Digital PDFs

XX-54C44-B7

2000

78 pages

Original

1.3MB

Document:	PDP-12 Hardware Student Guide Number 1 Adjustments, Diagnostics & Troubleshooting
Order Number:	XX-54C44-B7
Revision:
Pages:	78
Original Filename:	http://bitsavers.org/pdf/dec/pdp12/training/PDP-12_Hardware_Student_Guide_Number_1.pdf

OCR Text

PDP-12 HARDWARE

STUDENT GUIDE NO. 1
(Adjustments., Diagnostics

Troubleshooting)

Educational Services

CONTENTS

PDP-12 Lab #1

2 Hours

A. Loading the RIM Loader
B. Checking the RIM Loader
C. Loading the BINary .·Loader
D. The Use of Checkerboard Low and High to
Check Memory

E. How to Tune Memory
F. Program Development
II.

PDP-12 Lab //2

4 Hours

A. First Period
1. Scoping Processor Timing
2. Scoping Memory Timing

B. Second Period
1. Scoping Manual Timing
2. Troubleshooting (as time permits)
III.

PDP-12 Lab i¥3

2 Hours

A. Understanding the Front Panel Indicators
B. Use of Paper Tape Diagnostics in Locating
Machine Failures
C. Troubleshooting (as time permits)

IV.

PDP-12 Lab #4

2 Hours

A. TU-55 Alignment, Torque and Brake Adjustments
B. Troubleshooting Processor Problems

PDP-12 Lab //5

2 Hours

A. Dial Lecture
VI.

PDP-12 Lab #6

2 Hours

A. Do Key Operation
B. Use of Linc Instructions
VII.

PDP-12 Lab /f7

2 Hours

A. TU-56 Adjustments
B. Troubleshooting Processor Problems
VIII.

PDP-12 Lab #8

2 Hours

A. -Program Debugging
B. Program Development

c. Troubleshooting Processor Problems
IX.

PDP-12 Lab #9

2 Hours

A. Using Mark 12
B. Use of Tape Instructions
X.

PDP-12 Lab #lO

2 Hours

A. Scoping Linc Tape Timing
B. Scoping the Mark Track
C. Linc Tape Bugs (as time permits)
XI.

PDP-12 Lab #11

2 Hours

A. Tape Delay Adjustments
B. Troubleshooting the TC-12

XII.

PDP-12 Lab #12

2 Hours

A. Use of Tape Diagnostics
B. TC-12 Troubleshooting
XIII.

PDP-12 Lab #13

2 Hours

A. Calibration of AD-12
B. Troubleshooting AD-12
XIV.

PDP-12 Lab #14

2 Hours

A. VR-12 Adjustments
B. VR-14 Adjustments
C. Troubleshooting the VC-12

XV.

PDP-12 Lab #15

2 Hours

A. KW-12A Diagnostic Usage
B. KW-12A Troubleshooting

XVI.

PDP-12 Lab //16

4 Hours

A. PDP-12/10 System Troubleshooting

B. PDP-12/20 System Troubleshooting

c. PDP-12/30 System Troubleshooting
D. PDP-12/40 System Troublesho6ting

PDP-12 LAB NO. 1 OUTLINE
Time: 2 hours
-

Loading the RIN! Loader

Checking the RIM Loader

Loading the Binary Loader

The Use of Checkerb6ard Low and High to Check Memory

How to Tune Memory

Program Development

PDP-12 IJ\B JOB SHEET 1/1-1

TITLE:

Loading the Rim Loader

OBJECTIVE: To insure th~t all students are capable of
manually inserting Rim Loader into core
successfully. ·
PROCEDURE: 1. The student should read information
sheets 1, 2 and 3.
2. Using the procedure described in information sheet 4, load the rim loader
as listed in info sheet 3.

3. Go to Job ¥1-2.

PDP-12 Ll\B JOB SHEET .#1-2

TITLE:

Checking the Rim Loader

OBJECTIVE:

1. To insure that the rim loader is correctly
loaded into core.
2. To further usage of the keys Exam and Step
Exam.

PROCEDURE:

Use the nrocedure described in information
sheet 5 and check the rim loader.
Upon completion of this exercise
Go to Job Sheet #1-3

PDP-12 LAB JOB SHEET #1-~

TITLE:

Loading the Binary Loader

OBJECTIVE:

To insure that all students understand the
purpose of the binary loader and can successfully load the binary loader.

PROCEDURE:

1. Obtain a binary loader paper tape from the
instructor.·
2. Compare the format of this tape to the format
as described in information sheet ¥2 binary
format.

3. Read info sheets 6, 7, 8 and 9.
4. Use info sheet #9 and load the binary loader
paper tape.

5. Upon successful completion
Go to job sheet #1-4

PDP-12 LAB JOB SHEET #1-4

TITLE:

Using Checkerboard Low and High to Check Memory

OBJECTIVE:

1. To insure that Rim and Binary loader have
been used properly.
2. To introduce the student to paper tape
diagnostics.
). To insure that the memory stack is reliable
before the memory tuning exercise.

PROCEDURE:

1. Obtain paper tapes, checkerboard (Low and
High) and their associated write-ups from
the instructor.
2. Using the procedure descr~bed in info sheet
#10, load and run both programs.
). Upon completion
Go to job sheet #1-5

PDP-12 LAB JOB SHEET #1-5

TITLE:

How to Tune Memory

OBJECTIVE:

To insure that all students can properly tune
memory on the PDP-12.

PROCEDURE:

Perform this memory tuning exercise by the
procedure described in section 4.1 through
4.2.2 of the PDP-12 Adjustment Procedure
manual.

PDP-12 LAB JOB SHEET 71-~

TITLE:

Program Development

OBJECTIVE: To develop the confidence of the student in
his ability to successfully program a processor.
PROCEDURE: Write a program, using LINC or 8-mode
instruction, that detects the number of 4K
fiel~present in a processor.
At the completion of the program, type "This processor
has _ _ 4K Fields", then HLT.
Show this program to the instructor for
technique development suggestions.
Save the program for further use.

