Control Data Corporation CDC 752 Manual

r.;J1::\ CONT"OL DATA
\::1 r::J CORfOR.i\TION
CDC® 752 KEYBOARD
DISPLAY TERMINAL
62957300
OPERATORS GUIDE/REFERENCE MANUAL
INSTALLATION INSTRUCTIONS

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Control Delta~~
Technicot PuWi~:-IJ~4I.WiM'
2401 Norfhf~--
St. Paul, Mi~-~
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Control
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Technical'PubJ:f.catt• ~fllent
2401 North Fairview A~
St. Paul, Minnesoto.5Jtla
Manual Title
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Publication No. · hvisfot:l
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01253

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REVISION
RECORD
REVISION
DESCRIPTION
01
Preliminary draft manual.
(12-08-76)
A
Manual released.
This printing obsoletes all previous editions.
(01-06-77)
B
Manual revised to include Installation
(08-02-77)
Rates.
Publication No.
62957300
REVISION LETTERS I, 0, 0 AND X ARE NOT USED
© 1977
by Control Data Corporation
Printed in the United States of America
Instruction and Impact Printer Print
01989-1
Address comments concern mg th 1s
manual to:
Control Data Corporation
Technical Publications Department
2401 North Fairview Avenue
St. Paul, Minnesota 55113
or use Comment Sheet in the back
of this manual.
v/vi

i
I (
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 SFC t
REV
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Cover
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Title Page
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Uodates
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2-21
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3-1 A
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02012-1
62957300 B
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LIST OF EFFECTIVE PAGES (CONTD)
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Comment Sheet
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viii
62957300 B

PREFACE
This manual contains operating and reference information for the CDC® 752 Key-
board Display Terminal. Basically this terminal
is a remote communications device
that operates in a conversational mode with a central processor at speeds of 110 to
9600 baud over a communication facility. As described within the following text,
the terminal is available in variant types to meet both national and international
standards and to provide for connection to different communications
facilities. Two
different character printers are also available for use as a peripheral on the terminal.
The main body of this manual contains information for reference by both systems
personnel and terminal
operators, and the appendix section contains terminal instal-
lation information for reference by technical personnel. Maintenance information
-for the terminal equipments is found in other CDC manuals.
To order additional copies of this manual, or copies of other manuals associated with
this terminal, please
contact:
62957300 A
Control Data Corporation
Technical Publications Department
2401 North Fairview Avenue
St. Paul, Minnesota 55113
ix/x

\
Section
2
l
62957300 A
CONTENTS
GENERAL DESCRIPTION
Functions • . • • • • . • • . • . • . • . . . . . • . • • • . • • • • • 1-2
Features • • • • . • . • • • • • . • . • • • • . • • • • • • . • • • 1-2
Display Unit Features • • . . • • . • • • . • • • . • • • • • • 1-3
Power Supply . . . . • . . . . . . . . . . . . . . . . . . . 1-3
CRT Monitor Assembly • • • • . • • • • • . . . • • • • • • 1-3
Control Logic PC Board • • • • • • • . • • • • • • • • • • 1-4
Keyboard Features • . • • • • • • • • • • • • . . • • • • • • • 1-4
Operator Contro I Features • • • • • • • • . • . • • • • • • 1-6
System/Terminal Interface Features • • • • • • • • . • . • 1-7
Non impact Printer Features • • . • . . • • • • • • • • • • • • 1-9
Print Mechanism • • • . • • . • • . • • • • • • • • • . • 1-11
Interface and Control Logic Cards • • • • . • • • . • • 1-11
Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
Impact Printer Features • • • . • • • • • • • . • • . . • • • • • 1-11
Print Mechanism . . . . . . . . . . . . . . . . . . . . . . . 1-13
Interface and Control Logic Cards ••••.•••••• 1-13
Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . 1-13
Features Summary List • • • . • • • . • • . • . • • • • • • • • 1-14
Equipment Specifications • • • • • • • • . • • • • . • • • • • • • 1-15
Environmental Specifications • • • • • • • • • • • • • • . • • 1-16
Keyboard Display Electrical Specifications • • . • • • • • 1-16
Nonimpact Printer Electrical Specifications • • • • • • • 1-16
Impact Printer Electrical Specifications • • • • • . . • • • 1-17
Keyboard Display Physical Specifications • • • • • • • • • 1-17
Nonimpact Printer Physical Specifications • • • • • • • • 1-17
Impact Printer Physical Specifications • • • • • • • • • • • 1-17
OPERATION
Keyboard Display Controls and Indicators ••.••...•.•
InternaI Contro Is • • • • • • • • • • • • • • • • • • • • • • • •
BAUD RATE Switches •••.•.•.•..•••.•••..
AUTO L1 NE FEED Switch •••••.•••••.•.•.•
MARK PARITY Switch •..••.••.••.•.•.•••.
50 Hz Switch .............•...........
SWITCH ED RTS Switch •••••••.••.•••..•••
CONSTANT DTR Switch ••••••.•.•...•••.•
INTERNAL TEST Switch
.................
2-1
2-1
2-3
2-3
2-3
2-3
2-3
2-4
2-4
xi

