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EK-0TU81-PS-002

August 1954

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Document:	TU81 Magnetic Tape Subsystem Pocket Service Guide
Order Number:	EK-0TU81-PS
Revision:	002
Pages:	144
Original Filename:

OCR Text

EK-0TU81-PS-002

Issued by

(UK) LIMITED

Training Department

FOR REFERENCE ONLY

NOT MAINTAINED

TU81 Magnetic
Tape Subsystem
Pocket Service Guide

Prepared by Educational Services
of
Digital Equipment Corporation

1st Edition, August 1984
2nd Edition, May 1986

The reproduction of this material, in part or whole, is strictly
prohibited. For copy information, contact the Educational
Services Department, Digital Equipment Corporation,
Maynard, Massachusetts

01754.

The information in this document is subject to change
without notice. Digital Equipment Corporation assumes no
responsibility for any errors that may appear in this document.
LEGAL NOTICE

TMSCP and STI protocols and documentation are the proprietary information of Digital Equipment Corporation.
UNIBUS/Q-BUS/BI-BUS port drivers and documentation
for MSCP/TMSCP products are also proprietary information of Digital Equipment Corporation.
The following are trademarks of Digital Equipment Corporation, Maynard, Massachusetts.

ol oliltlali

DECwriter RSTS

DECmate

MASSBUS

DECnet
DECsystem-10
DECSYSTEM-20
DECUS

PDP
VAX
P/OS
VMS
Professional VT
Rainbow
Work Processor

DEC

DIBOL

RSX

UNIBUS

CONTENTS

PREFACE
1

INTRODUCTION

1.1

General

1.2

Subsystem Overview

1.3

TUS81 Configuration

1.3.1

Power Supply

1.3.2

Pressure Pump Shutdown

1.4

Spares Kit

1.5

Tools

1.6

Documentation

1.7

Control Panel

1.7.1

Operator Controls

1.7.2

Diagnostic Controls

1.7.3

Special Controls

1.7.4

Diagnostic/Maintenance Panel

1.7.5

Unit Number

Operation
1.7.6
1.8

ASCII Port Diagnostics

Maintenance

1.8.1

Removing Shipping and Safety
Brackets

1.8.2

Quick Disconnect Tabs

1.8.3

Top Cover Interlock Switch Defeat

1.9
2

ooooooooo

Subsystem Diagnostics
INSTALLATION

2.1

Interblock Gap Configuration Setting

2.2

TU81-to-Host Interfacing

22
22

2.2.1

TUS81-to-Host External Cabling .......

222

UNIBUS Adapter Module

----------

Installation and Replacement .........
223
2.3

Installing the I/O Bulkhead Frame
Baud Rate Selection

oooooooooo

CONTENTS

TROUBLESHOOTING
General
Resident Diagnostics

3.1
3.2

3.2.1
3.2.2
3.2.3

324

3.2.5

3.2.6
3.3
3.3.1
3.3.2

36
36

Corrective Fault Code Matrix
Operator Troubleshooting
Power-On Health Check
Operator/Field Service Diagnostic

37
37
42

Test 01

Tape Sticking Problem
Field Service Diagnostic Listing ...............

45
45

VAX-Executable Diagnostics
M8739 Status Checking
VAX Front-End Diagnostic

45
45

(EVMBB)

3.3.3

VAX Data Reliability Diagnostic
(EVMBA)

3.34

Basic Operating Instructions for

VAX-Based Diagnostics

3.3.5

System Exerciser

3.3.6

EVMBB Sample Error Printout ................

PDP-11-Executable Diagnostics
34.1

34.2
343
344
3.5

3.5.1
3.5.2
3.5.3
3.54

3.6
3.7

Operating Instructions for PDP-11-Based
Diagnostics
51

CZTU2 Front End Functional
Diagnostic
CZTU1 Data Reliability Test
CXTUCA DEC/X11 Module
ASCII Port Diagnostics
Port Access
Diagnostic Commands
Message Format
Special Diagnostic Test 27
Maintenance Indicators and Fault/
Error Codes
Operating System Error Log Decoding
and Troubleshooting

52
52
53
53
56
58
58

59
61
64

REMOVAL AND REPLACEMENT
Access to Tape Deck Components .................

Protective Drive Cover
Tape Cleaner Assembly

74
75

Top Cover Interlock Switch

File Protect Sensor

EOT/BOT Sensor Assembly
Take-Up Reel Hub Assembly

79
80

- Take-Up Reel Motor Assembly

Supply Reel Hub Assembly

CONTENTS

4.10

Supply Reel Motor Assembly

4.11

Supply Motor Tachometer and Sensor .........

4.12

Air Bearing Sensors

4.13

Air Bearing Spring Guides

4.14

Pneumatic Pump Assembly

4.15

Pressure Regulator and Filter

Assembly

4.16

Magnetic Head Assembly

4.17

Control Panel Assembly

4.18

Cooling Fan Assembly

4.19

Power Supply

100

4.20

Write Driver Module

104

421

Read Amplifier Module

108

4.22

Servo Control Module

112

423

Formatter Read Module

114

4.24

Formatter Write Module

116

4.25

TMSCP Interface Controller

Module

118

4.26

Power Amplifier Module

120

4.27

Capacitor Assembly

122

APPENDIX A

SENSE BYTES

APPENDIX
B

TROUBLESHOOTING
FLOWCHART

APPENDIX C

MALFUNCTION MATRIX

APPENDIX D

INSTALLING ADDITIONAL

UNIBUS ADAPTERS (M8739)

TU8I Cabling Diagram

1-2

TU81 Block Diagram

1-3

Logic Module Locations

1-4

Maximum TUS81 Configuration

1-5

TUS81 Tape Subsystem

1-6

Tape Deck

1-7

874 Power Controller

1-8

Control Panel

1-9

Shipping and Holding Bracket
Removal

1-10

Quick Cable Disconnect Tabs

1-11

Cover Interlock Defeat Tool

2-1

Formatter Write Module

2-2

Interface Cabling

2-3

Cable Connections

N CO~ION
i BN

1-1

[

FIGURES

CONTENTS

2-4

External I/O Cable Connection to the
Logic Cage

2-5A

M8739 UNIBUS Adapter Module

(Style A)
2-5B

M&739 UNIBUS Adapter Module

2-6

UNIBUS Address Selection Diagram

2-7

Bus Grant Continuity Card

2-8

NPG Jumper

(Style B)

2-9

SPC Module Installation

2-10

I/O Cable Installation on the CPU

ooooooooooo

Bulkhead

2-11

Baud Rate Selection

3-1

Power-On Health Check Flowchart ...

3-2

ASCII Port and EIA Cable

3-3

Error/Status Code Word Format

4-1

TUS81 Maintenance Access

4-2

Tape Deck Layout

4-4

Tape Cleaner Assembly

4-5

Top Cover Interlock Switch

4-6

File Protect Sensor Alignment

-----------

Protective Drive Cover

4-7

EOT/BOT Sensor Assembly

4-8

Take-Up Reel and Supply Reel Hub

Assemblies
4-9

Take-Up Reel Motor Assembly

4-10

Supply Reel Motor Assembly

4-11

Tachometer Wheel and Sensor

4-12

Air Bearing Sensors

Alignment

4-13

Air Bearing Spring Guide

4-14

Pneumatic Pump Assembly

4-15

Filter Box Assembly

4-16

Magnetic Head Assembly

4-17

Control Panel Assembly

4-18

Cooling Fan Assembly

4-19

Power Supply

4-20

Power Supply (Rear Cabinet View) ................

4-21

Voltage Select Card

4-22

Power Terminal Strip TB1

4-23

Logic Cage for Write Driver, Read
Amplifier, and Servo Control Modules

4-24

Write Driver Module

4-25

Read Amplifier Module

4-26

Removing Write Driver, Read
Amplifier, and Servo Control Modules

4-27

oooooooo

Servo Control Module

--------

CONTENTS

4-28

vii

Logic Cage for Formatter Read, Formatter

Write, and Interface Modules

115

4-29

Formatter Write Module

117

4-30

TMSCP Interface Controller Module ........... 119

4-31

Power Amplifier Module

121

4-32

Capacitor Assembly

122

B-1

Troubleshooting Flowchart

129

TABLES

1-1

Recommended Spares List (RSL) ..................

1-2

Related Documents

Document /PN

Description

TU81/TA81 Subsystem
User Guide
(EK-TUAS81-UG)

Contains a functional overview and

TU81/TA81 Technical/

Service Manual

Contains a system functional
description, installation and accept-

(EK-TUA81-TM)

ance procedures, theory of opera-

installation, operating, and programming information.

tion, and maintenance information.
TU81/TA81 Pathfinder

Contains detailed troubleshooting

(EK-TUA81-SV)

information including troubleshooting procedures, tests, and subfault
codes.

TU81/TA81 Illustrated
Parts Breakdown

Provides a list and illustrations of
replaceable parts.

(EK-TUARI1-IP)
874 Power Controller

Provides a list and illustrations of

Illustrated Parts Break-

replaceable parts.

down (EK-00874-1P)
TUR1 Field Maintenance

Provides unit assembly (UA) draw-

Print Set (MP-01618)

ings and interconnect schematics.

INTRODUCTION

1.7

CONTROL PANEL

The following paragraphs discuss the control panel, diagnostic/maintenance panel operation, and on-line system
diagnostics.

Figure 1-8 shows the control panel of the TU81 tape

transport.

All panel switches are pushbutton type. These switches
and their corresponding functions are discussed below.
The central part of the control panel (operator) contains
the operator switches and indicators. The three-digit display shows the unit number during normal operation. If an
error occurs, during on-line operation or off-line diagnostic
routine, the display indicates the three-character fault
code (for example, E31). While the off-line resident diagnostic is running, the display shows the number of the test
in progress.

The right part of the control panel (maintenance) contains the switches and indicators for running the resident
diagnostic test routines.

The left part of the control panel (special) contains
special purpose switches, connectors, and indicators. These
are the FAULT/CONTROLLER switch/indicator and
the ASCII test panel used by Field Service.
MAINTENANCE

SPECIAL

—

[5)
FILE PRO

TERM /O

O LOGIC

LOAD

REWIND

OFF

UNLOAD

1AMP POWER
|S

)

O HIGH
DENSITY

[e)
BOT

LINE

RESE

T | oispLay

/Ve

DIAGNOSTICS

TEST

STEP

EXECUTE

THREE-DIGIT

R——

OPERATOR

INDICATOR

PUSHBUTTON
MA-1161-83

Figure 1-8

Control Panel

INTRODUCTION

1.7.1

Operator Controls

The following chart describes the operator controls.
Switch/Indicator

Function

LOGIC OFF

Indicator - When on, indicates a
power fault condition, that is, a fail-

ure in the transport’s power supply
operation.
LOGIC ON

Indicator — When on, indicates a

normal power-on condition with all
dc voltages applied to the transport’s control system and circuits.
NOTE
The LOGIC OFF and LOGIC ON pushbuttons do
not operate.

FILE PRO

Indicator — When on, indicates that
there i1s no write enable ring in the
supply reel and write operation is
inhibited. Otherwise, write operations are allowed.

BOT

Indicator - When on, indicates that
the tape is loaded and positioned at
the beginning-of-tape (BOT)
marker.

LOAD/REWIND

Switch - If the transport is powered
on and the tape is threaded, pressing
this switch causes a load operation
to be performed. If the tape is
already loaded, pressing the switch
causes a rewind operation to BOT.

UNLOAD

Switch — If the tape is loaded at
BOT, pressing this switch causes the
tape to unload from the take-up reel

and tape path onto the supply reel.
If the tape is loaded beyond BOT, it

rewinds to BOT and unloads the
tape. If the tape is threaded but not
loaded, pressing the switch causes
the transport to slowly unload the
tape onto the supply reel.

INTRODUCTION

Switch/Indicator

Function

ON-LINE

Switch — If the tape is loaded, pressing this switch causes the transport
to become available to the host system. Press the RESET switch to
take the TUS81 off-line.

Indicator — When on, ON-LINE
indicates that the TUS81 is ready for
on-line operation. All switches
except RESET are inhibited.
HIGH DENSITY

Indicator — When on, indicates that
the transport is selected by the host
system for GCR operation.

FAULT/RESET

Indicator - When on, indicates that
the transport is in fault or diagnostic
status. The three-digit display may
contain a fault or diagnostic code.

RESET

Switch - When pressed, the
RESET switch places the transport
off-line, stops tape motion, and
clears error status. The switch can
stop a LOAD or REWIND operation. It also turns off the
FAULT/RESET indicator and
clears the diagnostic test condition.

1.7.2 Diagnostic Controls
The following chart ldescribes the diagnostic controls.
Switch/Indicator

Function

DIAGNOSTIC

Indicator - When on, indicates that
the transport is in the diagnostic/test mode. The indicator
remains on until you press the
RESET switch.

TEST

Switch - If the transport is not online and/or the tape is threaded but
not loaded, pressing this switch

places the unit in the diagnostic/test
mode. It is also used as an X10 multiplier in the diagnostic mode.

INTRODUCTION

Switch/Indicator

Function

STEP

Switch — If the transport is in the

diagnostic/test mode (and the test
number is displayed), pressing this
switch allows the diagnostic/test
sequence numbers in the three-digit
display to increment by one to a
required digit.
EXECUTE

Switch — If the transport is in the

diagnostic/test mode (and the test
number is displayed), pressing this
switch initiates the internal diagnostic test shown in the three-digit
display.

Switch — If the transport is in the

diagnostic/test mode, the CE (customer engineer) switch helps to
recall and run Field Service diagnostics. Press CE and TEST simultaneously to put the transport in resident
diagnostic mode.
1.7.3

Special Controls

The following chart describes the special purpose controls.
Switch/Indicator
CONTR FAULT

Function

Indicator — When on, indicates the

TMSCP interface controller fault
condition until the condition is
cleared by the TU81 or the host.
Switch

With

the

CONTR

FAULT indicator on, pressing this
switch causes the TU81 transport to
attempt to clear the fault condition.

If the fault is corrected (through
either the transport or the host), the
CONTR FAULT indicator goes off
and the TUS81 is available to the
host again.

INTRODUCTION

1.7.4 Diagnostic/Maintenance Panel Operation
The TUS81 has internal (resident) diagnostics that can be
initiated through the transport’s control panel. The internal diagnostics include an operator diagnostic test (test O1)
and a set of Field Service diagnostic tests (customer engineer tests), described in Chapter 3.
To get into diagnostic mode and initiate operator or
Field Service diagnostic tests, use the diagnostic panel as
follows.

