, data

received from a terminal or sent to a magnetic tape unit is

converted. Binary character data is not converted as it

enters or leaves the system. Character codes are not

converted when moved within the system; for example,

data transferred to or from mass storage is not converted.

The distinction between coded character data and binary

character data is important when reading or punching cards

and when reading or writing magnetic tape. Only coded

character data can be properly reproduced as characters on

a line printer. Only binary character data can properly

represent characters on a punched card when the data

cannot be stored as display code.

The distinction between binary character data and

characters represented by binary data (such as peripheral

equipment instruction codes) is also important. Only such

binary noncharacter data can properly reproduce

characters on a plotter.

FORMATTED AND UNFORMATTED

CHARACTER DATA

Character codes can be interpreted by a product as

formatted character data or as unformatted character

data. Formatted data can be stored or retrieved by a

product in the form of the codes described for coded

character data in the remainder of this appendix, or

formatted data can be altered to another form during

storage or retrieval; for example, 1 can be stored as a

character code or as an integer value. Treatment of

unformatted data by a product includes both coded

character data and binary character data as described in

this appendix.

NETWORK OPERATING SYSTEM

The Network Operating System (NOS) supports the

following character sets:

CDC graphic 64-character set

CDC graphic 63-character set

ASCII graphic 64-character set

ASCII graphic 63-character set

ASCII graphic 95-character set

ASCII 128-character graphic and control set

Each installation must select either a 64-character set or a

63-character set. The differences between the codes of a

63-character set and the codes of a 64-character set are

described under Character Set Anomalies. Any reference

in this appendix to a 64-character set implies either a 63-

or 64-character set unless otherwise stated.

To represent its six listed character sets in central

memory, NOS supports the following code sets:

• 6-bit display code

• 12-bit ASCII code

• 6/12-bit display code

The 6-bit display code is a set of 6-bit codes from OOg

to 778.

The 12-bit ASCII code is the ASCII 7-bit code (as deﬁned

by ANSI Standard X3.4-1977) right-justiﬁed in a 12-bit

byte. Assuming that the bits are numbered from the right

starting with 0, bits 0 through 6 contain the ASCII code,

bits 7 through 10 contain zeros, and bit 11 distinguishes the

12-bit ASCII OOOOg code from the end-of-line byte. The

12-bit codes are OOOlg through 01778 and 40008.

60471400 G A-l •

The 6/12-bit display code is a combination of 6-bit codes

and 12-bit codes. The 6-bit codes are 008 through 77s,

excluding 74g and 76g. (The interpretation of the

OOg and 63g codes is described under Character Set

Anomalies later in this appendix.) The 12-bit codes begin

with either 74g or 76g and are followed by a 6-bit

code. Thus, 74g and 76g are considered escape codes

and are never used as 6-bit codes within the 6/12-bit

display code set. The 12-bit codes are 7401g, 7402g,

7404g, 7407a, and 7601g through 7677g. All other

12-bit codes (74xx8 and 7600g) are undeﬁned.

CHARACTER SET ANOMALIES

The operating system input/output software and some

products interpret two codes differently when the

installation selects a 63-character set rather than a

64-character set. If an installation uses a 63-character

set, the colon graphic character is always represented by a

63g code, display code OOg is undeﬁned (it has no

associated graphic or punched card code), and the %

graphic does not exist.

If the installation uses a 64-character set, output of a

7404g 6/12-bit display code or a OOg display code

produces a colon. A colon can be input only as a 7404g

6/12-bit display code. The use of undeﬁned 6/12-bit

display codes in output ﬁles produces unpredictable results

and should be avoided.

Two consecutive OOg codes can be confused with an

end-of-line byte and should be avoided.

CHARACTER SET TABLES

The character set tables A-l and A-2 are designed so that

the user can ﬁnd the character represented by a code (such

as in a dump) or ﬁnd the code that represents a character.

To ﬁnd the character represented by a code, the user looks

up the code in the column listing the appropriate code set

and then ﬁnds the character on that line in the column

listing the appropriate character set. To ﬁnd the code that

represents a character, the user looks up the character and

then ﬁnds the code on the same line in the appropriate

column.

Conversational Terminal Users

Table A-l shows the character sets and code sets available

to an Interactive Facility (IAF) user at an ASCII code

terminal using an ASCII character set. Table A-9 (later in

this appendix) shows the octal and hexadecimal 7-bit ASCII

code for each ASCII character, and can be used to convert

codes from octal to hexadecimal. (Under NOS using

network product software, certain Terminal Interface

Program commands require speciﬁcation of an ASCII code.)

IAF Usage

When in normal time-sharing mode (speciﬁed by the IAF

NORMAL command), IAF assumes the ASCII graphic

64-character set is used and translates all input and output

to or from display code. When in ASCII time-sharing mode

(speciﬁed by the IAF ASCII command), IAF assumes the

ASCII 128-character set is used and translates all input and

output to or from 6/12-bit display code.

The IAF user can convert a 6/12-bit code ﬁle to a 12-bit

ASCII code ﬁle using the NOS FCOPY control statement.

The resulting 12-bit ASCII ﬁle can be routed to a line

printer but cannot be output through IAF.

IAF supports both character mode and transparent mode

transmissions through the network. These transmission

modes are described under Network Access Method

Terminal Transmission Code Sets in this appendix. IAF

treats character mode transmissions as coded character

data; IAF converts these transmissions to or from either

6-bit or 6/12-bit display code. IAF treats transparent

mode transmissions as binary character data; transparent

mode communication between IAF and ASCII terminals

using any parity setting occurs in the 12-bit ASCII code

shown in table A-l.

Local Batch Users

Table A-2 lists the CDC graphic 64-character set, the

ASCII graphic 64-character set, and the ASCII graphic

95-character set. This table also lists the code sets and

card keypunch codes (026 and 029) that represent the

characters.

The 64-character sets use display code as their code set;

the 95-character set uses 12-bit ASCII code. The

95-character set is composed of all the characters in the

ASCII 128-character set that can be printed at a line

printer (refer to Line Printer Output). Only 12-bit ASCII

code ﬁles can be printed using the ASCII graphic

95-character set. To print a 6/12-bit display code ﬁle

(usually created in IAF ASCII mode), the user must convert

the ﬁle to 12-bit ASCII code. To do this, the NOS FCOPY

control statement must be issued. The 95-character set is

represented by the 12-bit ASCII codes 0040g

through 0176g.

Line Printer Output

The batch character set printed depends on the print train

used on the line printer to which the ﬁle is sent. The

following are the print trains corresponding to each of the

batch character sets:

,*SSv

Character Set

CDC graphic 64-character set

ASCII graphic 64-character set

ASCII graphic 95-character set

Print Train

596-1

596-5

596-6

The characters of the default 596-1 print train are listed in

the table A-2 column labeled CDC Graphic (64-Character);

the 596-5 print train characters are listed in the table A-2

column labeled ASCII Graphic (64-Character); and the

596-6 print train characters are listed in the table A-2

column labeled ASCII Graphic (95-Character).

If a transmission error occurs during the printing of a line,

NOS prints the line again. The CDC graphic print train

prints a concatenation symbol (r*) in the ﬁrst printable

column of a line containing errors. The ASCII print trains

print an underline instead of the concatenation symbol.

If an unprintable character exists in a line (that is, a 12-bit

ASCII code outside of the range 0040g through 0176g),

the number sign (#) appears in the ﬁrst printable column of

a print line and a space replaces the unprintable character.

/ * S ^ V

A-2 60471400 G

^p\

Punched Card Input and Output

Under NOS, coded character data is exchanged with local

batch card readers or card punches according to the

translations shown in table A-2. As indicated in the table,

additional card keypunch codes are available for input of

the ASCII and CDC characters ]and[. The 95-character

set cannot be read or punched as coded character data.

Depending on an installation or deadstart option, NOS

assumes an input deck has been punched either in 026 or

029 keypunch code (regardless of the character set in use).

The alternate keypunch codes can be speciﬁed by a 26 or

29 punched in columns 79 and 80 of any 6/7/9 card or 7/8/9

card. The speciﬁed code translation remains in effect

throughout the job unless it is reset by speciﬁcation of the

alternate code translation on a subsequent 6/7/9 card or

7/8/9 card.

NOS keypunch code translation can also be changed by a

card containing a 5/7/9 punch in column 1. A blank (no

punch) in column 2 indicates 026 conversion mode; a

9 punch in column 2 indicates 029 conversion mode. The

conversion change remains in effect until another change

card is encountered or the job ends.

The 5/7/9 card also allows literal input when 4/5/6/7/8/9 is

punched in column 2. Literal input can be used to read

80-column binary character data within a punched card

deck of coded character data.

Literal cards are stored with each column in a 12-bit byte

(a row 12 punch is represented by a 1 in bit 11, row 11 by

bit 10, row 0 by bit 9, and rows 1 through 9 by bits 8

through 0 of the byte), 16 central memory words per card.

Literal input cards are read until a card identical to the

previous 5/7/9 card (4/5/6/7/8/9 in column 2) is read. The

next card can specify a new conversion mode.

Remote Batch Users

When card decks are read from remote batch devices, the

ability to select alternate keypunch code translations

depends upon the remote terminal equipment.

Remote batch terminal line printer, punched card, and

plotter character set support is described under Input Deck

Structure in the Remote Batch Facility (RBF) reference

manual. RBF supports only character mode transmission to

and from consoles through the network. Character mode is

described under Network Access Method Terminal

Transmission Code Sets in this appendix.

Because only 63 characters can be represented in 7-track

even parity, one of the 64 display codes is lost in

conversion to and from external BCD code. Figure A-l

shows the differences in conversion that depend on which

character set (63 or 64) the system uses. The ASCII

character for the speciﬁed character code is shown in

parentheses. The output arrow shows how the display code

changes when it is written on tape in external BCD. The

input arrow shows how the external BCD code changes

when the tape is read and converted to display code.

63-Character Set

Display Code External BCD Display Code

33(0)

63(:>

16(%)

Output 12(0)

12(0)

64-Character Set

Input

33(0)

Display Code

00(:)

33(0)

63(%)

External BCD

12(0)

Output 12(0)

16{%)

Input

Display Code

33(0)

63(%)

Figure A-l. Magnetic Tape Code Conversions

Tables A-3 and A-4 show the character set conversions for

nine-track tapes. Table A-3 lists the conversions to and

from 7-bit ASCII character code and 6-bit display code.

Table A-4 lists the conversions between 8-bit EBCDIC

character code and 6-bit display code. Table A-5 shows

the character set conversions between 6-bit external BCD

and 6-bit display code for seven-track tapes.

If a lowercase ASCII or EBCDIC code is read from a

9-track coded tape, it is converted to its uppercase 6-bit

display code equivalent. To read and write lowercase

ASCII or EBCDIC characters, the user must assign the tape

in binary mode and then convert the binary character data.

During binary character data transfers to or from 9-track

magnetic tape, the 7-bit ASCII codes shown in table A-3

are read or written unchanged; the 8-bit hexadecimal

EBCDIC codes shown in table A-4 also can be read or

written unchanged. ASCII and EBCDIC codes cannot be

read or written to 7-track magnetic tape as binary

character data.

Magnetic Tape Users

Coded character data to be copied from mass storage to

magnetic tape is assumed to be represented in display

code. NOS converts the data to external BCD code when

writing a coded 7-track tape and to ASCII or EBCDIC code

(as speciﬁed on the tape assignment statement) when

writing a coded 9-track tape.

Tables A-6 and A-7 list the magnetic tape codes and their

punch code equivalents on IBM host computers.

Two CDC utility products, FORM and the 8-Bit

Subroutines, can be used to convert to and from EBCDIC

data. Table A-7 contains the octal values of each EBCDIC

code right-justiﬁed in a 12-bit byte with zero ﬁll. This

12-bit EBCDIC code can also be produced using FORM and

the 8-Bit Subroutines.

60471400 G A-3 •

TABLE A-l. CONVERSATIONAL TERMINAL CHARACTER SETS

ASCII

Graphic

(64-Char

acter Set)

colon™

plus

- minus

* asterisk

/ slash

( I. paren.

) r. p a r e n .

$ dollar

= equal to

space

f comma

. period

tt number

r I. bracket

3 r. b ra c k et

X percent tt

" quote

__ underline

! exclam.

8 ampersand

1 apostrophe

? question

< less than

> g r t r . t h a n

3 comI. at

\ r e v. s l a n t

•** circumflex

; semi colo n

ASCII

Character

(128-Char-

acter Set)

+ plus

- minus

* asterisk

/ slash

(I. paren.

) r. paren.

$ dollar

= equal to

space

, comma

. period

tt number

r. I. bracket

3 r. b r a c k e t

X percenttt

" quote

_ underline

! exclam.

S ampersand

* apostrophe

? question

< less than

> grtr. than

\ rev. slant

; semi colo n

3 coml. at

Octal

6-Bit

Display

Code

oott

63tt

O c t a l

6/12-Bit

Display

Codet

63tt

7401

Octal

12-Bit

ASCII

Code

0101

0102

0103

0104

0105

0106

0107

0110

0111

0112

0113

0114

0115

0116

0117

0120

0121

0122

0123

0124

0125

0126

0127

0130

0131

0132

0060

0061

0062

0063

0064

0065

0066

0067

0070

0071

0053

0055

0052

0057

0050

0051

0044

0075

0040

0054

0056

0043

0133

0135

0045

0042

0137

0041

0046

0047

0077

0074

0076

0134

0073

0100

ASCII

Graphic

(64-Char

acter Set)

ASCII

Character

(128-Char-

acter Set)

**" circumﬂex

: colontt

grave accent

< left brace

| vert, line

> right brace

" tilde

NUL

SOH

STX

ETX

EOT

ENQ

ACK

BEL

DEL

DLE

DC1

DC2

DC3

DC4

NAK

SYN

ETB

CAN

SUB

ESC

Octal

6-Bit

Display

Code

Octal

6/12-Bit

Display

Codet

Octal

12-Bit

ASCII

Code

7402 0136

7404tt 0072

7407 0140

7601 0141

7602 0142

7603 0143

7604 0144

7605 0145

7606 0146

7607 1047

7610 0150

7611 0151

7612 0152

7613 0153

7614 0154

7615 0155

7616 0156

7617 0157

7620 0160

7621 0161

7622 0162

7623 0163

7624 0164

7625 0165

7626 0166

7627 0167

7630 0170

7631 0171

7632 0172

7633 0173

7634 0174

7635 0175

7636 0176

7640 4000

7641 0001

7642 0002

7643 0003

7644 0004

7645 0005

7646 0006

7647 0007

7650 0010

7651 0011

7652 0012

7653 0013

7654 0014

7655 0015

7656 0016

7657 0017

7637 0177

7660 0020

7661 0021

7662 0022

7663 0023

7664 0024

7665 0025

7666 0026

7667 0027

7670 0030

7671 0031

7672 0032

7673 0033

7674 0034

7675 0035

7676 0036

7677 0037

tGenerally available only on NOS, or through BASIC on NOS/BE.

ttThe interpretation of this character or code depends on its context. Refer to Character Set Anomalies in

the text.

• A - 4 60471400 G

^VCE^v

TABLE A-2. LOCAL BATCH DEVICE CHARACTER SETS

CDC ASCII ASCII Octal Octal Octal Card Keypunch Code

Graphic Graphic Graphic 6 - B i t 6/12-Bit 12-Bit

(64-Character (64-Character (95-Character Display Display ASCII 026 029

Set) Set) Set) Code Codet Code

: c o lon tt : colontt 00 tt 8-2 8-2

A A A 01 01 0101 12-1 12-1

BBB 02 02 0102 12-2 12-2

C C C 03 03 0103 12-3 12-3

D D D 04 04 0104 12-4 12-4

E E E 05 05 0105 12-5 12-5

F F F 06 06 0106 12-6 12-6

G G G07 07 0107 12-7 12-7

H H H 10 10 0110 12-8 12-8

I I I 11 11 0111 12-9 12-9

J J J 12 12 0112 11-1 11-1

KKK 13 13 0113 11-2 11-2

L L L 14 14 0114 11-3 11-3

M M M 15 15 0115 11- 4 11-4

N N N 16 16 0116 11-5 11-5

0 0 0 17 17 0117 11-6 11-6

P P P 20 20 0120 11-7 11-7

Q Q Q21 21 0121 11-8 11-8

R R R 22 22 0122 11-9 11-9

S S S 23 23 0123 0-2 0-2

T T T 24 24 0124 0-3 0-3

UUU25 25 0125 0-4 0-4

V V V 26 26 0126 0-5 0-5

w u u 27 27 0127 0-6 0-6

X X X 30 30 0130 0-7 0-7

Y Y Y 31 31 0131 0-8 0-8

Z Z Z 32 32 0132 0-9 0-9

0 0 0 33 33 0060

1 1 1 34 34 0061

22235 35 0062

3 3 3 36 36 0063

4 4 4 37 37 0064

5 5 5 40 40 0065

66 6 41 41 0066

777 42 42 0067

8 8 8 43 43 0070

9 9 9 44 44 0071

+ plus + plus + plus 45 45 0053 12 12-8-6

- minus - minus - minus 46 46 0055 11 11

* a s teri s k * a ste r i sk * a s teri s k 47 47 0052 11-8-4 11-8 -4

/ slash / sla sh / s la sh 50 50 0057 0-1 0-1

( lef t par en . ( l e ft p a ren. ( left paren. 51 51 0050 0-8-4 12-8-5

) right paren. ) right paren. ) right paren. 52 52 0051 12-8-4 11-8-5

$ d ol lar $ d o l l a r $ dol la r 53 53 0044 11-8-3 11-8-3

= equal to = equal to = equal to 54 54 0075 8-3 8-6

space space space 55 55 0040 no punch no punch

, comma , comma z comma 56 56 0054 0-8-3 0-8-3

. period . pe riod . period 57 57 0056 12-8-3 12-8-3

= equivalence ft number ft number 60 60 0043 0-8-6 8-3

C left bracket C- left bracket C I. bracket 61 61 0133 8-7 12-8-2

or 12-0nt

3 ri ght bra cke t 3 rig ht bra ck et 3 r. bracket 62 62 0135 0-8-2 11-8-2

or 11-0™t

% percent™ X percent™ % percent™ 63 63 0045 8-6 0-8-4

60471400 G A-5 •

TABLE A-2. LOCAL BATCH DEVICE CHARACTER SETS (Contd)

CDC

Graphic

(64-Character

Set)

* not equal

f*concat.

V togical OR

A logical AND

t superscript

i s u bscr i pt

< less than

> greater than

< less/equal

> greater/equal

-i logical NOT

; semicolon

ASCII

Graphic

(64-Character

Set)

" quote

__ underline

! exclamation

8 ampersand

1 apostrophe

? question

< less than

> greater than

3 commercial at

\ reverse slant

**• circumflex

; semicolon

ASCII

Graphic

(95-Character

Set)

" quote

_ underline

! exclamation

& ampersand

1 apostrophe

? question

< less than

> greater than

\ rev. slant

; semicolon

3 comI. at

**• circumflex

: colon™

* grave accent

< left brace

| vert, line

> right brace

" tilde

Octal

6-Bit

Display

Code

Generally available only on NOS, or through BASIC on NOS/BE.

Octal

6/12-Bit

Display

Codet

7401

7402

7404™

7407

7601

7602

7603

7604

7605

7606

7607

7610

7611

7612

7613

7614

7615

7616

7617

7620

7621

7622

7623

7624

7625

7626

7627

7630

7631

7632

7633

7634

7635

7636

Octal

12-Bit

ASCII

Code

0042

0137

0041

0046

0047

0077

0074

0076

0134

0073

0100

0136

0072

0140

0141

0142

0143

0144

0145

0146

0147

0150

0151

0152

0153

0154

0155

0156

0157

0160

0161

0162

0163

0164

0165

0166

0167

0170

0171

0172

0173

0174

0175

0176

Card Keypunch Code

026

8-4

0-8-5

11-0

0-8-7

11-8-5

11-8-6

12-0

11-8-7

8-5

12-8-5

12-8-6

12-8-7

029

8-7

0-8-5

12-8-7

8-5

0-8-7

12-8-4

0-8-6

8-4

0-8-2

11-8-7

11-8-6

ttt

The interpretation of this character or code depends on its context. Refer to Character Set Anomalies

in the text.

Available for input only, on NOS.

• A-6 60471400 G

TABLE A-3. ASCII 9-TRACK CODED TAPE CONVERSION

ASCII ASCII

Display Display

Code Character and Codet™ Code Character and Codettt

Conversiont Code Conversion™ Conversiont Code Conversion™

Code

(Hex) Char Code

(Hex) Char ASCII

Char

Code

(Octal)

Code

(Hex) Char Code

(Hex) Char ASCII

Char

Code

(Octal)

20 space 00 NUL space 55 40 60 74

21 7D 66 41 61 01

22 ii 02 STX 64 42 62 02

23 tt 03 ETX ft 60 43 63 03

24 04 EOT 53 44 64 04

25 05 ENQ 63 45 65 05

25 05 ENQ space 55 46 66 06

26 06 ACK 67 47 67 07

27 07 BEL 70 48 68 10

28 08 BS 51 49 69 11

29 09 HT 52 4A 6A 12

2A 0A LF 47 4B 68 13

2B 0B VT 45 4C 6C 14

2C 0C FF 56 4D 6D 15

2D 0D CR 46 4E 6E 16

2E 0E SO 57 4F 6F 17

2F OF SI 50 50 70 20

30 10 DLE 33 51 71 21

31 11 DC1 34 52 72 22

32 12 DC2 35 53 73 23

33 13 DC3 36 54 74 24

34 14 DC4 37 55 75 25

35 15 NAK 40 56 76 26

36 16 SYN 41 57 77 27

37 17 ETB 42 58 78 30

38 18 CAN 43 59 79 31

39 19 EM 44 5A 7A 32

3A 1A SUB 00 5B 1C FS 61

Display code 00 is undeﬁned at sites using the 5C 7C 75

63-character set. 5D 01 SOH 62

3A 1A SUB 63 5E *. 7E ** At. 76

3B 1B ESC 77 5F 7F DEL 65

3C 7B 72

3D 1D GS 54

3E 1E RS 73

3F 1F US 71

tyhen these characters are copied from or to a tape, the characters remain the same and the code changes

from/to ASCII to/from display code.

™These characters do not exist in display code. When the characters are copied from a tape, each ASCII

character is changed to an alternate display code character. The corresponding codes are also changed.

Example: When the system copies a lowercase a, 61^, from tape, it writes an uppercase A, 01g.

™*A display code space always translates to an ASCII space.

r60471400 G A-7

TABLE A-4. EBCDIC 9-TRACK CODED TAPE CONVERSION

EBCDIC

Code

Conversiont

Code

(Hex) Char

7 A | :

Display code

63-character

space

(

)

Character and

Code Conversion™

Code

(Hex)

00 is undeﬁ

set.

