Digital Equipment PDP-8/A Service manual

EK-SA001-0P-002
PDP-Sf A OPERATOR'S HANDBOOK
digital equipment corporation •maynard.massachusetts

PDP;;;8/A OPERATOR'S HANDBOOK
digital equipment corporation •maynard.massachusetts

18t Edition, September 1975
2nd Printing (Rev), September 1976
Copyright © 1975, 1976
by Digital Equipment Corporation
The material in this manual is for informational
purposes and
is subject to change without notice.
Digital Equipment Corporation assumes no respon-
sibility for any errors which may appear in this
manual.
Printed in U.S.A.
This document was set on DIGITAL's DECset-8000
computerized typesetting system.
The following are trademarks
of Digital Equipment
Corporation, Maynard, Massachusetts:
DEC
FLIP CIllP
DIGITAL
UNIBUS
DEC US
PDP
FOCAL
COMPUTER LAB
MASSBUS

CHAPTER 1
CHAPTER 2
2.1
2.2
2.2.1
2.2.2
CHAPTER 3
3.1
3.2
3.3
3.4
3.4.1
3.4.2
3.4.3
3.4.5
3.4.6
3.4.7
3.4.8
3.4.9
3.4.10
3.4.11
CHAPTER 4
4.1
4.2
CHAPTERS
5.1
5.2
5.3
5.4
CHAPTER 6
6.1
6.2
6.3
6.4
CHAPTER 7
7.1
CONTENTS
INTRODUCfION
PACKING AND UNPACKING INSTRUCTIONS
UNPACKING INSTRUCTIONS
PACKING INSTRUCTIONS
BA8-C Chassis Assembly .....
Other PDP-8/A Chassis Assemblies
SYSTEM DESCRIPTION
Page
2-1
2-1
2-1
2-3
GENERAL
....... . . . . . . . . . . . . . . . . . . . . .. 3-1
CHASSIS DESCRIPTIONS . . . . . . . . . . . . . . . . . . . . .. 3-4
EXPANSION TECHNIQUES . . . . . . . . . . . . . . . . . . . . .. 3-8
PDP-8/A MODULE DESCRIPTIONS ..................... 3-9
KK8-A Central Processor Unit (CPU)
.................. 3-9
MS8-A Read/Write Random Access Memory (RAM) .......... 3-11
MR8-A Read-Only Random Access Memory (ROM)
.......... 3-12
NHvI8-AA 8K Core Memory . . . . . . . . . . . . . . 3-15
MM8-AB 16K Core Memory . . . . . . . .
...... 3-16
DKC8-AA I/O Option Board
....... . .... 3-18
K~M8=A Extended Option Board .... ... . . . . . .... 3-22
Semiconductor Memory Power Supply . . . . . . . . . . 3-25
Core Memory Power Supply Regulator
........... 3-26
Limited Function Panel
................... . .... 3-29
KC8-AA Programmer's Console
........ . . . . . . . . . . . 3-30
INSTALLATION AND INITIAL POWER TURN-ON
ENVIRONMENTAL AND POWER REQUIREMENTS
INITIAL POWER TURN-ON ............ .
TESTING PDP-8/A WITHOUT PAPER TAPE DIAGNOSTICS
4-1
4-1
PROGRAMMER'S CONSOLE ........................ 5-1
CENTRAL PROCESSOR TEST ROUTINES ................. 5-1
ENTERING TEST ROUTINES FROM PROGRAMMER'S CONSOLE .... 5-1
CENTRAL PROCESSOR TEST ROUTINES . . . . . . . . . . . . .. 5-2
LOADING THE RIM AND BINARY LOADERS
LOADING RIM LOADER
.......... .
CHECKING THE RIM LOADER
....... .
LOADING THE BINARY LOADER ..... .
LOADING BINARY FORMATIEDPAPER TAPES
. . . . . . .. 6-1
6-2
6-2
6-3
TESTING THE PDP-8/A USING MAINDEC DIAGNOSTIC PROGRAMS
CENTRAL PROCESSOR UNIT (CPU) TEST
.. 7-1
iii