1. To recall operator diagnostic test Ol, press TEST.
The number 01 will appear on the three-digit display.
If you need test 02 or 03, use STEP. Each time you
press STEP, the display number increments by one.
Press EXECUTE to initiate the test you want.
2. To recall Field Service resident diagnostics, press and
hold CE and press TEST.

a. The DIAGNOSTICS indicator lights.
b. The number 00 appears on the three-digit display.
c. Press STEP.

The display number increments by one each time
you press STEP, or increments automatically if
you press and hold STEP. The display can show
00 through 09.

d. To select a test number, use the STEP and TEST
switches. When you press TEST after you press
STEP, the number is multiplied by 10.
Example: Test 39 is required.
Step

Display

1. Press CE and TEST.

2. Press STEP three times.

3. Press TEST.

4. Press STEP until 9 is

displayed.

e. Press EXECUTE to initiate the test.-

After the fault code appears on the display, you can
recall the subfault code by pressing CE. The subfault code
is displayed as long as you hold CE.

INTRODUCTION

1.7.5 Unit Number
The unit number is a number from 0 to 255. It is used as a

unit address feature giving each tape transport a unique
code to be recognized by the host. This number is especial-

ly useful for system error logging and in multidrive con-

figurations, because it enables you to re-address your
peripheral device from one drive to another in case of tape

drive failure, connection breakdown, and so on.

The unit number is a three-digit code that is manually
entered from the transport’s control panel using procedure

04 shown below. This unit number is stored in the transport’s nonvolatile memory (that retains stored data in case

of any power fluctuations or failure) until you enter a new

unit number. The unit number is continuously indicated

on the transport’s display when the drive is powered on
and is in its normal on-line, off-line, or tape-unloaded
status. Only when there is a fault condition, or the diagnostic test is run from the control panel, is the unit number
replaced by the fault code or test number.

To enter the unit number, use procedure 04.

Example: To enter unit number 201, proceed as follows.
Step
1. Press TEST.

Display
|

DIAGNOSTICS
,

indicator on

01
2. Press STEP three times.

3. Press EXECUTE to initiate

000

procedure 04.

4. Press STEP twice.

002

5. Press TEST twice.

200

6. Press STEP once.

201

7. Press EXECUTE.

8. Press RESET.

201

1.7.6 ASCII Port Diagnostics
These diagnostics are run using any RS232-compatible
terminal (including Digital’s hand-held terminal) plugged
into the ASCII signal port on the TU81’s control panel.

Refer to Paragraph 3.4 for detailed information.

INTRODUCTION

1.8

MAINTENANCE

NOTE
The TU81 does not need any mechanical and/or
electrical adjustments or alignments for corrective or preventive maintenance.

The only maintenance required is regular cleaning of the

tape path components. Also, the TU81 has several safety
features as described below.
1.8.1
Removing Shipping and Safety Brackets
The TUS81 has three sets of shipping and safety brackets

that are used to secure the tape deck and PC boards
during shipment. The front bar and rear bracket are
removed when the transport is installed at the user’s site
(refer to Chapter 5, Mechanical Installation, in the
TU81/TA81 Subsystem User Guide).
The shipping and safety brackets on the logic cage must
be removed and the retaining latch released from the shipping position when any of the PC boards are replaced. For
additional information on board replacement, refer to Paragraph 4.20. Proceed as follows (Figure 1-9).
1.

With the tape deck in the maintenance (vertical) position (Paragraph 4.1), loosen the mounting screws and
remove the lower shipping bracket from the logic
cage.

Using a screwdriver, pull the retaining latch from the

shipping position to the operating (middle) position.
3.

On the top of the logic cage, release the mounting nut

and remove the holding (safety) bracket.
NOTE
This bracket may be put back when the PC
board has been replaced.

Store all the brackets for future reshipments.

INTRODUCTION

SCREWDRIVER
=7

HOLDING

BRACKET

SHIPPING

BRACKET

MA-0357-84

Figure 1-9

Shipping and Holding Bracket Removal

INTRODUCTION

1.8.2

Quick Disconnect Tabs

Most of the cable connectors in the drive have “quick
disconnect tabs” to make cable connection quick and safe.

//MWWM )

TABS OPEN

YOV
eO
WYL

Figure 1-10 shows how the tabs work.

00000077.

ilg/

TABS CLOSED j

MA-0412-84

Figure 1-10

Quick Cable Disconnect Tabs

INTRODUCTION

1.8.3 Top Cover Interlock Switch Defeat
.
When servicing the TUS81, you may have to operate the
unit and run diagnostic tests with the top cover open. To
bypass the safety interlock switch, use the interlock defeat
tool supplied in the TU81 CD kit. Insert this tool into the
interlock latch and turn it 90 degrees to keep it locked in

the latch cutouts. This keeps the interlock switch
depressed, simulating the top cover closed condition (Figure 1-11).
1.9

SUBSYSTEM DIAGNOSTICS

The TUS8I1 is used with VAX or PDP-11 systems. You can
use on-line and off-line host diagnostics to check and
troubleshoot the TU81 subsystem. Paragraphs 3.3 and 3.4

describe these tests.

INTERLOCK
LATCH
DEFEAT

TOOL (////

MA-0076-83

Figure 1-11

Cover Interlock Defeat Tool

2 INSTALLATION
This chapter provides information on how to select and
check the transport configuration (transport addresses and
options), and install or replace the M8739 UNIBUS/lowend storage interconnect (LESI) adapter module.

2.1

INTERBLOCK GAP CONFIGURATION
SETTING
During transport repair, check the transport’s formatter
write (FW) module for correct setting of the transport
interblock gap (IBG) selection jumper W1.
Table 2-1 and Figure 2-1 identify this feature and the
jumper location on the FW module.
NOTE

This is the standard, factory-set jumper setting,
used for normal operation.
2.2 TU81-TO-HOST INTERFACING
The TUS8I tape transport communicates with the host via
the UNIBUS LESI interface, which consists of the LESI
I/O cables and the M8739 LESI module. The M8739 is a
standard quad-height double-length PC card that plugs
into any small peripheral controller (SPC) slot of the host
computer backplane. The module contains a switchpack
and jumper for setting the desired I/O address. The interrupt vector cannot be set by the hardware, but is set by the
host software.

The M8739 is connected to the TU81 tape transport by
a set of I/O cables. The interface cable connections are
shown in Figures 2-2 through 2-4.

Table 2-1

Interblock Gap Setting

Function

Jumper /Switch

Variable long gap
(0.6 to 1.2 in)

W1 positions 1 and 2

INSTALLATION

FORMATTER
READ

MODULE

’

[

r
X

N
3

W7P8

.
J1

321

S
N
N

]
W1

3
N
§

FORMATTER

WRITE

MODULE

Figure 2-1

Formatter Write Module

MA -0555-84

INSTALLATION

)
/0

INTERNAL

CABL.E(70-19923)
UNIBUS

ADAPTER
MODULE
LCGIC RA

(M8739)
CcPU
BULKHEAD
PANELS AND

CONNECTORS

EXTERNAL
INTERFACE

CABLE (BC17Y-20)

MA-1170-83

Figure 2-2 Interface ’Cabling

SHIELDED
[hosTcPu —l
I

FEMALE

(ROUND)

FAPE TRANSPORT
l

INTERFACE

CABLE

TMSCP

M8739 [

CONTROLLER

MODULE
1/0

PANELl

L —_———

MALE

FORMATTER

MODULE

MALE

e e ———

(1) FLAT CABLE (IN CPU) (70-19923)
@ EXTERNAL SHIELDED CABLE (BC17Y-20)
MA.1172-83

Figure 2-3

Cable Connections

INSTALLATION

FLAT 1/0 CABLE
IN LOGIC CAGE

I/0 CABLE

MA-1174-83A

Figure 2-4

External I/O Cable Connection to the
Logic Cage

2.2.1

TUS81-to-Host External Cabling

Use the following procedure to connect the host to the
TUSI.

1. On the TU81, open the rear door and free the external I/O cable (PN BC17Y-20). The TU81 is shipped
with this cable plugged in and secured in the socket
on the logic cage panel (Figure 2-4). The flat ribbon
cable connects the external I/O cable to the TMSCP
interface controller module inside the logic cage.
NOTE

Verify proper connection of both I/0 cables.
Check for loose connections, loose mounting
screws, and dangling cables or wires. To do this,
tilt the tape deck into the maintenance position
as described in Paragraph 4.1.

2. Insert and secure the other plug of the external I/O
- cable (PN BC17Y-20) in the designated connector on
the CPU 1/0 bulkhead as shown in Figure 2-2. Refer
to Paragraph 2.2.4 on how to properly install the I/O
frame or panel on the CPU rack.

INSTALLATION

2.2.2 UNIBUS Adapter Module Installation and

Replacement
When you have to install the M8739 in the CPU (during

subsystem installation or module replacement), the proce-

dure includes: preparing the M8739 (address switch
checking or setting), installing the M8739 in the SPC slot,
and interface cabling. Refer to the following paragraphs
and figures for the required procedures.

NOTE
The following procedures must be performed by
a qualified Field Service technician. Use the
(TU81K-CP) and accessory kit

CPU kit

(TU81K-AC) in this procedure.

1. Remove the M8739 module, ribbon I/0 cable, CPU

bulkhead connector panels, and mounting hardware

from the TU81K-CP shipping container. Unwrap and
examine them for any physical damage.
2. On the M8739 module, select the proper UNIBUS

address using a single 10-position DIP switchpack
(location E44) and jumper W2 (location E68). Refer
to Figures 2-5 and 2-6 and Tables 2-2 and 2-3 for the
address settings.

NOTES
1. If this is the first TU81 on the host CPU,
check the DIP switchpack and the jumper,
to make sure that the module is set for

address 774500(8).

‘2. The typical UNIBUS address and vector for

a single TU81 subsystem configuration are
specified in Table 2-2.

On VAX systems when more than one (up to
four) TU81s are installed, the UNIBUS
addresses are selected using the SYSGEN
procedure.

Refer

Table

2-3

for

example.

On PDP-11 systems when more than one (up
to four) TU81s are installed, follow the procedure described in Appendix D to select
UNIBUS addresses.

INSTALLATION

. Use the address setting diagram (Figure 2-6) to set
the UNIBUS address. The M8739 will only recognize
two UNIBUS addresses: for the interrupt priority
(IP) and status address (SA) registers. The base
address (IP register) is 774XXX. The status address
(SA register) is 774XXX +2. The interrupt vector is
set by system software.

. Set the switches on the 10-position DIP switchpack

according to the diagram. Address bits 12 through 3
are specified by the DIP switch. Address bits 17
through 13 are hardwired to be 1s. Address bit 2 is
set by the W2 jumper (Figure 2-6). Address bits 1
and O are ignored.

. Plug the ribbon I/O cable (PN 70-19923) into edge
connector J1 on the M8739 module (Figure 2-5).
. Turn off power to the CPU.

4
FLAT I/0 CABLE

“\“

(D /

»
'

)

REFERENCE EDGE

=
i

““

ke
\‘}'

LS
“,‘A

“

5
“

,\‘\“

"‘-‘

o
=~

|
JUMPER
P

‘

;f;(j’

//
>

.%g)
AR )1
3»”

NOTE:

NOTICE THE POSITION OF ARROWS ON

CABLE CONNECTOR AND J1 CONNECTOR.
W2

FOR A02=0, W2=A
&B
FOR AD2=1, W2=B&C

Figure 2-5A

M&739 UNIBUS Adapter Module (Style A)

INSTALLATION

FLAT I/O CABLE
PN 70-19923
L

w O
w 0
o W

CSR ADDRESS DIP SWITCHPACK

N N

’ % g K = iy - A r o\
A

MPER

50
° &

[PEE——}

t 09

e
k2
©

FOR AO02
FOR A02

0. W2

1 W2

A&B
B&C
MA-1166-83

SHR-0171-85

Figure 2-5B

M8739 UNIBUS Adapter Module (Style B)

weIfelq UonodRS sSAIPPY SNAINN 9-T 2In31g

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29
INSTALLATION

INSTALLATION

Table 2-2

Single-TU81 Address Selection

Unit

Number

Address

Vector

7745004

260g

F9401¢

BOj¢

Table 2-3 Address Selection in Multi-TU81 Configuration

Unit
Transport

Number Address

2t04

Vector

Configuration

7745008

260g

1 (unit 0)

F940,¢

B01g

CSR

Vector

range

range*

760000-

300-

717774 ¢

700 g

2 to 4 (units 1 to 3)

Example:

For TU81 subsytem(s) installed on a VAX system, use the following SYSGEN procedure to find the available CSR addresses
and vectors. Then select the CSR address on the UNIBUS DIP

switchpack (Figures 2-5 and 2-6).

MCR

SYSGEN

SYSGEN>CONFIG
DEVICE>RKG6
11

DEVICE>DZ11
DEVICE>TU81,

DEVICE>nZ

DEVICE:TK611

NAME:DMA

CSR:777400

VECTOR:210

DEVICE:TU81

NAME:PTA

CSR:774500

VECTOR:260

DEVICE:DZ211

NAME:TTA

CSR:760100

VECTOR:300

DEVICE:TU81

NAME:PTB

CSR:760444

VECTOR:310

DEVICE:TU81

NAME:PTC

CSR:760450

VECTOR:314

SYSGEN>nZ
$

Appendix D describes the procedure to find CSR addresses for

TUS81 subsystem(s) installed on PDP-11 systems.
* The vector is set automatically in the range from 300 to

700(g) by the system software.

INSTALLATION

7. On the CPU backplane, remove the G727 bus grant
card from the desired SPC slot (Figure 2-7). A bus

grant (continuity) card must be in connector D of any
unused SPC slot. Otherwise, bus grant continuity will

be lost.
8. Also in the same SPC slot, remove the nonprocessor

grant (NPG) jumper (CA1 to CB1) on the pin side of
the backplane (Figure 2-8).
9.

Carefully insert the M8739 module into the SPC slot,
as shown in Figure 2-9.
WARNING

Make sure that the module is installed in backplane
connector rows C, D, E, and F. Installing the module

in any other connector rows will damage the module.

NOTE
Examine the CPU for compliance with the FCC
installation specifications. To meet these requirements, the CPU should have the 1/0 bulkhead con-

nector frame. If this frame is not installed, refer to
Paragraph

2.2.4,

Installing

the

I/0O

Bulkhead

Frame.
10.

Install and secure the 1/O panel (PN 74-26407-13)
on the CPU’s bulkhead frame at the bottom of the

CPU cabinet (Figures 2-2 and 2-10).

