Texas Instruments DS990 Configuration guide

Commercial Computer Systems
General Information
'IEXt\S INSIRUMENTS.

DS990
Commercial
Computer Systems
General Information
Published by
~ TEXAS INSTRUMENTS
~ INCORPORATED

Copyright@ 19-7-8-by Texas Instruments incorporated. AItRrghts
Reserved. Printed in the United States of America.
No part of this publication may be reproduced, stored in a retrieval
system, or transmitted in any form or by any means, electronic,
mechanical, photocopying, recording, or otherwise, without the prior
written permission of Texas Instruments Incorporated.
Texas Instruments reserves the right to make changes at any time to
improve design and supply the best product possible.
The information in this document is subject to change without notice
and should not be construed as a commitment by Texas Instruments
Incorporated. Texas Instruments assumes no responsibility for any
errors that may appear in this document.
1st Edition, July 1978
Texas Instruments Incorporated
Digital Systems Division
P.O. Box
2909
Austin, Texas 78767

Table of Contents
OS990 Commerciai Systems Overview
Page
DS990 Software ............................ 2
DX10 Operating System
..................... 2
File Management
.......................... 2
Error Control and System Log
................. 3
High-Level
Languages and Utilities .............. 3
Program-Development Tools
.................. 3
Communications Software
.................. .4
DS990 Hardware ............................ 4
990 Processor. . . . . . . . . . . . . . . . . . . . . . . . . . . .4
TILINE Peripherals ....................... .4
CRU Peripherals ......................... .4
Communications Equipment and Special
Interface
Devices .......................... 5
990 Chassis Considerations ................... 5
Customer-Support Services
..................... 5
08990 Software
Page
DX10 Operati ng System. . . . . . . . . . . . . . . . . . . . . . .7
System Generation ........................ 8
Program Management
....................... 8
Memory Management
...................... 10
System Command Interpreter
................ 10
File Management ........................... 13
File Types
............................. 13
File Features
........................... 13
Physical Disk Characteristics
............•.... 15
Logical
Input/Output ...................... 15
Error Control
and System Log .................. 16
High-Level
Languages and Utilities ............... 17
COBOL ............................... 17
RPG II ............... " ...... " " .... 20
DBMS 990
............................. 21
BASIC ............. " ................. 22
FORTRAN
............................ 27
Pascal ................................ 29
Sort/Merge. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
31
Program-Development Tools ................... 31
Interactive Text Editor. .................... 31
Macro Assembler ......................... 31
Link Editor ............................ 32
Debug
Package .......................... 32
Communications Software
.................... 32
Features of 3780 Emulator .................. 33
Comparison with IBM 3780
.................. 33
Control ............................... 34
System Requirements ...................... 34
Components
of 3780 Emulator ............... 34
Customer Information
..................... 35
DS990 Hardware
Page
990 Processor ............................. 37
990 Architecture ......................... 39
Interrupt Structure ...................... .40
990 Address Space ........................ 40
Instruction Set and Addressing Modes
........... 41
990 CPU On-Board Loader .................. 42
Programmer
Panel ........................ 42
990 Memories ........................... 42
990 TILINE ............................ 43
Communications Register
Unit ................ 43
TI LINE Peripherals ......................... 43
Model
DS31 Disk System ................... 44
Model OSlO Disk System
.................. .45
Model DS25 and Model DS50 Disk System ....•... 46
Model 979A Magnetic-Tape Transport
....•...... 47
CRU Peripherals ........................... 47
Model
911 Video Display Terminal ............. 47
Model 810 Printer
........................ 50
Model 2230 and Model 2260 Line Printers ........ 50
Model 733 ASR Data Terminal ............... 51
Model 743 KSR Data Terminal ....•.......... 52
Model 804 Card Reader
.................... 52
Model FD800 Floppy-Disk System
............. 52
Communications Equipment
................... 53
Special Interface Devices ...................... 54
EIA Data Modules ........................ 54
TTL Data Modules ........................ 54
TTY /EIA Terminal Interface Module .......•... 54
32-Bit Input!Transition Detection Module
........ 54
32-Bit Output-Data Module
.................. 54
Digital-I/O-Termination-Panel Module