CHAPTER 8
S.l
S.2
S.3
S.4
CONTENTS (Cont)
ADDITIONAL DIAGNOSTIC TESTS
MEMORY TEST
......... .
DKCS-AA TEST . . . . . . . . . . .
KMS-A EXTENDED OPTION BOARD TEST
TESTING EXTENDED MEMORIES
CHAPTER 9 BASIC PDP-8/A MAINTENANCE
APPENDIX A INSTRUCTION SUMMARY
APPENDIX B DOCUMENTATION
APPENDIX C WARRANTY AND MAINTENANCE SERVICES
APPENDIX D
OMNmus LOADING
APPENDIX E POWER CONNECTION
Figure No.
2-1
2-2
2-3
3-1
3-2
3-3
3-4
3-5
3-6
3-7
3-S
3-9
3-10
3-11
3-12
3-13
3-14
3-15
3-16
3-17
3-1S
ILLUSTRATIONS
Title
SA420, SA620, SAS20 Packaging .
PDP-S/A Computer Packaging (Inner)
PDP-S/A Computer Packaging (Outer)
PDP-8/A Computer
........ .
Part of MS320 Module Showing R55, Which is Removed for SA Operation
PDP-8/A Semiconductor Chassis
.......... .
PDP-8/A Semiconductor Computer Chassis Dimensions
SA Chassis -H9300 (Transformer Cover Removed)
SA620 Chassis . . . . . . . . . . . . . .
SA420/SA620/SAS20 Chassis Dimensions
SA600/SA620 Expansion ....... .
KKS-A (MS315) CPU Module ..... .
MSS-A (MS311) Read/Write Random Access Memory
MRS-A (MS312) Read Only Memory (ROM)
MMS-AA SK Core Memory
.....
MMS-AB 16K Core Memory . . . . '. . . . .
DKC8-AA (MS316) I/O Option Board
D
Etch Revision of DKCS-AA (MS3l6) I/O Option Board
KMS-A (MS317) Extended Option Board .....
Semiconductor Memory Regulator Board (GS016)
SA Master/Slave Switch
............. .
iv
Page
S-l
S-2
S-6
S-9
Page
2-2
2-4
2-5
3-1
3-3
3-4
3-5
3-6
3-7
3-S
3-9
· 3-10
· 3-11
· 3-13
· 3-15
3-17
· 3-18
· 3-19
.. 3-20
3-25
· 3-27

Figure No.
3-19
3-20
3-21
6-1
6-2
E-l
Table No.
3-1
3-2
3-3
3-4
3-5
3-6
3-7
3-8
3-9
3-10
3-11
3-12
3-13
3-14
8-1
8-2
9-1
ILLUSTRA nONS (Cont)
Title
Core Memory Regulator Board (G8018)
Limited Function Panel .....
KC8-AA Programmer's Console
Paper Tape Leader ....... .
LT33 Teletype Controls
..... .
PDP-8/A Electrical Connection
TABLES
Title
PDP-8/A Computer Assemblies . . . . . . . . . .
PDP-8/A Computers, Dedicated Omnibus Slots
....
KK8-A (M8315) Central Processor Unit Switch Settings
MS8-A Read/Write Memory Switch Settings
MR8-A Read Only Memory Switch
SettLl1gs . . .
MM8-AA 8K Core Memory Jumper Installation .. . . . . .
MM8-AB 16K Core Memory Jumper Installation
DKC8-AA I/O Option Board Switch Settings, C-Etch Module
DKC8-AA Option Board Switch Settings, D-Etch Module . .
Auto-Restart Select Switch Settings .. . . . . . . . . . . .
Bootstrap Select Switch Settings for ROMs Labeled 87A2 and 88A2
Page
· 3-28
· 3-29
· 3-30
6-2
6-3
E-l
Page
3-2
3-3
· 3-10
.. 3-12
· .. 3-14
..... 3-16
· .. 3-16
· 3-20
..... 3-21
.. 3-23
· 3-23
· 3-23
· .. 3-24
Bootstrap Select Switch Settings for ROMs Labeled 158A2 and 159A2
Bootstrap Select Switch Settings for ROMs Labeled 156A2 and 157A2
Bootstrap/Auto-Restart Switch Settings . . . . . . . . . . . . .....
Bootstrap Switch Settings for ROMs Labeled 87 A2 and 88A2 (E82 and E87)
Bootstrap Switch Settings for ROMs (E82 and E87) Labeled 158A2 and 159A2
3-24
8-8
8-8
9-1
Basic PDP-8/A Troubleshooting ....................... .
v

