Control Data Corporation SYSTEMS TERMINAL II Owner's manual

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CDC® INFORMATION
SYSTEMS TERMINAL II
HARDWARE MAINTENANCE MANUAL
(SITE AND SUPPORT INFORMATION)
82100083

CAUTION
BEFORE READING THIS MANUAL, REVIEW
FEDERAL COMMUNICATIONS COMMISSION
REGULATIONS FOUND IN APPENDIX A.
ALSO, ONLY TRAINED CDC PERSONNEL
ARE AUTHORIZED TO MAKE REPAIRS TO
THIS TERMINAL.

REVISION
A
(09-10-79)
B
(09-27-79)
c
(10-03-79)
D
(10-10-79)
Publication No.
82100083
REVISION RECORD
DESCRIPTION
Final release; includes ECOs 13578, 13614, 13632,
and 13656.
Manual revised to reflect technical corrections.
Manual revised to reflect technical and editorial
changes.
Manual revised to reflect changes and additions to
text and incorporate ECO's 13627, 13646, 13672,
13675, 13700 and 13718.
01989-2
Address comments concern ing this
manual to:
REVISION LETTERS I, 0, Q AND X ARE NOT USED
Control Data Corporation
Technical Publications Deportment
2401 North Fairview Avenue
(C) 1979
by C:ontrol Data Corporation
Printed in the United States of America
St. Paul, Minnesota 55113
or use Comment Sheet in the bock
of this manual.
iii/iv

MANUAL TO EQUIPMENT LEVEL CORRELATION
This manual reflects the equipment configurations listed below.
EXPLANATION: Locate the equipment type and series number, as shown on the equipment FCO log, in the list below.
Immediately to the right of the series number is on FCO number. If that number and all of the numbers underneath it match
all of the numbers on the equipment FCO log, then this manual accurately reflects the equipment.
EQUIPMENT TYPE
SERIES
WITH FCO'S COMMENTS
FC816-A
01
FC816-B 01
XA243-A
01
01987-2
82100083
v

MANUAL TO EQUIPMENT LEVEL CORRELATION (CONTO)
EQUIPMENT TYPE
SERIES
WITH FCO'S
COMMENTS
XA244-A
01
XA247-A
01
01987-3
vi
82100083

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 poginoti~n rather than content has changed.
PAGE
REV
PAGE
REV
PAGE REV
Cover
-
4-1
A 6-41
D
Caution
-
4-2, 4-3
B 6-42
C
Title
Page
-
4-4
thru 4-8 A
6-43 thru 6-46
D
iii/iv
D
4-9 B
6-47 thru 6-56 A
v, vi
A 4-10
A
6-57
D
vii/viii
C
4-11
B 6-58 thru 6-61 A
ix/x
A
4-12
D 7-1 A
xi
A 4-13
B
7-2,
7-3 B
xii
D
4-14 thru 4-1S A
7-4
A
xiii
thru xvi
A
4-20 B 7-5
B
xvii
D
4-21
thru 4-2~ A 7-6, 7-7
A
xviii
A
4-25 B
7-8 thru 7-19 B
xix
D
4-26
A 7-20 thru 7-23
A
xx A
4-27, 4-28 B 7-24 thru 7-31
D
1-1
A
4-29
A 7-32 thru 7-49
A
1-2, 1-3
B
4-30, 4-31
B 7-50,
7-51
D
1-4
A
4-32
thru 4-4~
A 7-52,
7-53
A
1-5
B
4-45, 4-46
B
8-1
A
1-6
C
4-47
A
A-l,
A-2
D
1-7, 1-8
B
4-48
thru 4-5C B Comment
Sheet
D
1-9
D
4-51
D Mailer
-
2-1, 2-2
A
4-52
B Back Cover
-
2-3
thru
2-6
D
4-53, 4-54
A
2-7, 2-8
A
5-1 thru
5-57
A
2-9
C
6-1, 6-2
A
2-10
D
6-3
D
2-11
thru 2-13
A
6-4
thru
6-6
A
'2-14
B
6-7 B
2-15
C
6-8, 6-9
D
2-16, 2-17
A
6-10
thru 6-1·
A
3-1
D
6-18
C
3-2
A
6-19 B
3-3
D
6-20
A
3-4
thru 3-6
C
6-21
C
3-7
A
6-22
thru 6-3f A
3-8
thru 3-16
D
6-39
B
6-40 C
82100083 D
vii/viii