FLD1.'I CHI\ RT

RIM LOADER PROGRAM

f/rr; /1w11n~r(

Qr<>. ft-

--~-

Rofu+e

··---. ·-------

Pt~ee.~ le~+
Si#-i '"' ~,,~ hi+

~-------------~N~O~__J

·s fo "" Ac · .:-

"--_.., (A OD R $.t;S)

_ _. . . . ._ _ ______.,

/t;MP

j
l

INFORMATION SHEET #1

PAPER TAPE FORMATS

CHANNELS
876~4

Data are recorded (punched} on paper tape by groups of holes arranged

321

•
e e e e e • e e e

4-- COLUMN

in a definite format along the length of the tape. The tape is divided

•

into channels which run the length of the tape, and into columns which
extend across the width of the tape as shown in the adjacent diagram.
The paper tape readers and punches used with the PDP-8/l computers

•

accept 8-channel paper tape. The various formats are briefly explained
and identified below.

Leader/frailer Format
Leader/trailer tape is used to introduce and conclude the object program
when punched on paper tape. Leader/trailer tape can be recognized by
a consistent channel 8 punch only as shown in the adjacent diagram.

SPROCKET
HOLE

•

•
•
•

•
•
•
•
•

•
•
•
•

•
•
•

INFORMATION SHEE'l' #2

••••••••
•
••
••• •
•
·• • • •••
• •• •
•• ••
•• •
••••• •••
• •• ••
•• ••
••
••••••••
•••• •••
•••
••••

Paper tape punched in RIM format can be identified by the absence of a ,
channel 8 punch, and by a channel 7 punch in every fourth column. The
channel 7 punch indicates the start of a line of coding, and that (the
first) col.umn and the second column contain the location and the third

USASCIJ (USA Standard Code for Information Interchange) format uses

symbol) as shown in the adjacent diagram.

•

•••••
••• •
• ••
•

(two columns per instruction) or data of succeeding locations.

13
10

77
00
77
07
00

00
,7
32
50
00
00

•
• ••••
•••••••
•
••••••
•••••••
••
•
•••• •••
•
•

02
56
77
01
76

CONTENTS
LOCATION

00
00

an occasional channel 7 punch, and frequent sections of blank tape.

a change in origin, and subsequent columns contain the instructions

13
11
77

CONTENTS
LOCATION

al I eight channels to represent a single character (letter, number, or

The channel 7 punch denotes an origin of a program or subprogram or

12
77

•• • • •
•• ••
•• •• •
••
•• •
• •
•• •• •
•• • • ••
• •
••
•
•• •
••
••
••
•• • • •
•• •• •
• •
•••
••
• • • •• • • •
•• •
•
• • • •• • •
••
•

USASCII Format

LOCATION

and fourth columns contain the contents of the location.

Binary format can be recognized by the absence of a channel 8 punch,

77
61

.. ..

RIM Format

Bi nary Format

CHANNEL 7

CONTENTS
LOCATION
CONTENTS
LOCATION

324

310
31,

323
240
3, 1
323
240
301

323

s
c

303
3,,
31 I
240
306

317

322

315
301

324

ORIGIN
INSTRUCTION
INSTRUCTION
iNSTRUCTION
INSTRUCTION
INSTRUCTION
INSTRuCTION

00
77
60

INSTRUCTION

01
77

INSTRUCTION

45
77

INSTRUCTION

INFORIV'J\TION SHEET

¥3

' READ-IN MODE (RIM) LOADER

PURPOSE

The RIM Loader is used to load into core memory programs punched on paper
tape in RIM format, e.g., the Binary Loader. (See DEC-08-LR.AA-D for
details.)

STORAGE
REQUIREMENTS

RIM requires locations 7756-7776 (21

RIM is loaded (toggled) into core memory using the console switches. RIM

locations). Starting Address=7756.

can use either. the low- or high-speed readers when loading RIM coded
program tapes into core. The locations and corresponding instructions for
both input devices are Ii sted be Iow.
Instruction
Location

Low-Speed Reader

High-Speed Reader

7756

6032
6031
5357
6036
7106
7006
7510
5357
7006
6031
5367
6034
7420
3776
3376
5356
0000

6014
6011
5357
6016
7106
7006
7510
5374
7006
6011
5367
6016
7420
3776
3376
5357
0000

7757

7760
7761
7762
7763
7764
7765
7766
7767
7770
7771
7772
7773
7774
7775
7776

INFORMATION SHEET #4

ln1t1olize

Set*
OF•Onored Field
IF•Dnired Field

Set SR•7756

Depress
LOAD ADO
• DEC lope ustrs should
load RIM into field O

Set SR•Firsl
I nstructoon

Actovolt DEP

Set SR• Next
lnstrucl1on

Activate DEP

RIM Is Loaded

Loading the RIM Loader

5
INFORMNrION SHEET #5

ln1t101o1e

Set
OF"• Correct F"oeld
IF"• Correct F"oeld

Set SR• 7756

Depress LOAD ADO

Depress EXAM

Yes

Set SR•MA

Depren LOAD ADO

S.t SR•Corrtct
Instruction

Dtprtn OEP

RIM Is Loodtd

Checking the RIM Loader

INPORfv:J\TION SHEET //6

( BINARY (BIN) LOADER

PURPOSE

The BIN Loader is used to load into core memory binary coded programs
punched on paper tape. When in core, BIN can be destroyed only by the
user's program because DEC's programs (excluding Disk Monitor) do not
use the last page of core (location 7600-7777). ~ee DEC-08-LBAA-D
for detai Is.)

STORAGE
REQUIREMENTS

BIN occupies locations 7625-7752 and 7777 (123 locations). Starting
8
Address=m7

RIM is used to load BIN into core.

BIN must be loaded into the same field

as RIM, and the input device (low- or high-speed reader) must be that which
was selected when loading RIM.

INFOHl\.NrION SHEET /17
Example of Binary Loader Format

Tape Channel
87 654 321

Channels 8 and 7
Indicate

Program
Proper

10 000

000

leader

01 000 . 010
00 000 . 000

Origin

In octal the origin 0200.
wi I I start at 0200.

00 111 . 010
00 000 . 000

Contents of 200

Yes

The command 7200 or C LA.

00 011 . 010
00 111 . 110

Contents of 201

Yes

The command 3276 or DCA Z 076.