Char

Display

Codettt

ASCII

Char

NUL

IFS

ACK

SOH

EOT

ESC

ENQ

DEL

IRS

IUS

SUB

ned at

SUB

ETX

BEL

IGS

STX

space

(

)

space

Code

(Octal)

sites using

the

EBCDIC

Code

Conversiont

Code

(Hex)

Char

Character and

Code Conversion™

Code

(Hex)

Char

DLE

DC1

DC2

DC4

NAK

SYN

ETB

CAN

Display

Codettt

ASCII

Char

Code

(Octal)

ALL EBCDIC codes not listed translate to display code 55g (space). A display code space always

translates to an EBCDIC space.

™These characters do not exist in display code. When the characters are copied from a tape, each EBCDIC

character is changed to an alternate display code character. The corresponding codes are also changed.

Example: When the system copies a lowercase a, &li0, from tape, it writes an uppercase A, OI3.

ttt

'When these characters are copied from or to a tape, the characters remain the same (except EBCDIC codes

^16/ 4r"l6/ 5A«|6, and 5F-|0) and the code changes from/to EBCDIC to/from display code.

• A - 8 60471400 G

TABLE A-5. 7-TRACK CODED TAPE CONVERSIONS

External ASCII Octal Display External ASCII Octal Display

BCD Character Code BCD Character Code

01 34 40 46

02 35 41 12

03 36 42 13

04 37 43 14

05 40 44 15

06 41 45 16

07 42 46 17

10 43 47 20

11 44 50 21

12* 33 51 22

13 54 52 66

14 ■i64 53 53

15 74 54 47

16t 63 55 70

17 61 56 71

20 space 55 57 73

21 50 60 45

22 23 61 01

23 24 62 02

24 25 63 03

25 26 64 04

26 27 65 05

27 30 66 06

30 31 67 07

31 32 70 10

32 62 71 11

33 56 72 72

34 51 73 57

35 65 74 52

36 60 75 75

37 67 76 .A. 76

77 77

TAs explained in the text of this appendix, convers ion of these codes depends on whether the tape is

being read or written.

60471400 G A-9 •

°^

5°

*°

•^3

*§

E-

^--S£

IM CM

tf<

2«

1 T'0

1 oS)"-

IO Ul

T . U .

• U .

o25

m f ﬂ

CM CM

4°

xfta

too

cyu.

CM CM

ing

I0O

£!>

o*" "§

•■o

CM CM

IM CM

po8 So

i r»

-8

CT*

70>

o"" •-S CM

1".

?CM

1 r *

CM CM

1 r»

CTCT

1 !«•

1 r»

o"" 2§

C M ^

CM CM CM

to!?

op™

CM CM

i m

r » r « .

1 m

^o°~ 0)

-O

-o

CO1

0) 0)0. ence 7«

cn3 CM1"

tO ca

CT 43

0)0 Set 7s

- c c

„o«° OS

ooo

!-. CA

OOT

-8

o>u.

CM°

imS

— OT

CT*"

o> —

tZX

— 0

o*~ r»

1 0)

a2a CM

or— er

785

co<

t7?

3 f 3

in<

> T >

i T i >— >

c.2

7CM

— *

— C M _ _ i - /

_jo>_i

SSo

o"* co - 5- 45

o — a

CMOS

.0—JS

coco

S I T o

xtSO

•Qt-O

in co

i»

r»0B

0»— O)

cj"

£ — £

1 0 1

JtTjt

CTCT

1 0 1

eSe

1 cn

e— c

O — 0

o"" l "

c u t a .

OOO

O-O (C-CC

wow

CT1" ,£ in

>ei>

Ul Ul

xox

>2>

NON

op«

CMO

J,tU ap in

fu.

m i n 2§

o*" 1*

©CO® < — <

CM CM

1 C J

0,2a,

coco

qSd 78

uiSu. 78

u.Su. o2o 78

i2i 78

CM 75 CM CM

' o

xt-xc

CTCT

1 a

-1 — -1 ts

s-s

1 O

ZtZ 7g

0-0

o°~ CT u.

o ° o

u. CM

C M C M

p»

C T C O

u. IA

i n u i

( 0 ( 0

u. 00

0 0 C O

0 ) 0 ) ■ ■CO •■

SO Ul

7v 2 v

11 a 11

III

t o g

A 2 A

r ^ t n

IM 15

: 0 0 :

CT<n

tn — t/i #o# «S<a

» to

i n v

i n i n

iJ" Ul

+ — +

2. 1 - 1

o°°'

— O

1 —

UJ —UJ

a** -q>-

tlr-tl

O - O

sis

O-O

s!5

O-t-

3?3

OenO <7<

z«z W01M

CO m CO

UIOUJ

Z9z

< T <

°?

5J.5

U J — U J

l»

co oo as

OTC0OT

U(j|U

WTW

UIOUI

si? «»7w

O t x 2

OT7w

cc-£

r«

S?2

oo"°

A-

= C M = 8~8

tests

HCNt-

ui-ui

o7o

UJ01UI

a a t a

z?z

UJOUI

v T w

<o<

Sl7u

ooooo

O T — W

ffi— oa

»"CM^

«°

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7°

KcmOC

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2§

7°

828

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W — O T

tfSXX

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/*S*?!\

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.^-*^s

A-10 60471400 G

0 ^ S gg

£^

curt

cap

En tti

o«

«s

WOW

._— ._ Jt — 4t

to it -

{2 IO

3 i n

OT C W

UJ —ui

O - O

is8

8S8

-2. =2=

s-s

ZCMZ

> 1 >

M O W

■ik

x4x

teste

**8

x4x

l-CM»-

Ul —U l

eSe

>2> 5 i S

0.05 22

£st

XO)

ul2tu

5s°

Ul*"

NON

2=5

'CO'

..CO =*»=«=

SsS

vsv

3?3

OoiQ

Sifﬁ

co.

z7z

UIO UI

3?«3

o™

I u.

A 2 A

2?8

8S8

t a x :

rs <

-im-)

UITUI

COO CO

Sis

i ?

I Q

-I-

t o b

I I

o o

o =

5 «

60471400 G A - l l •

TABLE A-8. FULL EBCDIC CHARACTER SET

Hexa

decimal

EBCDIC

Code

Octal

12-Bit

EBCDIC

Code

EBCDIC

Graphic

Charactert

EBCDIC

Control

Character

Hexa

decimal

EBCDIC

Code

Octal

12-Bit

EBCDIC

Code

EBCDIC

Graphic

Character1

EBCDIC

Control

Character

00 0000 NUL 41 0101 undeﬁned

01 0001 SOH thru t h r u

02 0002 STX 49 0111

03 0003 ETX 4A 0112

04 0004 PF 4B 0113

05 0005 HT 4C 0114

06 0006 LC 4D 0115

07 0007 DEL 4E 0116

08 0010 undeﬁned 4F 0117

09 0011 undeﬁned 50 0120

0012

0013 SMM

t h r u

0121

thru

undeﬁned

OC 0014 FF 59 0131

OD 0015 CR 5A 0132

OE 0016 SO 5B 0133

OF 0017 SI 5C 0134

10 0020 DLE SD 0135

11 0021 DC1 5E 0136

12 0022 DC2 5F 0137 -i

13 0023 TM 60 0140

14 0024 RES 61 0141

15 0025 NL 62 0142 undeﬁned

16 0026 BS t h r u t h r u

17 0027 IL 69 0151

18 0030 CAN 6A 0152

19 0031 EM 6B 0153

1A 0032 CC 6C 0154

1B 0033 CU1 6D 0155

1C 0034 IFS 6E 0156 >"

1D 0035 IGS 6F 0157

1E 0036 IRS 70 0160 undeﬁned

1F 0037 IUS thru t h r u

20 0040 DS 78 0170

21 0041 SOS 79 0171

22 0042 FS 7A 0172

23 0043 undeﬁned 7B 0173

24 0044 BYP 7C 0174

25 0045 LF 7D 0175

26 0046 ETB or EOB 7E 0176

27 0047 ESC or PRE 7F 0177 •i

28 0050 undeﬁned 80 0200 undeﬁned

29 0051 undeﬁned 81 0201

2A 0052 SM 82 0202

2B 0053 CU2 83 0203

2C 0054 undeﬁned 84 0204

2D 0055 ENQ 85 0205

2E 0056 ACK 86 0206

2F 0057 BEL 87 0207

30 0060 undeﬁned 88 0210

31 0061 undeﬁned 89 0211

32 0062 SYN 8A 0212 undeﬁned

33 0063 undeﬁned t h r u thru

34 0064 PN 90 0220

35 0065 RS 91 0221

36 0066 UC 92 0222

37 0067 EOT 93 0223

38 0070 undeﬁned 94 0224

39 0071 undeﬁned 95 0225

3A 0072 undeﬁned 96 0226

3B 0073 CU3 97 0227

3C 0074 DC4 98 0230

3D 0075 NAK 99 0231

3E 0076 undeﬁned 9A 0232 undeﬁned

3F 0077 SUB t h r u thru

40 0100 space AO 0240

><^^V

• A-12 60471400 G

TABLE A-8. FULL EBCDIC CHARACTER SET (Contd)

/g|ps\

Hexa Octal EBCDIC EBCDIC Hexa Octal EBCDIC EBCDIC

decimal

EBCDIC

Code

12-Bit

EBCDIC

Code

Graphic

Character*

Control

Character

decimal

EBCDIC

Code

12-Bit

EBCDIC

Code

Graphic

Character1

Control

Character

A1 0241 D7 0327

A2 0242 D8 0330

A3 0243 D9 0331

A4 0244 DA 0332 undeﬁned

A5 0245 t h r u t h r u

A6 0246 DF 0337

A7 0247 EO 0340

A8 0250 E1 0341 undeﬁned

A9 0251 E2 0342

AA 0252 undeﬁned E3 0343

thru thru E4 0344

BF 0277 E5 0345

CO 0300 E6 0346

C1 0301 E7 0347

C2 0302 E8 0350

C3 0303 E9 0351

C4 0304 EA 0352 undeﬁned

C5 0305 EB 0353 undeﬁned

C6 0306 EC 0354 rl

C7 0307 ED 0355 undeﬁned

C8 0310 t h r u t h r u

C9 0311 EF 0357

CA 0312 undeﬁned FO 0360

CB 0313 undeﬁned F1 0361

CC 0314 •P F2 0362

CD 0315 undeﬁned F3 0363

CE 0316 F4 0364

CF 0317 undeﬁned F5 0365

DO 0320 F6 0366

D1 0321 F7 0367

D2 0322 F8 0370

D3 0323 F9 0371

D4 0324 FA 0372

D5 0325 FB 0373 undeﬁned

D6 0326 t h r u

t h r u

0377

TGraphic characters sshown are those used on the IBM System/370 standard (PN) print train. Other devices

support subsets or vva ri at ions of th i s character g raphic se t.

60471400 G A-13 •

NETWORK ACCESS METHOD

TERMINAL TRANSMISSION CODE SETS

There are two modes in which coded character data can be

exchanged with a network terminal console. These two

modes, character mode and transparent mode, correspond

to the type of character code editing and translation

performed by the network software during input and output

operations. The transmission mode used by the network

software for input can be selected by the terminal

operator, using a Terminal Interface Program command

(sometimes referred to as a terminal deﬁnition command).

The transmission mode used by the network software for

output can be selected by the application program

providing the terminal facility service.

Character Mode Transmissions

Character mode is the initial and default mode used for

both input and output transmissions. When the network

software services the terminal in character mode, it

translates input characters from the transmission code

used by the terminal into the ASCII code shown in

table A-9. The translation of a speciﬁc transmission code

to a speciﬁc ASCII code depends on the terminal class the

network software associates with the terminal. In

character mode input, the parity of the terminal

transmission code is not preserved in the corresponding

ASCII code; the ASCII code received by the

terminal-servicing facility program always has its eighth

bit set to zero.

Character mode output is translated in a similar manner.

The network software provides the parity bit setting

appropriate for the terminal being serviced, even though

translating from ASCII characters with zero parity bit

settings.

Tables A-10 through A-21 show the character mode

translations performed for each terminal class. The parity

shown in the terminal transmission codes is the parity used

as a default for the terminal class. The parity setting

actually used by a terminal can be identiﬁed to the

network software through a TIP command.

Tables A-10 through A-21 contain the graphic and control

characters associated with the transmission codes used by

the terminal because of the terminal class and code set in

use. The network ASCII graphic and control characters

shown are those of the standard ASCII character set

associated with the ASCII transmission codes of table A-9.

The general case for code translations of character mode

data is summarized in the following paragraphs. This

generalized description permits use of only table A-9 to

explain all speciﬁc cases. The reader can logically extend

this generalized description to allow use of tables A-l

through A-8 as descriptions of character set mapping for

various functions initiated from a terminal. Tables A-l

through A-8 are provided for the reader's use while coding

an application program to run under the operating system.

They do not describe character transmissions between an

application program and the network.

Table A-9 contains the ASCII 128-character set supported

by the Network Access Method. A 96-character subset

consists of the rightmost six columns and includes the

95-character graphic subset referenced previously in this

appendix; the deletion character (DEL) is not a graphic

character. A 64-character subset consists of the middle

four columns. Note that 6-bit display code equivalents

exist for the characters in this 64-character subset only.

Although the network supports the 128-character set, some

terminals restrict output to a smaller subset. This

restriction is supported by replacing the control characters

in columns 0 and 1 of table A-9 with blanks to produce the

96-character subset, and, additionally, replacing the

characters in columns 6 and 7 with the corresponding

characters from columns 4 and 5, respectively, to produce

the 64-character subset.

Similarly, input from a device may be limited to a smaller

subset by the device itself because the device cannot

produce the full 128-character set. A character input from

a device using a character set other than ASCII is

converted to an equivalent ASCII character; characters

without ASCII character equivalents are replaced by the

ASCII blank character.

An application can also cause character replacement (as

described previously for output) as well as character

conversion, by requesting display-coded input from the

network.

The 7-bit hexadecimal code value for each character

consists of the character's column number in the table,

followed by its row number. For example, N is in row E of

column 4, so its value is 4E1g.

Transparent Mode Transmissions

Transparent mode is selected separately for input and

output transmissions. During transparent mode input, the

parity bit is stripped from each terminal transmission code

(unless the N parity option has been selected by a Terminal

Interface Program command), and the transmission code is

placed in an 8-bit byte without translation to 7-bit ASCII

code. Line transmission protocol characters are deleted

from a mode 4C terminal input stream.

When the 8-bit bytes arrive in the host computer, a

terminal servicing facility program such as the Interactive

Facility can right-justify the bytes within a 12-bit byte.

Upon transmission of 12-bit bytes from the host computer,

the leftmost 4 bits (bits 11 through 8) are discarded.

During transparent mode output, processing similar to that

performed for input occurs. The code in each 8-bit byte

received by the network software from the terminal

servicing facility program is not translated. The parity bit

appropriate for the terminal class being used is altered as

indicated by the parity option in effect for the terminal.

The codes are then output in transmission bytes

appropriate for the codes associated with the terminal

class being used. Line transmission protocol characters are

inserted into a mode 4C terminal output stream.

• A-14 60471400 G

TABLE A-9. FULL ASCII CHARACTER SET

■128-Character Set-

•96-Character Subset-

■64-Character Subset ***■

00m*_

B i t s b ^ b j b 2 b , , Column

tttt

oooo

0 0 0 1

0 0 1 0

0 0 1 1

0 1 0 0

0 1 0 1

0 1 1 0

0 1 1 1

0 0 0

0 0 1

0 1 0

0 1 1

1 0 0

1 0 1

1 1 0

1 1 1

NUL

000

SOH

001

STX

002

ETX

003

EOT

004

ENQ

005

ACK

006

BEL

007

010

011

012

013

014

015

016

017

DLE

020

DC1

021

DC2

022

DC3

023

DC4

024

NAK

025

SYN

026

ETB

027

CAN

030

031

SUB

032

ESC

033

034

035

036

037

040

041

042

043

044

045

046

047

(

050

)

051

052

053

054

055

056

057

060

061

062

063

064

065

066

067

070

071

072

073

074

075

076

077

100

101

102

103

104

105

106

107

11 0

111

11 2

113

11 4

115

11 6

117

120

121

122

123

124

125

126

127

130

131

132

133

134

135

136

137

140

141

142

143

144

145

146

147

150

151

152

153

154

155

156

157

160

161

162

163

164

165

166

167

170

171

172

173

174

175

176

DEL

177

LEGEND:

Numbers under characters are the octal values for the 7-bit character codes used within the network.

60471400 G A-15 •

TABLE A-10. CHARACTER CODE TRANSLATIONS, CONSOLE TERMINAL CLASSES 9, 14, 16, AND 17

Terminal EBCDIC Network ASCII Character Mode Use)

Octal

Code Graphict Control Character Octal

Codett Graphic Control Character

000 NUL 000 null

001

002 SOH 001 start of header

STX 002 start of text

003

004 ETX

PF 003

040 space

end of text

005

006 HT

LC Oil

040 space

horizontal tabulate

007 DEL 177 delete

010 undeﬁned 040 space

011 undeﬁned 040 space

012 smm 040 space

013 VT 013 vertical tabulate

014 FF 014 form feed

015 CR 015 carriage return

016 SO 016 shift out

017 SI 017 shift in

020 DLE 020 data link escape

021 DC1 021 device control 1

022 DC2 022 device control 2

023 TM 023 device control 3

024 RES 040 space

025 NL 040 space

026 BS 010 backspace

027 IL 040 space

030 CAN 030 cancel

031 EM 031 end of medium

032 CC 040 space

033 CU1 040 space

034 IFS 034 ﬁle separator

035

036 IGS 035 group separator

IRS 036 record separator

037

040 IUS

DS 037

040 space

unit separator

041 SOS 040 space

042 FS 040 space

043 undeﬁned 040 space

044 BYP 040 space

045 LF 012 linefeed

046 ETB or EOB 027 end of transmission block

047 ESC or PRE 033 escape

050 undeﬁned 040 space

051 undeﬁ ned 040 space

052 SM 040 space

053 CU2 040 space

054 undeﬁned 040 space

055 ENO 005 enquiry

056 ACK 006 positive acknowledgment

057 BEL 007 bell

060 undeﬁned 040 space

061 undeﬁ ned 040 space

062 SYN 026 synchronous idle

063 undeﬁ ned 040 space

064 PN 040 space

065 RS 040 space

066 UC 040 space

067 EOT 004 end of transmission

070 undeﬁned 040 space

071 undeﬁned 040 space

072 undeﬁned 040 space

073 CU3 040 space

074 DC4 024 device control 4

075 NAK 025 negative acknowledgement

076 undeﬁned 040 space

077 SUB 032 substitute

100 space 040 space

A-16 60471400 G

y ^ K v

TABLE A-10. CHARACTER CODE TRANSLATIONS, CONSOLE TERMINAL CLASSES 9, 14,16, AND 17 (Contd)

Terminal EBCDIC Network ASCII (Character Mode Use)

Octal

Code Graphic* Control Character Octal

Codett Graphic Control Character

101 undeﬁned 040 space

thru

111

112 133

113 056

114 074

115 050

116 053

117 041

120 046

121 undeﬁned 040 space

thru

131

132 135

133 044

134 052

135 051

136 073

137 -i 136

140 055

141 057

142 undeﬁned 040 space

thru

151

152 174

153 054

154 045

155 137

156 076

157 077

160 undeﬁned 040 space

thru

170

171 140

172 172

173 043

174 100

175 047

176 075

177 ii 042 ii

200 undeﬁned 040 space

201 141

202 142

203 143

204 144 . d

205 145

206 146

207 147

210 150

211 151

212 undeﬁned 040 space

thru

220

221 152

222 153

223 154

224 155

225 156

226 157

227 160

230 161

231 162

232 undeﬁned 040 space

thru

240

60471400 G A-17 •

TABLE A-10. CHARACTER CODE TRANSLATIONS, CONSOLE TERMINAL CLASSES 9, 14, 16, AND 17 (Contd)

Octal

Code

241

242

243

244

245

246

247

250

251

252

thru

277

300

301

302

303

304

305

306

307

310

311

312

313

314

315

316

317

320

321

322

323

324

325

326

327

330

331

332

thru

337

340

341

342

343

344

345

346

347

350

351

352

353

354

355

thru

357

360

361

362

363

364

365

366

367

Terminal EBCDIC

Graphic1 Control Character

undeﬁned

Network ASCII (Character Mode Use)

Octal

Codett

176

163

164

165

166

167

170

171

172

040

173

101

102

103

104

105

106

107

110

111

040

175

112

113

114

115

116

117

120

121

122

040

134

040

123

124

125

126

127

130

131

132

040

060

061

062

063

064

065

066

067

Graphic

space

Control Character

aZSS

A*%S

A ^ S

A-18 60471400 G

TABLE A-10. CHARACTER CODE TRANSLATIONS, CONSOLE TERMINAL CLASSES 9, 14, 16, AND 17 (Contd)

0<$M^x\

y$f^\

Terminal EBCDIC Network ASCII (Character Mode Use)

Octal

Code Graphic1 Control Character Octal

Codett Graphic Control Character

370

371

372

373

thru

377

undeﬁned

070

071

040

040 space

space

tGraphic characters shown are those used on the IBM System/370 standard (PN) print train. Other devices

support subsets or variations of this character graphic set.

Shown with zero parity (eighth or uppermost bit is always zero).

60471400 G A-19

TABLE A-ll. AMERICAN NATIONAL STANDARD CODE FOR INFORMATION INTERCHANGE (ASCH) WITH 029 PUNCHED

CARD CODES AND EBCDIC TRANSLATION (BATCH OUTPUT DEVICES, TERMINAL CLASSES 9, 14, 16, AND 17)

ASCII

Bit

b4 b3 b2 bx

ASCII

Bit

b4 b3 b2 bx

S7 b6

\ c o l

RowN.