PREFACE
The CDC@ Information Systems Terminal II Hardware Mainte-
nance Manual contains site and support information. Sec-
tions contained in this manual are:
• General Description
• Operation
• Installation and Checkout
• Theory of Operation
• Diagrams
• Maintenance
• Parts Data
• Wire Lists
Appendix A contains the Federal Communications Commission
Regulations.
Additional reference and hardware maintenance information
applicable to the terminal is provided in the following
pUblications.
Title
Publication Number
PLATO Terminal User's Guide
+5-Volt Regulator Hardware Maintenance
Manual
Processor Module Hardware Maintenance
Manual
Key to Logic Symbology for Terminal
Equipment Manual
97404800
62960700
62960000
82172400
This manual and the previously listed manuals may be
ordered from:
82100083
Control Data Corporation
Literature and Distribution Services
304 North Dale Street
St. Paul, Minnesota 55103
ix/x

CONTENTS
1. GENERAL DESCRIPTION
Terminal Configuration • • . . . .. ...
Display • • • • • • • • • • • .
Operator's Panel ••••••••••••
Touchpanel . • . • • • . . • . .
Keyboard • •.•.•••••• •••
Enclosure . . . . .. ...
Controller ..•.••.•• .•...
Controller Board ..••.••.•••.
Video Board . . • . . . . .
Internal Modem . .• ••••••...•.
Power Supply . •. ....••• .. .
Communication Line Interfaces ...... .
Serial Channel Interface. . •..•
PLATO Communication Interface . . • . . . .
Parallel Channel Interface .••••.•..
Terminal Characteristics .•.•••.....
Physical Characteristics. . •.
Electrical Characteristics .....•.
Environmental Characteristics .••....
Performance Characteristics ••••
I/O Signal Cables . . .• ...•.
Grounding .• .. ..••.
2. OPERATION
External Controls, Indicators, and Connectors .
82100083
External Controls • • . • • . • • • . . • .
Alphanumeric Keyboard ••..•.••..
Power ON/OFF Switch •••..
Brightness Control . •• . •..
RESET Switch •...••..••
DATA/TALK Switch . • • . . •• . ..
Parameter/Mode Switches . . .....
SOFT/LOOD ••• • •• ••.•.•
LOOP/EXIT . . • • •• .•..•.
KB-TP/SKIP ••••.•• •.•
TEST/SKIP • • • . • •
External Indicators • .. .•.•.
DTR . •••. •••••.
DSR • • • • • • • • • • • • •
RTS • . • • • • • • • . • • • • • • . • •
Rev . . .. '.............
XMT • • •• •••
ERR •• •••••••••••••
External Connectors . • • • . • .
PLATO Communication Connector .
1-1
1-2
1-2
1-2
1-2
1-2
1-3
1-3
1-4
1-5
1-5
1-6
1-6
1-7
1-9
1-9
1-9
1-9
1-10
1-10
1-11
1-11
2-1
2-1
2-1
2-1
2-2
2-3
2-4
2-4
2-4
2-5
2-5
2-5
2-5
2-6
2-6
2-6
2-6
2-6
2-6
2-7
2-7
xi