00 111 . 100
00 000 . 010

Contents of 202.

Yes

The command 7402 or HLT.

00 000 . 100
00 010 . 010

Checksum

The program determines that these
two characters are the checksum
since trailer follows.

10 000

Trailer

000

The octal checksum in this example is 0422.

102
000
072
000
032
076
074
002

Notes

Note that this is the fol lowing sum:

Origin
First word
Second word
Third word

422
Memory Extension Usage
Loading - It is recommended that the Binary Loader exist in field 0. This will insure a permanent program lining around location 7754 and 7755 which are used for TCOl DECtape. The loader
will of course exist in any field, though caution must be taken not to use location 7754 and 7755 in
field 0. This applies only to DECtape users. Also, when the proper field is chosen it should be noted
that the RIM Loader must already be in that field.

INPOHMJ\TION SHEET

/18

Binary Loader Loading Procedure For Extended Memory Users
a.

Place the Binary Loader tape in the reader.

Place the proper FIELD in the INSTRUCTION FIELD REGISTER when putting the

starting address of the RIM Loader (7756) in the SWITCH REGISTER.
c.

Press the LOAD ADDRESS key.

Press the ST ART key.

Start the reader.

(ASR 33 - press READER CONTROL to start, 750 High-Speed

Reader - should already be ready to start).
Operation and Usage For Extended Memory Users
a.

Place the tape to be loaded (tape must be in binary format) in the reader.
When using the ASR 33, make sure reader is on-line. When using the 750, make

sure reader is on and tape is positioned with leader/trailer over read head.
b.

In the DATA FIELD REGISTER place the field in which the program is to be loaded.

In the INSTRUCTION FIELD REGISTER place the field that the binary loader is in.
Place starting address of the Binary Loader (7777) in the SWITCH REGISTER.
c.

Press LOAD ADDRESS key.
When using the 750, change the SWITCH REGISTER to 3777 (bit 0 = O). Omit

this step if using the ASR 33.
d.

Press console START key.

INFORMJ\'rION SHEET #9
FLOW CHARTS

Loading Binary (BIN) Loader

DEC Library Tape No: Digital-8-2-U
CHECK THE RIM
LOADER IN MEMORY,
IF NECESSARY
.,._~~~~~~~~~~~~~~~~~~~~~~~~~~~~~---,

PUT SWITCH ON ASR-:n
READER TO FREE ..
BE SURE ASR-33
SWITCH IS ON LINE

PUT THE BINARY
LOADER TAPE INTO
READER WITH LEADER
CODE OVER THE READER
HEAD-~ BLANK TAPE

PUSH ASR-33
SWITCH TO START

ASR- 33 SWITCH
IS ON LOCAL
SWITCH TO LINE

PRESS START KEY

TURN OfilTO LINE

•• THIS ALLOWS THE TAPE TO FIT SMOOTHLY
OVER THE READER HEAD ANO THE SPROCKET
WHEEL TO RUN FREELY.
EXTENQEP MEMORY USERS
AFTER PROGRAM READS
IN, WAIT UNTIL ONLY
BIT "0" IS ON IN
ACCUMULATOR (i.e.
TRAILER CODE OVER
READER HEAD!

PRESS STOP KEY ON
ONSOLE. MOVE ASR-33
ADER SWITCH TO FRE
PROGRAM IS LOADED

G) CHECK FOR RIM LOADER IN PROPER FIELD
~ PUT FIELD IN INSTRUCTION FIELD
REGISTER

INFORMJ\TION SHEET #10

Load BIN

Set
Or•0.1ired Field
rr •f'1eld Of BIN

Set SR• 7777

0.prHI LOAD ADO

Set SR• 3777

T1.1rn TTY To LINE

P1.1t Tope In HSR

P1.1t Tope fn LSR

OeprHI START

Set LSR To START

OeprH1 CONT

Object Tope

Loaded

Loading A Binary Coded Object Tape Using BIN

PDP-12 Lab No. 2 Outline

4 hours
f.'IRST PEHIOD

lo Scoping Processor Timing
Job #2-1
2. Scoping Memory Timing
Job #2-2

SECOND PERIOD
3. Scoping Manual Timing
Job #2-3
4. Bugs (as time permits)
Troubleshooting Memory Problems, (as time permits)

PDP-12 LAB WOl~K SHEET #2 -1

TITLE:

Signal name, Pin location, and Page reference chart.

OBJECTIVE:

To aid the student in the generation of a cycle time
chart.

PROCEDURE:

1. With reference to signal, both numbered and named,
on worksheet Noo 21 A, draw in the waveform as seen on
the scope with relation to CPTPl as the triggering
source, on Worksheet Noo 2-lB
2. Scope settings

o2us/Cf\1 sweep
Sync Ext
Scope Pos
Sweep Alt

3o On chan. 1 look at TPl

On chan. 2 look at the time relation to the numbered
signals.
4. At location ¢¢¢¢ place a

JM~.

Upon completion go to Job Sheet #2-2

PDP-12 LAB JOB SHEET #~-1

TITLE:

Generation of a processor cycle time charto

OBJECTIVE:

To aid the student.in generating a processor cycle
timing chart, and in understanding processor cycle
time with reference to CPTPl.

PROCEDURE:

Use the procedure described in Lab Worksheet #2-1.
Upon completion, go to Job Sheet #2-2

PDP-12 Lab Worlcshcet //2-lA

Sirnal Nu!:1bcr

2
3
4
5
6
7
8
a
./

ll
12
13

15
16
17
18
19
20
21
22

Jl2 El
J.139 Fl
1(15 N2
J06 El
J21 El
Jl0 Cl
H06 Fl
J01~ Nl
J07 El
El4 S2
J0'6 Sl
J21 Ll
J06 J2
J0l+ L2
J03 P2
J¢l+ Kl
J0'3 D2
H0'9 Jl
H0'9 Fl
H0'3 Jl
K0'6 Bl
H0'7 Fl

Pi.n L8caticm

CPT
CST
CPTP
CPT
RCL
CPTP
CPTP
CPT
CPTP
MCT
CPT
RCL
CPT
CPT
CPT
CPTP
CPT
CPTP
CPTP
CPTP
CPS
CPTP

~('~

i!IBET f/2-lB

•

Ons
l

CYC DOlJE

::E:: IBLE

TSl o

LOAD :.:A

---+----------------·"···----+-·---+---+-----+---+----t----+-----+----+----+---+-----+--4--~----+---

~PlO
r.