........... 55
D/A Converter Modules .................... 55
A/D Converter Modules .................... 55
990 Chassis Considerations .................... 55
Standard
Chassis Configuration in DS990 Systems ... 56
Dc-Power Considerations
................... 56
CRU and TILINE I/O Expansion .............. 57
Customer-Support Services
Page
Hardware Installation ........................ 59
Software Installation
........................ 59
Hardware Maintenance
.•..................... 59
Maintenance Agreement
...................... 59
On-Call Service . . . . . . . . . . . . . . . . . . . . . . . . . .60
Fixed-Price Repair Service ................... 61
Software Update ........................... 61
Education Classes .......................... 62
Customer-Support Line
(Hot Line) ..............• 62

Appendixes
A!'pendix Page
A SC I Commands ........................ 63
B 990 Instruction Set ..................... 63
C Memory Requirements ................... 63
o Recommended Memory and Disk Configurations .. 70
E Disk Requirements ..................... 71
F Chassis Planning ....................... 71
Chassis-Power Planning ................. 72
Chassis-Layout Planning ................ 73
G Cabinet Planning ....................... 75
Enclosures ......................... 75
Cabinet-Layout Worksheet .............. 79
H DS990 System Kit Contents ............... 81
I Equipment Specifications ................. 81
J Packing and Shipping .................... 81
K Documentation. . . . . . . . . . . . . . . . . . . . . . . .83
Hardware Manuals
.................... 83
Software Manuals .................... 84
List of Illustrations
Figure
Page
DS990 Model 4 System and Model 6 or Model 8
System
.............................. 1
2 Memory Conservation through Disk
Management
.......................... 10
3 Example of the Menus for Initialization
of a Disk Volume ...................... 11
4 Custom Procedure Example. . . . . . . . . . . . . . . . 12
5 Disk-Volume Layout .................... 14
6 Files and Directory Structure
.............•. 15
7 Multiuser BASIC Components
.............. 23
8 Pascal Programming Cycle ............•.... 30
9 Pascal Block Structure ................... 31
10 Typical Application of 3780 Emulator in
Distributed-Processing Environment
.......... 32
t 1 DS990 Standard and Optional Hardware . . . . . . •38
12 Workspace Pointer and Registers ............ 39
13 990 CPU rr I LIN E Address Space with
Map Option ................•......... 40
14 Model DS31 Disk System ................ .44
-15 -1)531 CbhfrolJerwfth-Follrtflsidlrives": .:~-. . . . .4-5
16 Model OSlO Disk System ...........•.... .45
17 Model DS25/DS50 Disk System ............. 46
18 Model 979A Magnetic-Tape Transport ......... 47
19 Model 911 Video Display Terminal. .......... 48
20 Basic VDT Kit ....................•... 48
21 Model 911 Keyboard ..................•. 49
22 Model 810 Printer ...................... 50
23 Model 2230 and Model 2260 Line Printers ...... 51
24 Model 733 ASR Data Terminal ............. 52
25 Model 743 KSR Data Terminal ............. 52
26 Model 804 Card Reader . ... . . . . . . . . . . . . . . .52
27 Model FD800 Floppy-Disk System
........... 53
28 990 Communications Modules .............. 53
29 Model 990/10 Minicomputer
............... 55
30 Model 990/10 Minicomputer Thirteen-Slot
Chassis ............................. 56
31 Standard 990 Chassis Configuration Chart ...... 56
32 Standard
Chassis Layout .................. 77
33 DS990 Enclosures ...................... 78
34 Dimensional Outline
of Model DS10 Disk on
"Quietized" Pedestal .................... 79
35 Dimensional Outline of DS25 or DS50 Disk on
Pedestal ............................. 79
36 Cabinet-Layout Worksheet ................ 80
37 Minimum Equipment Spacing for
DS990 Systems ........................ 84
38 DS990 Desk-System Packing Crate
........... 85
39 Exploded View of Single-Bay-Desk
Packing Crate
......................... 86
40 Exploded View of Double-Bay-Desk
Packing Crate
......................... 87
41 Typical Rack-Mounted-Disk-Drive Shipping
Configuration
......................... 88
42 Typical Pedestal-Mounted-Disk-Drive Shipping
Configuration
......................... 89
List of Tables
Th~ ~e
1 Areas Served by DX10 SCI Commands ........ 12
2 Device
and File Operations Available through 1/0
Supervisor Calls. . . . . . . . . . . . . . . . . . . . . . . . 16
3 Relative Power of COBOL. ................ 17
4 RPG II Enhancements ................... 21
5 BASIC and Business BASIC Statements ........ 24
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
BASIC Matrix Statements ................. 24
BASIC and Business BASIC Intrinsic
Functions
........................... 25
Conditional Relations for BASIC ............ 25
Operating Commands for BASIC
............ 26
Types