,
Parallel Channel Connector . • . • •••
Serial Channel Connector •••••.
Composite Video Connector ••.•.•.•
Telephone Connec tor s . •. .••
Internal Controls, and Indicators • • •••
Internal Controls . • • • • • • • • • • • .
External Communications Loopback Switch .
Refresh Memory Write Switch • • • • • • •
Flood Screen Switch •••••••••••
Configuration/Mode Selection Switches
S2-l0 - Program Memory • • • • • • • •
S2-9 - Touchpanel • • • • • • • • • •
S2-8 - Serial Channel Stop Bits
Select • • • • • • • • • • • •
S2-7 - Forward/Reverse Channel • • • •
S2-6 - Serial Channel Parity Inhibit.
S2-3, S2-4, and S2-5 - Baud Rate
Selection • • • • • • • • • • • • •
S2-2 - RS-232-C/Long Line Selection
S2-l - Clear to Send . .• •••.
Video Controls Adjustments • • • • • . •
Power Supply Controls • •••••••
Internal Indicators •• ••••••
Video LED • • • • • • • • • • • • • •
Power Supply LEDs • • • • • • • • • • • •
2-8
2-10
2-10
2-11
2-11
2-11
2-11
2-12
2-13
2-13
2-13
2-14
2-14
2-14
2-14
2-15
2-16
2-16
2-16
2-16
2-16
2-16
2-17
3. INSTALLATION AND CHECKOUT
Crating • • . • . . • • • • • • • • • • • • 3-1
Uncrating • • • • • • •• .•••••• 3-1
Installation • • • • • • • • • 3-3
Checkout • • • • • • • • . . . • • • • • • •• 3-8
Memory Expansion Installation • • • . • • • 3-8
Installation Instructions for Optional Modem
(XA247-A) ••••••••••. 3-9
. Connecting Terminal to PLATO System • • • • •• 3-13
4. THEORY OF OPERATION
xii
Controller ................ I. •
Controller Board • • • •
Execution Times . ••••
PLATO Communications Interface . • .
PLATO Receiver • . • • • • . • • .
Word
Format . • • . • . • • • .
Word Polarity • . • • • • • .•
Word Parity. • . •• • ••••
Data Rate . • • . • . • • ••.
Data Assembly/Transfer
PLATO Transmitter
Word Format'. . . • . . ..•.
Word Polarity . . •.•
Word Parity . • • • ••
Data Rate . • . •• ••••
Data Transfer/Disassembly • • • • •
Signals . • • • • • • . • •
4-1
4-1
4-3
4-6
4-6
4-6
4-6
4-7
4-7
4-7
4-8
4-8
4-9
4-9
4-9
4-9
4-10
82100083 D

82100083
Long Line Receiver
Long Line Driver •••••••••
Serial Channel Interface •••••••.
Interface • • • • • • • • • .
Signals . . . . .. ...... .
Send • • • • •• •••••
Received Data, BB • • •• ..•
Request to Send (RTS), CA •••
Clear to Send (CTS), CB • •
Data Terminal Ready (DTR), CD .
Data Set Ready, CC ••••••
Carrier Detect ••••••..••
Data Format • • • • • • • • • . . • .
Timing . . . . . .. ...... .
Switches • . • • • • •• ••.
Clear to Send (CTS) • • • • • • • .
Parity Enable/Inhibit. • ••.
Program Instructions • •• ••••
Load Serial Data (Output 06) •••
Load Serial Control (Output 07)
Read Serial Data (Input 05) ••
Read Ser ial Status (Input 06) • • •
Parallel Channel Interface •••.•..
Signals . • • • . • • • • • • • •
Timing . . . . . . . . . . . .
Output Cycle • • • • •
Input Cycle • • • • • • • . • •
Terminal Identification ••....•
Programming • • • . • • • . • • •
Video Board • • •• ••••••••••
Memory Expansion • • . • • • • • • • . .
Programming • • • • . • • • •
Memory Structure • • • • . • •
Read-Only Memory • • • . • • .
Program RAM • • • ••• • • • •
Display Refresh Memory
I/O Peripheral Devices •••..•
Read Configuration Switches
(Input 00) • • • • • •
Load Maintenance Register
(Output 00) •••..•
Read Keyboard Data (Input 01) ••.
Load Transmitter Lower Bits
(Output 01) ••••••••••
Read Touchpanel Data (Input 02)
Load Transmitter Upper Bits
(Output 02) •••••.•••.
Read Lower ID (Input 03) ••••.
Bulk Write/Erase (Video Enable/
Disable, Output 03)
Read Upper ID (Input 04) •••
Load Interrupt Mask (Output 04)
Read Serial Data (Input 05) ••
Miscellaneous Control (Output 05) •
4-10
4-11
4-12
4-12
4-12
4-12
4-12
4-13
4-13
4-13
4-13
4-13
4-13
4-14
4-15
4-15
4-15
4-16
4-16
4-16
4-18
4-18
4-20
4-20
4-22
4-22
4-24
4-25
4-25
4-26
4-28
4-28
4-28
4-29
4-29
4-30
4-33
4-33
4-33
4-36
4-36
4-36
4-36
4-36
4-36
4-37
4-38
4-39
4-39
xiii