TS2

T?2

STROBE
., .,

TS3
LOAD MB

., J
·- ._)

TP4

TS5

-'-''

r:.

TPSS

O?F PAUSE

TP5

TP50

LTP5

TPl

TP3

1 c::::
___,

PDP-12 Lab Job Sheet
#2-2

TITLE:

Generation of a memory cycle time chart

OBJECTIVE:

To aid the student in generating a memor;/ cycle
timing chart and, in understandine memory cycle
time with rcfererice to Mem Start.

PROCEDURE:

Draw a timing chart of memory c;/cle time using
WorkshE:et //2.
Upon completion, go to Job Sheet #2-3

PDP-12 Tab Worksheet #2-2

TITLE:

Memory timin~ chain

PROCEDURE:

Draw a waveform chart of the sic;nals named below
usinr; the scope.
Reference all time relation to start memory.
All sicnals can be located through the MCT page.
The chart is calibrated at 200 ns/dev.

TPl
(St.Memory)
p 'd

Inhibit
Write
Mem Done

PDP-23 Tab Job Sheet #2-3

TITLE:

Manual timinc functions

OBJECTIVE:

aid the student in his understanding of the
PDP-12 manual timinr, chain and the operation of
the key stop exam.

PROCEDURE:

1. Tape Ml, Nl, ·Pl, Rl of Mll7 in slot L22 removinr,
all console inputs from Schmitt trigger. CST(A,7)

':': >

2. Tape Cl of Mll3 in slot L40 removin~ IO preset
or PWF restart from CST¢ AC. CST (C2, 7)

3. If the processor has the KP-12 option, remove
the PWF card.
If the processor does not have the KP-12 option,
there should be a connection between K33Vl and
K32R2. Tape K33Vl removing +3v from K32R2.
4. Using a jumper wire of sufficient length,
connect at K32R2 your selected TTO clock rate on,
M452 in slot N¢8 pin K2 (220H ), N2 (440 H ),
J2 (880H ).
5. Tape the key step exam to the one state.

6. Referring to the manual functions flow diagram

observe all operations with the oscilloscope and
cenerate a tir.1inr; chart for the kc;/ step exam from
the beginning of manual timing to the end of processor timing using Lab Worksheet 2-3A.

PDP-12 Lab Worksheet /f2-3A

PROCEDURE:

Scope setun
Ext. tricger
Mode alternate
Sweep rate

2 us/cm

Manual triccer setup
Key

examine manual- timing
Tape the key step exam onto console. On the est
print remove the connection between Mll7 Sl slot
L22 by placinG a piece of tape over the pin.
Connect a jumper wire bet,·1een (TTO TTI clocl-c H Re)
and input to M700 K32 L32 pin KR2.
Generate a timinc chart, as in Jobs 21 and 2c, for
the key step exam.

POP-12 Lab #3 Outline

1. Understanding the front panel indicators
~.

Use of paper tape diagnostics in locating machine failures.

3. Bugs (as time pennits)

PDP-12 Lab Job Sheet #3-1

TITLE:

Understanding the front panel

OBJECTIVE:

To insure that the student will learn to use the front
panel indicators as aids in system troubleshootingo

PROCEDURE:

Complete the steps described in Lab Worksheet #3-1
Any discrepancies should be corrected at this time.

Upon completion go to Job Sheet #3-2

PDP-12 Lab Worksheet #3-1

Console Checks - Assumin9 a cold start, check the following console functions.
If any malfunctions occur, repair the problem before continuing with the procedure.
Refer to Chapter 4 - PDP-12 Adj Procedures - for appropriate adjustments.
1.

Power on

Are IR bits o, 1, and 2 set (on), and in 8 Mode; is RUN
off*, and is power up to specification (refer to Paragraph 4.1)?

2•

I /0 PRESET

Does the AC clear? Does it set the INST FIELD and .DATA
FIELD to 2 and 3, respectively? Do the INSTRUCTION REGIS_
TER bi ts o, 1.. and 2 set to the one st ate (on)? Can both
modes be selected? Do all other indicators remain unchanged?

FILL

Do the RIGHT SWITCHES transfer to

the MB?

Do the LEFT

SWITCHES transfer to the MA?

EXAM

Do the LEFT SWITCHES transfer to the MA? Do the contents of
the location addressed by the MA transfer to the MB?

FILL STEP

Do the RIGHT SWITCHES transfer to the MB? Do the RUN and
INT PAUSE lights illuminate? Do the contents of the MA
increment? Do the contents of the new location addressed
by the MA transfer to the MB?

STEP EXAM

Do the contents of the MA increment? Do the contents of the
new location addressed by the MA transfer to the MB?

AUTO RESTART

Can FILL STEP and STEP EXAM be auto-restarted?
AUTO light illuminate?

While depressing both the AUTO and the FILL STEP keys, sequentially set
the AUTO RESTART DELAY - COURSE (starting at position 4) to position 3;
then to position 2, then to position 1. Note that the MEM::>HY ADDRESS
register fills (counts up) at a slower rate as the AUTO RESTART DELAY COURSE s.elector is moved through the four positions.

Examine memory for any bits that may be picked up.

10.

Set RIGHT SWITCHES to 7777 (all l's), repeat steps 8 and 9.

11.

Examine memory for any bits that may be dropped.

12.

Depress SING STEP key.

13a

Depress START 20a

ao
b.
c.
d.
14.

Does the MA
Does the PC
Does the MB
Does the IR

= 0020?
= 0021?
= 7777?
= 7777? ( dependin <J on contents of location 0020)

Reset SING STEP; clear memory; depress STOP key.

*Unless the KP12

Does the

~nver

Fail Option is installed.

PDP-12 Lab Worksheet #3-1

15.

Depress START 400.
a.
b.
c.
d.
e.

16.

Page 2

Does
Does
Does
Does
Does

the MA
the PC
the MB
the MA
the IR

= 0000?
= 0401?

= 0000?