.............................. 28
Hardware Configuration for DX10
3780 Emulator
........................ 34
Hardware Configuration
for TX990
3780 Emulator
........................ 35
Maintenance-Agreement
Service ............. 60
On-Call Service
......................•. 60
SCI Command Index ......•.....•....... 65
990 Instruction Set ..................... 67
DX10 Memory-Estimating Form
............ 68
Recommended Software-Development
Configurations
........................ 70
Recommended Application-System
Configurations
........................ 71
Disk-Pack Sizes ........................ 71
DX10 So~~~e~i~Els.~.~. ~."~ .. ' .. ' ..... , .......•• L ••• 11
Software-Development Disk Requirements ...... 72
Chassis Planning Form ................... 73
Blank 990-Chassis Layout Form ............. 75
Blank CRUrrlLlNE Expansion-ChassiS
Layout Form ......................... 76
Basic DS990 System Kit Configurations ........ 82
DS990 Model 4 System Consolidated
Parts List. . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
DS990 Model 6 and Model 8 Systems
Consolidated Parts List ................... 90
DS990 Model 4 Commercial Consolidated
Parts List .•.......................... 90
DS990 Model 6
and Model 8 Commercial
System Consolidated
Parts List ............. 90
DS990
Basic Software-Package Contents for
HardwarelSoftware Versions ............•.. 91
DS990 Basic Software-Package Contents for
Hardware-Only Versions .................. 92
Optional DS990 Software, Object Format
...... 92
DS990 Hardware Options
...............•. 93
Standard DS990 Equipment Specifications
..... 94
Hardware Manuals .....................• 99
Software
Manuals ..................... 100

DS990 Commercial Systems Overview
The Model 4, Model 6, and Model 8 Systems,
shown in figure
1, combine the performance of the
Model 990/10 Minicomputer with the power
of the
DXI0 disk-based commercial operating system. The
systems are specifically designed for commercial,
interactive, multiuser, multitasking, multilanguage,
and communications applications.
The models differ in disk-file capacity to provide
an orderly growth path. The Model 4 System is a
10M-byte disk-based system suitable for a small
software-development system or medium-scale
application system. The Model 6 System
is a dual
25M-byte disk-based system suitable for medium-
scale software-development and application systems.
The Model 8 System
is a dual SOM-byte disk-based
system intended for medium- to large-scale software-
development and application systems. Physical
packaging differences between the three models are
based on the space requirements of the disk-storage
units.
The base systems are offered in the minimum
configurations that support the full functions
of the
operating system. This allows maximum flexibility in
adding optional software and hardware features to
customize a system. The various models are available
in either equipment-only versions or in versions that
include system software and installation. Software-
included versions provide a licensed copy of the
DX
10 operating system and software-development
facilities, documentation, and a one-year software
SUbscription service for the DXI0 system. A factory-
provided sysgen
is also installed on systems that
include software. Systems are configured and tested
before they are shipped from the factory.
1
Figure 1. OS990 Model 4 System (foreground) and Model 6
or Model 8 System (background)

DS990 Software
DS990 software is both versatile and efficient. It
comprehends user requirements in a way not found
in most computers
of this class.
DXIO Operating System
Operators interface with the DXIO operating system
through Model
911 Video Display Terminals (VDTs)
that provide hierarchical menus with supporting fill-
in-the-blank, prompting, and predefined functions.
More than
170 Texas Instruments-supplied system
commands provide powerful and comprehensive
system control. Users can also provide custom
commands that reflect their application terminology.
A broad range
of utilities and supporting routines
are built into the system-command structure.
Program memory
is dynamically allocated.
Resource management
is enhanced by variable-
location roll in/roll out and task-level priority
assignment.
The DXIO operating system has flexible
file
management. Types of files supported include
sequentiai, reiative-record, and muitikey-indexed
files.
The key-indexed method supports a unique real-time,
self-maintenance capability.
Program and Memory Management. The
DXIO operating system is a mUltiprogramming
system. User programs that operate under control of
the OX10 system include a composite of tasks,
procedures, and overlays. Programs are installed and
stored in program
files. When a program is
activated, its images are loaded into any available
memory area.