\ C o l

Row\

0 0 0 0 SP

no punch

S P 4 0 F0

8-4

9 7C

11-7

P 07

1 0 0 0 12-8-5

( 4 D 8 F8

12-8

H C8 0-7

X E7

0 0 0 1 12-8-7

! 4 F Fl

12-1

A Cl

11-8

Q D8

1 0 0 1 11-8-5

) 5 D 9 F9

12-9

I C9

0-8

Y E8

0 0 1 0

8-7

7F F2

12-2

B C2

11-9

R D9

1 0 1 0

(A)

11-8-4

* 5 C 8-2

: 7 A

11-1

J Dl

0-9

Z E9

0 0 1 1 8-3

# 7 B F3

12-3

C C3

0-2

S E2

1 0 1 1

(B)

12-8-6

+ 4 E 11-8-6

; 5 E

11-2

K D2 12-8-2

t 4 A

0 1 0 0 11-8-3

$ 5 B F4

12-4

D C4

0-3

T E3 1 1 0 0

(C)

6-8-3

12-8-4

< 4 C 11-3

L D3

0-8-2

\ E0

0 1 0 1 0-8-4

% 6 C F5

12-5

E C5

0-4

U E4

1 1 0 1

(D)

8-6

= 7 E 11-4

M D4

11-8-2

! 5 A

0 1 1 0 12

& 5 0 F6

12-6

F C6

0-5

V E5 1 1 1 0

(E)

12-8-3

0-8-6

> 6 E

11-5

N D5 11-8-7

- i 5 F

0 1 1 1 8-5

7D F7

12-7

G C7

0-6

W E6 1111

(F)

0-1

/ 6 1

0-8-7

? 6 F

11-6

0 D6

0-8-5

LEGEND:

ASCII

EBCDIC

Characte

or EBCDIC Card

DIC Code (Hexad

Code

ecimal)

11-8

1 _

-2

5A — c a r *

'■" * t B L

A-20 60471400 G

■*^5?v

/!$W*P^S

04 <0

SS .,

tt ax

085

§3

1 0*

w£

o§

§|

S Oj

S£

Q»

6§

fH Q

»!

ft ft ft ft ft

o°o m m N^M «■%» »*• -•\. •*• ■ a••• £st. 2 f t 2ft 2 f t 2ft

2 f t

-•

^-I

MOM 343 >2> MON :ft

*ft XSfc

Sft

2 f t

_ • - 08

_<2.j 0-0 a, to. 0-0 Ss. 5ft 5ft 2ft 2 f t 2 f t

K 9 9999t. 2» J8 JR JR

„•• u5 •? K.

5v <i< o2o r,*r\ w2w . 5 . »2o x 2 x 2 f t 2 f t «»2fc 2ft >2fc 2 f t

■5?8 ?* !R !'

^2 f t 2 f t 2 f t 2 f t 2ft 2ft 2ft 2 f t 2ft 2 f t 2 f t 2ft 2ft 2ft 2 f t

78 „s i" 28 "?8 J"

Stl c< «s«» »Ss »£> » = * ■ Sx >z> ••••M =& =ft Sft 2ft Sft 2 f t

..•• iR ,5

1i« 2* j' 2* J* .8

1IB 1* ?8

4i8 i" J"

^-2* .5j E2s c2, «2o a2«. c/2o 2 f t 2 f t 2 f t 2ft 2fc 2 f t

78 «* _. • .9 «• 2s 2s 2» 28 -R

.•• 5ft .5< *2« «2o .So IS •20 .:< 2 f t 2 f t 2 f t 2ft 2 f t 2ft

^f»

2R JR i8 r\

i»

•

2ft 2ft 2 f t 2 f t 2 f t ift 5ft 2 f t 2 f t • •• ■•a ■•*a« »2. .2. .2.

1«»1

ft i: i: i: =ft

=ft ift .-!L i.

.1 i.A 2 A

_•» XX 4* ?R ?■?R 4R ;r <9

o- «s« 2 f t 2 f t =» 2ft 2ft 2ft 2ft 2ft Cft •»-•» . s. —-..-.. r = <

_.° I8 "0 n0 iR -R

4.a

4i8

ft 8ft 2& 2ft 2ft 2ft 2 f t 2 f t 2ft 2ft 2ft •»—— V2v ♦ ^ •

f888888888888 8 8

mm «t

•

2 f t Itt IAAOI cjift ;2ft £2ft ^ f t ti 1 m. aft «8l I, uaft oaft 5?

zaft 2ft Kaft

4Ra•- r»

o°~ 8=fc Sift sift 1* caoft ^ift .3

Lift lil oft 3ft 3ft loft SSft eft uioft < i f t nod

. • • " -4 <* ,4 -? 4. 5ff

5? Ox si* 2 = fc

*2fc 8 = ft 8=fc i=fc £=ft gzft t i r b 5=ft t w ^ f t y=ft d=ft Ssft 5 = fc

8888 8 8 8 83R 28 28 T« 78 t« 7R

.-•• t4 .? *4 -4 -J -*

rf5ft sift S»2ft £2* It 2ft sin 32ft

•

Ssft IMISIL a2ft 42ft 52fc £2ft 52ft y2ft a2ft

COK 10 M)

* ! | <§ • : u5 o9 w| *!

^0r.

8 5 « •• ••

g» « rr

<» ""

1 ] j

i ! !

S = C

S 3 ;

i i

60471400 G A-21 •

TABLE A-13. AMERICAN NATIONAL STANDARD CODE FOR INFORMATION INTERCHANGE (ASCII) WITH 026 PUNCHED

CARD CODES AND EBCDIC TRANSLATION (BATCH OUTPUT DEVICES, TERMINAL CLASSES 9, 14, 16, AND 17)

ASCII

Bit

b4 b3 b2 bj

ASCII

Bit

b4 b3 b2 bl

bb8

\ Col

Row\

\ C o l

Row\

0 0 0 0

no punch

S P 4 0 F0

8-5

« 7D 11-7

P D7

1 0 0 0-8-4

% 6 C 8 F8

12-8

H C8 0-7

X E 7

0 0 0 1 i2-8-7

! 4 F Fl

12-1

A Cl

11-8

Q D8

1 0 0 12-8-4

< 4 C 9 F9

12-9

I C9

0-8

Y E 8

0 0 1 0 8-4

9 7 C F2 12-2

B C2

11-9

R D 9

1 0 1 10

(A)

11-8-4

* 5 C 8-2

: 7 A 11-1

J Dl

0-9

Z E 9

0 0 1 1 0-8-6

> 6 E F3 12-3

C C3

0-2

S E 2

1 0 1

(B)

& 5 0 12-8-7

J 4 F

11-2

K D2

8-7

" 7 F

0 1 0 0 11-8-3

$ 5 B F4

12-4

D C4

0-3

T E 3

1 1 0

(C)

6-8-3 6B

12-0

{ C O

11-3

L D3

12-8-5

( 4 D

0 1 0 1 8-6

7E F5 12-5

E C5

0-4

U E4 1 1 0

(D)

8-3

# 7 B

11-4

M D4

0-8-2

\ E 0

0 1 1 0 0-8-7

? 6 F F6 12-6

F C6

0-5

V E 5

1 1 1 14

(E)

i2-8-3

11-8-7

- i 5 F 11-5

N D5

12-8-6

+ 4 E

0 1 1 1 0-8-5

) 5 D F7 12-7

G C7

0-6

W E6

1 1 1 15

(F)

0-1

/ 6 1

11-8-6

; 5 E

11-6

0 D6

£-8-5

LEGEND:

EBCDI

C Chara(

C Charac

noc «w r BCDIC Card Code

ode (Hexadecima1)

j r . U L U U l L

12-1 n — 1 c o r r t T r r

IL.t3\,Ultr t,

TABLE A-14. CHARACTER CODE TRANSLATIONS, CONSOLE TERMINAL CLASSES 1, 2, AND 5 THROUGH 8

Terminal ASCII (Transparent Mode Use) Network ASCII (Character Mode Use)

Octal

Codet

ASCII

Graphic Control Character^ Octal

Codettt

ASCII

Graphic Control Character

000

003

005

006

011

012

014

017

NUL or ®

ETX or ©

ENQ or WRU or J)

ACK or RU or ©

HT or 0

LF or NL or 1 or 0

FF or FORM or 0

SI or ®

000

003

005

006

Oil

012

014

017

null

end of text

enquiry

positive acknowledgement

horizontal tabulate

linefeed

formfeed

shift in

• A-22 60471400 G

ygS&N. TABLE A-14. CHARACTER CODE TRANSLATIONS, CONSOLE TERMINAL CLASSES 1, 2, AND 5 THROUGH 8 (Contd)

Terminal ASCII (Transparent Mode Use) Network ASCII (Character Mode Use)

Octal

Code

ASCII

Graphic Control Charactertt Octal

Codettt

ASCII

Graphic Control Character

021 DC1 or X-ON or @ 021 device control 1

022 DC2 or TAPE or (ft 022 device control 2

024 DC4 or TAPE or Q 024 device control 4

027 E T B o r © _ 027 end transmission block

030 CAN or CLEAR or ® 030 cancel

033 ESC or ESCAPE or 0 033 escape

035 GS orQ 035 group separator

036 RS or?A) 036 record separator

041 041

042 •i 042 ii

044 044

047 047

050 050

053 053

055 055

056 056

060 060

063 063

065 065

066 066

071 071

072 072

074 074

077 077

101 101

102 102

104 104

107 107

110 110

113 113

115 115

116 116

120 120

123 123

125 125

126 126

131 131

132 132

134 134

137 _or— 137

140 140

143 143

145 145

146 146

151 151

152 152

154 154

157 157

161 161

162 162

164 164

167 167

170 170

173 173

174 | ort or | 174

175

Lor-i

175

176 176

201 SOH or ® 001 start of header

202 STX or © 002 start of text

204 EOT or (P) 004 end of transmission

207 BELL or <g) 007 bell

210 BS or—or (JH) 010 backspace

213 VTo r ® 013 vertical tabulate

215 CR or RETURN or (0) 015 carriage return

60471400 G A-23 •

TABLE A-14. CHARACTER CODE TRANSLATIONS, CONSOLE TERMINAL CLASSES 1, 2, AND 5 THROUGH 8 (Contd)

Terminal ASCII (Transparent Mode Use)

Octal ASCII

Code Graphic

216

220

223

225

226

231

232

234

237

240 SPACE

blank

243 //

245

246

251

252

254

257

261

262

264

267

270

273

275

276

300

303

305

306

311

312

314

317

321

322

324

327

330

333

335

336 Aor—'

341

342

344

347

350

353

355

356

360

363

365

366

371

372

377

Control Charactertt

SO or (Q)

DLE or ®

DC3 or X-OFF or 0

NAK or-or (Q) _

SYN or LINE CLEAR or 0

EM or RESET or 0

SUB or tor®

FSor0

USor0

DEL or RUBOUT

Network ASCII (Character Mode Use)

Octal

Codettt

016

020

023

025

026

031

032

034

037

040

043

045

046

051

052

054

057

061

062

064

067

070

073

075

076

100

103

105

106

111

112

114

117

121

122

124

127

130

133

135

136

141

142

144

147

150

153

155

156

160

163

165

166

171

172

177

ASCII

Graphic

space

[

]

Control Character

shift out

data link escape

device control 3

negative acknowledgement

synchronous idle

end of medium

substitute

ﬁle separator

unit separator

delete

Shown with even parity, which is the default for these terminal classes (unless PA=N, an application

program receives the same code as in character mode).

"A circle around a character indicates that the character key is pressed in conjunction with a CTL, CTRL,

CNTRL, or CONTROL key to generate the code.

tttshown with zero parity (eighth or uppermost bit is always zero).

A^S\

A-24 60471400 G

TABLE A-15. CHARACTER CODE TRANSLATIONS, ASCII TERMINAL CLASSES 10 AND 15

Terminal ASCIlt

Octal

Codett

040

043

045

046

051

052

054

057

061

062

064

067

070

073

075

076

100

103

105

106

111

112

114

117

121

122

124

127

130

133

135

136

241

242

244

247

250

253

255

256

260

263

265

266

271

272

274

277

301

302

304

307

310

313

315

316

320

323

325

Keyboard or Printer Graphic

ASCII

blank

)

CDC

Blank

( (

+ +

0 0

5 5

6 6

< <

A A

B B

D D

6 G

H H

K K

M M

N N

P P

S S

U U

029

Card Code

no punch

8-3

0-8-4

11-8-5

11-8-4

0-8-3

0-1

11-8-6

8-6

0-8-6

8-4

12-3

12-5

12-6

12-9

11-1

11-3

11 - *

11-8

11-9

0-3

0-6

0-7

12-0 or

12-8-2

11-0 or

11-8-2

11-8-7

12-8-7

8-7

11-8-3

8-5

12-8-5

12-8-6

12-8-3

8-2

12-8-4

0-8-7

12-1

12-2

12-4

12-7

12-8

11-2

11-4

11-5

11-7

0-2

0-4

026

Card Code

no punch

0-8-6

8-6

0-8-7

12-8-4

11-8-4

0-8-3

0-1

12-8-7

8-3

11-8-7

11-8-5

12-3

12-5

12-6

12-9

11-1

11-3

11-6

11-8

11-9

0-3

0-6

0-7

12-0 or

12-8-3

11-0 or

11-8-2

12-8-6

0-8-2

8-4

11-8-3

8-7

0-8-4

12-8-3

8-2

8-5

11-8-6

12-1

12-2

12-4

12-7

12-8

11-2

11-4

11-5

11-7

0-2

0-4

Network ASCII (Character Mode Use)

Octal Codem

Input or Output Console Output Only

040

043

045

046

051

052

054

057

061

062

064

067

070

073

075

076

100

103

105

106

111

112

114

117

121

122

124

127

130

133

135

136

041

042

044

047

050

053

055

056

060

063

065

066

071

072

074

077

101

102

104

107

110

113

115

116

120

123

125

140

143

145

146

151

152

154

157

161

162

164

167

170

173

175

176

Graphic

141

142

144

147

150

153

155

156

160

163

165

space

)

60471400 G A-25 •

TABLE A-15. CHARACTER CODE TRANSLATIONS, ASCH TERMINAL CLASSES 10 AND 15 (Contd)

Terminal ASCIlt Network ASCII (Character Mode Use)

Octal

Codett

Keyboard or Printer Graphic 029

Card Code

026

Card Code

Octal Codettt

Graphic

ASCII CDC Input or Output Console Output Only

326

331

332

334

337 r*

0-5

0-8

0-9

0-8-2

0-8-5

0-5

0-8

0-9

12-8-5

0-8-5

126

131

132

134

135

166

171

172

174

177

'Escape codes and control codes are not listed. These are not treated as network data and have no

equivalent character mode translations.

tt Shown with odd parity, the only possible parity selection for these terminal classes.

tttshown with zero parity (eighth or uppermost bit is always zero). During output, codes 000 through

0373 are converted to code 040g (blank). Codes for lowercase ASCII characters sent to the console

are converted to the codes for the equivalent uppercase characters supported by the terminal, as

shown; codes for these lowercase characters cannot be sent to batch devices without causing errors.

A^i^S.

TABLE A-16. CHARACTER CODE TRANSLATIONS, BCD TERMINAL CLASSES 10 AND 15

Terminal External BCDt Network ASCII (Character Mode Use)

Octal

Codett

Keyboard or Printer Graphic 029

Card Code

026

Card Code

Octal Codem

Graphic

ASCII CDC Input or Output Console Output Only

020 8-2 8-2 072

040 11 11 055

043 11-3 11-3 114 154

045 11-5 11-5 116 156

046 11-6 11-6 117 157

051 11-9 11-9 122 162

052 12-8-7 11-0 041

054 11-8-4 11-8-4 052

057 0-8-6 11-8-7 076

061 12-1 12-1 101 141

062 12-2 12-2 102 142

064 12-4 12-4 104 144

067 12-7 12-7 107 147

070 12-8 12-8 108 148

073 12-8-3 12-8-3 056

075 12-0 12-8-5 134 174

103 063

105 065

106 066

111 071

112 060

114 11 8-5 or

8-7 8-4 042 ii

117 r. 8-4 8-7 133 173

121 0-1 0-1 057

122 0-2 0-2 123 163

124 0-4 0-4 125 165

127 0-7 0-7 130 170

130 0-8 0-8 131 171

133 0-8-3 0-8-3 054

135 r* 0-8-5 0-8-5 137 177

• A-26 60471400 G

TABLE A-16. CHARACTER CODE TRANSLATIONS, BCD TERMINAL CLASSES 10 AND 15 (Contd)

Octal

Codett

136

241

242

244

247

250

253

255

256

263

265

266

271

272

274

277

301

302

304

307

310

313

315

316

320

323

325

326

331

332

334

337

320

Terminal External BCDt

Keyboard or Printer Graphic

ASCII

blank

(

A or

blank

CDC

)

blank

(

-i or ■

or none

029

Card Code

8-3

11-1

11-2

11-4

11-7

11-8

11-8-3

12-8-7

12-3

12-5

12-6

12-9

12-8-4

11-8-5

11-8-6

8-6

11-8-7

0-8-4

no punch

0-3

0-5

0-6

0-9

0-8-2

12-8-5

0-8-7

none

026

Card Code

0-8-6

11-1

11-2

11-4

11-7

11-8

11-8-3

11-8-5

11-8-6

12-3

12-5

12-6

12-9

12-0

12-8-4

12-8-7

8-3

8-5

8-6

no punch

0-3

0-5

0-6

0-9

0-8-2

0-8-4

0-8-7

none

Network ASCII (Character Mode Use)

Octal Codem

Input or Output Console Output Only

043

112

113

115

120

121

044

047

077

103

105

106

111

074

051

073

061

062

064

067

070

075

100

045

040

124

126

127

132

135

050

046

152

153

155

160

161

143

145

146

151

140

164

166

167

172

175

136,

176

Graphic

•

)

space

(

tEscape codes and control codes are not listed. These are not treated as network data and have no

equivalent character mode translations.

ttshown with odd parity, the only possible parity selection for these terminal classes.

mshown with zero parity (eighth or uppermost bit is always zero). During output, codes 000 through 0378

are converted to code 320g (blank). Codes for lowercase ASCII characters sent to the console are

converted to the codes for the equivalent uppercase characters supported by the terminal, as shown;

codes for these lowercase characters cannot be sent to batch devices without causing errors.

* Input and output of this symbol is not possible on some terminals. BCD transmission conventions

support the rubout symbol ■ as an internal terminal memory parity error indicator instead. The ASCII

codes 136g and 176g are output as a blank.

60471400 G A-27 •

TABLE A-17. CHARACTER CODE TRANSLATIONS, CONSOLE TERMINAL CLASSES 11, 12, AND 13

Terminal ASCII (Transparent Mode Use)

Octal

Codet

001

002

004

007

010

013

015

016

020

025

026

031

032

034

037

040

043

045

046

051

052

054

057

061

062

064

067

070

073

075

076

100

103

105

106

111

112

114

117

121

122

124

127

130

133

135

136

141

142

144

147

150

153

155

156

160

163

165

166

171

172

177

ASCII

Graphic

SPACE

blank

[

]

a or

Control Charactertt

SOH or

STX or

EOT or

BELL or

BS or-or®

VT or ®

CR or RETURN or ®

SO or (N)

DLE or (P)

NAK or—or ®

SYN or LINE CLEAR or ®

EM or RESET or ®

SUB or t or ®

FS or ®

US or ^

DEL or RUBOUT

Octal

Codettt

Network ASCII (Character Mode Use)

001

002

004

007

010

013

015

016

020

025

026

031

032

034

037

040

043

045

046

051

052

054

057

061

062

064

067

070

073

075

076

100

103

105

106

111

112

114

117

121

122

124

127

130

133

135

136

141

142

144

147

150

153

155

156

160

163

165

166

171

172

177

ASCII

Graphic Control Character

space

start of header

start of text

end of transmission

bell

backspace

vertical tabulate

carriage return

shift out

data link escape

negative acknowledgement

synchronous idle

end of medium

substitute

ﬁle separator

unit separator

delete

• A-28 60471400 G

A^E&S.

TABLE A-17. CHARACTER CODE TRANSLATIONS, CONSOLE TERMINAL CLASSES 11,12, AND 13 (Contd)

Terminal ASCII (Transparent Mode Use) Network ASCII ( Character Mode Use)

Octal

Codet

ASCII

Graphic Control Charactertt Octal

Codettt

ASCII

Graphic Control Character

200 NUL or ® 000 null

206 ACK or RU or (J) 006 positive acknowledgement

211 H T o r ® ^ Oil horizontal tabulate

212 LF or NL or 1 or Q)

or NEW LINE 012 linefeed

SI or ® 014 formfeed

217 017 shift in

221 DC1 or X-ON or ® 021 device control 1

222 DC2 or TAPE or (F?L 022 device control 2

223 DC3 or X-OFF or l|) 023 device control 3

224 DC4 or TAPE or ®f 024 device control 4

227 ETB or ® 027 end transmission block

230 CAN or CLEAR or (x) 030 cancel

233 ESC or ESCAPE orTf) 033 escape

235 GS or® 035 group separator

236 RS or® 036 record separator

241 041

242 042 ii

244 044

247 047

250 050

253 053

255 055

256 056

260 060

263 063

265 065

266 066

271 071

272 072

274 074

277 077

301 101

302 102

304 104

307 107

310 110

313 113

315 115

316 116

320 120

323 123

325 125

326 126

331 131

332 132

334 134

337 _ or *~ 137

340 140

343 143

345 145

346 146

351 151

352 152

354 154

357 157

361 161

362 162

364 164

367 167

370 170

60471400 G A-29 •

TABLE A-17. CHARACTER CODE TRANSLATIONS, CONSOLE TERMINAL CLASSES 11, 12, AND 13 (Contd)

Terminal ASCII (Transparent Mode Use)

Octal

Codet

373

374

375

376

ASCII

Graphic

I or t or

~or -i

Control Charactertt

Network ASCII (Character Mode Use)

Octal

Codettt

173

174

175

176

ASCII

Graphic Control Character

Shown with odd parity, which is the default for these terminal classes (unless PA=N, an application

program receives the same code as in character mode).

"5.,™ cle a!£u™„a character indicates that the character key is pressed in conjunction with a CTL, CTRL,

CNTRL, or CONTROL key to generate the code.

mShown with zero parity (eighth or uppermost bit is always zero).