Reset STOP; depress CONTo
a. Does the RUN light illuminate?
b. Do the MA and PC cycle through 4K of memory?
c. Does the AC remain closed?
d. Are the FETCH and EXECUTE indicators set (on )7

17.

Set and reset STOP key; depress I/O PRESET key to LINC Mode; fill LINC
memory field 2 with 0016s (NOP)o

18.

Depress·· the STOP key.

19.

Depress START 20.
a.
b.
c.
d.

20..

Does
Does
Does
Does

the MA = 4020?
the PC = 4021?
the MB = 0016?
the IR :: 0016?

Reset the STOP key; depress CONT.
a. Does the RUN light illuminate?
b. Do the Ml\ and PC cycle throuoh lK of memory?
c. Does th0 AC remain cleared?

21~

Depress SING STEPo
Does the computer stop?

22.

Depress CONT repeatedly.

Does the computer stay in the FETCH state?

230

Depress and hold AUTO RESTART; depress CONT; release all switches.
Does
the computer cycle through lK of memory at a rate determined by AUTO
HESTAIIT DELJ\Y, COARSE and FINE adjustments?

24.

Set several different instructions into the LEFT SWITCHES; depress DO.
{Be sure that the CP is in the proper mode for each instruction). Does
the CP react to each instruction as expected? If the CP performs these
operations successfully, manual timing, memory timing, and CP timing are
"in the ball park." Proceed with system troubleshooting.

PDP-12 Lab Job Sheet #3-2

TITLE:

Use of paper tape diagnostics

OBJECTIVE: To familiarize the student to the use of paper tape diagnostics
as an aid to troubleshooting.
PROCEDURE: Read lab handout #3.-2 Upon completion ask the instructor to
install a problem in your processoro
Determine the failure through front panel indicators or paper
tape diagnostics.
Document all problems using PDP-12 Failure Documentation sheeto
Upon completion, ask the instructor for another problemo

GOOb LUCK!

LAB ll/\N IX)UT

#:, -2

M:\intcnance Test Programs
T:\ble 1-2 lists approximately 25 processor test programs designated MAINDEC;
collectively, these programs provide a complete check of th0 logic.
Functionally, the programs fall into two categories: Diagnostic and reliability.
The diagnostic tests isolate the guine 00/no-90 type of hardware failures that
are easily reco']nizable. The reliability programs isolate failures that are
more difficult to detect because they are marginal in nature and/or occur infrequently· or sporadically. The family of test programs are written so that, when
run successively, they test the processor, beginning with small portions of the
hardware and gradually expanding until they involve the entire system.
The test programs are made up of numerous self-contained routines. In those programs that are diagnostic in nature, each routine is involved with a specific
circuit or logic function.
In the simplest form, for example, a separate routine
is used to check each leg of an AND gateo When the diagnostics have been run to
completion, the processor has been exercised to the extent that it has been proved
capable of executing all instructions. However, such proof is conditional because
it is based on the execution of instructions using pre-established constants as
operands.
Further tests are necessary to establish that the co~puter properly executes inst ~uctions using operands and various combinations of operands other than those
used in the diagnostics. The reliability test programs provide this additional
testing. Primarily, each routine in the reliability test programs establishes a
loop whereby a specific inst ruction or group of instructions is ·repeated many
times.
Each repeat is executed using operands whose magnitudes are established
by a pseudo-random number generator, or a binary upcount. This procedure makes
certain that machine capabilities are checked under a maximum number of unique
con di 't ions.
When an error is detected with diagnostics, the program halts at the end of the
unsatisfied routine. The reason for the halt may then be determined by using
the console controJ_s and indicators, maintenance switches, error type-outs on
Teletype, and the program listings included in the software package. The use of
the data switches for selecting error indications is defined in the MAINDEC writeups provided with the software packageo

Lab

JI andou t

# '3-2/\

DIAGNOSTIC PRCGRAMS
Name

Mnemonic

DEC Number

JMP SELF Test

JMPSELF

MAINDEC-12-DlBA

Memory Addressing Test

Rel<w Test

HELAYTST

MAINOEC-12-D8AB

Tests the Operation and Transfer
to/from the AC of 6 Relays

Tape Register Test

ADDRS12

MAINDEC-12-03/\C

Tests Tape Control Logic and Interregister Transfers

Memory Data Test

MEMDATA

MAINDEC-12-DlEA

Tests Memory Reliability

Memory Address Test

ADDRS12

MAINDEC-12-DlCA

Tests Memory Addressing (LINC Mode)

VR12 Display Test

DISPTST

MAINDEC-12-D6BJ\

Tests Display System Using DIS and
DSC Instructions

Instruction Test lA

INSTl

MAINDEC-8/I-0013

Tests AND, TAD and Operate Instructions

Test 2

INST2

MAINDEC-8/I-LX)2D

Tests Auto Indexing, Indirect Addres
sing, and I:x:R Instructions

Instruction Test 2B

INST2B

MAINOEC-08-0028

Tests 2's Complement ADD(TAD) and
Rotate Instructions

Random ISZ

ISZ

MAINOEC-08-0078

Tests ISZ Instruction (LINC Mode)

Random JMP

JMP

MAINDEC-08-0048

Tests JMP Instruction (LINC Mode)

Random JMP-JMS

JMP.JMS

M.A INDEC-08-00SB

Tests JMS Inst ruction (LINC Mode)

Checkerboard Low

CBL

MAINDEC-08-DlLl

Tests Lower Memory Susceptibility
to Noise

Checkerboard Ei~h

CBH

MAINDEC-08-DlL2

Tests Upper Memory Susceptibility
to Noise

Memory Address Test,
High

ADDHSHI

MAINDEC-08-DlBl

Tests High Memory Address Selection
Logic

Memory J\ddrPss Test,
Low

ADDI?SLO

MAINDI~C-08-D1B2

Tests Low Memory Address Selection
Logic

On/Off Test

ONO FF

MAINDEC-08-DlAC

Tests Memory Data Validity after
Simul~ted Power Failure

Trl0typc• T0st P;trt 1

TTYl

MAINDEC-08-D2PE

Tests Teletype Instruction Control
Logic

Trl0typc• T0st Part 2

TTY2

MAINDEC-08-D20D

Teletype Test Control

Pro~~rarn

~uction

Use

Lab Handout #1-2A

Page 2

Instruction Test 1

CPTSTl

MAINDEC-12-00BA

Tests Instruction (LINC Mode)