G727 {SHOWN) OR G7270,
BG CONTINUITY, CARD
INSTALLS INTO CONNECTOR D

OF ANY UNUSED SPC SLOT.

)

NOTE

IF G7272 1S INSTALLED, 1T FITS

INTO SLOTS C AND D.

Figure 2-7

Bus Grant Continuity Card

MA.B78S

INSTALLATION

-oTM £s8%

BN B\

....

ozl

Figure 2-8

NPG Jumper

FRONT

Figure 2-9

SPC Module Installation

INSTALLATION

11. Route the ribbon /O cable from the M8739 through
the CPU cabinet down to the I/O frame and insert
the cable connector (female) into the 1/O panel slot
(PN 74-26407-13). (Secure the connector with the
two 4/40 hex standoffs provided.)
NOTE
Be careful not to chafe the ribbon I/0 cable
against other PC cards and chassis parts.

12.

Insert the free plug of the external shielded 1/O cable

from the TUS81 into the I/O slot connecting both I/O
cables. Secure the connection with two screws (Figure

2-10).
13. Power up the CPU and proceed with system initial-

ization and TU81 acceptance testing.

2.2.3
1.

Installing the I/O Bulkhead Frame
Mount the I/O panel (PN 74-26407-13) on the 1/O
frame (PN 74-27292-01) and secure it with two
screws (Figure 2-10).

Install the I/O frame (with the I/O panel) on the
CPU rack. Find the best location on the CPU rack to

accommodate internal and external cables.

NOTE
The recomimended location for the I/0 frame is
at the bottom rear of the CPU cabinet.
2.3

BAUD RATE SELECTION

The data transfer rate is factory set at 300 baud by
jumpers W2 and W3 at J6 on the TMSCP interface module (Figure 2-11). If necessary, you can change the baud
rate for transmit and receive in the range from 300 to

9600 baud. Use the W2 jumper for setting the transmit
rate and the W3 jumper for setting the receive rate.

INSTALLATION

HEX

STANDOFF

/
I/0 FRAME

74-27292-01

P
2
é

I/0 PANEL
74-26407-13

CPU REAR

MA-1171-83

Figure 2-10

I/O Cable Installation on the CPU Bulkhead

INSTALLATION

48 = 4800 BAUD

96 = 9600 BAUD
3= 300 BAUD
12 =1200 BAUD

MA-0358-84

Figure 2-11

Baud Rate Selection

3 TROUBLESHOOTING
3.1

GENERAL

The troubleshooting flowchart (Appendix B) and the malfunction matrix (Appendix C) show the path you should
follow when troubleshooting the TU81. Paragraph 3.2
describes the internal (resident) diagnostics; Paragraph 3.3
describes the VAX-executable diagnostics; Paragraph 3.4
describes the PDP-11-executable diagnostics; and Paragraph 3.5 provides basic information on the ASCII port
usage and available diagnostics. Paragraph 3.6 describes
the TU81 maintenance indicators and error codes, and
Paragraph 3.7 describes the troubleshooting information
provided by the operating system error log.

When you report to the site, get all the available information from the operator and operating system. You
should consider fault codes, including the frequency at
which they occur, and, if possible, the operation in progress at the time the fault occurred before you execute
diagnostics. If the fault is intermittent, information from
the operator and operating system may help direct you to
the appropriate test to duplicate the fault condition.
3.2

RESIDENT DIAGNOSTICS

TUSI resident diagnostics consist of operator diagnostics
and Field Service diagnostics.
NOTE

Make sure that the TU81 power cord is plugged
in and the power switch is on before you start
any diagnostic routine.

The diagnostic tests designed into the TU81 are off-line
tests initiated through the control panel. There are no
‘built-in on-line diagnostics; however, the host CPU can
monitor TU81 status through the GET STATUS command. A CHANNEL LOOPBACK command is also provided to test the TU81’s formatter logic.
Although host-controlled diagnostics are not part of the
TUS81, the control microprocessor tests for many opera-

tional fault conditions while it runs on-line. These conditions are indicated on the control panel display as fault

TROUBLESHOOTING

codes. The FAULT/RESET indicator lights to indicate
the transport fault condition, and the control panel displays the appropriate fault code.

The CONTR/FAULT indicator comes on when the
TMSCP controller or the M8739 UNIBUS/Q-Bus adapter module fails.
3.2.1

Corrective Fault Code Matrix

When a trouble call is received from the site, you should
consult the fault code matrix (Table 3-1) and the malfunction matrix (Appendix C) as well as the fault and subfault
code listings and corresponding corrective action tables in
the

TUS81/TA81

Pathfinder (EK-TUAS81-SV). These

tables will help you determine if operator action (A, B, or

C) 1s required. If the fault persists after appropriate operator action, consult the tables for a list of FRUs to take to
the site.
Test 01 (Paragraph 3.2.4) is a lead-on for all other tests.
The fault code matrix (Table 3-1) lists all malfunctions or
fault codes, and assemblies that may cause the fault condition. This table is designed to provide a list of related

assemblies before you report to the customer site. Assemblies listed under individual malfunction or fault codes are
arranged in a “most probable fault” order.
When you are on-site, refer to the TU81/TA81 Pathfinder (EK-TUA81-SV) (troubleshooting procedures and

diagnostic tests) to isolate and correct the malfunction.
3.2.2

Operator Troubleshooting

Before you run any tests, perform the following steps to
isolate an easily correctable external malfunction.
1.

Make sure the tape has a BOT marker.

If a write operation is to be performed, make sure the

tape reel has the write enable ring installed.
3.

Make sure the tape path is clean.

Make sure the power switch is on (1).

Incase of a power failure, make sure the power con-

troller circuit breaker is on.
6.

Make sure the top cover door is closed and latched.

NOTE
If the host computer reports data (read/write)
errors, your first action should be to clean the
tape path.

TROUBLESHOOTING

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3.2.3

TROUBLESHOOTING

Power-On Health Check

The tape transport automatically performs the power-on
health check when you set the power switch in the far
right corner of the tape deck in the on position (1 pressed).
This built-in diagnostic checks dc power distribution
(availability of all required dc voltages on the inputs of all
electronic modules), normal operation of the control panel
indicators, and logic/interface initialization (Figure 3-1).
If the check is successful, all indicators momentarily
turn on and off. Then the LOGIC ON and FILE PRO
indicators come on, indicating the normal standby operating condition. The three-digit display will show the unit
number.

NOTE

The LOGIC ON and LOGIC OFF indicators are
used as dc power lights. LOGIC ON shows normal power status; LOGIC OFF indicates a power failure.

If a power failure is detected at power-up, a fault code
may appear on the display, the LOGIC OFF and FAULT
indicators should light up, and the LOGIC ON indicator
should go off.
NOTE

If a fault code appears on the display, press
RESET to clear the display. Then use the power
switch again to repeat the health check.

If the fault code reappears, refer to the
TU81/TA81 Pathfinder for on-site
troubleshooting procedures and Field Service
diagnostic tests to isolate the failure.

TROUBLESHOOTING

POWER
ON

IF FAULT

SERVO CONTROL

DlSSPOLAY

HEALTH CHECK

(F FAULT

SERVO CONTROL

DlSSPGLAY

INTERFACE HEALTH CHECK

FORMATTER

WRITE BOARD

FAULT

D!ngLAY

HEALTH CHECK

FORMATTER

READ-WRITE INTERFACE

IF FAULT

FORMATTER
READ BOARD HEALTH

IF EAULT

HEALTH CHECK

CHECK

_I|, D'Sé’BLAY I

{

D!SgSLAY

PRESS

RESET
SWITCH

DATA LOOPBACK

i 6

DISP4LAY

READ BOARD

IF FAULT

FORMATTER-ADAPTER
INTERFACE HEALTH CHECK

ADAPTER

]

CHECKSUM

ADAPTER

HEALTH CHECK

OPERATOR

ISPLAY
s

\FFAULT

—— FUNCTIONAL
l

SW FALLT

DISPLAY
60

;

'
SERVO CONTROL

EEPROM CHECKSUM

DISPLAY
67

DISPLAY

PANEL HEALTH CHECK
|

DISPLAY
66

IF FAULT

DIAGNOSTIC SW. FAULT

IF FAULT

DispLay

PRESS
REseT

SWITCH

INITIALIZE SERVO

CONTROL MODULE

DISPLAY UNIT
NUMBER

l LOAD TAPE

]
MA .0413.84

SHR-0455-85

Figure 3-1

Power-On Health Check Flowchart

TROUBLESHOOTING

3.2.4 Operator/Field Service Diagnostic Test 01
This test checks basic transport functions and tape
motions, including BOT/EOT tape motion, read data, and
write data. Use a write-enabled known good quality tape
for this test. The test takes about 10 minutes to complete
(with a 2400 foot tape).
Pre-Test Conditions

Power switch and LOGIC ON are on (power-on
health check is successful).
2. Tape path is clean.

. Tape is threaded through tape path and onto take-up
reel.

4. Tape is not loaded.

Top cover is closed and latched.
. Display shows unit number for this transport.
Test Procedure

Use the following procedure to perform test O1.
1.

Press the RESET switch.

Press the TEST switch on the diagnostics portion of

the control panel.

a. The DIAGNOSTICS indicator goes on.
b. The display indicates O1.

Press the EXECUTE switch.
a. Test 01 starts with the display panel 1ncrementmg
from 000, 111, 222, through 999. Make sure that
all segments of the numerical display are
functioning.

b. Make sure that all indicators except LOGIC OFF,
BOT, and FAULT are on.

c. Test 01 continues with various tape motion and

read /write exercises for approximately 10 minutes
(with 2400 feet of tape).

Test Successful

If the test runs to completion, the transport performs a
REWIND/UNLOAD operation and the digital display
indicates 00, with the FAULT/RESET indicator on. Press
the RESET switch to leave the diagnostic mode.

TROUBLESHOOTING

Test Unsuccessful

If the test is unsuccessful, the diagnostic program halts

and a numerical fault code appears on the display, with
the FAULT indicator on.

Refer to Table 3-1 and the TU81/TA81 Pathfinder for
further instructions on how to locate and check out the
probable failed FRU.
3.2.5

Tape Sticking Problem

If you have a possible tape sticking problem, run test 82.
For the test description and indications, refer to the
TU81/TA81 Pathfinder. If this test completes with the
unit number flashing on the display, replace the tape.
3.2.6

Field Service Diagnostic Listing

The TUS81/TA81 Pathfinder (EK-TUAS81-SV) lists all

the built-in Field Service troubleshooting procedures and
tests provided by the TU81 tape subsystem. Refer to this

document after you perform test 01. If there is a failure
that cannot be detected by test 01, perform troubleshoot-

ing procedures 1001 through 1003 to manually check out
the transport.
3.3

VAX-EXECUTABLE DIAGNOSTICS

This section lists and describes all

VA X-executable diag-

nostics that can be used to check out and accept a TU81

subsystem when it is installed on a VAX system. The
VA X-executable diagnostics are as follows.
1.

VAX front-end diagnostics (EVMBB)

VAX data reliability diagnostic (EVMBA)

NOTE
Refer to the documentation of the installed
Digital computer for information on how to run
and interpret the host diagnostics.
3.3.1

MS8739 Status Checking

Before running the VAX diagnostics, verify the TU81 and

I/O connection status using the SHOW DEVICE command. Then the system checks the M8739 module in

either of the following conditions.
TU81 Add-On Configuration — At system power-up, the

host automatically configures the tape unit into the system. If the M8739 fails at any time afterwards, the host is
unable to access the TUS81, and an error message is
entered in the system error log.

TROUBLESHOOTING

On-Line Operation Failure — If the M8739 fails during
normal on-line operation, the host is unable to continue to
access the TU81, and an error message is entered in the
system error log. When the operator tries to recall the
TUS8I1, the appropriate message appears on the operator’s

terminal indicating the “abnormal” status of the corresponding device.
Use SHOW DEVICE PT to check the connection to the

I/O controller and SHOW DEVICE MU to check out the
TUS&]1 transport connection.

3.3.2

VAX Front-End Diagnostic (EVMBB)

This diagnostic checks the subsystem in all basic modes of
operation and tests the TU81 logic, interface bus, and I/O

silo. It can only be performed with the host off-line.
The front-end diagnostic consists of three test sections:
DEFAULT, MANUAL, and FAULT. For acceptance

testing purposes, when the TUS81 is checked at system
initialization, transport add-on, or after repairs, only the

DEFAULT and MANUAL sections are used. All three
test sections are used for routine testing of the TUSI
subsystem. Each section contains several tests that check

various modules and functions of the TU81 subsystem.
DEFAULT Section

The DEFAULT section tests do not require magnetic

tape. This section is used to check the subsystem interface.
The section contains the nine tests listed below. It executes

by either of these commands.
DS»

RUN

EVMBB

DS»

START

NOTE
DS> is the prompt from the diagnostic supervisor. Do not type DS>.

JU——

Tests:

Power-up initialization test
Steps 1-3 initialization test
Diagnostic SA wrap test
Vector and BR level test

Purge and poll test
Small ring buffer initialization test

Large ring buffer initialization test

Get DUST status test

TROUBLESHOOTING

To start an individual test in this section, enter
DSy

START/TEST:n

where n is a test number from 1 to 9.

The diagnostic will begin at the specified test and proceed until the end of the section.
MANUAL Section

The MANUAL section test requires operator intervention
to mount and remove the magnetic tape when requested
by the diagnostic through the console terminal. This sec-

tion runs the preselected transport microdiagnostic test 01,
which is designated test 10 in this section.
To start the section, use this command.
DS>»

RUN

EVMBB/SEC=MANUAL

FAULT Section

This section requires operator intervention to mount and
remove the magnetic tape when requested by the diagnos-

tics through the console terminal. This section runs
preselected transport microdiagnostics consisting of three
tests (tests 11 through 13).

To start the section, enter this command.
DS»

RUN

EVMBB/SEC=FAULT

The tests are as follows.
Test 11 — Tension fault isolation

(drive resident test 02)
Test 12 — Velocity fault isolation

(drive resident test 03)
Test 13 — Select a drive resident test

(tests 01 to 99)
To select an individual test, enter
DS>»

RUN

EVMBB/SEC=FAULT/TEST:n

where n is any number from 11 to 13.

TROUBLESHOOTING

To run test 13, use the following example.
DS» START/SEC=FAULT/TEST=13

Testing:
Test 13:

_MUAOD
Select a Drive Resident

Enter

the TU81

Enter

the drive resident

READY?

[(No),

Drive

Yesl

Unit

Number:

test

Test

(1--99)

number

¢1--993:

3.3.3 VAX Data Reliability Diagnostic (EVMBA)
This diagnostic provides a complete tape subsystem checkout. It allows you to test the TU81 operation on-line without bringing the system down. The EVMBA consists of
three test sections (a total of five tests) as follows.