TABLE A-18. ASCII CHARACTER CODE TRANSLATIONS,

_, 1

EBCD CONSOLE TERMINAL CLASS 4

Terminal EBCD (Transparent Mode Use) Network ASCII (Character Mode Use)

Octal

Codet EBCD

Graphictt Control Character Octal

Codettt ASCII

Graphic Control Character

000 space 040 space

001 or - 137 or 055 or -

002 t or @ 140 or 100 * or @

003 + or & 053 or 046 + or &

004 * or 8 052 or 070 * or 8

005 Q or q 121 or 161 Q or q

006 Y or y 131 or 171 Y or y

007 H or h 110 or 150 H or h

010 : or 4 072 or 064 : or 4

011 M or m 115 or 155 M or m

012 U or u 125 or 165 U or u

013 D or d 104 or 144 D or d

014 PN or PUNCH ON 021 device control 1 (tape on)

015 RES or RESTORE 000 null

016 BY or BYPASS 000 null

017 PF or PUNCH OFF 023 device control 3 (tape off)

020 < or 2 074 or 062 < or 2

021 K or k 113 or 153 K or k

022 S or s 123 or 163 S or s

023 B or b 102 or 142 B or b

024 ) or 0 051 or 060 ) or 0

025 undeﬁned 000 null

026 undeﬁned 000 null

027 undeﬁned 000 null

030 • or 6 041 or 066 ' or 6

031 0 or o 117 or 157 0 or o

032 W or w 127 or 167 W or w

033 F or f 106 or 146 F or f

034 UCS or UPPERCASE 017 shift in§

035 BS or BACKSPACE 010 backspace

036 EOB 027 end transmission block§

shift out§

037 LCS or LOWERCASE 016

040 = or 1 075 or 061 = or 1

041 J or j 112 or 152 J or j

042 ? or / 077 or 057 ? or /

043 A or a 101 or 141 A or a

044 ( or 9 050 or 071 ( or 9

045 R or r 122 or 162 R or r

046 Z or z 132 or 172 Z or z

047 I or i 111 or 151 I or i

• A-30 60471400 G

TABLE A-18. ASCII CHARACTER CODE TRANSLATIONS, EBCD CONSOLE TERMINAL CLASS 4 (Contd)

Terminal EBCD (Transparent Mode Use) Network ASCII (Character Mode Use)

Octal

Codet

EBCD

Graphictt Control Character Octal

Codettt

ASCII

Graphic Control Character

050 % or 5 045 or 065 % or 5

051 N or n 116 or 156 N or n

052 V or v 126 or 166 V or v

053 E or e 105 or 145 E or e

054 R0 or READER STOP 000 null

055 NL or CR or RETURN 015 carriage return

056 LF or LINE FEED 012 line feed

057 HT or TAB 006 horizontal tabulate

060 ; or 3 073 or 063 ; or 3

061 L or 1 114 or 154 L or 1

062 T or t 124 or 164 T or t

063 C or c 103 or 143 C or c

064 " or # 042 or 043 " or #

065 ! or $ 041 or 044 ! or $

066 1 or , 174 or 054 i o r ,

067 ~i or . 136 or 056 «*• or .

070 > or 7 076 or 067 > or 7

071 P or p 120 or 160 P or p

072 X or x 130 or 170 X or x

073 G or g 107 or 147 G or g

end of transmission'

074 EOT 004

075 IL or IDLE or NULL 000 n u l l .

start of header5

076 PRE or PREFIX 001

077 DEL 177 delete

100 space 040 space

101 _ or - 137 or 055 or -

102 4 or ? 140 or 100 * or @

103 + or & 053 or 046 + or &

104 * or 8 052 or 070 * or 8

105 Q or q 121 or 161 Q or q

106 Y or y 131 or 171 Y or y

107 H or h 110 or 150 H or h

110 : or 4 072 or 064 : or 4

111 M or m 115 or 155 M or m

112 U or u 125 or 165 U or u

113 D or d 104 or 144 D or d

114 PN or PUNCH ON 021 device control 1 (tape on)

115 RES or RESTORE 000 null

116 BY or BYPASS 000 null

117 PF or PUNCH OFF 023 device control 3 (tape off)

120 < or 2 074 or 062 < or 2

121 K or k 113 or 153 K or k

122 S or s 123 or 163 S or s

123 B or b 102 or 142 B or b

124 ) or 0 051 or 060 ) or 0

125 undeﬁned 000 null

126 undeﬁned 000 null

127 undeﬁned 000 null

130 1 or 6 041 or 066 ' or 6

131 0 or o 117 or 157 0 or o

132 W or w 127 or 167 W or w

133 F or f 106 or 146 F or f

shift in*

134 UCS or UPPERCASE 017

135 BS or BACKSPACE 010 backspace .

end transmission block5136 EOB 027

137 LCS or LOWERCASE 016 shift out§

140 = or 1 075 or 061 = or 1

141 J or j 112 or 152 J or j

142 ? or / 077 or 057 ? or /

143 A or a 101 or 141 A or a

144 ( or 9 050 or 071 ( or 9

145 R or r 122 or 162 R or r

146 Z or z 132 or 172 Z or z

147 I or i 111 or 151 I or i

60471400 A-31

TABLE A-18. ASCII CHARACTER CODE TRANSLATIONS, EBCD CONSOLE TERMINAL CLASS 4 (Contd)

Terminal EBCD (Transparent Mode Use)

Octal

Codet

150

151

152

153

154

155

156

157

160

161

162

163

164

165

166

167

170

171

172

173

174

175

176

177

000

175

EBCD

Graphic1"1"

% or 5

N or n

V or v

E or e

or 3

or 1

or t

or c

or #

or $

or ,

—i or .

> or 7

P or p

X or x

G or g

space*

spacej

space*

space5

Control Character

R0 or READER STOP

NL or CR or RETURN

LF or LINE FEED

HT or TAB

EOT

IL or IDLE or NULL

PRE or PREFIX

DEL

IL or IDLE or NULLff

IL or IDLE or NULL§§

IL or IDLE or NULLff

IL or IDLE or NULL§§

IL or IDLE or NULLff

IL or IDLE or NULL§§

Network ASCII (Character Mode Use)

Octal

Codettt

045 or 065

116 or 156

126 or 166

105 or 145

000

015

012

006

073 or 063

114 or 154

124 or 164

103 or 143

042 or 043

041 or 044

174 or 054

136 or 056

076 or 067

120 or 160

130 or 170

107 or 147

004

000

001

177

133 thru

135

140

173

175 or 176

002

003

005

007

013 or 014

020

022

024 thru

026

030 thru

037

ASCII

Graphic

% or 5

N or n

V or v

E or e

Control Character

or 3

or 1

or t

or c

or #

or $

! or ,

^ or .

> or 1

P or p

X or x

G or g

[ or \

or ]

null

carriage return

line feed

horizontal tabulate

or *~

end of transmission^

null

start of header9

delete

start of text

end of text

enquire

bell

vertical tabulate

or form feed

data link escape

device control 2

device control 4,

negative acknowledge,

or synchronize

cancel, end of media,

substitute, escape,

ﬁle separator, group

separator, record

separator, or unit

separator

TShown with odd and even parity; odd parity is the default for this terminal class,

the application program receives the same code as in character mode.) (Unless PA=N,

Each input line is assumed to begin in lowercase. Input characters are translated to lowercase ASCII

characters unless preﬁxed by the UCS code. Once a case shift occurs, it remains in effect until

another case shift code is received, the page width is reached, or the line is transmitted to

the host computer. During output, case is preserved by insertion of case shift codes where needed.

mShown with zero parity (eighth or uppermost bit is always zero).

sNot transmitted to the host computer after translation during input.

^Output translation only.

s^ErS.

A-32 60471400 G

TABLE A-19. APL CHARACTER CODE TRANSLATIONS, EBCD CONSOLE TERMINAL CLASS 4

Terminal EBCD-APL (Transparent Mode Use) Network ASCII (Character Mode Use)

Octal

Codet

EBCD-APL

Graphictt Control Character Octal

Codem ASCII-APL

Graphic Control Character

000 space 040 space

001 _ or + 137 or 053 _ or +

002 — or *- 161 or 160 -*■ or —

003 + or X 045 or 146 + or X

004 * or 8 042 or 070 * or 8

005 ? or Q 077 or 121 ? or Q

006 t or Y 171 or 131 t or Y

007 A or H 150 or 110 A or H

010 < or 4 100 or 064 < or 4

011 1 or M 174 or 115 1 or M

012 \ or U 165 or 125 \ or U

013 u or D 144 or 104 l or D

014 undeﬁned 000 null

015 undeﬁned 000 null

016 undeﬁned 000 null

017 undeﬁned 000 null

020 - or 2 055 or 062 - or 2

021 h or K 153 or 113 -i or K

022 i- or S 163 or 123 i- or S

023 1 or B 142 or 102 1 or B

024 a or 0 046 or 060 a or 0

025 undeﬁned 000 null

026 undeﬁned 000 null

027 undeﬁned 000 null

030 > or 6 174 or 066 > or 6

031 o or 0 157 or 117 o or 0

032 w or W - 167 or 127 w or W

033 ~ or F 136 or 106 — or F

034 UCS or UPPERCASE 017 shift in§

035 BS or BACKSPACE 010 backspace

036 E0B 027 end transmission block§

037 LCS or LOWERCASE 016 shift out§

040 " or 1 042 or 061 " or 1

041 o or J 152 or 112 o or J

042 \ or / 134 or 057 \ or /

043 oc or A 141 or 101 oc or A

044 v or 9 041 or 071 v or 9

045 p or R 162 or 122 p or R

046 = or Z 172 or 132 c or Z

047 \ or I 151 or 111 \ or I

050 = or 5 075 or 065 = or 5

051 t or N 156 or 116 t or N

052 U or V 166 or 126 U or V

053 € or E 145 or 105 € or E

054 undeﬁned 000 null

055 NL or CR or RETURN 015 carriage return

056 LF or LINE FEED 012 line feed

057 HT or TAB 006 horizontal tabulate

060 < or 3 074 or 063 < or 3

061 □ or L 154 or 114 □ or L

062 ~ or T 164 or 124 - or T

063 n or C 143 or 103 n or C

064 ) or ] 051 or 135 ) or ]

065 ( or [ 050 or 133 ( or [

066 ; or , 073 or 054 ; or ,

067 : or . 072 or 056 : or .

070 > or 7 076 or 067 > or 7

071 * or P 052 or 120 * or P

072 => or X 170 or 130 = or X

073 V or G 147 or 107 V or G

074 EOT 004 end of transmission^

075 IL or IDLE or NULL 000 null

60471400 G A-33 •

TABLE A-19. APL CHARACTER CODE TRANSLATIONS, EBCD CONSOLE TERMINAL CLASS 4 (Contd)

Terminal EBCD-APL (Transparent Mode Use)

Octal

Codet

076

077

100

101

102

103

104

105

106

107

110

111

112

113

114

115

116

117

120

121

122

123

124

125

126

127

130

131

132

133

134

135

136

137

140

141

142

143

144

145

146

147

150

151

152

153

154

155

156

157

160

161

162

163

164

165

166

167

170

171

172

173

174

EBCD-APL

Graphictt

space

_ or +

-* or —

+ or X

or 8

or Q

or Y

or H

or 4

or M

or U

or D

- or 2

h or K

«- or ,S

l or B

^ or 0

> or 6

o or 0

co or W

— or F

" or 1

0 or J

\ o r

oc or

•v or

p o r

c o r

\ o r I

= or 5

t or N

U or V

€ or E

or 3

or L

or T

or C

or J

or (

; or ,

: or .

> or 7

* or P

= or X

V or G

)

(

Control Character

PRE or PREFIX

DEL

undeﬁned

UCS or UPPERCASE

BS or BACKSPACE

E0B

LCS or LOWERCASE

undeﬁned

NL or CR or RETURN

LF or LINE FEED

HT or TAB

Network ASCII (Character Mode Use)

Octal

Codem

EOT

001

177

040

137 or 053

161 or 160

045 or 146

042 or 070

077 or 121

171 or 131

150 or 110

100 or 064

174 or 115

165 or 125

144 or 104

000

055 or 062

153 or 113

163 or 123

142 or 102

046 or 060

000

174 or 066

157 or 117

167 or 127

136 or 106

017

010

027

016

042 or 061

152 or 112

134 or 057

141 or 101

041 or 071

162 or 122

172 or 132

151 or 111

075 or 065

156 or 116

166 or 126

145 or 105

000

015

012

006

074 or 063

154 or 114

164 or 124

143 or 103

051 or 135

050 or 133

073 or 054

072 or 056

076 or 067

052 or 120

170 or 130

147 or 107

004

ASCII-APL

Graphic

space

_ or +

-* or f

+ or X

* or 8

? or Q

or Y

or H

or 4

or M

or U

or D

- or 2

-i or K

•- or S

i or B

a or 0

> or 6

o or 0

w or W

~ or F

" or 1

° or J

\ o r

cc or

v or

p or

<= or

\ o r I

= or 5

t or N

U or V

e or E

or 3

or L

or T

or C

or 1

or [

or ,

or .

or 7

or P

or X

or G

Control Character

start of header^

delete

null

shift in§

backspace

end transmission block§

shift out§

null

carriage return

line feed

horizontal tabulate

end of transmission^

A-34 60471400 G

TABLE A-19. APL CHARACTER CODE TRANSLATIONS, EBCD CONSOLE TERMINAL CLASS 4 (Contd)

Terminal EBCD-APL (Transparent Mode Use) Network ASCII (Character Mode Use)

Octal

Code1

EBCD-APL

Graphictt Control Character Octal

Codem

ASCII-APL

Graphic Control Character

175 IL or IDLE or NULL 000 null

176 PRE or PREFIX 001 start of header*

177 DEL 177 delete

000 space|§ 047

000 space99 140

000 space9' 173

000 space99 175

175 IL or IDLE or NULLff 002 start of text

175 IL or IDLE or NULL99

IL or IDLE or NULL9|

IL or IDLE or NULL!9

003 end of text

175 005 enquire

175 007 bell

175 IL or IDLE or NULL99

IL or IDLE or NULL§§

013 or 014 vertical tabulate

or form feed

175 020 thru data link escape, device

026 control 1 thru device

control 4,

negative acknowledge,

or synchronize

175 IL or IDLE or NULL§§ 030 thru

037 cancel, end of media,

substitute, escape,

ﬁle separator, group

separator, record

separator, or unit

separator

tShown with odd and even parity; odd parity i s the default for this terminal class. (Unless PA=N,

the application program receives the same cod e as in character mode.)

ttEach input line is assumed to begin in lowerc ase. Input characters are translated to lowercase ASCII

characters unless preﬁxed by the UCS code. Once a case shift occurs, it remains in effect until

another case shift code is received, the page width is reached, or the line is transmitted to

the host computer. During output, case is preserved by insertion of case shift codes where needed.

tttshown with zero parity (eighth or uppermost b it is always zero).

§Not transmitted to the host computer after translation during input.

§§0utput translation only.

yg^s TABLE A-20. ASCII CHARACTER CODE TRANSLATIONS, CORRESPONDENCE

CODE CONSOLE TERMINAL CLASS 4

Terminal Correspondence Code

(Transparent Mode Use) Network ASCII (Character Mode Use)

Octal

Codet Correspondence

Code Graphictt Control Character Octal

Codettt

ASCII

Graphic Control Character

000 space 040 space

001 h or h 137 or 135 [ or ]

002 T or t 124 or 164 T or t

003 J or j 112 or 152 J or j

004 $ or 4 044 or 064 $ or 4

005 0 or o 117 or 157 0 or o

006 L or 1 114 or 154 L or 1

007 ? or / 077 or 057 ? or /

010 % or 5 045 or 065 % or 5

011 " or ' 042 or 041 •• or .

012 E or e 105 or 145 E or e

013 P or p 120 or 160 P or p

60471400 G A-35 •

TABLE A-20. ASCH CHARACTER CODE TRANSLATIONS, CORRESPONDENCE

CODE CONSOLE TERMINAL CLASS 4 (Contd)

Terminal Correspondence Code

(Transparent Mode Use) Network ASCII (Character Mode Use)

Octal

Codet Correspondence

Code Graphic^ Control Character Octal

Codettt

ASCII

Graphic Control Character

014 PN or PUNCH ON 021 device control 1 (tape on)

015 RES or RESTORE 000 null

016 BY or BYPASS 000 null

017 PF or PUNCH OFF 023 device control 3 (tape off)

020 @ or 2 100 or 062 @ or 2

021 056

022 N or n 116 or 156 N or n

023 + or = 053 or 075 + or =

024 Z or z 132 or 172 Z or z

025 undeﬁned 000 null

026 undeﬁned 000 null

027 undeﬁned 000 null

030 i or 6 041 or 066 ! or 6

031 I or i 111 or 151 I or i

032 K or k 113 or 153 K or k

033 Q or q 121 or 161 Q or q

034 UCS or UPPERCASE 017 shift in§

035 BS or BACKSPACE 010 backspace

036 EOB 027 end transmission block§

shift out8

037 LCS or LOWERCASE 016

040 ± or 1 174 or 061 I or 1

041 M or m 115 or 155 M or m

042 X or x 130 or 170 X or x

043 G or g 107 or 147 G or g

044 ) or 0 051 or 060 ) or 0

045 S or s 123 or 163 S or s

046 H or h 110 or 150 H or h

047 Y or y 131 or 171 Y or y

050 & or 7 046 or 067 & or 7

051 R or r 122 or 162 R or r

052 D or d 104 or 144 D or d

053 : or ; 072 or 073 : or ;

054 RO or READER STOP 000 null

055 NL or CR or RETURN 015 carriage return

056 LF or LINE FEED 012 line feed

057 HT or TAB 006 horizontal tabulate

060 # or 3 043 or 063 # or 3

061 V or v 126 or 166 V or v

062 U or u 125 or 165 U or u

063 F or f 106 or 146 F or f

064 ( or 9 050 or 071 ( or 9

065 W or w 127 or 167 W or w

066 B or b 102 or 142 B or b

067 or - 137 or 055 or -

070 * or 8 052 or 070 w or 8

071 A or a 101 or 141 A or a

072 C or c 103 or 143 C or c

073 054

074 EOT 004 end of transmission^

075 IL or IDLE or NULL 000 null

076 PRE or PREFIX 033 escape

077 DEL 177 delete

100 space 040 space

101 h or h 133 or 135 I or ]

102 T or t 124 or 164 T or t

103 J or j 112 or 152 J or j

104 $ or 4 044 or 064 $ or 4

105 0 or o 117 or 157 0 or o

106 L or 1 114 or 154 L or 1

107 ? or / 077 or 057 ? or /

110 % or 5 045 or 065 % or 5

111 " or ' 042 or 041 .. or .

\-36 60471400 G

,/*^s$.

TABLE A-20. ASCII CHARACTER CODE TRANSLATIONS, CORRESPONDENCE

CODE CONSOLE TERMINAL CLASS 4 (Contd)

Terminal Correspondence Code

(Transparent Mode Use) Network ASCII 'Character Mode Use)

Octal

Codet Correspondence

Code Graphictt Control Character Octal

Codem

ASCII

Graphic Control Character

112 E or e 105 or 145 E or e

113 P or p 120 or 160 P or p

114 PN or PUNCH ON 021 device control 1 (tape on)

115 RES or RESTORE 000 null

116 BY or BYPASS 000 null

117 PF or PUNCH OFF 023 device control 3 (tape off)

120 @ or 2 100 or 062 @ or 2

121 056

122 N or n 116 or 156 N or n

123 + or = 053 or 075 + or =

124 Z or z 132 or 172 Z or z

125 undeﬁned 000 null

126 undeﬁned 000 null

127 undeﬁned 000 null

130 t or 6 041 or 066 ! or 6

131 I or i 111 or 151 I or i

132 K or k 113 or 153 K or k

133 Q or q 121 or 161 Q or q

134 UCS or UPPERCASE 017 shift in§

135 BS or BACKSPACE 010 backspace

136 EOB 027 end transmission block§

shift out§

137 LCS or LOWERCASE 016

140 ± or 1 174 or 061 ± or 1

141 M or m 115 or 155 M or m

142 X or x 130 or 170 X or x

143 G or g

) or 0 107 or 147 G or g

144 051 or 060 ) or 0

145 S or s 123 or 163 S or s

146 H or h 110 or 150 H or h

147 Y or y 131 or 171 Y or y

150 & or 7 046 or 067 & or 7

151 R or r 122 or 162 R or r

152 D or d 104 or 144 D or d

153 : or ; 072 or 073 : or ;

154 RO or READER STOP 000 null

155 NL or CR or RETURN 015 carriage return

156 LF or LINE FEED 012 line feed

157 HT or TAB 006 horizontal tabulate

160 # or 3 043 or 063 # or 3

161 V or v 126 or 166 V or v

162 U or u 125 or 165 U or u

163 F or f 106 or 146 F or f

164 ( or 9 050 or 071 ( or 9

165 W or w 127 or 167 W or w

166 B or b 102 or 142 B or b

167 or - 137 or 055 or -

170 * or 8 052 or 070 * or 8

171 A or a 101 or 141 A or a

172 C or c 103 or 143 C or c

173 054

174 EOT 004 end of transmission^

175 IL or IDLE or NULL 000 null

176 PRE or PREFIX 033 escape

177 DEL 177 delete

000 space§§ 047

000 space§§ 134

000 space§§ 136' a.

000 space§§ 140

000 space§§ 173

000 space§§ 175 or 176 } or ~

175 IL or IDLE or NULLff 001 start of header

175 IL or IDLE or NULL§§ 002 start of text

60471400 G A-37 •

TABLE A-20. ASCII CHARACTER CODE TRANSLATIONS, CORRESPONDENCE

CODE CONSOLE TERMINAL CLASS 4 (Contd)

Terminal Correspondence Code

(Transparent Mode Use) Network ASCII (Character Mode Use)

Octal

Codet Correspondence

Code Graphictt Control Character Octal

Codettt ASCII

Graphic Control Character

175

IL or IDLE or NULLff

IL or IDLE or NULL98

IL or IDLE or NULL85

IL or IDLE or NULL88

003

005

007

013 or 014

020

022

024 thru

026

030 thru

037

end of text

enquire

bell

vertical tabulate

or form feed

data link escape

device control 2

device control 4,

negative acknowledge,

or synchronize

cancel, end of media,

substitute, ﬁle separator,

group separator, record

separator, or unit

separator

tShown with odd and even parity; odd parity is the default for this terminal class. (Unless PA=N,

the application program receives the same code as in character mode.)

nEach input line is assumed to begin in lowercase. Input characters are translated to lowercase ASCII

characters unless preﬁxed by the UCS code. Once a case shift occurs, it remains in effect until

another case shift code is received, the page width is reached, or the line is transmitted to

the host computer. During output, case is preserved by insertion of case shift codes where needed.

mShown with zero parity (eighth or uppermost bit is always zero).

8Not transmitted to the host computer after translation during input.

^Output translation only.