Inst ruC"tion Tc-st 2

CPTST2

Ml\INDEC-12-00AB

Tests SKIPs and Data Handling
(LINC Mode)

A-D Test

ADTST

Ml\INDEC-12-D6CB

Tests A-D Converter and allows
Calibration of Preamplifiers

PDP-12 Lab #4 Outline

TU-55 Alignment torque and brake adjustment

Troubleshooting Processor problems

PDP-12 Lab Job Sheet #4-1

~ITLE:

TU-55 Adjustments

OBJECTIVE:

To insure that all students can successfully perform
the required adjustment of the TU-55 Tape Transport

PROCEDURE:

With the aid of a scope, perform the adjustments prescribed in Information Sheet #4-1
Upon completion, ask the lab instructor to insert
failures pertaining to Lab #4. Document all troubleshooting using PDP-12 Lab Failure Documentation Handout.

PDP-12 Lab Information Sheet #4-1

~ROBLEM:

Inconsistency in Adjustment of TU-55 Brakes and Torque

Brake Adjustment

Energize the brake for at least 5 minutes.
This will insure that the following adjustments will
not be too tight, causing brake drag when the unit
warms up.

a·..

With power off bring the brake shoe into the brake
solenoid, then bring it back to the point at which
the show rotates free.

The brakes may be considered properly adjusted when
repeated energizing produces a minimum of audible
"click" and yet the shoe doesn't rub on the high spot.
If this cannot be accomplished it is probably due to
a shoe with too much run out. The ideal situation is
to have no "click" and no drag.

Torque Adjustment
A.

Without tape on the transport, apply idle torque to
the motor. With a scope, observe the bottom tab·
terminal on the rear of the G850. Set the scope to
2 M.S./c.M. at lOv/CM. The waveform should be similar
to what is shown in Fig. 1. If it is not, make the
necessary adjustments shown in Fig. 2.

Repeat step "A 11 with trailing torque applied to the

motor .
c.

Run a start - stop - turn around test, and adjust
delay {Loe .AB4) until there is a minimum of tape slap.
This should be approximately 80 M.So to 90 M.S.

nus Tl"" E lS ADJUSTED

....._..166 ~VlA

THE cSSoo ..

0) .lov
M
10;1 PROBE
(BOTTOM ~TA 9

S.C.R. TOR.NS "\. _

OFF

sw~o-~tt~. /cM

ON 6-8501

TME' 4 M.s. Ao.)UsT-

MEN\ APPL.tes TO

lteA\L.f Mtq A~ C
I DL.E to~que. S.
Fl G, l

Fl~.

AMP. CDAJ~.

/IM PHE~O '- PL.\J '1 ~
f EA~ o ~ Mo DU '-

~8Sl RG'L~Y
\N TUS S
LO~ ~Bl

Ht:AD Cot-JAJ,

AF ~ A\+

T.T.

-r'(PE 453
~U>Pt ~·

'J-1 PR.6B£

AN~ AP

AlJ -

,. l=

Ml.

.Of 1-4~J, S"ov CP\P ff?..O M

S 16. LI N e To 9 RO SE 6 NO.

AV~ BD

"' p •

t>3

'"" V I
B...,.,... ~,~ v 1---~-0--Bi::

D2
u,..___

.........._~-

LJ, sH1~
5P

PROBLEM:

Cannot check DECtape Head Amplitude with a Type 453 Scope.

~OLTUION:

Obtain a 1:1 probe and attach a .01 Cap. on the end
of it between the probe sig. lead and the probe case
gnd.
If a ready made probe isn't available use co-ax
cable.

Float the scope gnd, via a 3-prong adapter.

Attach the scope tip and gnd. lead to the points indicated on the attached diagram. If the unit is a 555
or the head cannot be easily selected, then observe the
pins on the head connec.tor.
The scope should be set for 5 M.V./CoM. at about 10 msec
/C.M. A 9-12 M.Vo P-P signal should be observed.
A sinusoidal signal will be observed on the timing track
{ToT.), .however the mark track (M.T.) and data tracks
(Dl, 02; 03 ) will not be perfectly sinusoidal due to the
randomness of the data written.

PDP-12 LAB 11'5

LESSON PLAN

To be Supplied

PDP-12 Lab #6 Outline

2 Hours

Do key operation

Use of instructions

PDP-12 Lab Job Sheet #6-1

~ITLE:

Do key operation

OBJECTIVE:

To insure that, by examples, all students are able to
use and understand the DO key for the various instruction
classes of the PDP-12

PROCEDURE:

Perform an LDA instruction using the four different
IB configurations. Note the way each configuration
addresses memory, using the DO key.

Using the DO key1 perform an STA instruction noting
the way that the four different IB configurations
address memory.

Using the DO key, load a number into the AC from a
Data Field location.

Using the DO key, store the above number in another
Data Field.

Using the DO key, perform the following instruction:
8 Mode:
TAD DIR cpg 50
D.CA IND cpg 50
OSR
L Mode:

IOB,KSF
SET and SET
DIS
AUTO
HLT
,..m.c then RDC

PDP-12 Lab Job Sheet #6-2

lPITLE:

Use of Linc Mode Instructions

OBJECTIVE:

To challenge the students' instruction knowledge and
programming ability by providing each student with a
thought provoking programming problem which, when
solved, will provide him with a greater understanding
of the Linc Mode instructions and therefore selfconfidence in his ability to program the system.

PROCEDURE:

Write a program to add the contents of Loe. 06000-06010,
store their sequential sums in location 00100-00107.
If overflow occurs at any time, stop the addition, ring
the TTY bell once and display the number of words which
have been added before overflow occured in the AC.

PDP-12 Lab #7 Outline

Hours

TU-56 adjustments

Bugs

PDP-12 Lab Job Sheet #7-1

TITLE:

TU-56 Adjustments

OBJECTIVE:

To insure that all students understand the similarities
and differences in the adjustment procedures for
TU55 and TU56.