DEFAULT Section
Acceptance test (test 1)
Qualification test (test 2)
Multidrive test (test 3)
MEDIA Section

Read interchange test (test 4)
CONVERSATION Section

Conversation mode test (test 5)

To initiate a complete EVMBA run, load EVMBA and
enter either of these commands.
DS> RUN EVMBA
or

DS>

START

To run any of the sections, enter the section start command, for example:
DS>»

START/SEC=MEDIA

To run an individual test in the DEFAULT section, enter
DS» START/SEC = DEFAULT/TEST:n

where n is 2 number from 1 to 3.

TROUBLESHOOTING

3.3.4

Basic Operating Instructions for VAX-Based

Diagnostics
Follow these instructions when running VAX diagnostics.
1.

Load the diagnostic supervisor (ENSAA, ECSAA, or

ESSAA) for the applicable computer system.
NOTE
Use ENSAA on the VAX-11/730.
Use ECSAA on the VAX-11/750.
Use ESSAA on the VAX-11/780.
.

Attach and select the devices to be loaded in one of
two ways.
a.

Prompt mode
Attach the UNIBUS adapter to the appropriate

bus.
DS»

Load

DS»

Attach

EVMBX

Device Type?

DWXXX

(where XXX is 780, 750, or 730)
Device

Link?

HUB DWO 3

Attach the tape transport.
DS»

Attach

Device Type?

TU8T

Device

Link?

DWO

Device

Name?

MUAQ

CSR?

774500

Vector?

260

BR?

DS»

Start/Switches

Explicit mode
DS»
DS>»
DS»
DS»
DS»

Load EVMBX
Attach DWXXX
Attach TU81
Select

HUB DWO 3 4
DWO MUAO 774500

260

MUAOD

Start/Switches

NOTES
1. In the above diagnostics, no hard errors are
allowed.

. For control flags, refer to the VAX diagnostic listings.

. Load EVMBB by booting from a load media
device; for example, type »B/10 DXxxXx (DXXX
= BOOT device).

TROUBLESHOOTING

Example:
NOTE

responses

following

procedure.

Initialize and log in on

2. Check
SHOW

are

Operator

the

subsystem

underlined

the

the VAX system.

using

availability

the

DEVICE command.

SHOW DEV PT

SHOW DEV MU

(Checks 1/0 connection and status.)
(Checks TUS&I transport status.)

«#

Perform the EVMBA diagnostic.
$

ESSAA

DIAGNOSTIC SUPERVISOR,
DS»
DS>

LOAD EVMBA
ATTACH DW780

DS»
DS»

SELECT MUAO
START

ZZ-ESSAA-

HUB DWO 3 4

DS» ATTACH TUu81 DWO MUAQO 774500 260 5

4. Continue with the EVMBB diagnostic.

LLoad EVMBB by booting from a load media device.
»»> B/10 DUAD

(DUAO = RASI1)

DIAGNOSTIC SUPERVISOR,
DSy LOAD EVMBB
DSy ATTACH DW780

ZZ-ESSAA

HUB DWO 3 4

DS» ATTACH TU81 DWO MUAD 774500 260 5
DSy
DS»

3.3.5

SELECT MUAQD
START/Switches

System Exerciser

The system exerciser (UETP) for the TU81 is fully supported under VAX/VMS Version 3.6, but it is not supported in VAX/VMS Version 3.5. However, it is possible
to run TU81 under VMS Version 3.5 if you modify the
UETP data file slightly.

Edit the file [UETSUPDEV.DAT] to include the new

line as follows.
02 03 UETTAPEDOO.EXE

'TU77

02 08 UETTAPEDO.EXE 'Tus1

02 05 UETTAPEDO.EXE 'TU78

—Add this line.
‘

TROUBLESHOOTING

EVMBB Sample Error Printout

3.3.6

The following is an example of the error printout that is
returned whenever the TU81 fails to execute a drive resident diagnostic while running under EVMBB.

t+223% [UMBB TUB81 FRONT-END/HOST DIAGNOSTIC - 2.0 **##**
PASS 1, TEST 13, SUBTEST 0, ERROR 18, 18-MAY-1984 10:53:27.13
HARD ERROR WHILE TESTING MUAO: INTERNAL DIAGNOSTIC FAILED
SA =

0000 (X)
FAULT CODE = 09
SUBFAULT CODE = 03
$ SHOW DEV PT

$ SHOW DEV MU

3.4 PDP-11-EXECUTABLE DIAGNOSTICS
This section lists and describes all PDP-11-executable
diagnostics that can be used to check out and accept a
TU81 subsystem installed on a PDP-11 system.
NOTE
Refer to the documentation of the installed
Digital computer for information on how to run
and interpret the host diagnostics.
3.4.1

Operating

Instructions

Diagnostics
Follow this procedure

for

PDP-11-Based

using

PDP-11-based

|
when

diagnostics.
1.

Load XXDP+ monitor.
a.

Enter date

Answer hard core questions.
a. 50 Hz? Yor N

b.LSI? Yor N
This

(Help

XXDP+.

Type

H/L

for

File).

[Receive XXDP+ prompt (dot)]
3.

Enter R (space) program name.
The program may be CZTU2 or CZTUI.

The operator entry should look like this.
[.R

2TU2?7?]

Receive DR> prompt.

details

TROUBLESHOOTING

Enter the appropriate command.
For example,
start the

test.

DR>STA to
Change

HW(L)? Y or

Change

SW(L)?

3.4.2

Y or

CZTU2 Front End Functional Diagnostic

CZTU2 is the first host level diagnostic run, since it tests
the basic functionality of the TU81 subsystem.
CZTU?2 tests up to four TU81 subsystems. To run a full
pass of the program, a scratch tape must be mounted on
the transport and an operator must be present to perform
manual intervention.

The first pass of the program is a “‘quick verify”. For a
single unit under test, the first pass takes about 20 minutes. All subsequent passes run multiple iterations of each
test listed below; these passes each take about 24 minutes
for a single unit under test.
Test 001:Existence Verification Test
Test 002:Initialization Test
Test 003:Initialization Test
Test 004:SA Register Wrap Test
Test 005:Vector and BR Level Test
Test 006:Purge and Poll Test
Test 007:Small Ring Test
Test 008:Maximum Ring Buffer Test
Test 009:Get DUST Status
Test 010:Functional Fault Detection Test
(Internal Drive Test 1)
Test 011:Tension Fault Isolation Test
(Internal Drive Test 2)
Test 012:Velocity Fault Isolation Test
(Internal Drive Test 3)

Test 013:Select A Drive Resident Test
(Internal Drive Tests 1-99)

3.4.3 CZTU1 Data Reliability Test
This diagnostic tests the performance quality of the TUSI
subsystem.

CZTUI! tests up to four TU81 subsystems. A scratch
tape must be mounted on the transport to run this test.
Each pass takes about 1 hour and 10 minutes for each unit
under test.

TROUBLESHOOTING

Test 001:Basic Function Test

Test 002:Quick Verify Read/Write Test
Test 003:Complex Read/Write Test
Test 004:Write Interchange Tape
Test 005:Read Unknown Tape

Test 006:Start/Stop Write/Read Test
Test 007:Conversation Test

3.44

CXTUCA DEC/X11 Module

This module streams the drive in both read and write
modes. Each pass begins where the previous pass left off.
In effect the entire reel of tape is written and read.

CXTUCA tests a single TU81 subsystem.
3.5

ASCII PORT DIAGNOSTICS

When connected to a hand-held or console terminal, the
ASCII port (Figure 3-2) serves as an input/output device
to perform the following functions.

1. Run the transport resident diagnostics
2.

Display or print out error log information (sense

bytes)
3.

Run special test 27 (conversation mode test using
selective parameters)
NOTE
Appendix A lists the sense bytes and ASCII
addresses.

ASCHI PORT PANEL

EIA CABLE

MA-1173-83

Figure 3-2

ASCII Port and EIA Cable

TROUBLESHOOTING

The ASCII port is located on the left side of the TUS81
control panel (under the cover). To use the port, open the
cover and plug in an RS232-compatible terminal into the
EIA 25-position terminal 1/O connector.
NOTE

The ASCII port accepts and generates the full
ASCII character set. Certain characters are

ignored or have special meaning as defined in
Table 3-2.

Table 3-2

Control Commands

Control Character

Description

CONTROL/C (ETX)
CONTROL/Y (EM)

Gains the attention of the ASCII
control program. Other commands
may follow. It can also be issued to
abort the run of the current command, program, or diagnostic.

CONTROL/G (BEL)

When received by the terminal, causes
an audible sound (BELL) from the
terminal. The ASCII control program
treats it as an illegal character.

BACKSPACE (BS) or
CONTROL/H

When received by a video terminal,
overwrites the previously displayed
character.

LINEFEED (LF) or
CONTROL/J

Used to start any line of text output.

RETURN (CR) or
CONTROL/M

Used to signal the end of an input
line.

CONTROL/O (SI)

Used to toggle the output to the
ASCII terminal on or off. With the
output toggled off, the characters that
are being sent to the terminal are not
displayed. The program continues to
run.

XON (DX1) or
CONTROL/Q

Generated by the terminal to start the
output aborted by the previous
CONTROL/S.

TROUBLESHOOTING

Table 3-2

Control Commands (Cont)

Control Character

Description

XOFF (DC3) or

Generated by the terminal to stop the

CONTROL/S

ASCII control program from sending
characters to it. The program generating

the output stops running until a

CONTROL/Q is received.
CONTROL/U (NAK)

Generated by the terminal to tell the
ASCII control program to delete and
abort the current input and reissue the
command prompt.

CONTROL/Z (SUB)

Generated by the terminal to signal
the end of a transaction. If this command is entered at the command
prompt, the ASCII control program

ignores further terminal input, reversing the initial CONTROL/C or /Y
command.
DELETE (DEL)

Generated by the terminal to erase the
previously entered character. On a

video terminal, in the default mode,
DELETE is echoed as BACKSPACE,

SPACE, BACKSPACE. On a hardcopy terminal (set up with the command

SET TERMINAL/NOSCOPE or

/HARDCOPY listed in Table 3-3),
DELETE is echoed as \, echo of

deleted characters, \. DELETE does

not delete past the end of the prompt.

NOTE
The ASCII port’s control program generates no
special characters except CONTROL/G, indicating an illegal input character; and CON-

TROL/J and CONTROL/M for formatting the
output. Any control character not mentioned in

this table as valid input generates BELL if
received.

3.5.1

TROUBLESHOOTING

Port Access

To communicate with the ASCII port, proceed as follows.
a.

Take the TUS81 off-line from the host system.

b. Type CONTROL/C or CONTROL/Y.

Characters typed earlier will be ignored.

Mount a scratch tape and enter CONTROL/M (or
RETURN) to continue the operation.

The ASCII port’s control program gives the command level prompt, indicating it is ready for an input
command. The prompt is TU81>.

Enter a command from Table 3-3.

If you want to run the transport diagnostics, enter the
default RUN DIAGNOSTICS command or RUN
DIAGNOSTICS/TEST=xx to execute a particular
test (for example, from the TU81/TA8I1 Pathfinder
(EK-TUAS81-SV). Refer to Paragraph 3.5.2 to set up
specific options.

If the test is successful, the terminal responds with
the TU81> prompt.

If the test fails, the terminal displays the diagnostic
message specifying the fault condition. (Refer to Paragraph 3.5.3.)

Type CONTROL/Z or EXIT to exit from the ASCII

terminal mode. The TU81 echoes with " Z.

The control program will disconnect after 10 idle minutes if there is no input at the command prompt level. Any
characters typed in before the TU81> prompt are ignored.

TROUBLESHOOTING
Table 3-3

Operating Commands

Command

Description

SET TERMINAL

/SCOPE - (Default) Indicates that
the terminal in use is a video display
terminal.

/HARDCOPY or /NOSCOPE Indicates that the terminal in use is a
hardcopy (printing) unit.
SET DIAGNOSTIC

/LOOP - Enables loop-on-error mode.
/NOLOOP - (Default) Disables
loop-on-error.

/HALT - Enables halt-on-error; exits
to TU81> prompt ending the test.
/NO HALT - (Default) Disables
halt-on-error.

SHOW DEVICE

Displays the device unit type and
device serial number.

SHOW RADIX

Displays the number base of numeric
outputs; in TU81s the radix is
decimal.

SHOW VERSION

Displays the hardware and microcode
version levels.

RUN DIAGNOSTICS

(Default) Starts the power-up
diagnostic test.

RUN DIAGNOSTICS/ Selects a diagnostic test number where
TEST=xx

xx represents two decimal digits.

EXIT

Exits the TU81 from the terminal
mode. After exit, the TU81 no longer
responds to the external ASCII
terminal except for the CONTROL/C
input command.

CONTROL/Z

Same as EXIT, echoes with ®Z. Also,
used to return the SET mode to
default values.

TROUBLESHOOTING

3.5.2 Diagnostic Commands
The diagnostic commands are used to check the TUS8I
status, and to set up and control the diagnostic execution.
To set a diagnostic control parameter, you should enter
the proper SET command before starting the test. Once
specified, the parameter remains in effect until changed
with another command or until you exit from the terminal
mode.
|
If no SET parameters were specified, the ASCII control
program automatically uses the default parameters, which
remain active until you use a SET command. For example, you can run the selected test with “no loop on error”
and “no halt on error” defaults. In this case the test runs
for one pass only.
Type diagnostic commands immediately after the
prompt with no spaces between. Separate the command
from the first parameter by one space. If you invoke
options, enter them after the first parameter, with a slash
between the two terms. One option per command is
allowed.
3.5.3

Message Format

Each input line together with the command prompt should
not be greater than 64 characters. Characters beyond the
64th are ignored by the control program. All inputs from
the terminal (except CONTROL/C and /Y) are prompted for.
Diagnostic Messages

Diagnostic results are reported in the following format if
the test is unsuccessful (maximum 64 characters per line).
TEST:xx FAULT CODE:xx FAULT SUBCODE:xx
where

TEST:xx

= Diagnostic test number
(in decimal)

FAULT CODE:xx

= Code indicating primary

field replaceable unit
FAULT SUBCODE:xx = Code indicating hardware
element that failed

Successful completion of a diagnostic test causes the
prompt to be displayed. Refer to the TU81/TA81 Pathfinder (EK-TUAS81-SV) tables for additional instructions
in the event of a diagnostic failure.