Read Serial Status (Input 06) •••
Load Serial Data (Output 06) •••
Read Controller Status (Input 07) •
Load Serial Control (Output 07) ••
Read Communication Line (Input 08).
Input Parallel Channel (Input 2Y,
3Y) ••••••••••••
Output Parallel Channel (Output 2X,
3 X) ••••••••••••••
Composite Video Interface ••••••
Communication Interface/Internal Modem •
Internal Modem • ••••••••••
Operators Panel • . • • • • • • • • • • • •
Touchpane1 ••• • • • • • • • • • • • • •
Power Supply • • • • •• •••••
Video Monitor • • • • • • •
Keyboard ••• • • •• ••••••
5. DIAGRAMS
Logic Diagram Set Contents Sheet • • • • • • •
Key to Diagrams Physical Location Codes • • • •
Key to Symbols • • . • . • • • . . • •
Cabling and Interconnection Diagram • • • • • •
Schematic Diagram, 8AGD Power Supply 1 • • • •
Schematic Diagram, 8AGD Power Supply 2
Video Controller (7BGD) External Connections
Schematic, Display Logic Cable • • • • • • • .
Display Schematic • • . • • • • • • • • • • • .
Controller Module (7BFD) External Connections •
Video Controller (7BGD) Block Diagram •
Controller Module (7BFD) Block Diagram
Oscillator, CPU Interface •••••••••••
Dot Timing Chain • • • • • . • • • • •
Vertical Timing • • • • • • • • • • • . • • • .
Horizontal Timing, Memory Window Timing
Memory Window Timing • • • • • • •
Video Shift RGTRS/MUX, Display Drive Logic
Bulk Write/Erase, Video Disable •....••.
Programmed EROM, Processor Memory Timing • • •
Display Address Register, Display Memory
Timing . . . . . . • .. ....
Display Memory Address MUX . • • •
Display Memory • • • • • • •
Processor Memory ••• • • • • . • • •
Memory Output Buffers • • • • • • • • •
Data Bus Transceiver, Composite Video.
Video Controller Module (7BGD); Power, Ground,
& Decoupling • • • . . . . . . . • . . . . .
Video Dot Timing, Character Timing and Memory
Wi ndows • • • • • • • • • • • • • • • • • •
Line Timing Field (50/60 Hz) Timing • • • •
Display Memory Timing • . • • • . • • • • • • •
4-40
4-41
4-41
4-42
4-42
4-43
4-43
4-43
4-45
4-48
4-49
4-49
4-50
4-51
4-52
5-2
5-4
5-5
5-6
5-7
5-8
5-9
5-10
5-11
5-12
5-13
5-14
5-15
5-16
5-17
5-18
5-19
5-20
5-21
5-22
5-23
5-24
5-25
5-26
5-27
5-28
5-29
5-30
5-31
5-32
xiv
82100083

Z80 Microprocessor, Reset Logic
uP Signal Buffers . • • • • • • . . . .
Inpu t MUX • • . • . . • • . • • • • • •
I/O Control • • • •• •••••••••••
I/O Control, Op Panel LED RGTR & DRVRS
Feature Select Switches, 1.0. Code Shunts.
Keyboard Scanner & Contact Detection Logic,
Interrupt Mask RGTR & Encoder •• • . •
PLATO XMT Shift Registers, Serial Baud Rate
Generation, Interval Timers . • • . • .
PLATO Communications Control • • . • • • •
Long Line Receiver, RS232 Drivers & Receivers.
PLATO Receiver Logic ..••••......•
Serial Baud Rate MUX, Touchpanel Contact
Detect . . . . . . . . . . . . . .
Serial Channel UART, Long Line Driver •••.•
Touchpanel Logic X-Scanner ••.••• . . . .
Touchpanel Logic Y-Scanner ••.•••••.•
Controller Module (7BFD); Power, Ground &
Decoupling • • • • • . • • • • . • .
Processor Memory Cycles • • • • •• • • . •
PLATO Receiver Timing • • • • • • • • •
PLATO Transmitter Timing ••• • •..
Operator's Panel (7BVD) • . . • •• . .••
Keyboard • • • • • . • • • • • • •• .••
Logic Diagram, Touch Panel (Optional) • . • • •
Modem Option, Transmitter & DAA • •• • ••
Modem Option, Receiver •..•. • • • . . . .
Modem
Option; Power, Ground, & Decoupling •
6. MAINTENANCE
Suggested Emergency Maintenance Procedure •
Before Leaving for Customer Site ••••••
Upon Arriving at Customer Site ••....•
Maintenance Aids • . • • • •. •••.••
Resident Diagnostics • • • •
RAM Memory Test • • • • • . • • •
Serial Interface Tests •..•••.
PLATO Serial Interface Test ••.
External Serial Interface Test ••••
CRT Alignment, Touchpanel, and Keyboard
Tests . . . . . . . . . . . . . .
Diagnostic Error Indication • • • • • • •
System Diagnostic Less (DIAG) •••••••
Preventive Maintenance • • • . •• .•••
Special Tools and Test Equipment . • •
MaS
Circuit Handling Precautions •.•...•
Diagnostic and Corrective Maintenance
82100083
Procedures • • • • • • • • . • • • . • . • •
Diagnostic Decision Logic Tables • • ••
Conditions Quadrant . . • • • • • • •
Situations Quadrant ••••.•...••
5-33
5-34
5-35
5-36
5-37
5-38
5-39
5-40
5-41
5-42
5-43
5-44
5-45
5-46
5-47
5-48
5-49
5-50
5-51
5-52
5-53
5-54
5-55
5-56
5-57
6-1
6-1
6-2
6-3
6-3
6-3
6-4
6-4
6-4
6-5
6-5
6-7
6-7
6-8
6-9
6-10
6-10
6-11
6-11
xv