CHAPTER 1
INTRODUCTION
There are two basic types of computers in the PDP-8/A family. The first type is the PDP-8/ A, which uses
semiconductor memories (MS8 and MR8). The second type
is represented by a series of computers, each of
which uses 8K or 16K core memory (MM8); this series consists of the 8A400, 8A420, 8A600, 8A620, 8A800, and
8A820 computers. When a reference applies to both types
of computers, the designation "PDP-8/ A" is used.
"PDP-8/A semiconductor" refers to the semiconductor memory computer, while "8A400," for example, refers
to a specific core memory machine and
"8A" refers to the core memory machines in general.
The
PDP-8fA Operator's Handbook includes instructions for packing, unpacking, and installing a PDP-8/A
miniprocessor. All computers and modules are tested thoroughly at DIGITAL's manufacturing facilities before
they are shipped. However, many switches andjumper wires can be arranged
by the customer for specific pur-
poses; furthermore, there
is a need both to verify system interconnections and site preparations, and to detect
possible hidden damage incurred during shipping. Consequently, a number
of initial operating tests are also
included in this handbook.
A
PD P-8 /A basic system can comprise a variety of components. The following three basic systems are the most
common:
1. A basic PDP-8/A,*a memory, and a Limited Function Panel. (This computer does not include a KM8
Extended Memory Option module and, hence, must be a PDP-8/A semiconductor.)
2. A basic PDP-8/A, a memory, a Limited Function Panel, a KM8 Extended Memory Option module,
a DKC8-AA
I/O Option module, and a Programmer's Console. (Chapter 5 describes operating tests
for this arrangement.)
3. A basic system as described in 2, but accompanied by a teletypewriter and diagnostic** programs.
(Chapter 7 describes operating tests for this arrangement.)
*A basic PDP-8fA is defmed as a Central Processor Unit (CPU) and a chassis assembly (chassis, Omnibus, and power supply).
**Diagnostics are test programs written
to fmd faults in the logic. The PDP-8fA programs are supplied on paper tape. Diagnostic pro-
grams are optional and may be ordered from the Software Distnoution Center, 146 Main St., Maynard, MA, 01754.
1-1

2.1 UNPACKING INSTRUCfIONS
CHAPTER 2
PACKING AND UNPACKING INSTRUCTIONS
All PDP-8 fA computers are packaged in two containers; the inner container holds the computer and some kind
of protective material. The steps in this section are sufficiently general to apply to any PDP-8fA.
To unpack the PDP-8fA computer, proceed as follows.
i. Open the outer carton and remove the inner carton.
2. Open the inner carton.
3. Carefully remove the cardboard from the top and sides of the computer.
4. Carefully remove the computer from the box.
5. Inspect the computer for damage. If the computer is damaged, notify the carrier immediately.
6. Unpack any other boxes included in the shipment.
7. Check that all equipment, software, manuals, etc., are present as specified on the shipping list inside
the carton.
8. Save the cartons and packing material to use if the PDP-8fA is later repacked.
9. Refer to Chapter 4 for PDP-8fA installation procedures.
2.2 PACKING INSTRUCTIONS
Two types of packages are used for the PDP-8fA computers. The type used and the applicable packing instruc-
tions depend on the type of PDP-8fA chassis assembly.
2.2.1 BA8-C Chassis Assembly
The 8A420, 8A620, and 8A820 computers use a BA8-C chassis assembly (20-slot Omnibus). Figure 2-1 illustrates
the packing procedure. The computer is first placed in the inner container (9905417), the empty space is filled
with plastic protective material (AIR CAP, SD-120), and the container is sealed. The sealed inner container is
surrounded with protective foam material which is then enclosed by the two telescope caps. Finally, the package
is secured by two plastic straps.
2-1