TABLE A-21. APL CHARACTER CODE TRANSLATIONS, CORRESPONDENCE

CODE CONSOLE TERMINAL CLASS 4

Terminal Correspondence Code

(Transparent Mode Use) Network ASCII (Character Mode Use)

Octal

Codet

Correspondence

Code APL

Graphictt

Control Character Octal

Codettt ASCII-APL

Graphic Control Character

000

001

002

003

004

005

006

007

010

Oil

012

013

014

015

016

017

020

021

022

space

-* or —

- or T

. or J

< or 4

o or 0

□ or L

\ or /

= or 5

) or ]

€ or E

* or P

~ or 2

: or .

t or N

undeﬁned

040

161 or 160

164 or 124

056 or 112

100 or 064

157 or 117

154 or 114

134 or 057

075 or 065

051 or 035

145 or 105

052 or 120

000

023

136 or 062

072 or 056

156 or 116

space

-♦ or *-

— or T

. or J

< or 4

o or 0

□ or L

\ or /

= or 5

) or ]

e or E

* or P

— or 2

: or .

t or N

null

• A-38 60471400 G

TABLE A-21. APL CHARACTER CODE TRANSLATIONS, CORRESPONDENCE

CODE CONSOLE TERMINAL CLASS 4 (Contd)

Terminal Correspondence Code

(Transparent Mode Use) Network ASCII (Character Mode Use)

Octal

Codet

Correspondence

Code APL

Graph icft

Control Character Octal

Codettt

ASCII-APL

Graphic Control Character

023 + or X 045 or 146 + or X

024 c or Z 172 or 132 <= or Z

025 undeﬁned 000 null

026 undeﬁned 000 null

027 undeﬁned 000 null

030 > or 6 174 or 066 > or 6

031 \ or I 151 or 111 \ o r I

032 h or K 153 or 113 h or K

033 ? or Q 077 or 121 ? or Q

034 UCS or UPPERCASE 017 shift in8

035 BS or BACKSPACE 010 backspace k8

036 E0B 027 end transmission bloc

shift out8

037 LCS or LOWERCASE 016

040 " or 1 042 or 061 " or 1

041 1 or M 174 or 115 I or M

042 => or X 170 or 130 » or X

043 V or G 147 or 107 V or G

044 ^ or 0 045 or 060 a or 0

045 r or S 163 or 123 r or S

046 A or H 150 or 110 A or H

047 t or Y 171 or 131 t or Y

050 > or 7 076 or 067 > or 7

051 p or R 162 or 122 p or R

052 L or D 144 or 104 L or D

053 ( or [ 050 or 133 ( or [

054 undeﬁned 000 null

055 NL or CR or RETURN 015 carriage return

056 LF or LINE FEED 012 line feed

057 HT or TAB 006 horizontal tabulate

060 < or 3 074 or 063 < or 3

061 U or V 166 or 126 U or V

062 \ or U 165 or 125 \ or U

063 _ or F 137 or 106 _ or F

064 v or 9 041 or 071 ■^ or 9

065 co or W 167 or 127 co or W

066 l or B 142 or 102 x or B

067 - or + 055 or 053 - or +

070 ^ o r 8 042 or 070 # or 8

071 oc or A 141 or 101 cc or A

072 n or C 143 or 103 n or C

073 ; or , 073 or 054 ; or ,

074 EOT 004 end of transmission8

075 IL or IDLE or NULL 000 null

076 PRE or PREFIX 033 escape

077 DEL 177 delete

100 space 040 space

101 — or — 161 or 160 -•• or —

102 - or T 164 or 124 - or T

103 . or J 056 or 112 . or J

104 < or 4 100 or 064 < or 4

105 o or 0 157 or 117 o or 0

106 D or L 154 or 114 □ or L

107 \ or / 134 or 057 \ or /

110 = or 5 075 or 065 = or 5

111 ) or ] 051 or 035 ) or ]

112 e or E 145 or 105 e or E

113 * or P 052 or 120 * or P

114 undeﬁned 000 null

115 undeﬁned 000 null

116 undeﬁned 000 null

117 undeﬁned 023 null

120 " o r 2 136 or 062 — or 2

0^S

60471400 G A-39 •

TABLE A-21. APL CHARACTER CODE TRANSLATIONS, CORRESPONDENCE

CODE CONSOLE TERMINAL CLASS 4 (Contd) a^^S

Terminal Correspondence Code

(Transparent Mode Use) Network ASCII (Character Mode Use)

Octal

Codet

Correspondence

Code APL

Graphictt

Control Character Octal

Codettt

ASCII-APL

Graphic Control Character

121 : or . 072 or 056 : or .

122 t or N 156 or 116 t or N

123 + or X 045 or 146 + or X

124 <= or Z 172 or 132 c or Z

125 undeﬁned 000 null

126 undeﬁned 000 null

127 undeﬁned 000 null

130 > or 6 174 or 066 > or 6

131 \ or I 151 or 111 \ o r I

132 h or K 153 or 113 norK

133 ? or Q 077 or 121 ? or Q

134 UCS or UPPERCASE 017 shift in8

135 BS or BACKSPACE 010 backspace

136 E0B 027 end transmission block8

137 LCS or LOWERCASE 016 shift out8

140 " or 1 042 or 061 " or 1

141 1 or M 174 or 115 1 or M

142 => or X 170 or 130 = or X

143 V or G 147 or 107 V or G

144 *• or 0 045 or 060 ^ or 0

145 r or S 163 or 123 r or S

146 A or H 150 or 110 A or H

147 t or Y 171 or 131 t or Y

150 > or 7 076 or 067 > or 7

151 p or R 162 or 122 p or R

152 L or D 144 or 104 L or D

153 ( or [ 050 or 133 ( or [

154 undeﬁned 000 null

155 NL or CR or RETURN 015 carriage return

156 LF or LINE FEED 012 line feed

157 HT or TAB 006 horizontal tabulate

160 < or 3 074 or 063 < or 3

161 U or V 166 or 126 U or V

162 * or U 165 or 125 \ or U

163 _ or F 137 or 106 _ or F

164 v o r 9 041 or 071 v o r 9

165 co or W 167 or 127 co or W

166 1 or B 142 or 102 1 or B

167 - or + 055 or 053 - or +

170 # o r 8 042 or 070 # or 8

171 oc or A 141 or 101 oc or A

172 n or C 143 or 103 n or C

173 ; or , 073 or 054 ; or ,

174 EOT 004 end of transmission8

175 IL or IDLE or NULL 000 null

176 PRE or PREFIX 033 escape

177 DEL 177 delete

000 spaceff 047

000 space||

space||

space88

140

000 173

000 175 or 176 I or r-

175 IL or IDLE or NULL88 001 start of header

175 IL or IDLE or NULL88 002 start of text

175 IL or IDLE or NULL88 003 end of text

175 IL or IDLE or NULL88 005 enquire

175 IL or IDLE or NULL88 007 bell

175 IL or IDLE or NULL88 013 or 014 vertical tabulate

175 IL or IDLE or NULL88 020 or form feed

data link escape

175 IL or IDLE or NULL88 022 device control 2

r^^S

A^^Su

• A-40 60471400 G

TABLE A-21. APL CHARACTER CODE TRANSLATIONS, CORRESPONDENCE

CODE CONSOLE TERMINAL CLASS 4 (Contd)

y/S^

Terminal Correspondence Code

(Transparent Mode Use) Network ASCII (Character Mode Use)

Octal

Codet

Correspondence

Code APL

Graphictt

Control Character Octal

Codettt ASCII-APL

Graphic Control Character

175

IL or IDLE or NULL88

024 thru

026

030 thru

037

device control 4,

negative acknowledge,

or synchronize

cancel, end of media,

substitute, ﬁle

separator, group

separator, record

separator, or unit

separator

tShown with odd and even parity; odd parity is the default for this terminal class. (Unless PA=N,

the application program receives the same code as in character mode.)

ttEach input line is assumed to begin in lowercase. Input characters are translated to lowercase ASCII

characters unless preﬁxed by the UCS code. Once a case shift occurs, it remains in effect until

another case shift code is received, the page width is reached, or the line is transmitted to

the host computer. During output, case is preserved by insertion of case shift codes where needed.

tttshown with zero parity (eighth or uppermost bit is always zero).

8Not transmitted to the host computer after translation during input.

SSOutput translation only.

60471400 G A-41 •

DIAGNOSTICS

Four types of in-line diagnostics are available for CCP.

• Halt messages. These are delivered to the NPU

console when the NPU stops. Normally the NPU

contents are dumped to the host prior to restarting.

These dumps are processed into a dump listing by

the host's Network Dump Analyzer (NDA).

• Alarm messages. These are delivered to the

network operator's (NOP) console. These alarm

messages alert the NOP to check the recent

performance of the NPU and the NPU's controlled

devices (including terminals). This performance is

recorded on the host's engineering ﬁle by CE error

messages and statistics messages.

NOTE

If the user has elected to purchase a

network maintenance contract the

contents of the engineering ﬁle can

be easily analyzed by the Hardware

Performance Analyzer (HPA).

Otherwise the user must devise his

own method for making the host's

engineering ﬁle contents available.

• CE error messages. These messages which reflect

hardware errors are delivered to the host's engi

neering ﬁle. The messages should be processed by

the HPA or the user's analysis program.

• Statistics messages. These messages which reflect

hardware performance (normal or erroneous) are

delivered to the host's engineering ﬁle. The

messages should be processed by the HPA or the

user's analysis program.

ALARM MESSAGES

Alarm messages and the appropriate actions to take in

responding to the messages are described in table B-l.

NOTE

If the user has not elected to purchase a mainte

nance contract for CCP, the NOP should devise a

system for dumping the engineering day ﬁle in

the host, and for analyzing NPU error messages

in that ﬁle.

CE ERROR MESSAGES

CE error messages can be divided into ﬁve categories as

follows:

Modem signal messages (error codes 01 through 03,

OB and OC)

CLA messages (error codes 04 through OA and OD

through 10)

MLIA messages (error code 11)

Coupler messages (error codes 20 through 24 and 26

through 29)

TIP or LIP related messages (2A through 37).

All other codes are unused. These messages are described

in tables B-2 and B-3.

STATISTICS MESSAGE

Refer to table B-4 for statistics message text deﬁnition.

HALT CODE MESSAGES

AND DUMP INTERPRETATION

When the CCP stops the NPU because of an unrecoverable

condition caused by either hardware or software errors, the

CCP delivers a halt message to the NOP console. See

table B-5. This information is also included in the NPU

dump. Format of the halt message is:

HALT xxxxx yyyy

w w w w P O R T I

zzzz BUFFER ADDR I

xxxxx is the address of the program in control I

at the time when the halt condition

occurred or information relating to the

halt code.

yyyy is the halt code (hexadecimal format)

wwww appears only on CLA address out of |

range (0005) and CLA status overﬂow

(000D) codes

zzzz appears only on buffer halt codes |

(000A, 000B, 000C)

TABLE B-l. ALARM MESSAGES

Message Action

From NPU ii/resident

MAINTENANCE ALARM COUPLER

From NPU ii/resident

MAINTENANCE ALARM MLIA

From NPU ii/resident

MAINTENANCE ALARM PORT jj

Find coupler error codes in host day ﬁle

Find MLIA error codes in host day ﬁle

Find CLA, modem messages in host day ﬁle

60471400 G B-l

TABLE B-2. CE ERROR CODES

Code

(Hexadecimal) Signiﬁcance Action

01 Not used None.

02 Abnormal data set ready (DSR) or clear

to send (CTS) None. This is not an error. It occurs as part of

the normal disconnect sequence on some lines.

03 Abnormal data carrier detect (DCD) If this occurs occasionally, ignore it. Otherwise,

call a CE or analyst.

04 Unsolicited output data demand (ODD) Check for CLA duplicate address or CLA address

switch set between two numbers. This error should

not cause concern unless it occurs frequently; if

it occurs frequently, call a CE or analyst.

05 C LA address out of range Same as code 04

06 Illegal mux loop cell format Same as code 03

07 Unsolicited input Same as code 04

08 Input mux loop error Same as code 03

09 Output mux loop error Same as code 03

OA TIP event receiver timeout for ODD Same as code 03

OB TIP event receiver timeout for DCD Same as code 03

OC Abnormal secondary data carrier detect

(SDCD)

This is normal for channels using reverse channel

interrupts. For other channels, call a CE or

analyst.

0D Excessive CLA status messages If this occurs frequently, call a CE or analyst.

0E Not used None.

OF Next character not available (output) Put CLAs in proper priority positions so higher

speed or high-use channels are serviced ﬁrst.

If this does not solve problem, call a CE or

analyst.

10 Data transfer overrun (input) Same as code OF

11 MLIA error status Same as code 03

thru

Not used None. The CE error code part of the CE mes

sage is evidently garbled.

20 Deadman timeout None. This can occur normally due to the host

locking out the 255x due to host processing

higher priority batch tasks.

21 Spurious coupler interrupt This will occur occasionally. If frequent occur

rence, call a CE or analyst.

22 Not used Same as code 12

B-2 60471400 F

-"ﬁlPv

TABLE B-2. CE ERROR CODES (Contd)

Code

(Hexadecimal) Signiﬁcance Action

23 Coupler hardware timeout on input Same as code 03

24 Input data transfer terminated by PPU Same as code 03

25 Not used Same as code 12

26 Not used Same as code 12

27 Output data transfer terminated by

PPU

Same as code 03

28 Hardware timeout on output Same as code 03

29 End of operation (EOP) missing Same as code 03

2A HASP TIP: Too many NAKs received Same as code 03

2B HASP TIP: Bad BCB from HASP TIP Same as code 03

2C HASP TIP: Bad BCB from HASP work

station

Same as code 03

2D HASP TIP: Workstation restart Not an error if workstation is restarting. Other

wise, call CE or analyst.

2E Mode 4 TIP: Card slip error Notify person responsible for maintaining the

terminal. Call CE or analyst.

2F Mode 4 TIP: Auto recognition failed If port shows unusually low volume of trafﬁc,

someone may have called wrong number. Other

wise, call CE or analyst.

30 Mode 4 TIP: No response from terminal Contact terminal operator; have him verify that

terminal is properly conﬁgured with all switches

in correct position. Then call CE or analyst.

31 Mode 4 TIP: Bad response (unexpected

response)

Same as code 30

32 Mode 4 TIP: Error response from

terminal

Same as code 30

33 LIP: Timeout on idle block Same as code 03

34 LIP: Protocol failure (no response to

frame)

Same as code 03

35 LIP: Remote NPU rejected command

from local NPU

Same as code 03

36 LIP: Bad frame detected by CRC An occasional bad frame is normal. If bad frames

occur frequently, call CE or analyst.

37 ASYNC TIP: Parity errors Check for mismatch in parity between terminal

and CCP. If not mismatch, check CLA. Call a

CE or analyst.

60471400 C B-3

TABLE B-3. CE ERROR MESSAGE TEXT DEFINITIONS jtfaE^v

Error Codes

(Hexadecimal) Text Deﬁnition

thru

00 Sl S2

where:

Port number (CLA address)

CLA status byte 1 (logical format)

CLA status byte 2 (logical format)

SI and S2 not used for

ECs 04-07, 0A, 0B, 10

CLA status bvte 1

bits

PLA status bvte 2

CTS DSR DCP RI QM SQD ILE OLF

bits

where:

DTO NCNA

Unused Unused

CTS Clear to send

DSR Data Set readv

DCD Data carrier detect

RI Ring indicator

QM Qualitv monitor

SQD Signal quality detector

ILE Input loop error

OLE OutDut loop error

DTO Data transfer overrun

NCNA Next character not available

ET ILE LD AL

where: ET

ILE

Error type (00 = Error condition restored

01 = Error counts given

02 = MLIA failure)

Input loop error count ) , ,. . . ... _.- _,

Lost data count "ft 1'sled ,fhf = 01

Alarm count ( <2 bV^ each)

LS NS

where: LS

NS Last state

Current state

B-4 60471400 F

TABLE B-3. CE ERROR MESSAGE TEXT DEFINITIONS (Contd)

Error Codes

(Hexadecimal) Text Deﬁnition

thru

EH ST

where: CP and ST Coupler status word

thru

| CP | ST |

where: CP and ST Coupler status word

thru

1 P 1 oo I

w h e r e : P Port number (CLA address)

thru

00 CA TA DT ERR

where:

ERR

Port number (CLA address)

Cluster address

Terminal address

Device type

Error count (not used on message number 37)

thru

00 NID

where:

NID

Port number (CLA address)

Node ID of remote NPU

37 00 CA TA DT TC

where:

Port number (CLA address)

Cluster address

Terminal address

Device type

Terminal class

Coupler Status Word (CP and ST)

1 5 1 4 1 3 1 2 1 1 1 0 9 8 7 6 5 4 3 2 1 0

Alarm —

Chain address zero

Not used

CYBER channel parity error ■

Hardware timeout

NPU status accepted

Order word loaded

Ll Memory parity error

Memory protect fault

L— NPU status register loaded

•— Memory address register loaded

L- External cabinet alarm

•—Transmission complete

^■Transfer terminated by NPU

••Transfer terminated by PPU

60471400 D B-5

TABLE B-4. STATISTICS MESSAGE TEXT DEFINITIONS

Secondary

Function

Code

Text Deﬁnition

NPU STATISTICS

1 2 10 11 Statistics

Words

where:

Word 1

Word 2

Word

Word 8

Word 9

Word 10

Word 11

Service messages generated

Service messages processed

Bad service messages received

Blocks discarded due to bad address

Packets/blocks discarded due to bad format

Times at no regulation

Times at regulation Level 3

Times at regulation Level 2

Times at regulation Level 1

Times at regulation Level 0

Packet protocol timeouts

NOTE: Each word is composed of two bytes,

TRUNK/LINE STATISTICS

p00 HO LRN Word

Word

where:

LRN

Port

Host ordinal

Link remote node - ID of NPU at opposite end of trunk

(always 0 for lines)

Trunk/line statistics words (2 bytes each)

Word 1 Number of blocks transmitted

Word 2 Number of blocks received

Word 3 Number of characters transmitted in good blocks

Word 4 Number of characters received in good blocks

TERMINAL STATISTICS

p00 K0 CA TA DT HO Word

Word

where: P P o r t

HO Host ordinal

C A C l u s t e r a d d r e s s

TA Terminal address

DT Device type (see below)

Terminal statistics words (2 bytes each)

Word 1 Number of good blocks transmitted

Word 2 Number of good blocks received

Word 3 Number of bad blocks

bit

DT = Device Terminal

Class Device type - byte 13

B-6 60471400 C

TABLE B-4. STATISTICS MESSAGE TEXT DEFINITIONS (Contd)

jrGUP*^

Secondary

Function Te x t D e ﬁ n i t i o n

Code

03 TERMINAL STATISTICS (Contd)

Class

Device

0 1 2

Console Card Reader L i ne P r inte r Card Punch Plotter

1M33, etc.

2713

42741

5M40

6H2000

7751-1

8T4014

9HASP HASP HASP HASP HASP

(postprint) (postprint) ( p o s t p r i n t ) (postprint) (postprint)

10 200UT 200UT 200UT

11 714X 714X

12 711-10

13 714 714

14 HASP HASP HASP HASP HASP

( p r e p r i n t ) ( p r e p r i n t ) ( p r e p r i n t ) ( p r e p r i n t ) ( p r e p r i n t )

15 734

16 2780 2780 2780 2780

17 3780 3780 3780 3780

Device = 5 reserved for internal host/NPU use

= 6 reserved for expansion

= 7 reserved for installations

Terminal Class = 18-27 reserved for expansion

= 28-31 reserved for installations

y ^ s

When such a halt occurs, the host normally executes an

upline dump of the NPU main memory, micromemory, and

the ﬁle 1 registers. Thereafter, the host attempts to

reload the NPU main memory. This is accomplished

directly through the coupler for local NPUs; it is

accomplished by use of overlays in the local NPU

connected to the remote NPU in the case of a remote NPU.

For the ﬁrst two loading attempts, a dump is normally

taken. Thereafter, dumps are suppressed.

The NPU can be stopped locally by master clearing it using

the MASTER CLEAR switch on the maintenance control

panel.

60471400 G B-7

TABLE B-5. HALT CODES

Code

(Hexadecimal)

0001

0002

0003

0004

0005

0006

0007

0008

0009

000A

000B

000C

000D

000E

000F

0010

0011

0012

0013

0014

0015

0016

0017

Signiﬁcance

Power failure

Memory parity error

Program protect error

Interrupt count <0

MLIA failure (reported by

MLIA hardware status)

Overran CIB

Branch to zero detected

Invalid halt code

Ran out of buffers

Duplicate release of buffer

Buffer chain error during

buffer get

Buffer out of range

Coupler alarm condition

Monitor stopped

Too many worklists from one

CLA

Force load service message

received

Bad MLIA initialization status

Invalid halt code

Chain address = 0

Invalid halt code

Invalid coupler orderword

Invalid halt code

Action

Reapply power, reload CCP (for momentary failure).

Call CE or analyst.

Check that software breakpoint not accidently left

set. Call CE or analyst.

Same as code 0002

Check installation handbook to ﬁnd if sufﬁcient mem

ory available to handle system conﬁguration. Call CE

or analyst.

Same as code 0002

This is normal if a force load message was entered.

Otherwise, take same action as code 0002.

Same as code 0002

>C3tf??y

/"aaiS\

A ^ S .

A ^ t S

B-8 60471400 D

/*^!K

In some cases, a halt code message is not generated. In

these cases the dump listing, as generated from the host by

the Network Dump Analyzer (NDA) program, must be

consulted to ﬁnd the cause of the failure.

In all eases where the cause of stoppage is not apparent, the

CE or analyst will probably want to consult the dump listing.

The format of the listing is shown later in this section.

HALT CODES

Halt codes can be divided into three categories: 1) those

primarily resulting from incorrect switch settings, 2) those

caused by hardware malfunctions, and 3) those that can be

either hardware or software problems.

The ﬁrst category includes detection of a duplicate CLA

address (halt code 0012). This condition is usually caused by

two CLA switches being set to the same address. Such a

fault can normally be corrected by the operator resetting

the switches.

In the second category, the halt codes are the following:

• power failures (code 0001)

• memory parity error (code 0002)

• memory protect bit error (code 0003)

• bad MLIA initialization status (code 0011)

Such conditions are usually caused by some type of hardware

failure and normally must be repaired by a CE.

The third category of halt codes (all those not already

speciﬁed) are caused either by a hardware failure or by a

software error. To correct this category of problems, the

CE should normally ﬁrst be called to check the hardware. If

the hardware is functioning properly, a system analyst

should be called.

NOTE

Have all upline dumps taken by the host available

for the CE and/or the system analyst.

DUMP INTERPRETATION WITHOUT

HALT MESSAGE

At most times when a halt occurs, halt codes are sent to

the NOP console and dump interpretation is not needed.

However, 1) if a halt occurs after loading but before com

pletion of initialization, or 2) if the system becomes

trapped in a looping condition during initialization (before

the CCP header prints), dump interpretation may be neces

sary to determine which halt has occurred, or in which

subroutine of the initiation section the program is looping.

INTERPRETATION INSTRUCTIONS

When interpreting the upline dump printout to determine

the cause of a halt or looping condition, ﬁrst examine the

contents of memory location 30^6 as reﬂected in the dump

printout. If non-zero, a halt has occurred and the halt code

value is contained in that location.

If memory location 30ig equals zero, examine the address

of the NPINTAB entry in the address table which begins at

fixed memory address 150ie« (This is the table which is

displayed at the end of a successful initialization.