7.
xvi
Sequence Quadrant • • • • • • • • • •
Actions Quadrant • • • • . • • • • •
Arrangement of Diagnostic and Corrective
Maintenance Information . • • • • • • • •
Procedure 1 - Turning On/Off Terminal.
Procedure 2 - Executing Resident
Diagnostics • • • • • • • • • • • •
PARTS
Spare
Spare
Spare
Spare
Error Indications • • • • • • • • • •
Procedure 3 - Executing System Diag-
nostic (DIAG) • • • • • • • • • • •
Procedure 4 - Removing Hood and Bezel.
Procedure 5 - Aligning and Adjusting
CRT • • • • • • • • • . . . . .
Procedure 6 - Adjustment of Yoke
Centering Rings ••••••••••
Procedure 7 - Replacing Video or Con-
troller Printed Circuit Boards
Procedure 8 - Replacing IC Chips • • .
Procedure 9 - Adjusting Power Supply •
Procedure 10 - Replacing Power Supply.
Procedure 11 - Replacing 60 Hz or
50 Hz AC Entry Panel, and 50 Hz
Transformer • • • • • • • •
Procedure 12 - Replacing Power ON/OFF
Switch/Circuit Breaker ••••••
Procedure 13 - Replacing Keyboard
Assembly and Components • • • • • •
Procedure 14 - Replacing Operator
Pane 1 • • • • • • • • • • • • •
Procedure 15 - Replacing Operator
Panel LEOs • • • • • • • • • •
Procedure 16 - Replacing BRIGHTNESS
Control • • • • • • • • • • • • • •
Procedure 17 - Replacing Access Door
Procedure 18 - Replacing CRT or Display
Board • . . . . • • • . . . . • • •
Procedure 19 - Replacing Voltage
Doubler/Bleeder Assembly • • •
Procedure 20 - Replacing Touchpanel
Procedure 21 - Replacing Internal
Modem • • • • • • • • • • • • • • •
Procedure 22 - Checking Video Offline.
Procedure 23 - Defining Acceptable
Display Quality ••••••••••
INDEX
DATA
Parts
List
1ST-II Basic
Terminal
. . . .
Parts
List Touch Panel Option
. .
Parts
List
Internal Modem Option
Parts List Memory Expansion Option
. . .
6-13
6-13
6-14
6-21
6-21
6-23
6-24
6-26
6-29
6-31
6-32
6-36
6-38
6-41
6-43
6-45
6-46
6-49
6-50
6-51
6-52
6-53
6-55
6-55
6-57
6-58
6-59
7-2
7-4
7-5
7-6
82100083