Section
Xi i
X/Y POSITION Switch
CURRENT LOOP Switch
Interface Jumpers •••......•.••.••..••..•
ExternaI Controls •.••••••••.•••••••••••••
INTENSITY Control ••••••••••••••••.••••
CO lnd icator .•...•..•......•.•....•..
ODD PAR/NO/EVEN PAR Switch ••••••••••••
FULL DUP/HALF DUP Switch ••••••••••.••••
0 N Ll N E/LOCAL Switch •••••••••••••••••
HIGH RATE/300/LOW RATE Switch •••••••••••
96/64 Switch ........................ .
PAGE Switch ........................ .
CB 1 Switch ......••...•....•........•
TEST/NORMAL Switch ••••••••••••••••••
Keyboard Data Entry and CentroI Keys ••••••••••
CLEAR Key •..•.•.•.•..•••••...•.....
BREAK Key .•..•.•.•.•.••..•••....•.•
ESC Key •.•...............•...••.•.•
SHIFT LOCK Key •••••••••••••.•.•.•••••
SHIFT Keys • • . . . . • • • . . • • . • • . • • . . ..••.
CONTROL Key •.......................
CONTROL Plus Keys ••••••••••••••••••
Fixed Code Keys •••••.••.••..••.•...•
Cursor Movement Keys ••••.••••••••••••
Special CONTROL Key Functions •••••••••
Line Clear ........•........•....
Initiate Low Intensity •••••.•••••••••
End Highlight •••••••••••••.•.•••••
Initiate Blink •••.•.•••••••.•.•••••
ETX Key ••....•.•...•.....••..•••••
RUB OUT Key •......•.........•......
CARRIAGE RETURN Key ••••••••••••.•••••
Cursor Positioning ( t,-, and-) Keys •••••••
Cursor Up (f) • • . • • • • • • • • • • • • . • • • . • . •
Backspace ( 4-- ) • • • • • • • • • • • • • • • • • • • • •
Skip ( --..) ..•.............•....••..
RESET Key ........•....•....•.•.••••.
LINE FEED Key •••••••.••.••••••.•••.•
REPEAT Key •••..•....•....••••••.•...
ENTER- Key ...•...•...••.••.••...•.•
ENTER+ Key •..••.•...••..••.......•.
2-5
2-5
2-5
2-6
2-6
2-7
2-7
2-7
2-8
2-8
2-8
2-9
2-9
2-9
2-10
2-12
2-12
2-12
2-12
2-12
2-13
2-13
2-13
2-14
2-15
2-15
2-16
2-16
2-16
2-16
2-16
2-17
2-17
2-17
2-17
2-17
2-18
2-18
2-18
2-18
2-18
62957300 A