NPINTAB has a ﬁxed address; it is the last non-zero entry

in the address table.) Table B-6 lists the contents of the

address table. Entry NPINTAB gives the starting address

for the NPINTAB table, the format of which is illustrated

in ﬁgure B-l. The NPISFL entry in the NPINTAB table

contains the ﬂags which mark the initialization subroutines

that have completed running when the looping condition

occurred. This information should be given to the system

analyst along with the dump printouts.

A sample dump, formatted by NDA, is shown in ﬁgure B-2.

60471400 F B-9

TABLE B-6. ADDRESS TABLE

Location Address Title/Routine

15016 0 BYWLCB Worklist control block

1JSWLADDR WL entry by LEVELNO

2B1TCB Internal processing TCB

3B1BUFF Internal processing block

4JKMASK Interrupt masks

5 JKTMASK PBAMASK save area — B ase

6CBTIMTBL TIMAL table

7JACT PD controller table

8BECTLBK Buffer control block (BCB)

9BYSTAMP Buffer stamp area

ACLBFSPACE Buffer space in number of small buffers

CNAPORT Port table ~~ Mux

DBQCIB Circular input buffer (CIB)

— s u b

system

FCGLCBS Line control blocks (LCB)

10 CHSUBLCB Sub line control blocks

11 CGTCBS Terminal control blocks (TBC)

Lines

— a n d

12 BJTIPTYPT TIP type table TIPs

13 NJTECT Terminal characteristics table

15 NPINTAB Initialization complete table

17 CCPVER CCP version address

Initializa-

— tion Infor

18 CCPCYC CCP cycle address mation

19 CCPLEV CCP level address

NOTE: Fix

of 8

ed table begins at main me

i successful initialization. mory location 150.ﬁ. Contents of table are displayed at end

a**is

B-10 60471400 C

WORDO (NPSODD)

WORD 1 (NPISFL)

WORD 2 (NPBMLS)

NPSODD

NPISFL

15 14 13 12 11 10

0 0 0 0 0 0

B15 B7 B6 B5 B4 B3 B2 Bl BO

YYYYYYYYYYYYYYYY

NPBMLS

Duplicate CLA address, where XX... XX is the duplicated CLA address between 01 lg and

FE1ﬁ. 00._ indicates preset value (no duplicates), and FFlﬁ indicates no response.

Initialization completion sequence ﬂags, where B15 and B7 through BO indicate start

or completion of various tasks as follows:

B15- All buffers initialized, system initialization completed

B7 - Second phase of buffer initialization started/completed

B6 - Initialization of ﬁxed lines started/completed

B5 - Initialization of MLIA started/completed

B4 - Application initialization started/completed

B3 - Miscellaneous NPU console initialization started/completed

B2 - Initialization of worklist control blocks started/completed

Bl - Initialization of buffers started/completed

BO - Set up program protect bits started/completed

NOTE

A function is completed if the next higher bit is set, otherwise it

was started but not completed.

Bad MLIA initialization status, where any value for YY..YY other than 0009-ﬁ indicates

bad status. Call a Customer Engineer.

Figure B-l. NPINTAB Table Starting Address Format

60471400 D B-ll

NPU DUMP = 0003

CHANNEL

EQUIPMENT

TIME

DATE

NPU NAME

NDA (DN=03)

00.14.05

78/09/02

NODE2

BASE FILE 1 REGISTERS

NDA VER 1.1

header information

Record 1

\DDRESS F ~ ~

oooooo oooo 0508 0500 0000 AEE0 AEE3 3720

000010 0560 0F00 0000 0D00 0004 00E0 BABE

000020 007F 0064 0064 0001 0007 000F 7D55

000030 AAD8 165E ACD8 0000 0000 0001 OOOO Micromemory dump

000040 0001 B720 0000 OOFE 0085 0000 0801 Record 2

000050 0000 0000 0200 8000 0000 0000 0304

000060 OEDA 0000 36B2 B 7 2 3 . . . 0 0 0 0 OOOF 2000 — File 1 registers in groups of 16

000070 1175 0001 0005 0006 401F OOOO 0008 words per line. Code is hexa

000080 0F16 0014 0000 0050 B590 B59F OOOC decimal

000090 12B3 0000 B5B0 OOOO A180 OOOO OOOO

0000A0 86C5 1F27 0018 0000 00F0 OOOO 00F8

0000B0 004D 004D 0000 0000 0071 7D08 OOOO

OOOOCO 0000 0000 0000 0000 0000 OOOO OOOO

OOOODO 001F 0000 BDCO oooo 0000 OOOO OOOO

0000E0 BDF8 0000 2C83 BE85 0000 OOOO OOOO

0000F0 0000 0000 0000 0000 0000 OOOO A A 2 D _

COUPLER STATUS REGISTER 0 0 0 0 " I

NPU STATUS WORD oooo - A

ORDERWORD oooo J

MACROMEMORY

ADDRESS

000000 OBOO OBOO OBOO OBOO OBOO

000010 0011 0807 OOOO OOOO OOOO

000020 0000 OOOO OOOO OOOO OOOO

000030 0000 OOOO OOOO OOOO OOOO

000040 oooo 0044 OOFE OOOO 0002

000050 0001 OOOO 0044 OOOO 0030

000060 0001 472C 1263 111F FFFE

000070 0002 0019 0001 0019 0001

000080 0001 0001 457A 0 0 0 1 . . . OOOO

000090 oooo OOOO OOOO OOOO OOOO

0000F0**0000 OOOO OOOO OOOO OOOO

000100 oooo 1400 1BA8 OOOO 1400

000110 oooo 1400 3715 OOOO 1400

000120 F010 1400 1C4E oooo 1400

000130 oooo 1400 375D oooo 1400

000140 1400 OOOO 1400 D108 1400

000150 1125 11F5 1064 1065 OOOO

000160 1518 1563 15CA 1699 AAD8

000170 OOOO OOOO E8FD E600 OOOO

000180 5400 4761 12AF 1071 CEF6

For a 2552, both base and mux sides

of main memory are dumped. The

base side precedes the mux side.

Identify a record by addresses

5400

0000

0001

0052

0091

0002

0000

OOOO

1C0F

372D

3751

3781

OOOO

6400

A9F6

OOOO

0001

OOOO

0001

OOOO

0040

OOOO

oooo

AF21

oooo

12B3

Main memory dump

Record 3

If lines have identical information,

lines after the ﬁrst are omitted.

New line with unique information

is ﬂagged with **. Sixteen words

per line. Code is hexadecimal.

A^S.

Figure B-2. Sample NPU Dump

B-12 60471400 D

GLOSSARY

jtf'wy&'^s

Accounting Data -

Data collected by the TIP which counts the amount of

I/O batch data passed to or received from a terminal.

Examples: at the end of a card reader input job, the

TIP informs the host of the number of cards read; at

the end of a printer output, the TIP informs the host

of the number of lines of text sent to the printer.

Address -

A location of data (as in the main or micro NPU

memory) or of a device (as a peripheral device or

terminal). The NPU main memory is paged.

APL-

A scientiﬁc programming language characterized by

powerful operators deﬁned as single keyboard symbols.

Application Program -

A program resident in a host computer. The program

provides an information storage, a retrieval, and/or

processing service to a remote user via the data

communications network and the Network Access

Method.

Async Protocol -

The protocol used by asynchronous, teletypewriter-like

devices. For CCP, the protocol is actually the set of

protocols for eight types of real terminals. The

NPU/terminal interface is handled by the ASYNC TIP.

Autoinput -

An output mode that appends the ﬁrst 20 characters

of the output message to the input reply.

Autorecognition -

A capability offered to most terminals which allows

the TIP to generate some device characteristics for

the terminal, rather than having the terminal generate

the information for itself.

Bandwidth -

• For CCP, bandwidth indicates the transfer rate (in

characters per second) between the NPU and the

terminal.

Base System Software -

The relatively invariant set of programs in CCP that

supplies the monitor, timing, interrupt handling, and

multiplexing functions for the NPU. Base software

also includes common areas, diagnostics, and

debugging utilities.

Batch File Command -

A command from RBF in the host which alters the ﬁle

characteristics of subsequent data transfers for a

batch device. The characteristics which can be

changed include: code type, suppressing carriage

control on output, changing ﬁle limits (maximum size

of a ﬁle in characters), and whether or not lace cards

should be generated for a card punch. For HASP and

BSC terminals, transparent mode and 026/029 card

type can be changed from a terminal through a request

to RBF.

Binary Synchronous Communications (BSC) -

A communications protocol supported by the BSC TIP.

This protocol connects IBM 2780 or 3780 terminals to

the NPU using half-duplex synchronous transmissions

in a point-to-point mode. The terminals have batch

devices which use EBCDIC code. Transparent data

exchanges are permitted. The terminals are

structured to have a virtual console (interactive

device). This is composed of a card reader for input

and a printer for output.

BIP-

Block interface package. A group of modules that

provide routing, service message handling, and some

common TIP subroutines including assistance in IVT

block and PRUB formation for upline messages. By

making hold/queue decisions for downline batch

messages, the BIP also has some batch data stream

ﬂow control capability.

Block -

A unit of information used by networks. A block

consists of one or more words (2 bytes/word) and

contains sufﬁcient information to identify the type of

block, its origin, destination, and routing. Differing

block protocols apply to the host/NPU and the

NPU/terminal interfaces.

Block Protocol -

The protocol governing block transfers of information

between the host and the local NPU. Data is

transferred in IVT blocks or PRU blocks (PRUBs).

Break -

An element of a protocol indicating an interruption in

the data stream. User breaks (a break normally

entered by an operator at an interactive terminal)

stops delivery of a message from the host.

Broadcast Message -

A message generated by the system or by an operator

using the system. The message is sent to one

(broadcast one) or all (broadcast all) of the terminals

in the system.

Buffer -

A collection of data in contiguous words. CCP assigns

two sizes of buffers for data and two other sizes of

buffers for internal processing. A buffer usually has a

header of one or more words. Data within a data

buffer is delimited by pointers to the ﬁrst and last

characters (data buffers are character oriented). If

the data cannot all ﬁt into one buffer, an additional

buffer is assigned and is chained to the current

buffer. Buffer assignment continues until the entire

message is contained in the chain of buffers. Buffers

are chained together only to the forward direction.

Buffering -

The process of collecting data together in buffers.

Ordinarily, no action on the data is taken until the

buffer is ﬁlled. Filled buffers include the case where

data is terminated before the end of the buffer and

the remaining space is ﬁlled with extraneous matter.

60471400 G C-l

Buffer Threshold -

The minimum number of buffers available for

assignment to new tasks. As the buffer level falls

toward the threshold, new tasks are rejected

(regulation).

Byte-

A group of contiguous bits. For data handling within

the NPU/host interface, a byte is 8 bits; IVT uses

7-bit ASCII characters with the eighth bit reserved for

parity; PRU uses 6-bit display code right justiﬁed in

the 8-bit space.

Cassette -

The magnetic tape device in an NPU used for

bootstrap loading of off-line diagnostics and (in

remote NPUs) the bootstrap load/dump operation.

CCP-

Communications Control Program. This set of

modules performs the tasks delegated to the NPU in

the network message processing system.

CE Error Message -

A diagnostic message sent upline to the host from the

NPU. The message contains information concerning

hardware and/or software malfunctions.

Character -

A coded byte of data. Host applications processing

interactive data expect ASCII characters; host

applications processing batch data expect display

code. Terminals expect a wide range of codes. The

TIPs are responsible for translating between terminal

codes and host codes.

CIB-

Circular Input Buffer. This ﬁxed buffer is used by the

mux subsystem to collect all data passing upline from

the multiplexer. The buffer is controlled by a put

pointer for the multiplexer and a pick pointer used to

demultiplex data to individual line-oriented data

buffers.

Command Driver -

The hardware driver that controls the mux subsystem.

Common Area -

Areas of main memory dedicated to system and global

data. These are usually below address 100016.

Communications Supervisor (CS) -

A portion of the network software resident in the

host. CS is written as an application program; the

Communications Supervisor coordinates the network-

oriented activities of the host computer and of the

lines and terminals logically linked to it.

Conﬁguration -

See System Conﬁguration.

Connection Number (CN) -

A number specifying the path (line) used to connect

the terminal through the NPU to the host.

Console -

A terminal devoted to network control processing.

Examples of consoles are the Network Operator's

(NOP) terminal and the Local Operator's (LOP)

terminal. A console attached to the NPU can be used

for ofﬂine processing.

Contention -

The state that exists in a bidirectional transmission

line when both ends of the line try to use the line for

transmission at the same time. All protocols contain

logic to resolve the contention situation.

Control Blocks -

(1) The types of blocks used to transmit control (as

opposed to data) information; (2) Blocks assigned for

special conﬁguration/status purposes in the NPU. The

major blocks are line control blocks (LCB), logical link

control blocks (LLCB), logical channel control blocks

(LCCB), terminal control blocks (TCB), queue control

blocks (QCB), buffer maintenance control blocks

(BCB), mux line control blocks (MLCB), text

processing control blocks (TPCB), and diagnostics

control blocks (DCB).

Coupler -

The hardware interface between the local NPU and

the host. Transmissions across the coupler use block

protocol.

CRC-

Cyclic Redundancy Check. A check code transmitted

with blocks/frames of data. It is used by several

protocols including the HASP and CDCCP protocols.

Cross -

The software support system for CCP. These

programs, which are run on the host, support source

code programming in PASCAL, macroassembler, and

microassembler languages. The compiled or assembled

outputs of the Cross programs are in object code

format on host computer ﬁles (source code is also kept

in host ﬁles). The object code ﬁles are processed by

other Cross programs and host installation programs

into a downline load ﬁle for an NPU.

Data-

Information processed by the network or some

components of the network. Data usually has the form

of messages, but commands and status are frequently

transmitted by using the same information packets as

data (for instance, system messages).

Data Compression -

The technique of transmitting a sequence of identical

characters as a control character and a number

representing the length of the sequence. HASP and

BSC protocols support data compression.

Data Set -

A hardware interface which transforms analog data to

digital data and the converse.

DDLTs -

Special diagnostic programs which use a highly

structured table technique to aid the troubleshooter in

isolating a problem.

Debugging -

The process of running a program to rid it of

anomalies. CCP supplies debugging aids for programs

(TUP, PBTIPDG, and PBDEBUG) and for run-time

PASCAL programs (QDEBUG and its associated

programs).

Diagnostics -

Software programs or combinations of programs or

tables which aid the troubleshooter in isolating

problems.

-«%

,'^^S.

C-2 60471400 G

Direct Calls -

The method of passing control directly from one

program to another. This is the usual transfer mode

for CCP. Some CCP calls are indirect, through the

monitor. Such OPS level indirect calls pass

information to the called program through parameter

areas called worklists. See Worklist.

Directories -

Tables in CCP which contain information used to route

blocks to the proper interface and line. There are

directories for source and destination node and for

connection number. A routed message is attached to

the TCB for the line over which the message will pass.

DMA-

Direct Memory Access. The high-speed I/O channel to

the NPU main memory. This channel is used for

host/NPU buffered transfers.

DN-

Destination Node. The network node to which a

message is directed; for instance, the DN of an upline

message may be the host process (CS) which passes the

message to the application program responsible for

processing the message.

Downline -

The direction of output information ﬂow, from host to

I NPU to terminal.

Dump-

The process of transferring the contents of the NPU

main memory, registers, and ﬁle 1 registers to the

host. The dump can be processed by the Network

Dump Analyzer in the host to produce a listing of the

dumped hexadecimal information.

Echo-

The process of displaying a keystroke on a terminal's

display. Echoing can be done from the TIP, from a

modem, or from the terminal itself.

Format Effectors -

Characters in an output data stream that determine

the appearance of data at the terminal. A format

effector usually takes the form of a single character

in the output message. For printers, the character is

translated by the output side of the TIP into a

combination of carriage returns, line feeds, or spaces.

Similarly, FEs for displays can command new lines,

screen clearing, or cursor positioning.

Frame -

A medium for transmitting data across a high-speed

link. Frames of different types are used by the LIP

and by the X.25 TIP. A frame provides high data

density in bit-serial format over data-grade lines.

Data assurance is also provided.

Frame (LIP) -

The basic communications unit used in trunk (NPU to

NPU) communications. Frames are composed of

control bytes, a CRC sum, and (in some cases) data

bytes in sub-block sequence. A sub-block may be a

block protocol block or a part of a block. Frames are

transmitted as a sequence of bytes through the mux

subsystem.

Frame (MUX) -

The mux subsystem uses a hardware-controlled frame

on the input and output mux loops.

Full Duplex (FDX) -

A transmission mode allowing data transfer in both

directions at the same time. An FDX system requires

a dual set of data lines, each set dedicated to

transmission in one direction only.

Function Codes -

Codes used by the service module to designate the

type of function (command or status) being

transmitted. Two codes are deﬁned: Primary

Function Code (PFC) and Secondary Function Code

(SFC). See Appendix C of the CCP System

Programmer's Reference Manual for deﬁnitions of

these codes.

FE-

Format Effectors. See below.

File-

A unit of batch data. Files are transferred between

application programs and terminals by using PRUBs on

the NPU's host side and transmission blocks on the

NPU's terminal side. A ﬁle contains one or more

records. Example: a card reader job can consist of a

ﬁle containing the card image records of all the cards

in the job deck.

File Registers -

The two sets of microregisters (ﬁle 1 and ﬁle 2) in the

NPU. File 1 registers contain parameter information

that is reloaded whenever the NPU is initialized.

Microprograms using ﬁle 1 registers may also change

values in them. File 2 registers are invariant

ﬁrmware registers that come preprogrammed with the

NPU.

Global Variables -

PASCAL variables which are deﬁned for use by any

CCP program. Contrast global variables with local

variables, which are identiﬁed only within a program.

Halt Codes -

Codes generated by the NPU when it executes a

soft-stop. These codes, which indicate the cause of

the stoppage, are sent to the host's engineering ﬁle. I

They are also contained in a CCP dump. |

Half Duplex (HDX) -

A transmission mode allowing data transfer in one

direction at a time. Normally a single set of data

lines carry input, output, and part of the control

information. Contention for use is possible in HDX

mode and must be resolved by the protocol governing

line transfers.

60471400 G C-3

HASP-

A protocol based on the BSC protocol; it is used by

HASP workstations. A workstation has both

interactive and batch devices. The standard code of

all HASP devices is EBCDIC; however, transparent

data exchanges with the host are also permitted. The

HASP TIP converts interactive HASP data between

EBCDIC transmission blocks and ASCn IVT blocks; it

converts batch HASP data between EBCDIC

transmission blocks and display code PRUBs.

Header -

The portion or portions of a message holding

information about the message source, destination,

and type. During network movement, a message can

acquire several headers. For example, during

movement of a message from a terminal to the host

over an X.25/NOS network, the message acquires the

following headers: one at the terminal (also a trailer),

one for the frame, one for the packet, and another for

the host block. Headers are discarded by the

appropriate stage of processing, so that in this

example, the host sees only the host block header.

Conversely, headers are generated and discarded as

needed downline, so that the terminal sees only the

terminal header (and trailer).

High-Speed Synchronous Line -

A data transmission line operating at or above 19,200

baud. These lines are normally used for local

LIP/remote LIP transfers and for PDN/NOS network

transfers.

HIP-

Host Interface Package. The CCP program which

handles block transfers across the host/local NPU

interface. The HIP transfers control blocks and data

blocks (IVT blocks or PRUBs).

Host-

The computer that controls the network and contains

the applications programs that process network

messages.

ID-

Identiﬁers. Identiﬁers can refer to port/subport,

nodes, lines, links, or terminals. Any hardware

element or connection can have an ID, normally a

sequentially assigned number.

Initialization -

The process of loading an NPU and optionally dumping

the NPU contents. After downline loading from the

host, the NPU network-oriented tables are conﬁgured

by the host so that all network processors have the

same IDs for all network terminals, lines, trunks, etc.

Input Buffer -

A data buffer reserved by CCP for receiving an upline

message for the host. These buffers are assigned and

released dynamically. Contrast with the CIB on the

mux subsystem interface.

Interface (NPU) -

The set of hardware and software that permits

transfers between the NPU and an external device.

There are three principal interfaces: to the host

through a coupler (block protocol in IVT or PRU

format handled by a HIP), to a neighbor NPU via the

mux subsystem (CDCCP protocol handled by a LIP),

and to the terminals (various protocols). Standard

terminal protocols are handled by the ASYNC, BSC,

MODE 4, HASP, and X.25 TIPs.

Interrupts -

A set of hardware lines and software programs that

allow external events to interrupt NPU processing.

Interrupting programs allow preferential processing on

a priority basis. The lowest priority level is processed

by an OPS monitor.

I V T-

Interactive Virtual Terminal. A block protocol format

for interactive terminals. CCP TIPs convert all upline

interactive messages to this format (exception: no

transformations are made to transparent data except

to put the messages into block format). By this

method, application programs in the host need only to

be able to process interactive data in IVT format

rather than in the multiplicity of formats that real

terminals use. Downline messages from the host to

interactive terminals (including virtual consoles) are

converted from IVT to real terminal format. IVT

processing is controlled by the TIPs; the TIPs use some

common IVT modules.

IVT Commands -

A group of commands that aUow the operator at the

terminal or a host application program to control some

of the IVT transforms made by a TIP. These

commands can (1) change the destination of the

terminal characters for breaks and cancel signals, (2)

select output page format (such as page width and

length, number of padding characters after a line feed

or carriage return), (3) designate parity type, terminal

class, and other terminal-related features.

LCB-

Line Control Block. A table assigned to each active

line in the system. It contains conﬁguration infor

mation as well as current processing information.

LCCB-

Logical channel control block. A data structure

holding information about logical channels. These are

used by the X.25 TIP for terminals connected to the

NOS network through a public data network.

Line-

A connection between an NPU and a terminal.

<SS53Sv

Link

A connection between two NPUs or an NPU and a

host. In release 3.1, a line which connects NPUs is the

same as a trunk.

L I P -

Link Interface Package. The CCP program which

handles frame transfers across a trunk; that is, across

the connection between a local and a remote NPU. A

LIP uses CDCCP protocol and interfaces on the local

NPU side to the HIP. On the remote NPU side, the

LIP interfaces with the appropriate TIP. In both local

and remote NPUs, the LIP interfaces with the mux

sub- system for transfer across the trunk.

LLCB-

Logical Link Control Block. A table assigned to each

logical link in the system which touches this NPU.

The table contains conﬁguration information as well

as current processing information.

Load -

The processing of moving programs downline from the

host and storing them in the NPU main and

micromemory. Loading of a remote NPU is

accomplished by the host through the use of overlays

in the local NPU.

C-4 60471400 G

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Local NPU -

An NPU which is connected to the host via a coupler.

A local NPU always contains a HIP for processing

block protocol transfers across the host/local NPU

interface.