TROUBLESHOOTING

3.5.4

Special Diagnostic Test 27

Test 27 is not a resident microdiagnostic permanently
stored in the TU81 memory. This diagnostic can only be
performed using a terminal since it requires manual data
input.

Test Procedure
Put unit on-line.

Enter the command
RUN

DIAGNOSTICS/TEST=27.

This causes three commands to be executed in the following order.
1.

Write

Backspace

Read

When the prompt appears on the terminal, enter the first
input parameter, selecting speed and density. As each
additional prompt appears, enter additional input parameters in the specified order.
TU81> Speed and density select where

TU81> Pattern identifier where

1 = all ones

2 = all zeros
3 = alternating bytes of ones and zeros
4 = worst case PE pattern
3 1s

20s

bytel

3 1s

3 Os
3 1s

byte 2

TROUBLESHOOTING

Tus1> Bytes/block where
1 = 512 bytes
2 = 2048 bytes

Tus 1> Write block count: XXX where
XXX =0 to 255

Tus 1> Backspace block count: XXX where
XXX =0 to 255

Tug 1> Read block count where
XXX =0 to 255

Example:

Entering the following causes 16 blocks of 2048 bytes
of ones to be written at 25 ips PE. Then a backspace of 16
blocks occurs, and the 16 blocks are read.
1

TU81>»
TUB1>
TUB1>»

TU81>»
TU81>
Tu81>»

16
16
16

If you enter zero in a block count field, the correspond-

ing command is not executed.
Enter all parameters as decimal numbers.
After receiving the input parameters, the TU81 per-

forms a rewind to BOT. This is necessary because a density change can only be made when the tape is positioned at
BOT.

TROUBLESHOOTING

Default Parameter Values
If you type CONTROL/Z immediately after entering:

RUN DIAGNOSTICS/TEST =

the input parameters revert to these default values.

Speed and density select

(25 ips PE)

Pattern identifier

(alternating ones and
Zeros)

Bytes/block

(512 bytes)

Write block count

Backspace block count

Read block count

If you enter CONTROL/Z during parameter selection,
default values are assumed for the remaining parameters.

System Conflicts
If the unit is on-line to the host when the ASCII port is
activated, the following message will be displayed on the

terminal.
TU81

ONLINE

USE

ASCII

HOST.

PORT,

TAKE

UNIT

OFFLINE!

3.6

MAINTENANCE INDICATORS AND FAULT/
ERROR CODES
|
The four methods that a TU81 subsystem uses to display
error and status conditions are, in order of decreasing

severity:

1.
2.

Lighting the controller fail indicator,
Depositing a fatal error code in the /O page SA

3. Displaying a fault code on the operator panel, and
4.

Sending a TMSCP error log packet with error/status

code to the host.

TROUBLESHOOTING

A TURI subsystem uses these four methods in different
combinations, depending on the type and severity of the

particular error.
®

Fatal errors (detected by internal microdiagnostic
routines or other checks in the master drive’s control-

ler) light the controller fail indicator and leave a fatal
error code in the host system I/O page SA register.

e TMSCP command errors return error codes and send
corresponding error log packets to the

host,

enabled.

Table 3-4 lists the assigned fatal error codes and the
reason for the error. Error codes in the range of 100001
through 100026 (octal) are generic TMSCP controller
codes; error codes in the range of 100454 through 100460
are specific to the TU81. These codes can be printed out

while running host level diagnostics, or they can be
accessed by reading the SA register (default 774502(8) or

F942(16)). All of these codes include bit 15 set so that any
time the host finds bit 15 of the SA set, it knows that one
of these errors has occurred. Host level diagnostics print

out the code, including bit 15. Paragraph 3.7 and Table
3-5 describe all TMSCP end/error log packet codes.
[

Table 3-4 TMSCP Fatal Error Codes Déposited into SA
Register

Error Code

Octal

Hexadecimal Description

100001

8001

Command packet read error
(parity or timeout)

100002

8002

Response packet write error
(parity or timeout)

100003

8003

Controller ROM and RAM parity

100004

8004

Controller RAM parity

100005

8005

Controller ROM parity

100006

8006

Ring read error (parity or timeout)

TROUBLESHOOTING
Table 3-4

TMSCP Fatal Error Codes Deposited into SA
Register (Cont)

Error Code

Octal

Hexadecimal Description

100007

8007

Ring write error (parity or

timeout)
100010

8008

100011

8009

Interrupt failure

Host access timeout (TMSCP

dependent)
100012

800A

Command limit exceeded (reporting this condition optional)

100013

800B

Bus Master error

100014

800C

Diagnostic controller fatal error

100015

800D

Instruction loop timeout

100016

800E

Invalid connection identifier

100017

800F

Error on interrupt write

100022

8012

RAM error (non-parity)

100023

8013
-

Port initialization sequence
error

100024

8014

Wrong TMSCP version

100025

8015

Perge/Poll hardware failure

100026

8016

Map table entry read error

100454

812C

TMSCP version number error

100455

812D

TMSCP hardware failure

100456

812E

Unknown interrupt

100457

812F

Own Bit not set

100460

8130

Pulse AC Clear unsuccessful

TROUBLESHOOTING

3.7

OPERATING SYSTEM ERROR LOG DECODING AND TROUBLESHOOTING

Status/error codes pass from the TMSCP server (in the
TU81) to the TMSCP class driver (in the host). Hard
TMSCP command errors, such as trying to read from a
drive that is off-line, return a TMSCP error code in the
command’s end packet. Other nonfatal errors that occur
during a command’s execution return an error code in the
command’s end packet only if the error cannot be recovered after retries (hard).

Most of these nonfatal errors also try to send an error
log packet to the host even if the error is recoverable or if
there is a correlating TMSCP command. However, log
packets are sent only if the host has explicitly enabled
logging. The drive can send any combination of end/log
packet status/error codes.

All status and error codes use the same format (Figure
3-3). A 5-bit major code occupies bits 04 through 00 and
an 11-bit minor code occupies bits 15 through 05. (For
- TMSCP conventions, the major code is the device code
and the minor code is the subdevice code.) Most of the
error log report generators in Digital’s operating system
decode the packets and provide text descriptions for the
major and minor codes. However, host-based diagnostics
and utilities may provide only the numeric code. A full 16-

bit code, or perhaps just the 11-bit minor component, may
be provided.

Table 3-5 lists all major and minor codes returned to the
system by the TUS81. The table is broken into sections, and
each major code occupies a section. The major codes are
listed by name and are in numeric order. The minor codes
and descriptions follow.

For example, if the system logs a 177713 (octal) error,
reduce the code to a major code of 13 (bits 04 through 00)
and a minor code of 3776 (bits 15 through 05). Now refer
to Table 3-5. Major code 13 is a drive error. Under the
drive error section, minor code 3776 is an error caused
when the drive could not position for Retry.

TROUBLESHOOTING

BIT NUMBER
15

ISD10[ SD9 l SD8 | sD7 | sD6 | SD5 | sD4 l SD3 l SD2 l SD1 lSDO I D4 D3 I D2

11-BIT

]

D1 l Do I
—

5-BIT

SUB-DEVICE CODE
(MINOR CODE)

DEVICE CODE
(MAJOR CODE)
MA1317-83
SHR-0454-8B5

Figure 3-3

Error/Status Code Word Format

Table 3-5

TMSCP Status and Event Codes

Major
Code
Name

Minor Full
Octal Octal
Code Code

Full
Hex.
Code

Minor
Code
Name

Success
(xxxx00)

0000

000000

0000

Normal success
(no error)

0010

000400

0100

Already on-line

0040

002000

0400

EOT detected

0000

000001

0001

Invalid MSG length

0100

004001 0801

Invalid opcode

0120

005001

OAO1

Invalid modifiers

0140

006001

0CO1

Invalid byte count
or Invalid TMSCP version

0160

007001

OEO1

Invalid unit flags
or Invalid controller
flags

0400

020001

2001

Invalid format

Invalid
command

(xxxx01)

Command

No substatus codes

aborted

apply

(xxxx02)

TROUBLESHOOTING

Table 3-5

TMSCP Status and Event Codes (Cont)

Major

Minor Full

Full

Minor

Code

Octal Octal

Hex.

‘Name

Code

Code
Name

Unit

0000

000003

0003

Unit unknown or on-line

off-line

to another controller

(xxxx03)
0001

000043

0023

No media loaded

0002

000103

0043

Unit is inoperative

Unit

No substatus codes

available

apply

(xxxx04)
Unit write

0200

010006

1006

protected

Unit is software write

protected

(xxxx06)
0400

020006

2006

Unit is hardware write

protected
0600

030006

3006

Unit is software and

hardware write protected
Compare

No substatus codes

error

used

(xxxx07)
Data error

0000

000010

0008

Long Gap encountered

0001

000050

0028

AGC fault

0002

000110

0048

ID fault

0003

000150

0068

Read data check

0004

000210

0088

Unit exception

0005

000250

00A8

FIFO Overrun/Overflow

0006

000310

00C8

FMTR read parity error

0007

000350

OOE8

Unrecoverable read error

0010

000410

0108

FIFO parity error

0011

000450

0128

I/F parity error

(xxxx10)

TROUBLESHOOTING

Table 3-5

TMSCP Status and Event Codes (Cont)

Major

Minor Full

Full

Minor

Code

Octal Octal

Hex.

Code

Name

Code

Name

0012

000510

0148

LESI parity error

3773

177550

FF68

Formatter Retry sequence

exhausted
3774

177610

FF88

Controller transfer Retry
limit exceeded

3775

177650

FFAR

Host requested Retry
suppression on a K.sti
detected error

3776

177710

FFCR8

Reverse Retry currently
not supported

3777

177750

FFESR

Host requested Retry
suppression on a Formatter
detected error

0003

000151

0069

Nonexistent memory

(xxxx11)

0004

000211

0089

Host bus/memory
parity error

Controller

0000

000012

000A

Gross Time Out

(xxxx12)

0001

000052

002A

Data late

Drive error

0000

000013

000B

Device response check

0001

000053

002B

Device hardware check

0002

000113

004B

Velocity check

0003

000153 006B

0004

000213

008B

Airflow/Temperature
check

3761

177053

FE2B

Could not save byte

Host buffer
access error

crror

(xxxx13)

Device command check

count

3762

177113

FE4B

Could not write tape
mark

3763

177153

FE6B

Could not set unit
characteristics

TROUBLESHOOTING

Table 3-5
Major
Code
Name

TMSCP Status and Event Codes (Cont)
Minor Full
Octal Octal
Code Code

Full

Minor

Hex.

Code

Name

Unable to position
to before LEOT

3764

177213

FE8B

3765

177253

FEAB Rewind failure

3766

177313

FECB Could not complete
on-line sequence

3767

177353

FEEB

Erase Gap failed

3770

177413

FFOB

Erase failed

37173

177553

FF6B

Tape drive requested
error log

3776

177713

FFCB

Could not position
for (Formatter) Retry

37717

177753

FFEB

Cannot clear drive
errors

Formatter

0001

000054

002C

Equipment check

0002

000114

004C

Intervention required

0003

000154

006C

Command reject

0004

000214

008C

error

(xxxx14)

Formatter response

check
0005

000254

00AC

Formatter sense read
error

3757

176754

FDEC Could not get extended
drive status

3760

177014

FEOC

Could not get formatter
summary status while
trying to restore tape

position
3770

177414

FFOC

Topology command failed

3773

177554

FF6C

Formatter requested
error log

TROUBLESHOOTING
Table 3-5

TMSCP Status and Event Codes (Cont)

Major

Minor Full

Full

Minor

Code

Octal Octal

Hex.

Code

Name

Code

Name

3776

177714

FFCC

Cannot clear formatter
errors

3777

177754

FFEC

Could not get formatter

summary status during
transfer error recovery
BOT

No substatus codes

Encountered used

(xxxx15)

;

Tape Mark

No substatus codes

detected

used

(xxxx16)
Recorded

No substatus codes

Data

used

truncated

(xxxx20)

Position

3771

177461

FF31

Retry limit exceeded

lost error

when attempting to

(xxxx21)

restore tape position
3773

177561

FF71

Formatter detected
position lost

3776

177721

FFD1

)

Formatter and controller

disagree on tape position

{

3777 177761 FFFl

Controller detected
position lost

Serious

No substatus codes

Exception

used

Condition
Present

(xxxx22)

LEOT

No substatus codes

detected

used

REMOVAL AND
REPLACEMENT
This chapter describes the removal and replacement procedures for the TU81 components and modules listed in
the field replaceable unit table (Table 1-1). Each proce-

dure also gives a test (or tests) to be performed that checks
the replaced module.

The removal and replacement procedures follow the
concept of module (assembly) replacement only. Individual circuit troubleshooting or assembly repair are not recommended and are, therefore, not discussed in this guide.
NOTE

Unless otherwise specified, in all procedures it
is assumed that the tape has been unloaded, the
transport is powered down, and the power cord
is disconnected.
CAUTION

When replacing electronic modules (PCBs), be

careful to properly ground yourself to protect
MOS components from static electricity. Do
not touch MOS IC pins if you are not grounded.

4.1 ACCESS TO TAPE DECK COMPONENTS
Components located on the underside of the tape deck can
be accessed for maintenance purposes by placing the tape
deck in the maintenance position. Using Figure 4-1 for
reference, proceed as follows.

1. Open the top cover fully.

2. Using a 5/32 inch allen wrench, open the front door.
3. Using a straight slot screwdriver, rotate the pawl fastener on the front left corner of the tape deck onequarter turn counterclockwise to release the deck.
Rotate the fastener six more turns counterclockwise
to disengage the pawl fully.

4. While pressing down on the front of the tape deck,
pull the spring-loaded tape deck latch out. With the
Jatch extended, pull the tape deck upward and allow
the front of the tape deck to rise.

REMOVAL AND REPLACEMENT

PAWL

FASTENER

/////////LATCH

FRONT DOOR

(a) OPERATING POSITION

\
MA-0076-83

SHR-0331-85

FLAT I/O CABLE

IN LOGIC CAGE

EXTERNAL

/0 CABLE

(b) MAINTENANCE POSITION
MA-1174-83

Figure 4-1

TUS81 Maintenance Access

SHR-0457-85

REMOVAL AND REPLACEMENT

5. Release the tape deck latch and manually tilt the
front of the tape deck up until the latch engages and
the tape deck is locked in the vertical (maintenance)
position.

From the vertical position, the tape deck may be
moved to the tilted position for maintenance if
desired. To move the tape deck from the vertical to
the tilted position, push the top of the tape deck back
slightly to relieve pressure on the latch and pull out
the latch. Keep pushing the top of the tape deck back
until the latch engages in the tilted position.
CAUTION

Be careful not to snag or chafe the control panel
cable or any other cables when positioning the
tape deck.