Section
62957300 A
Nonimpact Printer Controls and Indicators ••••••••••
On Switch Indicator ...•......••..........
LF Switch •••.•.••••••...••.•.••..•.•.•
CR Switch ••.•••.•••••.••••..•••••.•.••
Single-Double Space Switch ••••••••••••••.••
Impact Printer Controls and Indicators ••••••• o •••••
ON/OFF Switch Indicator •••••••••••••.••••
START/STOP Switch Indicator ••.•••••••••••••
FORM FEED Switch •••••••••• o ••••••• o ••••
Test Print Switch ....•.....••.•..•••.•...
Forms Positioning Knobs • o •••••••••••••••••
Forms Density Control ••••••••.•••••• o • o •••
Horizontal Forms Positioning ••• o •• 0 ••••• o o o •
Preparation for Operation • o ••• o o o •• o •••••••••
Display Terminal •••••.••..••.••.•••.•.••
Check Items ••...•.....•.•...•••..•.•
Specific Functions ......................
Nonimpact Printer •••••••••.••.••••.•• , .••
Check Items •.•••...•.•.•.•••.••....•
Specific Functions •••••••• o •••••• o •••••
Impact Printer ••••••••••••••••••.•••••••
Check Items ••••.••••..•.••••••.•••••
Specific Functions ••••.•••• 0 •••••••••••
Forms Installation and Alignment ••••••••••
Ribbon lnsta llation •••••••••••••.•••••
Format Tape Installation ••••••.••••••••
Operator Supplies •.••..•••.•••.••.••••••
Nonimpact Printer ••••••••••.••••••.••••
Impact Printer ••.••.••••••••.••.••••.•
Forms Recommendations • • • • • • • • • • . • •••••
Ribbon Recommendations ••••••••••••••
Format Tape • • • • • • • • • • • • . • . • • • • • • • •
Terminal Operation ..••••.•.•........•.•..•
General Operating Information •••••.•••••••••
ODD PAR/NO/EVEN PAR Switch •••••••.•.••
ON LINE/LOCAL Switch •••..••••••.••.••
FULL DUP/HALF DUP Switch ••••.••..•••••
HIGH RATE/300/LOW RATE Switch •••••••••••
96/64 Switch ...................... .
PAGE Switch
...................... .
2-19
2-19
2-19
2-20
2-20
2-20
2-21
2-21
2-21
2-21
2-21
2-22
2-22
2-22
2-23
2-23
2-24
2-24
2-24
2-25
2-26
2-27
2-28
2-28
2-29
2-31
2-31
2-31
2-32
2-32
2-32
2-33
2-33
2-33
2-33
2-33
2-34
2-34
2-34
2-35
xiii

Section Page
3
4
A
B
Section
xiv
Online Operation . . . . . . . . . . . . . . . . . . . . . . . 2-35
Establishing Communications • • • • • • • • • • . • • • • 2-35
Logging In to the System • • • • • . • • • • • • • • • • • 2-36
Sending Messages • • • • . • • • • • • • • • • • • • • • • • 2-36
Receiving Messages • • • • • • . • • • . . • • • • • • • • • 2-36
Logging Out of the System • • • • • • • • • • • • • • • • • 2-37
Offline or Local Operation • • • • • • • • • • • • • • • • • • 2-37
SUBSYSTEM COMMUNICATIONS
Transmit/Receive Baud Rates •••••••••••••.•••••
Half- and Full-Duplex Modes of Operation •••••••••
Transmit/Receive Word Sizes and Formats ••••••••••
Transmit/Receive Code Set •••.•.••••••••.•••••
Error Detect ion • • • • • • • • . • • • • • • . • • • • • • • • . • ••
Current Loop Communication Interface
.............
CODES AND CHARACTER SETS
APPENDIX
INSTALLATION INSTRUCTIONS
IMPACT
PRINTER PRINT RATES
FIGURES
Figure
GENERAL DESCRIPTION
1-1
1-2
1-3
1-4
1-5
1-6
1-7
1-8
1-9
1-10
1-11
Terminal Configurations
Display Unit Components
Keyboard Layout •••.••••.••••.••••••.
Terminal Rear Panel •••..••••••••••••••
Nonimpact Character Printer ••••••.••••••
Nonimpact Printer Components ••••.•••••••
Impact Character Printer •••.•.•••.•••••
Impact Character Printer Components •••••••
Keyboard Display Terminal Dimensions •.••••
Nonimpact Printer Dimensions ••••••••••••
Impact Printer Dimensions •••••••••••••••
3-1
3-2
3-2
3-4
3-7
3-7
4-1
A-1
B-1
1-2
1-3
1-5
1-6
1-10
1-10
1-12
1-12
1-18
1-19
1-19
62957300 B