Logical Connection -

A logical message path established between two

application programs or between a network terminal

and an application program. Until terminated, the

logical connection allows messages to pass between

the two entities.

Logical Line -

The basic message unit of a terminal. In most cases a

logical line is designated by a carriage return. See

Physical Line.

Logical Link -

See Link.

Local Operator (LOP) -

The operator of that terminal in the network that is

connecting a speciﬁc application program in the host

to the messages being processed. The terminal by

default is the host terminal, but the LOP can be

transferred to any other interactive terminal in the

network. The operator manages the communications

elements of the network within the local computer

system by communicating with the Communications

Supervisor in the host computer. Contrast with

network operator. The local operator is an

administrative operator within the network and need

not be the host computer's operating system operator.

Loop Multiplexer (LM) -

The hardware which interfaces the CLAs (which

convert data between bit-serial digital and bit-parallel

digital character format) and the input and output

loops.

Low/Medium-Speed Voice-Grade Line -

A line that operates at bit transmission rates at or

below 19,200 baud. These lines characteristically

connect individual terminals to an NPU or to a PAD

access device. Such lines can be either dedicated or

dial-up. Normal telephone lines operate in this

transmission range.

Main Memory -

The macromemory of the NPU. It is partly dedicated

to programs and common areas; the remainder is

buffer area used for data and overlay programs. Word

size is 16 data bits plus three additonal bits for parity

and program protection. Memory is packaged in 16K

and 32K word increments.

Mask-

A bit pattern used in the interrupt subsystem to check

if an interrupt is of sufﬁciently high priority to be

processed now. An interrupt mask (M) register is used

in this processing.

Message -

A logical unit of information, as processed by an

application program. When transmitted over a

network, a message can consist of one or more

physical blocks.

Mode 4 -

A communications line transmission protocol for

synchronous terminals. The protocol requires the

polling of sources for input to the data

communications network. CCP supports Mode 4A, 4B

and 4C terminals. Mode 4A equipment is polled

through a single hardware address (usually that of the

console device), regardless of how many devices use

the address as the point of interface to the network.

Mode 4C equipment is polled through several hardware

addresses, depending on the point each device uses to

interface with the network. The Mode 4 TIP processes

the interface between the NPU and the Mode 4

terminals.

Modem -

A hardware device for converting analog levels to

digital signals and the converse. Long lines interface

to digital equipment via modems. Modem is

synonymous with data set.

Micromemory -

The micro portion of the NPU memory. This consists

of 2048 words of 60-bit length. 1024 words are Read

Only Memory (ROM); the remaining 1024 words are

Random Access Memory (RAM) and are alterable. The

ROM memory contains the emulator microprogram

that allows use of assembly language.

Microprocessor -

The portion of the NPU that processes the programs.

MLIA-

Multiplex Loop Interface Adapter. The hardware

portion of the mux subsystem that controls the mux

loops (input and output) as well as the interface

between the NPU and the mux subsystem.

Module -

See program.

Monitor -

The portion of the NPU base system software

responsible for time and space allocation within the

computer. The principal monitor program is OPSMON,

which executes OPS level programs by scanning a

table of programs which have pending tasks.

Mux Subsystem -

The portion of the base NPU software which performs

multiplexing tasks for upline and downline data, and

also demultiplexes upline data from the CIB and places

the data in line-oriented data input data buffers.

NAM-

See Network Access Method.

Neighbor NPUs -

Two NPUs connected to one another by means of a

trunk. The NPU connected to the host via a coupler is

designated as the local NPU. The other NPU is a

remote NPU; it is not connected directly to the host in

any fashion.

Network -

An interconnected set of network elements consisting

of a host, one or more NPUs, and terminals.

60471400 G C-5

Network Access Method (NAM) -

A software package that provides a generalized

method of using a communications network for

switching, buffering, queuing, and transmission of

data. NAM resides in the host.

Network Deﬁnition Language (NDL) -

The compiler-level language used to deﬁne the

network conﬁguration ﬁle and local conﬁguration ﬁle

contents.

Network Logical Address -

The address used by block protocol to establish routing

for the message. It consists of three parts; DN - the

destination node, SN - the source node, and CN - the

connection number.

Network Operator (NOP) -

An administrative operator at the network operator

console. This terminal by default is the host console,

but the NOP function can be assigned to any other

| terminal in the system. The network operator

manages the NPU hardware, linkages, and other

network elements of the entire data communications

network by communicating with the Network

Supervisor in the network control center host

computer. Contrast with local operator. The network

operator can also be a local operator, but need not be

the operating system operator for the host computer

at the network control center.

Network Processing Unit (NPU) -

The collection of 255X hardware and peripherals

together with the software that includes Commu

nications Control Processor (CCP) macromemory

modules. These CCP programs buffer and transmit

data between terminals and host computer.

Network Supervisor (NS) -

A portion of the network software which coordinates

all of the NPUs in the communications network. NS is

written as an application program.

Node -

A network element that creates, absorbs, switches,

and/or buffers message blocks. Typical system nodes

are NS and CS in the host, the coupler node of a local

NPU and a terminal node of a remote NPU.

Off-Line Diagnostics -

Optional diagnostics for the NPU that require the NPU

be disconnected from the network.

On-Line Diagnostics -

Optional diagnostics for the NPU that can be executed

while the NPU is connected to, and operating as a part

of the network. Individual lines being tested must,

however, be disconnected from the network. These

diagnostics are provided if the user purchases a

network maintenance contract.

OPS Monitor -

The NPU monitor. See Monitor.

Output Buffer -

Any buffer which is currently used to output

I information from the NPU to another NPU or to a

terminal via the mux subsystem.

Overlay Area -

An area in upper main memory which is used to

execute overlay programs.

Overlay Programs -

Programs which are not normally resident in main

memory but which are called into the buffer area of

main memory to execute special tasks. These

programs are downline loaded (usually) from the host

and perform such tasks as NPU initialization

debugging, loading/dumping a remote NPU, and on-line

diagnostics.

Packet -

A group of binary digits, including data and call

control signals, which is switched as a single unit. The

data, control signals, and error-control information

are arranged in a speciﬁc format.

Packet Assembly/Disassembly (PAD) -

Assembly: The accumulation of characters from an

asynchronous device into data blocks for transmission

via a PDN. Disassembly: The encoding of blocks for

transmission to an asynchronous terminal.

PAD SubTIP -

A subTIP used with the X.25 TIP which allows a class

of asynchronous terminals to communicate over a

public data network.

Paging (NPU) -

A method of executing programs and accessing data in

the NPU main memory region above 65K. Paging is

required for addressing where the address is larger

than 16 bits (NPU word size) in length.

Paging (Screen) -

The process of ﬁlling a CRT display with data and

holding additonal data for subsequent displays.

Changing the paged display is an operator controlled

function if the page wait option is selected. |

Parity -

A type of data assurance. The most common parity is

character parity; that is, the supplying of one extra bit

per character so that the sum of all the bits in the

character (including the parity bit) is always an even

or odd number.

PASCAL -

A high level programming language used for CCP

programs. Almost all CCP programs are written in

PASCAL language.

PFC-

Primary Function Code. See Function Codes.

Physical Line -

A string of data that is determined by the terminal's

physical characteristics (page width or line feed).

Contrast with logical line, which is determined by a

carriage return or other forwarding signal.

Physical Link -

A connection between two major network nodes such

as neighboring nodes. Messages can be transmitted

over active physical links.

Polling -

The action of checking terminals to ﬁnd if an input

device is ready to transmit upline data. Certain TIPs

(such as Mode 4) poll terminal devices for data. The

host requests such polling; the TIP determines the

timing of the polling operation.

A ^ S \

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C-6 60471400 G

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Port (P) -

The physical connection in the NPU through which

data is transferred to/from the NPU. Each port is

numbered and supports a single line. Subports are

possible but not used in this version of CCP.

PPU (Peripheral Processing Unit) -

The part of the host dedicated to performing I/O

transfers. The coupler connects the PPU directly to

an NPU.

Priority Level -

A set of 17 levels of processing in the NPU. Priority

levels are interrupt driven. The OPS monitor

processes at the lowest priority level; that is, at a

level below any interrupt-driven level.

Program -

A series of instructions which are executed by a

computer to perform a task; usually synonymous with

a module. A program can be composed of several

subprograms.

Protect System -

A method of prohibiting one set of programs

(unprotected) from accessing another set of programs

(protected) and their associated data. The system uses

a protect bit in the main memory word.

Protocol -

The complete set of rules used to transmit data

between devices. This includes format of the data and

commands, and the sequence of commands needed to

prepare the devices to send and receive data.

PRU-

Physical record unit. A host batch ﬁle format. Batch

data is exchanged with the host in PRU block (PRUB)

format to minimize the amount of conversion a host

performs to make network data compatible with host

ﬁle handling capabilities.

PRU Commands -

A set of commands from the host or a terminal that

changes batch device or batch ﬁle characteristics,

alters batch data stream ﬂow, or transmits accounting

data to the host. All batch ﬁle and batch device

commands can come from the host. A few batch ﬁle

commands can also come from the terminal. Some

batch stream ﬂow commands come from the host;

others come from the terminals. Accounting data

commands come only from the terminals.

PRUB-

Physical record unit block. A block format for batch

terminals that is compatible with the host's PRU

(batch ﬁle) handling capabilities. CCP TIPs convert

all upline batch messages to this format (exception: no

transformations are made to transparent data except

to put the messages into PRUBs). By this method,

application programs in the host need only to be able

to process batch data in PRU format rather than in

the multiplicity of formats which real terminals use.

Downline messages from the host to real batch devices

are converted from PRUB to real terminal format.

PRUB processing is controlled by the TIPs with the

help of the BIP.

Public Data Network -

A network that supports the interface described in the

CCITT protocol X.25.

Queues -

Sequences of blocks, tables, messages, etc. Most NPU

queues are maintained by leaving the queued elements

in place and using tables of pointers to the next

queued element. Most queues operate on a

ﬁrst-in-ﬁrst-out basis. A series of worklist entries for

a TIP is an example of an NPU queue.

Record -

(1) A data unit deﬁned for the host record manager

(PRU); (2) a data unit deﬁned for HASP workstations.

In either case, a record contains space for at least one

character of data and normally has a header

associated with it. HASP records can be composed of

subrecords.

Regulation -

The process of making an NPU or a host progressively

less available to accept various classes of input data.

The host has one regulation scheme, the host and mux

interfaces of a local NPU have another scheme, and

the mux interface to a neighbor NPU has a third

regulation scheme. Some types of terminals (for

instance, HASP workstations) may also regulate data.

Data classiﬁcations are usually based on batch,

interactive, and control message criteria.

Remote NPU -

An NPU connected only to other (local) NPUs. A

remote NPU lacks a coupler; therefore it can have no

direct connection to the host.

Response Messages -

A subclass of service (network control) messages

directed to the host that are normally generated to

respond to a service message from the host. Response

messages normally contain the requested information

or indicate the requested task has been started/

performed. Error responses are sent when the NPU

cannot deliver the information or start the task. A

class of unsolicited response messages is generated by

the NPU to report hardware failures.

Routing -

The process of sending data/commands through the

NPU to the internal NPU process or to an external

device (for instance, a terminal). The network logical

address (DN, SN, CN) is the primary criterion for

routing. The NPU directories are used to accomplish

the routing function.

Service Channel -

The network logical link used for service message

transmission. For this channel, CN=0. The channel is

always conﬁgured, even at load time.

Service Message (SM) -

The network method of transmitting most command

and status information to/from the NPU. Service

messages use CMD blocks in the block protocol.

Service Module (SVM) -

The set of NPU programs responsible for processing

service messages. SVM is a part of the BIP. |

SFC-

Subfunction code. See Function Codes.

Source Node (SN) -

The network node originating a message or block of

information.

60471400 G C-7

State Programs -

Programs written in state programming language.

These programs usually are part of a TIP (some are

common to all TIPs), but do not operate on the OPS

level. Instead they are reached by a call to the mux

level or are operated automatically by the multiplex

subsystem. State programs process modem signals,

input data, and output data. Text processing is

primarily performed by state programs.

State Program Tables -

Tables used by the mux subsystem to locate the next

state program to execute.

Statistics Service Message -

A subclass of service messages that contain detailed

information about the characteristics and history of a

network element such as a line or a terminal.

Status -

Information relating to the current state of a device,

line, etc. Service messages are the principal carriers

of status information. Statistics are a special subclass

of status.

String -

A unit of information transmission used by the HASP

protocol. One or more strings compose a record. A

string can be composed of different characters or

contiguous identical characters. In the latter case,

the string is normally compressed to a single character

and a value indicating the number of times the

character occurs.

Subport -

One of several addresses in a port. In this CCP

conﬁguration, subport is always equal to 0.

Subprogram -

A series of instructions which are executed by a

computer to perform a task or part of a task. A

subprogram may be called by several programs or may

be unique to a single program. Subprograms are

normally reached by a direct call from a program.

Supervisory Message -

A message block in the host not directly involved with

the transmission of data, but which provides

information for establishing and maintaining an

environment for the communications of data between

the application program and NAM, then through the

network to a destination or from a source.

Supervisory messages may be transmitted to an NPU

in the format of a service message.

Switching -

The process of routing a message or block to the

speciﬁed internal program or external destination.

System Conﬁguration -

The process of setting tables and variables throughout

the network to assign lines, links, terminals, etc., so

that all elements of the network recognize a uniform

addressing scheme. After conﬁguration, network

elements accept all data commands directed

to/through themselves and reject all other data and

commands.

Terminal -

An element connected to a network by means of a

communications line. Terminals supply input messages

to, and/or accept output messages from, an

application program. A terminal can be a separately

addressable device comprising a physical terminal or

station, or the collection of all devices with a common

address.

Terminal Control Block (TCB) -

A control block containing conﬁguration and status

information for an active terminal. TCBs are

dynamically assigned.

Terminal Interface Packages (TIPs) -

NPU programs which provide the interface between

real terminal format and IVT or PRU format. The

standard TIPs are ASYNC, BSC, HASP, Mode 4, and

X.25 with PAD subTIP. TIPs are responsible for data

conversion and for some error processing.

Timeout -

The process of setting a time for completion of an

operation and entering an error processing condition if

the operation has not ﬁnished in the allotted time.

Timing Services -

The subset of base system programs which provide

timeout processing and clock times for messages,

status, etc. Timing services provide the drivers for

the real-time clock.

Trailer -

Control information appended to the end of a message

unit. A trailer contains the end-of-data control

signals. Trailers can be generated by the terminal or

by an intermediate device such as a frame generator.

Not all headers are matched with trailers, although

some devices split their control information between a

header and a trailer. The trailer usually contains a

data assurance ﬁeld such as a CRC-16 or a checksum.

Like headers, trailers are generated and discarded at

various stages along a message unit's path.

Transparent Mode -

A data mode in which the TIP minimally formats the

message and does no code translation. For most TIPs,

transparency can occur on both upline and downline

messages (ﬁles). If transparent mode is selected, the

entire message/ﬁle must be in the receiving device's

code and format (including all required header and

trailer information). In some cases, transparent mode

is speciﬁed by enclosing the message with transparent

delimiting characters; in other cases, the mode of

each ﬁle must be speciﬁed prior to beginning message

transmission.

Trunk-

A line connecting two NPUs or an NPU and a host.

The host/NPU trunk uses block protocol; the

NPU/NPU trunk uses trunk protocol.

Trunk Protocol -

The protocol used for communicating between

neighboring NPUs. It is a modiﬁed CDCCP protocol

which uses the frame as the basic communications

element.

C-8 60471400 G

TUP (Test UtUity Program) -

A debugging utility that supports breakpoint debugging

as well as other utility type operations such as loading

and dumping.

Typeahead (Terminal) -

The ability of a terminal to enter input data at all

times without losing output data currently in

progress. This requires suspending the output

operation until the input message is ﬁnished, and then

resuming the interrupted output. The ASYNC TIP

supports typeahead; the X.25 TIP supports typeahead

if it is provided by the PDN.

Unsolicited Service Messages -

Service messages sent to the host which do not

respond to a previous service message from the host.

Unsolicited SMs report hardware or software failures

to the host.

Upline -

The direction of message

through an NPU to the host.

travel from a terminal

Virtual Channel (X.25/PAD) -

A channel deﬁned for moving data between a terminal

and a host. Virtual channels are deﬁned for the

length of time that the terminal is connected to the

PDN.

Word-

The basic storage and processing element of a

computer. The NPU uses 16-bit word (main memory)

and 32-bit word (internal to the microprocessor only).

All interfaces are 16-bit word (DMA) or in character

format (mux loop interface). Characters are stored in

main memory two per word. Hosts (CYBER series) use

60-bit words but a 12-bit byte interface to the NPU.

Characters at the host side of the NPU host interface

are stored in bits 19 through 12 and 7 through 0 of a

dual-12-bit type.

Some terminals such as a HASP workstation can use

any word size but must communicate to the NPU in

character format. Therefore, workstation word size is

transparent to the NPU.

Worklists -

Packets of information containing the parameters for

a task to be performed. Programs use worklists to

request tasks of OPS level programs. Worklist entries

are queued to the called program. Entries are one to

six words long, and a given program always has entries

of the same size.

Worklist Processor -

The base system programs responsible for creating and

queuing worklist entries.

X.25 Protocol -

A CCITT protocol used by the public data network. It

is characterized by high-speed, framed data transfers

over links. A PDN requires a PAD access for

attaching asynchronous terminals.

X.25 TIP -

The CCP TIP that interfaces an NPU to a public data

network.

J0&&*.

60471400 G C-9

CCP MNEMONICS

| ACK0/ACK1 Acknowledge Block (BSC/HASP protocol) CMDR

ACN Application Connection Number CN

ACTL

1APL

Assurance Control Block CND

A Programming Language CR

ARM Asynchronous Response Mode CRC

ASCII American Standard Code for Information CRT

Interchange CS

ASYNC Asynchronous

BACK Acknowledgment Block CTL

BCB Block Control Byte (HASP protocol) DBC

| BCD Binary Coded Decimal DCB

BFC Block Flow Control DDLT

BFR Buffer DEL

| BIP Block Interface Package DM

BLK Message Block DMA

BN Block Number (overlay) DN

BRK Break Block DND

| BSC Binary Synchronous Communication DSR

BSN Block Serial Number (for blocks/SVM) DT

1Bl, B2

Block Type EBCDIC

User deﬁned breaks for HASP (protocols and

other) EC

CA Cluster Address E-CODE

CB Control Block ENQ

CCITT Comite Consultif International Telephonique

et Telegraphique (an international com

munications standards organization)

EOF

EOI

CDCCP CDC Communications Protocol (trunk EOJ

protocol) EOM

CDT Conversational Display Terminal EOR

ETB

CCP Communications Control Program (in NPU)

CE Customer Engineer

ETX

CFS Conﬁgurator State (for SVM) FCD

CIB Circular Input Buffer

FCS

CLA Communications Line Adapter FD

CMD Command Block

Command Reject (trunk protocol)

Connection Number (for blocks/SVM)

Connection Number Directory

Carriage Return

Cyclic Redundancy Check

Cathode Ray Tube

Communications Supervisor Program (in

host)

Control Element (ASYNC protocol)

Data Block Clariﬁer (for blocks/SVM)

Diagnostics Control Block

Diagnostic Decision Logic Table

Delete Character

Disconnect Mode (trunk protocol)

Direct Memory Access (in NPU)

Destination Node (for blocks/SVM)

Destination Node Directory

Data Set Ready

Device Type

Extended Binary Coded Decimal Interchange

Code

Error Code

Device Codes (MODE 4 protocol)

Enquiry Block (BSC/HASP protocol)

End of File

End of Information

End of Job

End of Message

End of Record (HASP protocol)

End of Transmission Block (HASP protocol)

End of Text

First Character Displacement (in buffer)

Function Control Sequence (HASP protocol)

Forward Data (block protocol)

60471400 G D-l

FDX Full Duplex LLREG

FE Format Effector LM

FF Forms Feed LOP

FN Field Number (for SVM) LP

FRQ Frame Retention Queue (trunk protocol) LRN

FS Forward Supervision (block protocol) LT

FV Field Values (for SVM protocol)

HASP Houston Automatic Spooling Protocol MLCB

HCP Host Communications Processor (alternate

name for NPU) MLIA

HDLC High Level Data Link Control

MPLINK

HDX Half Duplex

MSG

HIP Host Interface Package

MTI

HL High Level

HO Host Ordinal

NAK

IAF Interactive Facility Program (in host)

1 ICMD Interrupt Block NAM

1 ICMDR Interrupt Response Block NCF

ID Identiﬁer (number of code)

NDA

IDC Internal Data Channel (in NPU)

NDLP

I-FRAME Information Frame (for trunk protocol)

NHP

INIT Initialization Block

NIP

I/O Input/Output

NOP

ISO International Standards Organization

NPINTAB

IVT Interactive Virtual Terminal Format

NPU

LBN Last Block Number (overlay)

LCB Line Control Block (in NPU)

NVF

| LCCB Logical Channel Control Block (in NPU)

ODD

LCD Last Character Displacement (LCD)

OPS

LCF Local Conﬁguration File (in host) (CS

controlled)

OPSMON

LD Load/Dump

LF Line Feed

PAD

LIDLE Idle Element (trunk protocol)

PCB

UNIT Line Initialization Element (trunk protocol)

PDN

LIP Link Interface Package (in NPU)

PFC

LL Logical Link

LLCB Logical Link Control Block (in NPU)

Logical Link Regulation

Loop Multiplex

Local Operator

A series of TUP commands start with *LP

Link Remote Node (for SVM)

Line Type

Mask Register

Mux Line Control Block

Mux Loop Interface Adapter

Main Memory

The PASCAL Linking Editor

Message Block

Message Type Indicators (MODE 4 protocol)

MODE 4

Negative Acknowledgment Block (BSC/ I

HASP protocol) |

Network Access Method Program (in host)

Network Conﬁguration File (in host) (NS

controlled)

Network Dump Analyzer (in host)

Network Deﬁnition Language (for host)

Network Host Products

Network Interface Program

Network Operator

NPU Table

Network Processing Unit

Network Supervisor Program (in host)

Network Validation Facility (in host)

Output Data Demand (Mux subsystem)

Operational (OPS level = Monitor level

programs)

Monitor

Port

Packet Assembly/Disassembly

Program Control Block

Public Data Network |

Primary Function Code (for SVM)

Page Length (IVT)

4^tWSS

>5^V

D-2 60471400 G

PPU Peripheral Processing Unit (in host)

PRU Physical Record Unit

PRUB Physical Record Unit Block

PW Page Width (IVT or PRU)

QCB Queue Control Block

QDEBUG PASCAL Debugging Package

RAM Random Access Memory

RBF Remote Batch Facility Program (in host)

RC Reason Code (for SVM) (also called response

code)

RCB Record Control Byte (HASP protocol)

RCV Receive State

| REJ Reject (trunk or X.25 protocol)

RIM Request Initialization Mode (trunk protocol)

RL Regulation Level

RM Response Message (SM)

RNR Receive Not Ready (trunk or X.25 protocol)

RR Receive Ready (trunk or X.25 protocol)

RS Reverse Supervision (block protocol)

RST Reset Block

R T R e c o r d T y p e

RTS Ready to Send (trunk protocol)

ISA R M Se t A s y n chron o u s M o d e ( t r u n k or X . 25protocol)

SCB String Control Byte (HASP protocol)

| S-FRAME Supervisory Frame (trunk or X.25 protocol)

SFC Secondary Function Code (for SVM)

SIM Set Initialization Mode (trunk protocol)

SM Service Message

SN Source Node (for blocks/SVM)

SND Source Node Directory

SP Support

SRCB Subrecord Control Byte (HASP protocol)

S T P S t o p D a t a B l o c k

STRT Start Data Block

STX Start of Text (ASYNC protocol)

SVM Service Module for Processing Service

Messages

SYNC Synchronizing Element (MODE 4 protocol)

TA Terminal Address

TAF Tr a nsacti on Facili t y ( in host)

TC Terminal Class

TCB Terminal Control Block (in NPU)

TDP Time Dependent Program

TIP Terminal Interface Package (in NPU)

TIPTQ TIP Trunk Queues (trunk protocol)

T O T i m e o u t

TOT Total Number of Trunks (SM)

TPCB Text Processor Control Block

TT Terminal Type

TTF Trunk Transmission Frame

TTY Teletype (asynchronous device)

TUP Test Utility Program

TVF Terminal Veriﬁcation Facility (in host)

UA Unnumbered Acknowledgment (trunk or

X.25 protocol)

U-FRAME See UA and UI

UI Unnumbered Information Frame (trunk or

X.25 protocol)

US Unit Separator

UT User Terminal

VAR PASCAL Variable

WL Worklist

WLCB Worklist Control Block

WLE Worklist Entry

WLP Worklist Processor

X-OFF Stop Punch Character (ASYNC protocol)

X-ON Start Punch Character (ASYNC protocol)

X P T Tran s p a r e nt B it , p a p e r t a pe ( AS Y N C T IP )

X.25 CCITT Protocol for Public Data Network

X.28 CCITT Protocol for Terminal Access to

PDN/PAD

X.29 C C I TT Pro t o c ol f o r h o s t a c c ess t o P D N / PA D

X.3 CCITT Protocol for Asynchronous Terminal

Access to a PDN

60471400 G D-3

SAMPLE MAIN MEMORY MAP FOR NPU

Figure E-l shows the locations of the principal CCP program groups in a 255x network processor unit with 96K words of

memory. It is assumed that this is the smallest memory size that will be used with PRU, the HIP, a LIP, and at least one TIP.