An active program can be rolled in and out of
several different locations in memory by the DXIO
operating system several times during its execution
to efficiently share memory and processor resources.
When in memory and active, a program competes
with other programs for execution time on a user-
defined priority basis. When a program terminates,
the operating system releases all program-owned
resources including files, devices, and memory. This
unique DXIO program structure
is made possible by
a memory-mapping technique. These advanced
memory- and program-management techniques
provide high processor utilization, resulting in high
levels
of throughput.
System Command Interpreter. Operators
interface with the
DXIO operating system through
VDTs via the system command interpreter (SCI).
The SCI
is a collection of more than 170 procedures
that provide system functions ranging from setting
2
the time of day or initiating compiles to backing up
disks. Commands are
at the operator's fingertips via
the SCI. This can save
10 to 30 percent of
development effort on major programs. The
completeness and flexibility
of the functions
performed by the SCI make it without parallel in
the minicomputer market. Many
of the functions
performed
by the SCI are found only on main-frame
machines.
Activation
of SCI commands is via a hierarchy of
command menus made available to all types of
system terminals. The command menus provide each
terminal on-line command prompts by logical
grouping.
Custom commands can be integrated into the
framework
of the DXIO operating system. Users can
combine SCI primitives with their own application
language to provide a user interface that
is unique
to the terminology and customary procedures of the
application.
Interactive Operation. The DXIO operating system
features an excellent interactive user interface for
control of the system through SCI.
All entries keyed
by an operator are ffieaningfuHy prompted. Fieids
are easily edited
by the operator and are verified by
the system. The number of prompts, and therefore
time, can be conserved since all arguments for a
command can be entered before the system requests
them by prompt. When a partial list
of arguments is
entered, any arguments not already supplied by the
operator or default specified are then prompted.
Batch Operation. The background program at the
terminal may
be a copy of the SCI. In this case, the
SCI
is interpreting commands in the background
(batch processing). Batch input
is from any
sequentially oriented
file device but not from the
terminal itself. An operator can initiate batch
processing, query its status, and receive information
concerning its normal or abnormal completion.
Certain interactive commands are inappropriate for
batch operation, but all other SCI commands are
available.
File Management
The DXIO operating system provides a file-
management package that includes a complete range
of file structures and features. The DXIO system can
accommodate many uniquely named data
files on a
disk cartridge and provides the necessary
management for allocation of disk space to the
files.
The user can specify the amount of space to be
allocated to a
file or, more frequently, can specify
that space
is to be automatically allocated to the file
as it is needed.

File Types. Three major file types are supported
by the DXI0 operating system: sequential, relative-
record, and multikey-indexed
files. Sequential files
allow records with concurrent reads. Relative-record
files provide rapid access to fixed-length records in
either random or sequential mode. In multikey-
indexed
files, variable-length records are accessed by
providing the DXI0 operating system
anyone of up
to fourteen
keys by which the data is known. The
keys are in sorted order and allow rapid access to
data addressed by the
keys.
rvtultikey indexing provides a unique self-
maintenance capability. Deleted or added keys are
automatically removed or inserted in the sorted
key
lists. The DX 10 system automatically expands or
contracts the
key lists and eliminates much of the
necessity for periodically rebuilding and reorganizing
files.
File Features. Various file features and file types
are available to the assembly-language user. High-
level languages mayor may not allow access to any
given feature, depending on the syntax of the
language. Some of the supported features include:
• Record locking
• Temporary files
• Blocked files
• Deferred or immediate write operation
• Delete and write protection
• Access privileges
• Blank compression and adjustment
• Expandable files
• Blank compression.
Error Control and System Log
The DXI0 operating system incorporates several
error-control features and supports an optional
system
log. The 990 mapping feature protects the
OX10 system from destruction by errant application
programs. An optional end-action routine analyzes
abnormal termination and takes appropriate recovery
steps.
High-Level Languages and Utilities
COBOL, RPG II, DBMS 990, BASIC, Business
BASIC, FORTRAN, Pascal, and Sort/Merge
packages are available as options on all DS990
systems.
The COBOL compiler conforms to the American
National Standards Institute (ANSI) COBOL subset
(ED lX3.23-1974) and incorporates extensions to this
subset to provide added capabilities.
The RPG II compiler conforms to the IBM
System/3* RPG II specifications with certain
equipment and teleprocessing exceptions. Texas
3
Instruments version of RPG II
is video-display-
oriented and provides one-line-at-a-time forms or
multiline listings.