Section
2
3
4
62957300 A
Figure
OPERATION
2-1
2-2
2-3
2-4
2-5
2-6
2-7
2-8
2-9
2-10
2-11
2-12
2-13
Cabinet Hood RemovaI ••••••••••••••••
Internal Switches and Jumpers •••••••••••
External Controls, Keyboard and Front Panel ••
External Controls, Terminal Rear Panel ••••••
Keyboard Key Layout •••••••••••••••••
Nonimpact Printer Controls and Indicators ••••
Impact Printer Controls and Indicators ••••••
Terminal with Printer Option ••••••••••••
Removing the Detachable Keyboard ••••••••
Loading Paper in Nonimpact Printer ••••••••
Spoo I Loading ••••.••.•••••••••••••
Ribbon Loading • • • • • • • • • • • • • ••••..••
Front Tape Installation ................
SUBSYSTEM COMMUNICATIONS
2-2
2-2
2-6
2-9
2-11
2-19
2-20
2-22
2-23
2-26
2-29
2-30
2-31
3-1 Word Transmit Sequence • • • • • • • • • • • • • • •
3-3
3-2 Terminal Code Set • • • • • • • • • . • • • • • • • • 3-5
3-3 Data Set Connector Pin Assignments for Unipolar,
Full-Duplex, Current Loop Communication
Channe I • • • • . . • • • • • • • • • . • • • • . • • • 3-8
3-4 Data Set Connector Pin Assignments for Unipolar,
Half-Duplex, Current Loop Communication
Channe I • • • • • • • • • • • • • . • • • • • . • • • • 3-8
CODES AND CHARACTER SETS
4-1 Alphanumeric Dot-Matrix Formations and
Octal Codes . . . . . . . . . . . . . . . . . . . . . 4-2
4-2 Control Code Dot-Matrix Formations and
0 etaI Codes . . . . . . . . . . . . . . . . . . . . . 4-5
4-3 Nonimpact Printer Character Repertoire • • • • • 4-7
4-4 Impact Printer Character Repertoire • • • • • • • 4-9
XV

Section
2
3
4
xvi
f:j.
TABLES
Table Page
GENERAL DESCRIPTION
1-1 Available Terminal Configurations • • • • • • • • • 1-1
1-2 Peripheral Connector Pin Assignments • • • • • • • 1-7
1-3 Voltage Level Channel Interface Connector
Pin Assignments . . . . . . . . . . . . . . . . . . . . 1-8
OPERATION
2-1 Impact Printer Forms Requirements • • • • • • • . • • 2-32
SUBSYSTEM COMMUNICATIONS
3-1 TerminaiControiCodes ••.••••.•••••••• 3-6
CODES AND CHARACTER SETS
4-1 Display Keyboard Alphanumeric Character Set 4-1
4-2 Nonimpact Printer Alphanumeric
Character Set . . . . . . . . . . . . . . . . . . . . . 4-6
62957300 A

l
(
GENERAL DESCRIPTION
1
This section describes the general functions, features, and equipment specifications
of the 752 Keyboard Display Terminal and of the two printers that may be associated
with the terminal. It includes descriptions of both the basic terminal and its available
variations.
The basic terminal is a 50- or 60-Hz terminal with an 80-key keyboard and a modem
interface. The user can select 60-Hz versions of the terminal with a current loop
interface for connection to a current loop communication facility, or he can select
50-Hz versions with a current loop interface and/or FTZ approved shielding.* The
features
in corpora ted in each type of 752 Keyboard Display Term inaI are indicated
with Xs in table 1-1.
TABLE 1-1. AVAILABLE TERMINAL CONFIGURATIONS
TERMINAL TYPE
60Hz 50 Hz CURRENT LOOP FTZ SHIELDING
752-10 X ---
752-11 X -X -
752-20 -X -X
752-21 -X X X
Undesignated -X --
Undesignated -X X -
Additionally, the terminal is available with either a nonimpact thermal printer or
an impact printer. The keyboard display terminal and the two different printers
are shown in figure 1.., 1•
* FTZ (Fernmelde T echn isches Zentralamt) is a German Iicensing agency that sets
limits on the radio frequency emissions generated by electrical and electronic
devices. Many European countries have adopted FTZ requirements for the shield-
ing of electronic equipment in order to control the level of stray radio frequencies
in the atmosphere.
62957300 A 1-1