8.
Genealogy 1ST-II 50/60 Hz • • • • • • •
1ST-II Terminal 50 Hz TLA • • • . • • •
1ST-II Terminal 60 Hz TLA • • •• ••••.
AC Entry Assy . • • . • • • • • . • • . • •
AC Entry Assy 50 Hz 220 V • . . • . • .
P.C. Card Assembly, 8AGD (LCIST Power Supply) •
. P.C. Card Assembly, 7BFD (Control Module) •
Module W/Firmware • • • • • • • • • • • • •
P.C. Card Assembly, 7BVD (Operator's Panel)
P.C. Card Assembly, 7BGD (Video Controller)
IC Programmed EROM 1ST II • • • • • • • . • • •
Cable Assy-Over Voltage •• •••••.••
Cable Assy-Over Voltage (50 Hz) • •• • ..
Cable, Display Logic ......•
Cable Assy-Logic Signals . • . • . . . . .
Cable Assy-D C Power .•• • • • •
Cable Assy-Video Output • ••.•...•.
WIRE LISTS
. . . . . . . . . . . . . . . . . .
APPENDIX
7-7
7-8
7-14
7-20
7-22
7-24
7-28
7-32
7-34
7-36
7-40
7-42
7-44
7-46
7-48
7-50
7-52
8-1
A. FEDERAL COMMUNICATIONS COMMISSION REGULATIONS. A-l
FIGURES
1. GENERAL DESCRIPTION
1-1
Terminal
. · · · · · · · · · · · · ·
1-2
Serial
Word Format
· · · · · · ·
1-3
Long Line Receiver
· · · · · · · · · · ·
1-4
Long
Line Driver
· · · ·
2. OPERATION
2-1
2-2
2-3
2-4
2-5
External Controls and Indicators . . • .
Alphanumeric Keyboard ••••..
External Connectors • • • • • • • • . • •
Internal Controls . . . • • . . • . .
Configuration/Mode Selection Switch
Polarity •.•••••••••••
3. INSTALLATION AND CHECKOUT
3-1
Terminal Packaging
· · · · · · · · ·
3-2
Terminal/Telephone
Connection
· · · ·
3-3
Interface Cable Kit
· · · · · · ·
3-4
Video Board
IC
Locations for
Memory
Expansion
. · · · · · · · · · · ·
3-5
Optional Modem Installation
· · · · ·
3-6
Modem Shield and Printed
Circuit Board
Installation
· · · · · · · · · · · · .
82100083
D
1-1
1-6
1--7
1-8
2-2
2-3
2-7
2-12
2-13
3-2
3-3
3-7
3-9
3-11
3-12
xvii
I

4.
THEORY OF OPERATION
4-1
Block
Diagram
· · · · · · · · · · · ·
4-2
4-2
Controller Board Block Diagram
· · ·
4-4
4-3
Receiver Word
Format
· · · · · · · ·
4-6
4-4
Receiver Data Transfer
· · ·
4-8
4-5
Transmitter Word
Format
· • · · · · · · •
4-9
4-6
Transmit Data Transfer
· · ·
4-10
4-7 Long
Line
Receiver
• · · · · · • · · • ·
4-11
4-8
Long
Line Driver
· · · · · ·
4-11
4-9 Serial Word
Format
· · · · · · · · · · ·
4-14
4-10
Serial
Transmit
Timing
· · · · · • ·
4-14
4-11
Serial Receive Timing
· · · · · · · · · ·
4-15
4-12
Serial Channel Status
Word · · · · ·
4-18
4-13 External
Input
or
Output Timing
(No
Extra
Wait
Sta tes)
· · · ·
4-24
4-14 External
. Input
or Output
Timing
(Wi th
Extra
Wait States)
· · ·
4-25
4-15 External
Input or Output Timing
(Timeout
Condi tion)
· · · · · · · · ·
4-26
4-16 Video
Board
Block
Diagram
· · · · · ·
4-27
4-17
Memory Assignment
· · · · · · · ·
4-29
4-18
Address
8409
16 · · · · · · · · · · ·
4-31
4-19
Controller Status Word Format
· · · ·
4-41
4-20 Scan
Line Timing
(50/60
Hz)
· · · · · · ·
4-44
4-21 Frame Timing
(50/60
Hz)
· · · · · · · · ·
4-44
4-22
Expansion
Module/PLATO
Interface
Signal
Routing
· · · · · · · · · · · · ·
4-47
4-23 Keyboard
Codes
and Legends
· · · · · · ·
4-52
6.
MAINTENANCE
6-1
RAM Chip
Locations
· · · · · · · · · · ·
6-6
6-2
Example
of a Diagnostic
Decision
Logic
Table
. · · · · · · · · · · · · · · ·
6-12
6-3
Arrangement
of Diagnostic and
Corrective
Maintenance
Information
· · ·
6-14
6-4 Keyboard
Codes and Legends
· · ·
6-22
6-5 RAM Chip Location
·
6-23
· · · · · · · · · ·
6-6
Welcome Page Display
· · · · · ·
6-25
6-7 Group
Name
Page Display
·
6-26
6-8 Hood Removal · · · · · · · · · · · · · ·
6-27
6-9 Bottom of
Terminal
· · ·
6-27
6-10 Bracket
Screws Removal · · · · · · ·
6-28
6-11
Display
PC
Board
· · · · · · · · · · · ·
6-30
6-12 CRT Centering Rings
· · · · · · · · · · ·
6-31
6-13
Video and
Controller Board Locations. 6-33
6-14
Board Retainer Clips
· · · ·
6-34
6-15 Video
Board
· · · · · · · · · · · · ·
6-34
6-16 Controller Board
· · · · · · · · · ·.
6-35
xviii
82100083