Texas Instruments DBMS
990 is a modular data-
base management system specifically designed for
minicomputer applications. DBMS
990 includes a
data-definition language (DDL) for defining the
logical structure of data and a data-manipulation
language (DML) that interfaces through COBOL for
storing and retrieving data. A number
of utilities
and security features can optionally be used within
the modular structure of DBMS
990.
The BASIC** language is a version of Dartmouth
BASIC as described in BASIC Programming, by
Kemmeny and Kurtz, with certain extensions to
enhance its
use. The extensions are integer arithmetic
type, expanded string handling, CALL, and
subprograms.
BASIC is aimed at the scientific user. Business
BASIC, a variation of BASIC, is an easily
understood, business-oriented, application-solving
language. Single-key-indexed
file input/output (I/O)
and limited-output editing capabilities are included to
provide a check-printing capability.
The FORTRAN compiler conforms to the ANSI
standard FORTRAN, or FORTRAN IV. The
compiler also incorporates the extensions
recommended by the Instrument Society of America
(lSA-S61.1, 1975 and ISA-61.2, 1976).
Pascal is a general-purpose language well suited
for a variety
of applications. Originally designed as a
language for teaching a systematic concept
of
programming, Pascal is straightforward to learn and
to
use. Its readability makes the language especially
useful when programs must be maintained
by users
other than the original author.
The DXI0 operating system supports a
comprehensive Sort/Merge package that can
be
accessed in several ways. SCI provides commands to
access Sort/Merge in batch or interactive mode.
COBOL, RPG II, FORTRAN, and BASIC
programs can interface with Sort/Merge by using the
CALL statement. Both sort and merge processes
support record selection, reformatting on input, and
summarizing on output. Ascending key order,
descending
key order, or an alternate collating
sequence can be specified.
Program-Development Tools
In addition to a comprehensive set of utilities that
operate in conjunction with the DXI0 operating
*IBM System!3 is a registered trademark of IBM.
**BASIC is a registered trademark of Dartmouth College.

system, Texas Instruments provides four major
program-development tools: interactive text editor,
macro assembler, link editor, and debug package.
Each
of these operates under SCI and is easily
invoked by
operator commands.
Communications Software
The OXI0 3780 Emulator provides the OS99O family
of commercial systems with a means of remote-job-
entry
(RJE) communications with an IBM 360/370
host computer or another 3780 emulator-equipped
990 computer.
Operation of the IBM 3780 Oata
Communications Terminal is emulated. OS990
systems so equipped can operate in unattended mode
as central
or satellite stations in a distributed
network. Optional auto-call capability is also
provided.
Oata files are transmitted over leased
point-to-point
or switched telephone lines at speeds
up to 9600 baud. Any file or system device can be
specified
to transmit or receive data. Hardware
support of 3780 emulation is provided with the 990
communications interface module to a customer-
supplied modem
or Texas-Instruments-supplied
modem kit
and optional auto-call unit.
DS990 Hardware
The DS990 disk-based systems require a fast, flexible
computer architecture to meet the processing
demands of multiple interactive operations. The
Model 4, Model 6, and Model 8 Systems are based
on a minimum 128K-byte 990 processor with 16K
random-access-memory
(RAM) technology. The
processor features the TILINE· asynchronous, high-
speed
data bus and a memory-mapping technique
that allows addressing of up to 2048K bytes of main
memory.
AU-models employ moving...Jtead- disk drives with
at least one removable disk pack and one additional
fixed
or removable disk pack. This allows copy,
backup,
and transportability of media that are so
important in interactive systems.
Each system includes one 1920-character video
display terminal
and keyboard. A dual-terminal
controller
is included and allows the easy addition of
a second VDT. Additional VDTs are available as
options.
990 Processor
The 128K-byte 990 processor features an advanced
memory-to-memory architecture
and TILINE
asynchronous, high-speed data bus. Current models
offer main-memory capacities up
to 384K bytes of
metal-oxide-semiconductor (MOS), 16K dynamic-
*TILINE is a registered trademark of Texas Instruments.
4
RAM, error-checking-and-correcting (ECC) memory.
The additional
ECC memory is available in various
module sizes.
TILINE expansion to a second chassis
is recommended for these memory modules. Memory
can be further expanded by adding standard 990
options.