To return the tape deck to the operating position, pull

the tape deck latch out and manually place the deck
in the horizontal position until the latch engages.
Secure the tape deck by turning the pawl fastener
clockwise.

NOTE

When servicing the transport, you may need to
operate the unit and run diagnostic tests with
the top cover open. To bypass the safety interlock switch, insert the interlock defeat tool
(supplied in the CD kit) into the interlock latch.
This keeps the interlock switch pressed down,
simulating the “top cover closed” condition.
Refer to Paragraph 1.8.3 and Figure 1-11.

Figure 4-2 shows the drive’s module (assembly) layout with the tape deck in the maintenance (vertical)
position.

REMOVAL AND REPLACEMENT

TWO LOGIC

CAGES

PLENUM/FILTER

\\\\5%§;;///BOX

: j’) CAPACITOR

ILI TAKE—-UP
REEL

MOTOR
1000 LINE
TACHOMETER
COMPRESSOR

POWER
|
Q

«—————AMPLIFIER

U\JLA

MODULE

T——SUPPLY
T
I

REEL

MOTOR

*——pPOWER
SUPPLY

COOLING

LINE
TACHOMETER

FAN
MA-0498.84

Figure 4-2

Tape Deck Layout

REMOVAL AND REPLACEMENT

4.2

PROTECTIVE DRIVE COVER

Removal

1. Place the tape deck in the maintenance position
(Paragraph 4.1).

2. Loosen the three wing nuts and three thumbscrews
securing the cover and remove the cover assembly
(Figure 4-3).

Replacement

1. Place the drive cover in position so that the cooling
fan wires are placed in the feed-through holes (Figure
4-3).

2. Secure the cover with the three nuts and three screws.

3. Return the tape deck to the operating position.

MA .0456-84

Figure 4-3

Protective Drive Cover

REMOVAL AND REPLACEMENT
4.3

TAPE CLEANER ASSEMBLY

Removal
1.

Remove the tape path and magnetic head covers

from the tape deck.
2.

Loosen the two mounting screws and remove the

cleaner assembly from the tape deck (Figure 4-4).
3.

Remove the screws, lockwashers, and cover plate

from the blade housing.

4. Slide the platform out from the tape cleaner
assembly.

CAUTION
Handle the assembly with care. The cleaner
'

blades are both brittle and sharp.

NOTE
The defective tape cleaner must be replaced as acomplete assembly.

MOUNTING

SCREW

TAPE CLEANER

”

ASSEMBLY

MA-0081-83

Figure 4-4

Tape Cleaner Assembly

REMOVAL AND REPLACEMENT

Replacement
1.

Inspect the cleaner blades for damage. If the blades
are chipped or damaged, replace the entire assembly.

If the blades are not damaged, clean the platform and
reinstall. When installing the platform, make sure
that the flanges are positioned so that the platform
fits firmly inside the cleaner assembly.
Install the cover plate, two lockwashers, and mounting screws.

Position the assembly onto the guide pins on the tape
deck and tighten the screws.

Reinstall the tape path and magnetic head covers.

Verification Check
1.

No functional checks are necessary.

TOP COVER INTERLOCK SWITCH

Removal
1.

With the tape deck in the maintenance position,

remove the four labeled slip-on connectors from the
interlock switch connectors. (If any wires are not
labeled, identify and mark each wire for reassembly.)
See Figure 4-5.
.

Remeove the two mounting screws securing the switch
plate to the tape deck. Remove the switch and switch

plate.

Press the top and bottom release tabs on the switch to
separate the switch from the switch plate.
Replacement

Assemble the switch to the switch plate.
Position the switch assembly on the rear of the tape
deck so that the connector numbers on the switch
correspond to the numbers stenciled on the tape deck.

REMOVAL AND REPLACEMENT

P3-11
P9-31
P10-32

P4-12

MA-0077-83

Figure 4-5

Top Cover Interlock Switch (Maintenance
View)

Insert the two hex mounting screws. Position the top

cover door so that the interlock switch can be aligned
with the actuating stud on the door. Tighten the
switch mounting screws when the center of the switch
front is aligned with the actuating stud.
4.

Attach the slip-on connectors to the appropriate studs
of the interlock switch. Refer to Figure 4-5 for wire
and connector positions.

Verification Check

1. With the tape threaded but not loaded, execute operator diagnostic test O1.

REMOVAL AND REPLACEMENT

4.5

FILE PROTECT SENSOR

Removal

1. Remove the tape reel from the supply hub.

2. Remove the four mounting screws (Figure 4-6) and
the file protect sensor cover plate from the tape deck.
3. Remove the mounting screw and washer securing the
file protect sensor to the tape deck.

4. Detach connector W3P6 from the sensor and discard
the sensor.
Replacement

NOTE

Refer to Figure 4-6 for sensor alignment and
cable plug connection.

1. Place the sensor on the tape deck and secure it with
the mounting screw and washer.

2. Attach connector W3P6 to the sensor pins.

3. Reinstall the sensor cover plate and secure it to the
tape deck with the four mounting screws.

ALIGN FLUSHWITH

W3P6

TAPE DECK CUTOUT

PLATE MOUNTING

SCREW HOLES
MA-0464-82

Figure 4-6

File Protect Sensor Alignment

REMOVAL AND REPLACEMENT

Verification Checks

Thread a write enabled tape and perform a load oper-

ation. Observe that the FILE PRO indicator is not
lighted.

4.6

Unload the tape and remove the write enable ring.
Thread the tape, perform a load operation, and
observe that the FILE PRO indicator is lighted.

EOT/BOT SENSOR ASSEMBLY

Removal
1.

Remove the tape path and magnetic head covers
from the tape deck.

Remove connector W3P1
assembly.

Remove the flat-head phillips mounting screw from

from the EOT/BOT

the assembly base mount and then lift the assembly
from the tape deck (Figure 4-7).

NOTE
You must replace the defective sensor as a complete assembly.

EOT/BOT
ASSEMBLY

MA-0458-82

Figure 4-7

EOT/BOT Sensor Assembly

REMOVAL AND REPLACEMENT

Replacement

1. Position the EOT/BOT assembly onto the tape deck
and install the flat-head mounting screw.

2. Thread the tape onto the take-up reel. Align the
EOT/BOT assembly with the tape.

3. Tighten the flat-head mounting screw.

4. Reattach connector W3P1 to the sensor assembly. If
excess cable exists, position the cable so that the
excess is at the rear of the tape deck.
5. Install the tape path and magnetic head covers.
Vertification Checks
NOTE

If available, use a 600 foot reel of tape with
properly installed EOT/BOT markers to reduce
test time.

1. Load a reel of tape onto the supply hub and thread
the tape so that the BOT marker is located before the
EOT/BOT assembly.

2. Perform a load operation and observe that the tape
loads and positions itself at the BOT marker (the
BOT indicator lights).

3. Execute Field Service test 44 to verify operation of
the EOT sensor.

4.7

TAKE-UP REEL HUB ASSEMBLY

Removal

1. Remove the four mounting screws from the take-up
reel hub cover and remove the cover from the hub
assembly (Figure 4-8).

2 Remove the three allen screws, lockwashers, and

plain washers securing the reel to the motor shaft
|
assembly.

3. Remove the take-up reel from the transport.

REMOVAL AND REPLACEMENT

CAM CARRIER

TAKE UP

REEL COVER

HUB COVER
N

— MOUNTING

SCREWS (3)
CuT-OUT

REEL MOUNTING

FOR COVER

HARDWARE

TAKE UP

REMOVAL

Y=\
[,\Q

u_l

SUPPLY REEL

HUB ASSEMBLY

MA-0463-82

Figure 4-8

Take-Up Reel and Supply Reel Hub
Assemblies

Replacement

CAUTION

If you are installing a new reel, inspect the reel
edges for burrs or cracks that could cause tape
damage.

1. Replace the take-up reel on the transport.

2. Replace the three allen screws, lockwashers, and plain
washers securing the reel to the motor shaft
assembly.

3. Replace the cover on the hub assembly and install the
four mounting screws.

REMOVAL AND REPLACEMENT

Verification Checks

. Manually rotate the tape reel to make sure that the
reel does not contact the tape deck.
. Load a known good reel of tape and observe the reel
during tape motion. The tape should not contact the
reel flanges.

TAKE-UP REEL MOTOR ASSEMBLY

4.8

Perform the removal procedure for the take-up reel
hub assembly (Paragraph 4.7).

Removal

Place the tape deck in the maintenance position and
remove the drive cover (Paragraphs 4.1 and 4.2).

. Remove connector W3P2 from the tachometer
assembly on the take-up motor.

. Remove connector B3P1 from the power amplifier
module (jack J1 on the power amplifier module).

. Remove the four mounting screws (Figure 4-9) securing the motor to the tape deck. Remove the motor
from the transport.

TAKE UP

REEL MOTOR

SENSOR MOUNTING
SCREWS (2]

\\@

COVER MOUNTING

SCREWS (2)
MA-0465-82

Figure 4-9

Take-Up Reel Motor Assembly

REMOVAL AND REPLACEMENT

Replacement

NOTE

The reel motor and tach must be replaced as an
assembly.

CAUTION

When installing the motor, make sure there are
no loose wires between the motor mounting
plate and tape deck.

. Position the motor on the rear of the tape deck so
that the B3P1 cable extends from the lower right.
Secure the motor with the four mounting screws.

. Attach connector B3P1 to J1 on the power amplifier
module.

Attach connector W3P2 to the tach assembly on the
motor.

Install the drive cover and return the tape deck to the
operating position.

. Perform the replacement procedure for the take-up
reel hub assembly.
Verification Checks
1.

Execute Field Service test 37. (Refer to diagnostics
test 37 in the TU81/TA81 Pathfinder for
requirements.)

. Execute Field Service test 48.

Thread the tape but do not load it. Execute operator
diagnostic test O1.

REMOVAL AND REPLACEMENT

4.9

SUPPLY REEL HUB ASSEMBLY

Removal

1. Press the center button on the hub to unlatch it (Figure 4-8).

2. Locate the slot opening on the periphery of the cover.
Insert a small-blade screwdriver into the slot and
twist it to unsnap the cover from the hub assembly.
3. Latch the hub assembly by pressing the cam carrier.
CAUTION

Make sure the hub is latched before you proceed with further removal. If the hub is
unlatched, parts may disassemble.

4. Remove the three large shoulder screws from the
cam carrier. Remove the hub assembly from the tape
deck.
Replacement

1. Position the hub assembly onto the motor shaft
assembly and secure it with the three large shoulder
SCTEWS.

2. Install the cover on the face of the hub assembly.
Verification Checks

1. Mount the tape reel onto the hub assembly. The reel
should mount easily onto the hub and against the
bottom flange.

2. Latch the reel onto the hub. Make sure the reel is
securely fastened.

3. Load a known good quality tape and observe the reel
during tape motion. The tape should not contact the
reel flanges.

4. With the tape threaded but not loaded, execute operator diagnostic test O1.

REMOVAL AND REPLACEMENT

4.10

SUPPLY REEL MOTOR ASSEMBLY
NOTE

The supply reel motor assembly is not supplied
as part of the spare parts list. A spare take-up
reel motor assembly must be disassembled and
the motor used as a replacement for the supply
motor.

Removal
].

Perform the removal procedure for the supply reel
hub assembly (Paragraph 4.9). Place the tape deck in
the maintenance position and remove the drive cover
(Paragraphs 4.1 and 4.2).

Remove connector B1P1 from J3 on the power
amplifier module.

Remove the tach cover and mounting screws from
the motor (Figure 4-10). Retain them for reuse.

Remove connector W3P5 from the tach assembly on
the motor.

Remove the four mounting screws securing the motor
to the tape deck. Remove the motor from the tape
deck.

Remove the mounting screw (Figure 4-10) and the
sensor from the mounting plate on the supply reel
motor. Retain them for reuse.

SUPPLY REEL

MOUNTING

MOTOR

PLATE

SCREWS (3)
SENSOR
MOUNTING

PLATE

TACH WHEEL
AND SET SCREWS

,,f}(\ W
-~

TACH

¢@\% Z'

SENSOR

COVER

COVER
MOUNTING

SCREWS (4)
MA-0461-82

Figure 4-10

Supply Reel Motor Assembly

REMOVAL AND REPLACEMENT

Loosen the two set screws securing the tach to the
motor shaft and remove the tach from the shaft.
Retain the screws and tach for reuse.
. Remove the four screws securing the mounting plate
and remove the plate from the supply reel motor.
Retain the screws and mounting plate for reuse.
Disassemble the spare take-up reel motor assembly as
follows (refer to Figure 4-9).

a. Remove the two mounting screws and the tach
cover from the motor assembly.
b. Remove the two mounting screws securing the
tach sensor to the reel motor. Remove the tach
sensor from the reel shaft and the tach wheel.
c. Loosen the set screw and remove the tach wheel
from the motor shaft.
Replacement

. Place the mounting plate (from step 8 of Removal)
onto the rear of the new motor and secure it with the
four mounting screws.

Assemble the sensor and tach wheel (from steps 6
and 7 of Removal) onto the motor mounting plate
and shaft as shown in Figure 4-11 and adjust them
(refer to Paragraph 4.11, Replacement).
CAUTION

When installing the new motor, make sure there
are no loose wires between the motor mounting
plate and tape deck.

Position the motor on the rear of the tape deck so
that the B1P1 cable extends from the right. Secure
the motor with the four mounting screws.

. Attach connector BIP1 to J3 on the power amplifier
module.

. Attach connector W3P5 to the tach sensor pins as
shown in Figure 4-11.
Install the tach cover and secure it with the four
mounting SCrews.

. Install the drive cover and return the tape deck to the
operating position.

Perform the replacement procedure for the supply
reel hub assembly (Paragraph 4.9).

REMOVAL AND REPLACEMENT

WIRES OF

CONNECTOR SHOWN
AWAY FROM
FACING
REEL MOTOR

0.030 £.005"

TACH
WHEEL

=N
w

0.150 +0.01"

TACH
SENSOR

MOUNTING
PLATE

MOUNTING
PLATE
MA-0080-83

Figure 4-11

Tachometer Wheel and Sensor Alignment

Verification Check

1. With the tape threaded but not loaded, execute operator diagnostic test O1.

4.11

SUPPLY MOTOR TACHOMETER AND
SENSOR

Removal

Place the tape deck in the maintenance position
(Paragraph 4.1).

Remove the four mounting screws and the tachometer cover from the supply motor (Figure 4-10).

Remove connector W3P5 from the sensor pins.