Note that the HIP, LIP, BIP, and all TIPs are paged. It is assumed that the standard build procedures described in the CYBER

Cross Build Utilities Reference Manual and in the NOS Installation Handbook are being used. Therefore, the user need not be

concerned with assigning modules to the various regions shown here. Autolink automatically optimizes the amount of memory

left for message processing buffers. (Autolink is described in the CYBER Cross Build Utilities Reference Manual.)

The example shown is an autolink generated load ﬁle for a local NPU (which requires a HIP and BIP) and three options: a LIP,

the Mode 4 TIP, and the HASP TIP.

0*9*S

Locations

in Hexadecimal

0000

0100

0140

0150

0DAOT

ifaeT

2000

4000

8B83t

D897T

D8AF*

FFFF

10000

12000

14000

16000

Jump to BEGINX

Interrupt trap locations

Jump locations

Address table

PASCAL globals

Some base routines

BIP modules assigned to this area. HIP, LIP, TIP

and other BIP modules assigned to pages above

FFFF have their addresses imaged to this 2K

(hex) page.

Base routines, mux routines, and routines asso

ciated with paged applications above FFFF are

loaded in this base area by Autolink. Parts of

TIPs that must be in base are always loaded in

this region.

ID table - must be last base application

(see Autolink directives)

Start of the initialization programs

Initialization routines

Mode 4 TIP

HASP TIP

LIP and HD?

BIP

Program Name

ZEROX

PBINTRP

JUMPS

ADDRES

GLOBL$

(hex)

page of

memory

Base region

PIDTBL

main$ \ Reserved by autolink

BEGINX

for buffers

Area released for use

as buffers after initialization

There is some mixing of

modules from one application

on the page assigned to another

application. See autolink

directives in the CYBER Cross

Build Utilities Reference Manual

'These addresses can ﬂuctuate because of local mods, TIP selection differences, and PSR level.

Figure E-l. Sample CCP Memory Map

60471400 G E-l«

■{*%

CCP NAMING CONVENTIONS

The following naming conventions for the CCP PASCAL

programs should be regarded as guidelines rather than as

strict requirements.

The general format of a label is:

PIRRRRSSS

Where the usual length is six bytes, but additional bytes can

be used.

P values are: A-0 Global data

PProcedure or function

Q- W Local data

X -Z NonC DC

I values are: Transparent or not tied down

1 -9 Not a structure

A-Z A structure

For prccedures and functions:

P = P, I = Assurance programs

Base system or BIP programs

Diagnostic programs

Mux subsystem programs (part

of the base system)

Network Communications

programs

Packets

TIPs, HIP, LIP

For types, variables, ﬁelds, etc.

BA... Overlay

BF... Buffer

EL Logical Link Control Block (LLCB)

DS... Terminal CB(TCB)

BW... Intermediate array for Worklist

BY... Uciklist CB(WLCB)

BZ... Line CB (LCB)

D... Service Module

J... Input/Output (I/O)

JU... TUP table

LD... Lojtd/dump

M... Mux subsystem

MM... Event interface

N... Mux subsystem

NC... Mux Line CB (MLCB) or Test Proce

CB (TPCB)

NK... Mux command driver inputs

NZ... Diagnostics CB (DCB)

60471400 G F-l

'""^

!^%

TERMINAL COMMANDS AND MESSAGES

TERMINAL MESSAGES

All interactive terminals controlled by the NPU receive

Preformatted messages when the host becomes unavailable,

and when the host is again available. A few output batch

devices also receive these messages. The messages are:

• Host unavailable message:

HOST UNAVAILABLE

Reply to a message sent upline to a host after the

host unavailable message has been sent to the

terminals:

INPUT DISCARDED

Host again available message:

INPUT RESUMED

INTERACTIVE TERMINAL COMMANDS

An interactive terminal has a limited ability to alter

certain IVT processing parameters. A summary of these

alterable parameters is shown in ﬁgure G-l.

The general format of the command message that changes

these parameters is:

CTL1 PARAMETER COMMAND CTL2

where CTL1 and CTL2 are the terminal's normal starting

and ending characters to delimit messages. Each

parameter command has the form of two characters

followed by an equals sign followed by the selected value:

xx = value

If a TIP accepts the command, the TIP does not usually

send a positive acknowledgment to the interactive device.

However, if the TIP rejects the command (as in the case of

a command that is invalid for the type of terminal being

used), an error message is returned to the operator. The

error message has the form:

ERR...

Table G-l shows the IVT commands that can be entered

from each type of terminal.

- 17 «

PW < NNN>

PL <NNN>

P A =

C N =

BS =

C T »

C l =

L l =

SE =

D L -

I N =

OP =>

[i]

< SELECTED CHAR >

rcA-i

L<NN>J

l-CA-l

L< NN >J

[:]

(X<HH» (,C<NNNN» (.TO)

[5]

PG [ s ]

AL < SELECTED CHAR >

B1 < SELECTED CHAR >

B2 <SELECTED CHAR >

MS <TEXT>

Figure G-l. Summary of IVT Commands

Entered From a Terminal

60471400 G G-l»

TABLE G-l. TERMINAL PARAMETERS AS USED BY STANDARD TIPS

Conmand MD4 BSC HASP ASYNC X.25 with PAD

TC Terminal Class A R t t A R t t AR

PW Page Width AR AR AR AR

PL Page Length AR AR AR

PA Parity

CN Cancel Input Line Chain

BS Backspace

CT Control Character

CI CR Idle Count

LI LF Idle Count

SE Special Edit Mode A .

DL Transparent Delimiter A/Bttt A/Bt A/I§§

IN Input Mode

OP Output Mode

CD Character Set Detect A§

EP Echoplex Mode

PG Page

AL Abort Output Line

Bl User Break 1

B2 User Break 2

MS Message to Operator

Other or Invalid Parameters

ATake the comnanded action

AR Take the commanded action and report to CS

BNo action; send BRK block to host and ERR... message to terminal

CValid only from user

IIgnore

'These commands are valid only for certain terminal classes. DL is not a valid command for

terminal class 4 (IBM 2741). A BRK block will be sent to the application if any of these

commands are received for a terminal in a class which does not support the command.

'•An error will occur for any attempt to change mode between subTIPs. For ASYNC, terminal class

4 is not allowed if the extended ASYNC feature is not conﬁgured.

TTlTransparent mode can be used only on mode 4C devices.

'The command is legal only if the NPU is conﬁgured to support the extended ASYNC feature.

Otherwise, CCP sends BRK or ERR... message to the terminal.

§SOnly the K, X, and KX options are allowed.

PARAMETER COMMAND DEFINITIONS

Terminal parameter deﬁnitions are:

• Terminal Class (TC)

TC establishes a class for the terminal with

default values for all parameters as deﬁned in

table E-7. A TIP will not execute the command if

the class is not supported. This change must be

reported to CS in the host.

• Page Width (PW)

PW establishes the physical line width in charac

ters for output. For non-transparent blocks, the

TIP inserts the character sequence deﬁned for the

terminal class to move the carriage or cursor to

the next line at the point where the number of

characters to be transmitted equals the page

width. The parameter NNN varies between 0 and

255; 0 means "new line" and is never inserted.

This change must be reported to CS in the host.

Page Length (PL)

PL establishes the number of physical lines in a

page for output. The TIP inserts the character

sequence deﬁned for the terminal class to

advance the carriage or cursor to the next page

length. Also, if the page wait feature is selected,

the TIP will wait for an operator input before

continuing. The parameter NN varies between 0

and 255; 0 means no paging. This change must be

reported to CS in the host.

NOTE

None of the remaining IVT parameter

changes need be reported to the host (CS).

Parity Selection (PA)

PA speciﬁes the type of parity which the TIP

expects on input and generates on output. See

description of parity in the asynchronous TIP

section of this manual.

• G-2 60471400 G

>«S5V

• Cancel Character (CN)

CN establishes the character which is used to

delete the current logical input line. If special edit

mode is engaged, the CN character is treated as

data and is sent to the host; the delete action is not

performed.

• Backspace Character (BS)

BS establishes the character which is used to delete

the previous input character from the current input

buffer. If special edit mode is engaged, the BS

character is treated as data and is sent to the host;

the backspace action is not performed.

• Control Character (CT)

CT establishes the character which is used to enter

operational control messages.

• Carriage Return Idle Count (CI)

CI establishes the number of idle characters to be

inserted in the output stream following carriage

return (CR). The use of Cl-nn overrules the default

value and CI-CA restores the default value.

• Line Feed Idle Count (LI)

LI establishes the number of idle characters to be

inserted in the output stream following line feed

(LF). The use of Ll-nn overrules the default value

and LI-CA restores the default value.

• Special Edit Mode (SE)

A SE = Y selection places the terminal in special

edit mode; an SE = N selection returns the terminal

to the normal character edit mode. Special edit

mode provides two types of special operations:

(1) backspace (BS), linefeed (LF), and cancel input

control symbols are not treated as control

characters by the TIP; instead, they are sent

upline as data.

(2) a character delete sequence (one or more

backspaces followed by a linefeed) causes the

TIP to issue a caret prompt to the terminal,

and then to continue with input processing.

• Transparent Text Delimiter (DL)

DL establishes the transparent text delimiter for

input. The delimiter may be a character, a

character count or a timeout of 300 ± 100 ms. One

or more of the delimiters may be active

simultaneously.

• Input Device (EN)

IN speciﬁes the input device as a keyboard or paper

tape reader in character or transparent mode.

Note that paper tape input is allowed in keyboard

mode, but that the TIP does not send the < X-ON>

characters to start the paper tape reader.

• Output Device (OP)

OP speciﬁes the output device as printer, CRT

display, or paper tape punch. Printer and CRT

display are functionally equivalent. The user may

punch a paper tape in any mode, but the TIP

provides the X-OFF character only if OP=PT and if

data is not transparent.

• Character Set Detect (CD)

This restarts the character set recognition logic

when changing a character set during a message

exchange sequence. First, the terminal operator

enters the IVT command: CD = A. Then the

operator has 60 seconds to (1) physically change the

terminal's code set (for instance, by changing the

type element on a typewriter), and (2) activate the

TIP's code set recognition sequence by pressing the

carriage return key.

• Echoplex Mode (EP)

EP speciﬁes where input character echoing will

take place. EP=N implies the terminal is doing its

own input echoing and EP=Y causes the TIP to set

the CLA to provide character echoing.

• Page Wait (PG)

PG selects the page wait feature. It allows the

user to control output by demanding each page

explicitly after the previous page has been viewed

for the desired period of time.

• Abort Output Line Character (AL)

AL selects the character which, when input

followed by a carriage return, will result in the

current output line being discarded.

• User Break 1 (Bl)

Bl selects the character which, when input

followed by a carriage return, will cause the TIP to

send an upline BRK block with reason code

specifying "user break 1". Conventionally user

break 1 is used to abort the queue.

• User Break 2 (B2)

B2 selects the character which, when input

followed by a carriage return, will cause the TIP to

send an upline BRK block reason code specifying

"user break 2". Conventionally user break 2 is used

to abort the job.

NOTE

At 2741 terminal, when an operator

uses a break 1 or break 2 character, he

must precede it by an ATTN character.

• Message (MS)

MS deﬁnes the character used to delimit messages

to the LOP.

ym«s 60471400 G G-3 •

BATCH TERMINAL FILE (transparent/non-transparent) by entering information in /^S

CHARACTERISTIC COMMANDS columns 79/80 of aJ'ob or E0R card-

In the current release only the BSC and HASP batch • 26 selects 026 mode

terminals can send requests to the host remote batch

facility (RBF) to change the operating charcteristics of • 29 selects 029 mode

batch ﬁles. • TR selects transparent mode (used on EOR card

A BSC/HASP card reader can change the card punching only; the terminal transparent switch must be on

characteristics (026/029) or the device data mode when this card is read)

/rf^^S

• G"4 60471400 G

NPU OPERATING INSTRUCTIONS

yss

Except for the diagnostics which are described elsewhere,

the only operator actions that might be needed at the NPU

concern loading the system. Even these actions are needed

only in exceptional conditions, since once CCP has been

successfully loaded, the host should control all subsequent

load operations automatically. Nonetheless, following a

failure, it may be desirable to check NPU control switch

positions and initiate a CCP load manually.

LOCAL NPU PROCEDURE

To prepare for a downline load, the NPU operator should

perform the following steps:

1. Verify that ports (CLA addresses) to the

communications network are correct.

2. On loop multiplexer circuit card, set power (PWR)

switch to ON. See ﬁgure H-l.

3. On CLA circuit card, set CLA/OFF switches to

CLA (on). See ﬁgure H-2. Only those cards that

are conﬁgured are affected.

4. Verify that local console is in normal ON

condition.

5. Stop the NPU at the maintenance panel by

pressing the MASTER CLEAR switch (ﬁgure H-3).

The host discovers that NPU has stopped and initiates the

dump and reload sequence.

Upon successful completion of the downline load operation

by the host, the host is notiﬁed. The host then conﬁgures

the NPU terminals and normal system operation begins.

If the downline load is unsuccessful, the host initiates and

receives a dump of the NPU memory, micromemory

checksum, and ﬁle 1 registers. The initiation of another

downline load attempt is under control of the host.

REMOTE NPU PROCEDURE

The procedure for the remote NPU is the same as that for

the local NPU except for the following:

• Check bootstrap load (SAM-C) tape equipment

mounted on NPU cabinet door. The SAM-C tape

cassette should be loaded and the ENABLE/

DISABLE switch should be set to ENABLE.

• The NPU is downline loaded via a local NPU.

60471400 G H - l •

I ■

LCLKIO

AT O

TCLKjO

kDAllo

<2>

OFF

PWR

POWER

ON/OFF

SWITCH

o -

CLA 1

ON/OFF

SWITCH

CLA 2

ON/OFF

SWITCH

CLA1

OFF

! ;i

RTS

LPCD

r sd

£ RD

A RTS

f S D

L RO

CLA 1

ADDRESS

SWITCHES

CLA 2

CLA2

<§)

OFF

-®

li!

Figure H-l. Loop Multiplexer Circuit Card

PWR ON/OFF Switch Location Figure H-2. CLA Circuit Card ON/OFF

Switch Locations

H-2 60471400 G

Uio h®

ooO

oo□

« § - 8 - 8 - 1

©© 0 ®

©©© ®

©©©©

©Q 0 8

rZ J 5 5 8 ' * ' . ?

t+ Z i

z *

8-liiiil?E

-«=■««.--.

~ j < < ; . .' J

soooo 0001 0010 0100 0101 0110 om

§>

60471400 G H-3*

INDEX

Address table B-10

Alarm messages B-l

ASCII A-l

Async TIP 1-13, 2-20

Base system 1-7,1-10, 2-5

BIP 2-8

Block

Interface Package (BIP) 2-8

PRU 2-2

Routing 2-2

Breakpoint 1-18

Buffers 2-1, 2-5

Card reader 2-21, 2-23, 2-24, 2-29

Cassette 1-18, 3-1

CCP 1-1, 1-6,1-7

CCP coding languages 1-7

CE error messages B-l

Character sets A-l

CLA 1-7,1-19

Common TIP subroutines 2-9

Communications

Control Program (CCP) 1-1, 1-7

Network products 1-6

Processor (NPU) 1-17

Supervisor (CS) 1-4

Computer network 1-1

Conﬁguration 1-19

Conﬁgure NPU 3-7

Control blocks 2-5

Control words 2-12

Coupler 1-19

CS 1-4

CYBER Cross Build Utilities 1-16

Data

Block 2-28

Conversion 2-1, 2-23

Downline 2-37

Transfer 1-7, 2-18

Upline 2-36

Demultiplexing 2-7

Diagnostics 1-7, 2-10, 4-1, appendix B

Direct program calls 2-6

Dump see Load/dump

Errors 2-28

HALT codes B-8

Hardware 1-6, 1-17, 2-4

HASP 2-27

HIP 1-11, 2-11

Host

Failure 2-10

Interface 1-11, 2-11, 2-22

Regulation 2-35

IAF 1-4

Initialization 2-4, 3-1

Input

Processing 1-7, 2-7, 2-20, 2-22, 2-25, 2-29, 2-31

Regulation 2-35

Interactive Facility (IAF) 1-4

Interface Packages 2-11

Hardware 2-11

Software 2-8, 2-10, 2-11

Interfaces 1-7, 2-3, 2-22

Internal processing 2-9

Interrupts 1-18, 2-6

IVT 1-9, 1-11, 2-19

Languages 1-7, 1-15

Line failure 2-10

LIP 1-9, 1-10, 1-12, 2-10, 3-6

Load/dump

Dump format B-12

Local NPU 2-11, 3-1

Remote NPU 1-13, 2-11, 3-2, 3-6

Logical link failure 2-10

Logical link regulation 2-36

Loop multiplexer 1-18

Macro assembler 1-15, 1-17

Message

Movement 1-7

Processing, input 1-7

Processing, output 1-8

Micromemory 1-11, 2-12

MLIA 1-18

Mode 4 1-13, 2-21

Monitor 2-5

Multiplex Loop Interface Adapter (MLIA) 1-18

Multiplex subsystem 1-18, 2-7

Multiplexing

Input 1-10, 2-1, 2-7

Output 1-10, 2-1, 2-7

Trunk 1-10, 2-7

Failure

Host 2-10

Line 2-10

Logical link

NPU 2-10

Terminal 2-10

Trunk 2-10

Globals 2-7

2-10

NAM 1-2 thru 1-5

NDL 1-4

Network

Access Method (NAM) 1-2

Communications 1-1

Communications software 1-7, 2-8

Computer 1-2

Concepts 1-1

Deﬁnition Language (NDL) 1-4

Message movement 1-7

60471400 G Index-1 •

Operating System (NOS) 1-2

Processing 1-9

Supervisor (NS) 1-4

NPINTAB B-ll

NPU

Conﬁguring 3-7

Description 1-1,1-6,1-12,1-17, 2-1

Failure 2-10, 4-1

Load/dump 2-18, 3-1, 3-6, B-12

Memory 1-6,1-11,1-17,1-18

Remote 1-12, 2-19

NS 1-4

ODD 1-10

Operating procedures H-l

OPS monitor 2-5

Output 1-18

Output processing 1-8, 2-7, 2-21, 2-23, 2-25, 2-29, 2-30

PASCAL 1-15

PPU 2-11

Printer 2-24, 2-26

Priorities 1-12, 2-33

Program protection 1-18

Protocol

ASYNC 1-13,2-20

Block 2-9

BSC 1-13,2-24

HASP 1-14,2-27

Mode 4 1-13,2-21

X.25 1-15, 2-30

Service module 2-9

Standard subroutines 2-7

State programs 1-17

Statistics message B-6

Status words 1-12, 2-18

Switching 2-1

System monitor 2-5

TAF 1-4

Terminal

Commands H-l

Failure 2-10

Interface Packages (TIP) 1-13, 2-19

Parameters H-l

Regulation 2-35

Terminal Veriﬁcation Facility (TVF) 1-5

Timing services 2-6

TIPs

ASYNC 1-13, 2-20

BSC 1-13, 2-24

Functions 2-12, 2-13, 2-19

HASP 1-14, 2-27

MODE 4 1-13,2-21

Non-standard 1-15

Subroutine (common) 2-9

X.25 1-15, 2-30

Transaction Facility (TAF) 1-4

Transmission

Assurance 2-18

Media 2-3

Trunk

Regulation 1-12, 2-19

Transmission priorities 1-12, 2-19

TVF 1-5

Queuing 2-6

UPDATE 1-16

User interface 2-21

RBF 1-4

Recovery 2-10, 4-1

Regulation

Host 2-35

Logical link 2-36

Terminal 2-35

Trunk 2-35

Remote Batch Facility (RBF)

Routing 2-9

Virtual terminals 2-9

Worklists 2-5

X.25

1-4 Input sequence 2-30

Output sequence 2-30

TIP with PAD subTIP 1-15, 2-30

• Index-2 60471400 G

00m\

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