02201
FUNCTIONS
IMPACT
PRINTER
NOTE: BROKEN LINES SHOW INTER-
CONNECTING CABLE PATHS.
Figure 1-1. Terminal Configurations
The keyboard display terminal functions as a
stand-alone, remote input/output
device for a computer system. It performs input and terminal-control functions
via a detachable keyboard assembly, and it monitors both input and output functions
on a
12-inch crt display screen. Included within the terminal are all of the necessary
electronics, including an asynchronous, bit-serial, word-serial, communication
facility interface, to permit it to operate in conversational mode in the same manner
as a
teletypewriter unit. The display terminal, however, incorporates many features
not commonly found
in teletypewriter terminals; and the addition of one of the
available printer peripherals provides the terminal with hardcopy printout capabilities.
FEATURES
The following text highlights features of the terminal. These are described in the
following sequence: 1) display unit features, 2) keyboard features, 3) operator control
features, 4) system/terminal interface features, 5) nonimpact printer features, 6)
impact printer features, and 7) features summary list. Other portions of this manual
describe many of these features in greater detail; this portion of text provides
brief descriptions and a features summary to facilitate familiarization and comparison.
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62957300 A

DISPLAY .UNIT FEAITURES
The display unit of the terminal is a self-contained module that includes a power
supply, a crt monitor assembly, and a control-logic board. The keyboard,
communication I
ine, and printer unit interfaces are part of the logic PC board.
The location
of major components within the display unit is shown in figure 1-2.
Power Supply
CRT MONITOR
ASSEMBLY
CONTROL-LOGIC
RINTED CIRCUIT BOARD
Figure 1-2. Display Unit Components
The power supply furnishes
all necessary voltages for the display module from either
115 V ac or 220/240 V ac (nominal), 50- or 60-Hz power input sources.
CRT Monitor Assembly
The crt monitor assembly uses a 12-inch (diagonal measurement) crt, having a P4,
white-phosphor coating and a nonglare
faceplate. Nominal raster area on the dis-
play screen is an area approximately 7.8 in by 5 in (20 em by 12 em). This area
can display 24 Iines of up to 80 characters per Iine, with each character displayed
in a 7- by 9-dot matrix. Character display is accomplished by selectively blanking
62957300 A 1-3

and unblanking the dots within this matrix. A display-character refresh memory
holds
all the characters for display and refreshes the display screen at a rate equal
to the frequency
of the ac power input (50 or 60 Hz).
Control Logic PC Board
The display recognizes and generates 128 character codes; the 95 alphanumeric
character codes recommended by the American National Standards Institute (ANSI)
in standard X3.4-1968, and the 33 control codes recommended by ANSI in standard
X3.2-1973. During actual operation, the unit displays all 95 alphanumeric char-
acters and responds to 13 of the 33 controI codes as they are received. This leaves
20 control codes for use in specific functions or operations (refer to section 3 for
transmit/receive code
set). All 128 codes can be transmitted during normal online
operation
of the terminal.
Character entries onto the display screen occur upon code reception or
are made
via the keyboard module.
To assure entry at the desired screen location, a blinking
cursor underscores the location
of the next character entry. During consecutive
character entries, the cursor progresses across a display line through all 80 character
positions. At character position 73, a beeper signal sounds to warn the operator
that the end of a line is approaching. This line-by-line manner of cursor advance
continues until the last character position of the last Iine
is reached. As the last
character is keyed in, the cursor resets to its home position (upper left corner of
display area) or causes the display to scroll; that is, the cursor returns to the begin-
ning of the last line while all lines already entered scroll up one line (the first line
is lost as it scrolls off the screen).
Construction
of the display unit is modular as indicated in figure 1-2. All circuits
are solid-state, and with the exception of some of the power supply and high voltage
circuits, all use integrated circuit technology. Both the display unit and the key-
board enclosures are made of heavy-guage, molded, expanded-plastic, foam material
covered with a durable vinyl
paint. The overall design of the display unit lends
itself
to reliability, and the modular construction facilitates maintenance procedures.
KEYBOARD FEATURES
The keyboard of the terminal serves as both a terminal control and a data input unit
for the terminal
operator. The terminal control function of the keyboard is discussed
briefly
in the following portion of this section and more thoroughly in section 2 of
this manual. This portion of the text deals principally with the keyboard as a data
input unit. The keyboard uses a main key cluster of 67 keys, similar in appearance
to a standard teletypewriter keyboard, and a 13-key numeric-entry cluster, to
facilitate making numeric entries, located just to the right of the main key cluster.
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