Remove the mounting screws and the sensor from the
mounting plate.

Loosen the two set screws securing the tachometer to
the motor shaft and remove the tachometer.

Replacement

Insert the tachometer wheel on the motor shaft. Posi-

tion the tachometer for a 0.030 + 0.005 inch clearance between the tachometer and the sensor
mounting plate (Figure 4-11).

REMOVAL AND REPLACEMENT

Install the sensor on the mounting plate and position

for a clearance of 0.150 = 0.01 inch between the

sensor and the tachometer. Tighten the sensor mounting screw.
Attach connector W3P5 to the sensor pins.

Install the tachometer cover and secure with the four
mounting SCrews.

Return the tape deck to the operating position.

Verification Check
1.

With the tape threaded but not loaded, execute operator diagnostic test Ol.

4.12

AIR BEARING SENSORS

Removal

NOTE
Replacement parts for the air bearing assembly

are contained in the refurbishing kit (PN 2924359). This kit contains upper and lower
spring guides, a sensor, and small and large Orings. If you are replacing the sensor, Digital
recommends that you also replace the upper and

lower spring guides and large and small O-rings.
Perform steps 1 through 8 of Paragraph 4.21 (Servo
Control Module, Removal section).
2.

Remove connector P1 from the sensor pins.
To gain access to the screws holding the air bearing,

remove the screws holding the logic cage (Paragraph
4.20) and move the cage enough to access the air
bearing mounting screws. Do not remove the tie
wraps holding the cables to the cage.
Remove the mounting screws and washers (Figure
4-12) from the air bearing assembly (the tape path
cover on the top of the tape deck will hold the air
bearings in place).

CAUTION
Be careful not to snag or chafe the control panel
cable or any other cable when positioning the
tape deck.

REMOVAL AND REPLACEMENT

PIN 4

LABEL

LARGE "“O" RING
INTO AIR BEARING

SMALL “O"” RING

INTO SENSOR

SENSOR CABLE
CONNECTOR

SENSOR
MOUNTING
SCREWS

SENSOR

PIN 4
MA-0466-82

Figure 4-12

Air Bearing Sensors

Return the tape deck to the operating position.

Remove the tape path cover and lift the air bearings

away from the tape deck.
7.

Remove the O-ring from the air bearing housing.

8. Remove the two socket head screws and washers
securing the sensor to the rear of the air bearing.
Remove the sensor and the small O-ring from the air
bearing housing.
\O

. Replace the upper and lower spring guides as
described in Paragraph 4.13.

Replacement

1.
2.

Insert a new small O-ring in the opening at the rear of
the sensor.
Position the sensor on the air bearing so that the

connector pins are positioned towards the outside of
the air bearing. Secure the sensor with the mounting
screws and washers.

REMOVAL AND REPLACEMENT

3. Insert a large O-ring into the opening at the rear of
the air bearing housing.

4. Place the air bearing assembly onto the tape deck
using the locating pin for positioning. Install the tape
path covers to hold the air bearings in position.
5. Place the tape deck in the tilted maintenance position. Secure the air bearings with the mounting
screws and washers.

6. Replace the screws holding the logic cage (Paragraph
4.20).

7. Attach connector P1 to the sensor pins. Refer to
Figure 4-12 for pin orientation.

8. Perform steps 4 through 10 of Paragraph 4.21 (Servo
Control Module, Replacement section).
Verification Check

1. With the tape threaded but not loaded, execute operator diagnostic test O1.

4.13

AIR BEARING SPRING GUIDES

Removal
NOTE

Replacement parts for the air bearing assembly
are contained in the refurbishing kit (PN 2924359). This kit contains an upper and lower
spring guide, a sensor, and a small and large Oring. If you are replacing a spring guide, Digital
recommends that you replace both upper and
lower guides.

1. Remove the tape path and magnetic head covers
from the tape deck.

2. Remove the two phillips head screws securing the
rear spring guide and guard to the bearing housing
(Figure 4-13).

3. Remove the spring guard and guide from the
housing.

4. Repeat steps 2 and 3 to remove the front spring
|
|
guide.

REMOVAL AND REPLACEMENT

BEARING
HOUSING

SPRING

/44

GUIDE

SPRING

GUARD

NOTE

THE

FRONT AND REAR SPRING GUIDES

ARE NOT INTERCHANGEABLE.
MA-0459-82

Figure 4-13

Air Bearing Spring Guide

Replacement

Place the new rear spring guide (PN 77004255) and
guard into the bearing housing. Use the holes for the
mounting screws to align both parts to the housing.

Secure the guide with the two phillips head screws.

Repeat steps 1 and 2 using the new front spring guide
(PN 77004254) to replace the used guide.

Install the tape path and magnetic head covers on the
tape deck.

Verification Checks

Thread but do not load the tape. Execute operator

diagnostic test O1.
2.

Visually check the tape for tape edge damage.

REMOVAL AND REPLACEMENT

4.14

PNEUMATIC PUMP ASSEMBLY

Removal

1. Place the tape deck in the maintenance position
(Paragraph 4.1).

2. Detach the two pneumatic tubes from the filter box
assembly (Figure 4-14).

MOUNTING

SCREWS (4)

TUBING TO

FILTER BOX\
—
TUBING TO o/
TAPE DECK /

PNEUMATIC
PUMP

CONNECTOR
MA.-0496-84

Figure 4-14

Pneumatic Pump Assembly

REMOVAL AND REPLACEMENT

Remove the drive cover to access the pneumatic
pump (Paragraph 4.2).

4. Remove connector W4P2 from the power supply.
5. Remove the pneumatic tube connected from the tape
deck nipple to the pneumatic pump.
NOTE

Detach any wiring that may interfere with
removal of the pneumatic pump assembly.

Remove the four mounting screws and washers securing the pneumatic assembly to the tape deck. Carefully withdraw the assembly from the transport.
Replacement
1.

Position the pneumatic pump assembly to the rear of

the tape deck and secure it with the mounting screws
and washers.

Attach the pneumatic tubes from the compressor to
the tape deck nipple.

Attach connector W4P2 to the power supply. Attach
any wiring that was disconnected during the removal
procedure.

. Install the drive cover and attach the two pneumatic
tubes to the filter box assembly.

NOTE

Make sure that the in and out tubes are
attached to the proper nipples (Figure 4-14).

Return the tape deck to the operating position.
Verification Check
1.

With the tape threaded but not loaded, execute operator diagnostic test O1.

REMOVAL AND REPLACEMENT

4.15 PRESSURE REGULATOR AND FILTER
ASSEMBLY

Removal

CAUTION

Filter replacement should only be performed
when necessary. It should not be replaced on a
PM schedule. Air pressure could be lost through
the seals when removing and replacing the filter
box.

NOTE

If you are only replacing the pressure regulator,
perform Removal steps 1 and 2, Replacement
steps 4 and 5, and the Verification Check. If the
filter is being replaced, perform the entire
Removal, Replacement, and Verification Check
procedures.

1. Place the tape deck in the maintenance position (Paragraph 4.1).

2. Remove the pressure regulator by unscrewing the
regulator from the filter box assembly (Figure 4-15).
3. Remove the two pneumatic tubes from the in and out
nipples on the filter box.

4. Remove the four mounting screws securing the filter
box and remove the filter box from the tape deck.
5. Remove the filter from the filter box.
Replacement

1. Insert the filter into the filter box.

Secure the filter box to the tape deck with the four
“mounting screws. Check the seals for air leaks.

. Install the two pneumatic tubes on the in and out
nipples.

. Screw the pressure regulator clockwise onto the filter
box assembly.
5.

Return the tape deck to the operating position.

Verification Check
1.

With the tape threaded but not loaded, execute operator diagnostic test Ol.

REMOVAL AND REPLACEMENT

BOX

—%

22
N,

—

PRESSURE

REGULATOR

N ‘\‘"\

[

(
?

MA-0493-84

Figure 4-15

416

Filter Box Assembly

MAGNETIC HEAD ASSEMBLY

Remov.al
1.

Remove the head covers from the tape deck.

From the top of the transport, detach read head con-

nector W6P1, write head connector WS5P1, and erase

head wires P3/P4 from the magnetic head (Figure
4-16).
NOTE
Before removing the magnetic head, tape a piece

of soft material across the recording surface.
3.

Perform steps 1 through 6 of Paragraph 4.21 (Servo

Control Module, Removal section).

REMOVAL AND REPLACEMENT
WHITE TO FRONT
P3/P4
BLACK TO BACK

W5P1———>L_

ERASE

WRITE

W6P1
READ

ASSEMBLY SCREWS

MAGNETIC HEAD
CONNECTORS

(DO NOT LOOSEN )

MAGNETIC
HEAD

MOUNTING
SCREWS (4)

MA-0497-84

Figure 4-16

Magnetic Head Assembly

4. From the rear of the tape deck, remove the read,
write, and erase connectors from the magnetic head.
CAUTION

Refer to Figure 4-16 for the location of the
head mounting screws. Do not loosen the head
assembly screws. Otherwise, you must replace
the entire head with a new assembly.

5. Loosen the four head mounting screws. Hold the
magnetic head against the tape deck while you
remove the four mounting screws, lockwashers, and
flatwashers.

6. Carefully withdraw the head from the tape deck.

REMOVAL AND REPLACEMENT

Replacement

NOTE
Before you install the magnetic head, make sure
the recording surface is protected with soft
material.

. Pull the magnetic head from inside through the tape
deck and position it with the mounting surface on the
guide pins.

While holding the head in place, insert the
flatwashers, lockwashers, and mounting screws.
Tighten the four mounting screws.

Pull the read and write/erase cables through the tape
deck.

From the top of the tape deck, attach the read, write,
and erase connectors to the magnetic head (Figure
4-16). Remove the recording surface covering.
Perform steps 6 through 10 of Paragraph 4.21 (Servo
Control Module, Replacement procedure).
Install the head covers on the tape deck.

Proceed with the following verification checks.
Verification Checks

Clean the magnetic head recording surface with a
soft lint-free cloth moistened with tape transport
cleaner. Wipe the recording surface in the same
direction as the tape motion.

2. Load a 3M777, or equivalent, write enabled tape.
. Move jumper W1 at location D23 on the servo control module (Figure 4-27) to the 1-2 position.
Execute Field Service test 64. (It sets write current
values.)
.

Execute Field Service test 31. The test should complete with the display 00.
Return jumper W1 at location D23 from the 1-2
position to the 2-3 position before you power down
the unit.

With the tape threaded but not loaded, execute operator test O1. If the test is successful, it will terminate
with the display 00. If the test is unsuccessful, refer
the display number to the corresponding fault code in
the TU81/TA81 Pathfinder.

REMOVAL AND REPLACEMENT

4.17

CONTROL PANEL ASSEMBLY

1. Open the front door of the TU8I cabinet.

Disconnect the W8P1, W16P2, and W13J1 cable
connectors from the control panel (Figure 4-17).
Remove the four mounting screws from the control
panel bracket and the ground strap connector from
the door assembly.

. Move the bracket away from the door assembly
(fault switch and +5 V cable still attached).
. Remove the push-in clips securing the control panel
to the mounting bracket.

Remove the connector from the indicator panel. The
control panel can now be removed.
Replacement
1.

Reconnect the small connector to the indicator panel.
Align the mounting holes in the control panel with
the holes in the bracket and secure the control panel
with the four push-in clips (Figure 4-17).

CONTROL

W13J1

MOUNTING

SCREWS
(4)

MOUNTING

BRACKET
MA -0035-83A

Figure 4-17

Control Panel Assembly

REMOVAL AND REPLACEMENT

Place the control panel and bracket in position on the
door assembly and install the four mounting screws.
Attach the ground strap to the door assembly.
Attach the W8P1, W16P2, and W13J1 cable connectors to the control panel assembly.

Close the front door.

Verification Check

Thread the tape but do not load it and run operator
diagnostic test 01.
4.18

COOLING FAN ASSEMBLY

Removal
.

Place

the

tape

deck

the

maintenance

posi-

tion (Paragraph 4.1).

Remove the drive cover (Paragraph 4.2). Detach the
cooling fan connector from receptacle J3 on the power supply (Figure 4-18).

Remove the four hex nuts and washers and withdraw
the fan assembly from the mounting studs.

COOLING FAN
MA -0657-84

Figure 4-18

Cooling Fan Assembly

100

REMOVAL AND REPLACEMENT

Replacement

1. Attach the cooling fan connector to receptacle J3 on
the power supply.

2. Place the cooling fan in position on the mounting
studs and secure it with the four nuts and washers.
3. Replace the drive cover (Paragraph 4.2).
Verification Check

1. Power the transport on and check for air flow from
the fan.

4.19

POWER SUPPLY

Removal

1. Discohnect the power cable (Figure 1-7) from the
power supply.

2. Tilt the tape deck into
tion (Paragraph 4.1).

the

maintenance posi-

3. Remove the cooling fan assembly (Paragraph 4.18).

4. Detach all the connectors and cables from the power
supply (Figure 4-19).

5. Place the tape deck in the operating (horizontal)
position.

6. Open the rear door of the cabinet.

7. Remove the frame stabilizing bar by removing the
mounting screws (Figure 4-20).
NOTE

The power supply is attached to the tape deck
by four screws. The two screws on the left are
located in slots so that you can slide the power
supply out from under these screws for removal.
8. Loosen but do not remove the two mounting screws
on the left side of the power supply.
9. Remove the two mounting screws on the right side of
the power supply while you support the power supply
from the bottom.

10. Slide the power supply out of the slots on the left and
carefully remove it from the cabinet.

NOTE

The power supply weighs approximately 4.1 kg
(9 Ib). Use caution when you lift it.

REMOVAL AND REPLACEMENT

101

TO TB—1 VOLTAGE
TERMINAL STRIP

B4P1 TO

COOLING
FAN

W4P2 TO

W2P2 TO

PNEUMATIC

SERVO CONTROL

PUMP

MODULE (J7)

MA-0494-84

Figure 4-19

Power Supply

LOOSEN BUT
DO NOT

REMOVE

2 SCREWS

FROM SLOTS///

REMOVE

2 SCREWS

(]

(

STABILIZING

‘ / BAR

POWER / '\“'
le

SUPPLY

N\~

\COOLING
FAN

CABINET REAR
s

MA-0078-83

Figure 4-20

Power Supply (Rear Cabinet View)

102

REMOVAL AND REPLACEMENT

Replacement
NOTE
If you are installing a new power supply, remove
the power supply cover and observe the position
of the voltage select card (Figure 4-21). The
position of this card must correspond to the

input voltage defined on the transport’s identification plate. The ends of the card are stenciled
with “120V” and “220V” and two indicating
arrows. Make sure the card is conmected to

match the input voltage.