The 990 processor includes a dual input/ output
system, a high-speed, asynchronous parallel TILINE
bus, and a low- to medium-speed command-driven
communications register unit
(CR U).
TILINE Peripherals
TILINE peripherals are high-speed I/O systems
which transfer
data to and from 990 memory at
rates that approach the instruction execution rate of
the 990 computer.
The DS990 base system includes one
of the
following disk systems, depending
on the model
selected. The DS31 Disk System has a 2315-type disk
cartridge with 2.8M bytes
of formatted capacity.
This disk drive
is an option on the Model 6 and
Model 8 Systems.
The OSlO Oisk System has a single-spindle, fixed-
and femovabie-piaUer disk drive employing the 5440-
type disk cartridge. Each platter has a 4.7M-byte
capacity
for a combined disk-drive capacity of 9.4M
bytes. This
is the disk drive supplied with the Model
4 System
and is offered as an option on the Model
6
and Model 8 Systems. One DS I0 disk controller
can accommodate up to two DS I0 disk drives.
The DS25 Disk System has a multiplatter disk
pack with 22.3M bytes
of formatted capacity. Dual
DS25 disk drives are employed on the Model 6
System. One OS25 disk controller can accommodate
up to four DS25 disk drives.
The
.DS50 .. Disk.System .. has.amllltiplatter· disk
pack with 44.6M bytes of formatted capacity. Dual
OS50 disk drives are employed on the Model 8
System. One OS50 disk controller can accommodate
up to four DS50 disk drives.
The Model 979A Magnetic-Tape Transport is an
optional TILINE peripheral. Two versions are
available:
an 8OO-bits-per-inch, nonreturn-to-zero
format
and a 1600-bits-per-inch, phase-encoded
format. Both versions use industry-compatible, nine-
track
tape formats. The transport operates at 953
millimetres
per second (37.5 inches per second).
CRU Peripherals
The command-driven communications-register-unit
(CRU) peripherals are low- to medium-speed I/O
systems that transfer data to and/ or from the 990
processor. These peripherals are optional features
that further enhance the DS990 system.

The Model 810 Printer is an impact printer with
9 x 7 dot-matrix character structure and a ninety-
six-character, full ASCII, compressed print set. The
810 printer prints 132-column lines at 150 characters
per second with eight-channel vertical-format control.
The Model
2230 and Model 2260 Line Printers
print 136-column
lines at 300 lines per minute and
600 lines per minute, respectively, with vertical-
format control, internal self-test, static eliminator,
and standard ASCII, sixty-four-character set.
Additional Model
911 Video Display Terminals
are available
as single- or duai-terminal displays with
keyboards and interfaces. A maximum of
twelve
VDTs can be installed in their predefined slots in a
two-chassis configuration. Additional VDTs can
be
installed in other vacant slots by redefining the
interrupt assignments. VDTs can also
be installed in
add-on chassis.
The Model
804 Card Reader is a 400-card-per-
minute reader that takes standard-sized, eighty-
column punched or marked cards.
The Silent 700· Model
733 ASR and Model 743
KSR Data Terminals use Texas Instruments unique
solid-state, thermal printheads for virtually silent
printing of eighty-column lines at thirty characters
per second. A typewriter-style, limited ASCII
keyboard allows operator entries.
The Model FD800 Floppy-Disk System provides
transportable diskette media to smaller members of
the
990 family of systems.
·Silent 700 is a registered trademark of Texas Instruments.
s
Communications Equipment
and Special Interface Devices
Optional communications equipment includes an RS-
232-C communications interface module for
asynchronous and synchronous transmission at
selectable baud rates from
75 to 9600. Other
supporting options include asynchronous and
synchronous modems and auto-call. A variety of
interface modules for custom-device interface or
process monitoring and control are available
including analog-to-digital converters and digital
input and output interfaces. A variety of
Teletypewriter/Electronics Industries Association
(TrY /EIA) interfaces are also available.
990 Chassis Considerations
The 990 computer is packaged in a thirteen-slot
chassis with a programmer panel. The chassis
includes a
4O-ampere power supply and a disk-loader
read-only memory (ROM). One or more chassis can
be added to the system to provide additional
mounting space or dc power.
Customer-Support Services
Texas Instruments customer services encompass the
following areas: hardware installation, software
installation, hardware maintenance, software update,
education classes, and telephone hot
line. Individual
services can
be selected to best suit application and
customer requirements.