PROCEDURE:

Perform the adjustments described in the TU-56
Maintenance Manual, Chapter 6.

PDP-12 Lab #8 Outline

2 Hours

l...

Program Debugging

Program Development

Bugs

PDP-12 Lab Job Sheet #8-J

TITLE:

Program Debugging

OBJECTIVE:

Each student will successfully write a program to
display a line on the VR-12 or VR-14

PROCEDURE:

Debug the Display Line program and demonstrate its
operation to the instructor.

PDP-12 Lab Job Sheet #8~2

l1ITLE:

Program Development

OBJECTIVE:

To chal.lenge the student's instruction knowledge and
programming ability by providing each student with a
thought provoking programming problem which, when
solved, will provide him with a greater understanding
of the Linc Mode instructions and therefore selfconfidence in his ability to program the system.

PROCEDURE:

Using the previously developed Display Line programs,
modify the program with a sense switch option to
develop a two-part program:
1.
2.

Line Display
sweeping Line Display

PDP-12 LAB #9 OtrrLINE

Using Mark 12

Use of Tape Instructions

PDP-12 LAB JOB SHEET

#9-1

TITLE:

Using Mark 12

OBJECTIVE:

To ensure that all students understand the purpose and
use of the Mark 12 program and its optionso

PROCEDURE:

Using the procedure described in PDP-12 Lab Handout #9-lA,
mark a virgin tape using all three Mark 12 options and observing front panel indication as each option is running.

PDP-12 LAB HANDOUT

#9-1-A

MARK TAPE, COPY TAPE, PRINT DIAL INDEX EXERCISE
NOTE: See reference to paragraphs (ex.5,2) on pp.
(ex.1-5) in the LAP 6
DIAL Manual •

Initial Starting Procedure
1.

Place dial tape on top unit.
Select unit ~ (8) on TU55 transport.

Mount another tape on the lower transport
Select unit 1
NOTE: a. This is only required for commands AS, LI, QL, and SB
(See 1.8 commands).
b. This is also required when using the Mark 12 program.
c. If this is a new DECtape rather than Linc tape, it must
be'placed on the left hub and an empty spool on the· right
hub. The left spool must now be wound on the right usin9
"LOCAL" and " --.. (SN)".

Set switches on both tape units to "REMOTE" and set unit ¢ (8) to
"Write Enable" o

Set the Mode Switch to "LINC" mode and press "IO PRESET" to preset
Linc IF2 and Linc OF to 3o

Set "LSW" to

¢7~1

and "RSW" to 73~¢o

NOTE: Depressing switch on the panel side (of the switch) is a
and on the operator side equals a 1.

If tape comes off the spool, you didn't wind enough on ito
Turn "REMOTE" switch "OFF", rewind spool with leader and
switch to "REMOTE" again.

Press to "00" switch (memory is initialized by tapes).

When tape motion.stops, press"START 2ti" (starting address of Dial).

Dial Program Selection
1.

Turn A-D knobs 3 (Cursor Control) and 7 (Line Control) fully a~
(See 2.1)

Using the keyboard, type Linefeed (--.,A. "cursor" appears at the
lower left of DISPLAY) DX RETUHN ( J ) to obtain the Dial Index (See 5o4)

9-1A

"LINEFEED" cursor lower left

NOTE:
6.

Select "A" (auxilliary options) and "RETURN"

NOTE:
7.

Do not use LO for PIP -- has an auto loader type PDP & RETURN.

At this point tape to be duplicated should be to transport

Select "D" (duplicate) and "RETURN"

NOTE:

Duplication begins.
Observe tape instruction register on the PDP-12 panel
Tape Instruction Register

a. oeo
b. ••o
c ••••

702
706
707

ROE - Unit ¢ (8)
WRI}
CHK)- Unit 1

"CONTROL 0" together - back to DIAL

Linefeed

cursor lower left

Print Index
1.

LINE FEED

PRINT INDEX

UNIT

comma
(.1UNIT)
Print out occurs

RETURN
Sec.

s.s

¢ (8)

#9-lA

To view the entire index use the following keys:
ACTION

KEY

Forward one frame
Forward one line
Backward one frame
Backward one line

2
Q

w
4.

When the MARK 12 program listing is found, perform the following
steps using the keyboard:
a. Strike key "RETURN & LINE FEED"
1. Return gets you back to DIAL.
2. Line Feed stations the cursor in the lower
left of Display

b. Type
1. "LO"
2. "SPACE"
3. ''MARK 12"
4. "COMMA"

s. "91"

(load)
( L-l

)

(w/no space)

(

6. "RETURN"

)
) MARK 12 instructions should be seen
on the Display.

Refer to MARK 12 program listing (Program Library)
5.

Follow instructions on the Display

Returning to DIAL
lo

Using the keyboard type:
a.

"2"

"LINE FEED"

_NOTE:

Depending on programs used (other than MARK 12) there are
numerous ways to remove the current display, tYPing:
1.
2.
3.

"RETURN" (clears the screen, back to DIAL)
"OONTROL D" (at the same time, gets Dial back)
''CONTROL P" (together, gets you back to PIP)

Copy Tape
1.

"LINE FEED" -- cursor moves to lower left.

Type DX & RETURN" (returns Index)

Locate PIP (peripheral interchange program) in the Index

"RETUllli" back to DIAL

•l

9-lA

"LINEFEED" cursor lower left

NOTE:
6.

At this point tape to be duplicated should be to transport

Select "D" (duplicate) and "RETURN"

NOTE:

Duplication begins.
Observe tape instruction register on the PDP-12 panel
Tape Instruction Register
a.
b.
c.

oeo

••o

•••

702
706
707

RDE - Unit

¢ (8)

WRI~

CHK - Unit 1

"CONTROL D" together - back to DIAL

Linefeed

cursor lower left

Print Index

& RETURN.

Select "A" (auxilliary options) and "RETURN"

NOTE:
7.

Do not use LO for PIP -- has an auto loader type PDP

LINE FEED

PRINT INDEX

UNIT RETURN
comma
{ 1 UNIT)
Print out occurs

Sec. 5 .. 5

¢ (8)

PDP-12 LJ\B JOB SHEET

#<;; -2

TITLE:

Use of Tape Instructions

OBJECTIVE:

To introduce the student to all tape instruction and front
panel indications as each instruction is executed.