6-17 IC
Locations
on
Controller Board
· · · ·
6-37
6-18
IC
Locations 'on Video Board
· · · · · · ·
6-37
6-19
IC
Locations on
CRT Monitor
Display
Board 6-38
6-20
Power Supply Board
· · · · · · · · · · ·
6-39
6-21
Test Points for +5 V on Controller
Board 6-40
6-22
Test Points for
+55 V on Display
PC
Board 6-40
6-23
Power Supply Adjustments
· · · · · ·
6-41
6-24
CRT Chassis Removal
· · · · · · · · · · ·
6-42
6-25
Power Supply Removal
· · · · · ·
6-43
6-25.1 50
Hz Transformer
Removal
· · · · · ·
6-44.1/2
6-26
Power Switch Replacement
· · · ·
6-45
6-27
Space Bar Removal
. · · · · · · · · · · ·
6-46
6-28
Keyboard Assembly Removal
· · · · · ·
6-47
6-29
Keyswitch Replacement
· · · · · · · ·
6-49
6-30
Operator
Panel Removal
· · · · ·
6-50
6-31
Operator
Panel
· · · · ·
6-51
6-32
CRT Removal
. . . . · · · · · · · 6-53
6-33 Front Chassis
View
· · · · · · ·
6-54
6-34
Touchpanel
Removal
· · · · · · ·
6-56
6-35
'!'ouchpanel Alignment Marks
· · · · · · ·
6-57
•
TABLES
1. GENERAL DESCRIPTION
1-1 Device Inputs and Outputs . . • . • • . . 1-4
2. OPERATION
2-1 PLATO Communication Connector Pin
Assignments • . . . . . . • . . • . . 2-8
2-2
Parallel Channel Connector Pin
Assignments • • • . . .. .••• 2-9
2-3 Serial Channel Connector Pin
Assignments • . • . • • • . • • • . . 2-10
2-4 RS-232-C Interface Forward/Reverse
Channel Selection . . • . • . . • . . 2-15
2-5 PLATO Channel Baud Rate Switch
Selections . • • . • • • • • . •
3. INSTALLATION AND CHECKOUT
3-1
3-2
82100083 D
PLATO Interface Selections ...
Baud Rate Switch Selections . . ..
· 2-15
· • 3-6
• 3-7
xix
I

4. THEORY OF OPERATION
6.
7.
4-1
4-2
4-3
4-4
4-5
4-6
4-7
4-8
4-9
4-10
4-11
Device Inputs and Outputs ••••••
Serial Channel I/O Instructions •••
Serial Channel Word Length Selection
Serial Channel Baud Rate Selection •••
Input and Output Functions • • • • • • •
Bulk Write/Erase - Video Enable Function.
Interrupt Description ••••••••
Miscellaneous Control • • • • • • • • • •
I/O Expansion Module Pin Assignments
Touchpanel Connector AJ3 (Internal) •••
Keyboard Connector AJ2 (Internal) • •
MAINTENANCE
CRTl DOLT for Display Terminal
· . · · · · · ·
CRT2 DOLT for Display Terminal
· · · ·
CRT3 DOLT for Display Terminal
· · · · · ·
CRT4 DOLT for
Display Terminal
· . · · · · · ·
CRT5
DOLT
for Display
Terminal
· · · ·
PARTS DATA
7-1
Explanation of Column
Headings of Computer-
Generated Assembly
Parts
Lists
· · · ·
4-3
4-16
4-17
4-18
4-35
4-37
4-38
4-40
4-46
4-50
4-53
6-16
6-17
6-18
6-19
6-20
7-1
xx
6.
82100083