PROCEDURE:

Using the Do key, perform each of the below tape instructions
and note all front panel indications during the tape instructi on and at the completion of the instructiono

ROE
RDC
RCG
WRI

WRC

WCG
CHK
MTB

PDP-12 LAB #10 OUTLINE

TIME:

2 Hours

Scoping Linc Tape Timing

Scoping the Mark Track

Linc Tape Bugs (as time permits)

PDP-12 LAB JOB SHEET #10-1

TITLE:

Scoping Linc Tape Timing

OBJECTIVE:

To introduce the student to procedure by which
he may determine Linc Tape failures.

PROCEDURE:

Using an oscilloscope, observe the waveform at
pin D2, G882 (read amplifier) in slot F05.
Compare the above waveform to the waveform at
Pin U2.
Note that there is an output from the amplifier
with no tape.motion.
Deposit at Loe. 4020

/0702
/7000
/0702
/7777
/6020

Before running the program, decide what it should
do.
Run the program.

Make a timing chart which reflects the following
signals:
1 • LTR Head T H
2.

LTR T Read H

LTT Read ¢ L

LTT TP¢ H

LTT TPl H

LTT TP2 H

L'I'I' TP3 H

LTT TP4 H

Go to Job Sheet #10-2

PDP-12 LAB JOB SHEET //10-2

TITLE:

Scoping the Mark Track

OBJECTIVE:

PROCEDURE:

Using an oscilloscope, observe the data into
the window (LWN Wind data IN L)

give the student confidence in his ability
to successfully scope the Mark track decoding.

Sync on LWN DM H
Observe the Data Mark code being shifted into
the window.

PDP-12 LAB #11

TIME:

2 hours .
1.

Tape Delay Adjustments

Troubleshooting the TC-12

OUTLINE

PDP-12 LAB JOB SHEET ffll-1

TITLE:

TC-12 Tape Delay Adjustments

OBJECTIVE:

To familiarize the student with the adjustments
of the TC-12 delays and the problems that occur
from maladjusted delays.

PROCEDURE:

Using the procedure described in the PDP-12
Maintenance Manual, Volume 2, perform the
following adjustments:

3.5.1

Tape timing pulses

3.5.2

LTD XTLK Delay

3.5.3

LTD TTOK Delay

3.5.4

LTD TAPE FAIL Delay

3.5.5

LTD ACIP Delay .

3.5.6

Mark Clock Adjustment

PDP-12

TIME:

LAB #12

2 Hours

Use of Tape Diagnostics

TC-12 Troubleshooting

OUTLINE

PDP-12 LAB JOB SHEET #12-1
TITLE:

Use of Tape Diagnostics

OBJECTIVE:

To ensure that all students understand the
procedure for running ta ·: diagnostics

PROCEDURE:

Using a PDP-12 maintenan~e tape or paper
tapes, load and.· run the following Maindecs:
Tape Quickie

TC 12-I
TC 12-II
Tape Data
Any failures should be corrected at this time·.

PDP-12 LAB //13

TIME:

2 Hours

Calibration of AD-12

Troubleshooting AD-12

OUTLINE

PDP-12 LAB JOB SHEET # 13-1

TITLE:

Calibration of AD-12

OBJECTIVE:

To ensure that all students understand and can
perform the calibration of the AD-12.

PROCEDURE:

Perform the adjustments described in the PDP-12
Maintenance Manual, Volume 2, section 3.8.5--

3.9.2 .

PDP-12 LAB #14

TIME:

2 Hours

VR-12 adjustments

VR-14 adjustments

Troubleshooting the VC-12

OUTLINE

PDP-12 LAB JOB SHEET #14-1

TITLE:

VR-12 Adjustments

OBJECTIVE:

To ensure that all students are capable of
correctly adjusting the VR-12 display.

PROCEDURE:

Does your PDP-12 system contain a VR-12 or
a·vR-14?
VR-12: Use Job Sheet #14-1. Upon completion,
go to a system which contains a VR-14 and use
Job Sheet #14-2.
VR-14: Use Job Sheet #14-2. Upon completion,
go to a system which contains a VR-12 and use
Job Sheet #14-1.
Perform the adjustments described in the PDP-12
Maintenance Manual, Volume 2, section 3.8
through 3.8.4 •

PDP-12 LAB JOB SHEET #14-2

TITLE:

VR-14 Adjustments

OBJECTIVE:

To ensure that all students are capable of
correctly adjusting the VR-14 display.

PROCEDURE:

Does your PDP-12 system contain a VR-12 or
a VR-14?
VR-12: Use Job Sheet #14~1. Upon completion,
go to a system which contains a VR-14 and use
Job Sheet #14-2.
VR-14: Use Job Sheet #14-2. Upon completion
go to a system which contains a VR-12 and use
Job Sheet #14-1.
Perform the adjustments described in the PDP-12
Maintenance Manual, Volume 2, section 3.8
through 3.8.4 •

PDP-12 LAB #15

TIME:

2 Hours.

KW-12A

Diagnostic usage

KW-12A

Troubleshooting

OUTLINE

PDP-12 LAB JOB SHEET #15-1

TITLE:

~~-12A

Diagnostic

OBJECTIVE:

To ensure that all students can successfully
run the KW-12A diagnostic and understand any
failures which the diagnostic should indicate.

PROCEDURE:

Load and run the KW-12A diagnostic. If
failures occur, -obtain the appropriate writeup and correct the problem.

PDP-12 LAB JOB SHEET //15-1

TITLE:

K~-12A

Diagnostic

OBJ~CTIVE:

To ensure that all students can successfully
run the KW-12A diagnostic and understand any
failures which the diagnostic should indicate.

PROCEDURE:

Load and run the KW-12A diagnostic. If
failures occur, . obtain the appropriate writeup and correct the problem.

PDP-12 LAB }16

OUTLINE

PDP-12/10 System Troubleshooting

PDP-12/20 System Troubleshooting

PDP-12/30 System Troubleshooting

.4.

PDP-12/40 System Troubleshooting

PDP-12 LAB JOB SHEET #16-1, 2, 3, 4

To be Supplied