You can disconnect the card, turn it upside
down, and reconnect it to the main power supply
module if required.
1.

From the rear of the transport, position the mounting

slots on the left side of the power supply under the
two loosened mounting screws.
2.

Insert and tighten the two mounting screws on the
right side of the power supply.

Tighten the two mounting screws on the left side.

Install the frame stabilizing bar and secure it with the

Tilt the tape deck into the maintenance position.

Attach the cables to the power supply as follows.

mounting screws. Close the rear cabinet door.

Power Supply
Connector

Cable

W4P2 pneumatic pump

B4P1 cooling fan

W7P1 TBI terminal block

W2P2 servo control module

J10

TB1 terminal block

Install the cooling fan assembly (Paragraph 4.18).

Place the tape deck in the operating position.

Connect the power cable to the power supply.

Verification Check

DC Voltage Check — Connect the ground lead of a
digital voltmeter to pin 5 of power terminal strip TB1
(Figure 4-22). Connect the other meter lead to the
TB1 points shown in Figure 4-22 to test all dc
voltages.

103

REMOVAL AND REPLACEMENT
N

- =

< T sov

550 v

250V

SS 1L
1/8A
H——‘ -

e
-

—— 250V

2
N

< 2

=
nfl
—

N
o

MA -0455-82A

Figure 4-21

Voltage Select Card

RED—BROWN

+25V

BLANK

—_

BLACK

GND

BLACK

GND

BLACK

GND

RED/WHITE

+15V

RED/WHITE

+15V

BLUE/WHITE

—15V

RED

+5V

RED

+5V

BLUE

—6vV

BLANK

——

MA -0490-84

Figure 4-22

Power Terminal Strip TB1

104

REMOVAL AND REPLACEMENT

420 WRITE DRIVER MODULE
NOTE

To service this module, you must separate it
from the logic cage and move it to the maintenance position (Figure 4-23). Refer to Paragraph 1.8.1 to check on the shipping and safety
brackets you have to remove when working with
this cage.

CAUTION

Be careful not to place too much stress on the

wires or modules when removing the connectors.
Removal

Place the tape deck in the maintenance position (Par-

agraph 4.1).

. Remove connectors W5P2, W7P6, and W12P1 (Figure 4-24) from the write driver module.
Pull the retaining latch at the top of the logic cage
toward you to release it from the operating to the
maintenance position.

While removing connectors W7P4 and W7P5, slide
the modules to the maintenance position (Figure
4-23).

Remove the two standoff screws that hold the write
driver module to the read amplifier module (Figure
4-25).

Slide the write driver module out of the two plastic
clips mounted on the read amplifier module.
Replacement
1.

Slide the write driver module into the two plastic clips
mounted on the read amplifier module (Figure 4-25).
Mount the write driver module on the standoffs using
the two standoff screws.

. While sliding the modules to the right (to the operating position as in Figure 4-23), replace connectors
W7PS5 and W7P4 on top of the read amplifier
module.

Engage the retaining latch at the top of the cage
(return it to the operating position.

. Replace connectors W12P1, W7P6, and W5P2 on
the write driver module.
. Place the tape deck in the operating position.

REMOVAL AND REPLACEMENT

POSITION

F—o

OPERATING
POSITION

‘
'&’

SHIPPING

/ POSITION

MAINTENANCE

e B E@

BRACKET\

OPERATING
POSITION

HOLDING
y

=(83

=
1=
i

BRACKET

MAINTENANCE

(SLIDE—OUT)
POSITION

l/@%
MA-0411-84

Figure 4-23

Logic Cage for Write Driver, Read
Amplifier, and Servo Control Modules

105

106

REMOVAL AND REPLACEMENT

W7P6

W5P2 —&

W12P1 —s|4

HOLES TO CLEAR

//")

CONNECTOR LEVERS

ON READ BOARD

SCREWS(2)
MA -0499-84

SHR-0312-85

Figure 4-24 Write Driver Module

Verification Check

Load a 3M777, or equivalent, write enabled tape.
Execute Field Service test 64.
Execute Field Service test 31.

With the tape threaded but not loaded, execute oper-

ator test O1. If the test is successful, it will terminate

with the display 00. If the test is unsuccessful, perform troubleshooting procedures 1001 through 1003
as explained in the TUS81/TA81 Pathfinder
(EK-TUAS81-SV).

ALLLARLLAAMLANY o MW O

REMOVAL AND REPLACEMENT

107

J9 (SERVO

CONTROL

MODULE)

W12P3

PLASTIC

J8 (SERVO

CONTROL

MODULE)

AWIMAAMAAMAL o MWWV

CLIPS

MA.0714-84

SHR-0313-85

Figure 4-25

Read Amplifier Module

108

REMOVAL AND REPLACEMENT

421

READ AMPLIFIER MODULE
NOTES

1. To service this module, you must separate it
from the logic cage and move it to the maintenance position (Figure 4-23). Refer to Paragraph 1.8.1 to check on the shipping and safety
brackets you have to remove when working with
this cage.

2. Remove the write driver and read amplifier
modules together and separate them after
removal (Figure 4-26).
CAUTION

Be careful not to place too much stress on the

wires or modules when removing the connectors.

1. TOP THUMBSCREW (TOP AND BOTTOM HINGES) BACK OUT
7O REMOVE READ AMPLIFIER MODULE.

2. BOTTOM THUMBSCREW (TOP AND BOTTOM HINGES) BACK
OUT TO REMOVE SERVO CONTROL MODULE.

BRACKET/
SPACER BLOCK

RETAINING 7

BAR

LATCH

OPERATING
POSITION

A =
==

MAINTENANCE
POSITION

READ
—

AMPLIFIER

LOOSEN THUMB WHEELS

WRITE —®
DRIVER

LOOSEN

{ TOP AND BOTTOM}

THUMB SCREWS

TO SWING MODULES OPEN

TO SEPARATE
MODULES ( AT

J2/J9 AND J3/J8)
LOGIC

“ CARD
CAGE

SERVO CONTROL

S
MA .0483-84

Figure 4-26

Removing Write Driver, Read

Amplifier, and Servo Control Modules

REMOVAL AND REPLACEMENT

109

Removal

Place the tape deck in the maintenance position (Par-

agraph 4.1).

Remove connectors W5P2 and W7P6 (Figure 4-24)
from the write driver module.

. Remove connector W6P2 from the read amplifier
module (Figure 4-25).

Loosen the thumb wheels on the logic cage to separate the modules from it (Figure 4-26).

Pull the retaining latch at the top of the logic cage
toward you to release it from the operating to the
maintenance position.

While removing connectors W7P4 and W7P5, slide
the read amplifier and servo control modules to the
maintenance position (Figure 4-23).
. Loosen the upper thumbscrew 6 or 8 turns at the top
and bottom brackets/spacer blocks (Figure 4-26).
Remove the plastic board clips at the top and bottom
of the modules. Loosen the thumbscrews on the read
amplifier module at J2/J9 and J3/J8. Avoid excessive stress on the modules by loosening the thumbscrews alternately and separating J2 from J9 and J3
from J8 as the screws are loosened.

Slide the read amplifier module with the write driver
module out of the brackets and remove them from
the cabinet.
10.

Remove connector W12P1 from the write driver
module (Figure 4-24).

11.

Separate the write driver module from the read
amplifier module as described in Paragraph 4.20.

Remove connectors W12P2 and W12P3.

12.

Replacement
1.

Install connectors W12P2 and W12P3 on the new
module.

. Mount the write driver module as describedin Paragraph 4.20..

. Replace connector W12P1 on the write driver
module.

Slide the read amplifier module with the write driver
module into the top and bottom brackets.

110

REMOVAL AND REPLACEMENT

5. Align connector J2 with J9 and connector J3 with J3
(Figure 4-26). Press the connectors together while
tightening the thumbscrews alternately. Replace the
clips on the top and bottom of the modules.

6. Tighten the upper and lower thumbscrews on the top
and bottom brackets.

7. While sliding the modules to the right (to the operating position as in Figure 4-23), replace connectors
W7P5 and W7P4 on top of the read amplifier
module.

8. Tighten the upper and lower thumbscrews holding
the servo control module to the logic cage and engage
the retaining latch at the top of the cage (return it to
the operating position).

9. Replace connector W6P2 on the read amplifier
module.

10. Replace connectors W5P2 and W7P6 on the write
driver module.

11. Place the tape deck in the operating position.
Verification Check

1. Load a 3M777, or equivalent, write enabled tape.
2. Move jumper W1 at location D23 on the servo control module to the 1-2 position (Figure 4-27).
3. Execute Field Service test 31. If the test is successful,
it will terminate with the display 00. If the test is
unsuccessful, refer the display number to the test
description for test 31 in the TU81/TA81 Pathfinder (EK-TUA81-SV).

4. After the test is successfully completed (display 00),
return jumper W1 from the 1-2 position to the 2-3
position before powering down.

5. With the tape threaded but not loaded, execute operator test O1. If the test is successful, it will terminate
with the display 00. If the test is unsuccessful, perform troubleshooting procedures 1001 through 1003
as explained in the TU81/TA81 Pathfinder
(EK-TUAS81-SV).

REMOVAL AND REPLACEMENT

J2 READ

W7P4

AMPLIFIER

SERVO

MODULE
I

CONTROL
MODULE

)

JI0 R

123

J3 [Re— WOP2

4 Be—y1p2

{

— \W10P1

+—w8P1

J3READ

AMPLIFIER
MODU LE

Figure 4-27

MA-0492-84

Servo Control Module

111

112

REMOVAL AND REPLACEMENT

4.22

SERVO CONTROL MODULE
NOTE

Remove the servo control, read amplifier, and
write driver modules together. First move all
modules to the maintenance position as in Figure 4-23. Remove all the modules from the logic

cage (Figure 4-26). Then separate the servo control module from the other modules.
CAUTION

Be careful not to place too much stress on the
wires or modules when removing the connectors.

Removal
1.

Place the tape deck in the tilted maintenance position
(Paragraph 4.1).

Remove connectors W5P2 and W7P6 from the write
driver module (Figure 4-24).

Remove connector W6P2 from the read amplifier
module (Figure 4-25).

. Loosen the upper and lower thumbscrews holding the
servo control module to the logic cage (Figure 4-26).
Release (pull toward yourself) the retaining latch on
the top of the logic cage to the maintenance position.
While removing connectors W7P4 and WT7P5, slide
the servo control and read amplifier modules to the
maintenance position (Figure 4-23).

Remove connectors W3P8, W10P1, W8PI, and
W2P1 (Figure 4-27) from the servo control module.
Iabel and remove connectors W9P2 and W1P2.
Remove the retaining bar from the logic cage (Figure
4-26) and remove the modules from the cabinet.
At the top and bottom brackets, loosen the lower
thumbscrews 6 to 8 turns (Figure 4-26).

Remove the top and bottom board clips. Loosen the
thumbscrews at edge connectors J2/J9 and J3/J8
(Figure 4-26). Avoid excessive stress on the modules
by loosening the screws alternately and separating J2
from J9 and J3 from J8 as the screws are loosened.
the top and
10. Slide the servo control module out of
bottom brackets.

REMOVAL AND REPLACEMENT

113

Replacement

Make sure that jumper W1 is in the 2-3 position on
the replacement module. Slide the servo control module into the top and bottom brackets.

Align J2 with J9 and J3 with J8. Press the connectors

together while alternately tightening the thumbscrews. Replace the top and bottom board clips.

. Tighten the lower thumbscrews at the top and bottom
brackets.

Place the modules in the cabinet in the maintenance
position (Figure 4-23). Replace the retaining bar.

Replace connectors W2P1, W8P1, W10P1, WIP2,
WOIP2, and W3P8 on the servo control module.
. Swing the modules to the right (to the operating position) while replacing connectors W7P4 and W7P5 on
the top of the servo control and read amplifier
modules.

. Tighten the thumbscrews on the servo control module
and engage (return to the operating position) the
retaining latch.

Replace connector W6P2 on the read amplifier
module.

. Replace connectors W5P2 and W7P6 on the write
driver module.
10.

Return the tape deck to the operating position.

Verification Check
1.

Move jumper W1 at location D23 on the servo control module to the 1-2 position.

With the tape not threaded, execute Field Service test
37. If the test is successful, it will terminate with the
display 00. If the test is unsuccessful, refer the display number to the test description for Field Service
test 37 in the TU81/TA81 Pathfinder (EK-TUASISV).

Execute Field Service test 49.

. Execute Field Service test 64.
. Execute Field Service test 31. If the test is successful,
it will terminate with the display 00. If the test is
unsuccessful, refer the display number to the test
description for Field Service test 31 in the
TUS81/TA81 Pathfinder (EK-TUA81-SV).

114

REMOVAL AND REPLACEMENT

6. After the test is successfully completed (display 00),
return jumper W1 from the 1-2 position to the 2-3
position before powering down.

. Install and tighten the top and bottom thumbscrews
to secure the modules to the logic cage.

With the tape threaded but not loaded, execute operator test O1. If the test is successful, it will terminate
with the display 00. If the test is unsuccessful, perform troubleshooting procedures 1001 through 1003

explained

the

TUS81/TA81

(EK-TUARB1-SV).
4.23

Pathfinder

FORMATTER READ MODULE

Removal
1.

Loosen the top and bottom logic cage lockscrews and
slide the cage out until the top and bottom guards
engage (Figure 4-28).
Loosen the two thumbscrews (Figure 4-28) on the
formatter read module and separate the formatter

read module from the formatter write module. Avoid
excessive stress on the modules by loosening the
thumbscrews alternately and separating the modules
as the screws are loosened.
Loosen the upper screws of each hinge 6 to 8§ turns
(Figure 4-28). Loosen the lower screws 2 turns. (Do
not remove any of the screws). Hold the module in

place while loosening the screws.
.

Remove the formatter read module from the logic
cage.

Replacement
1.

Insert the module into the top and bottom hinge slots
of the logic cage. Make sure the module is fully
inserted into the hinge slot and W7P8 rear connector.

Attach the outside pin connectors of the formatter
read and formatter write modules and secure them

Tighten the upper and lower screw of the top and
bottom hinges to lock the formatter read module into

with the two thumbscrews.

position. Make sure all four hinge screws are snug.

.- Release the upper and lower guards and slide the cage
into the frame. Tighten the cage lockscrews.

115

REMOVAL AND REPLACEMENT

(@ PusHTO RELEASE

(1) RELEASE PLASTIC SNAP

TOP AND BOTTOM

(@ PUSH IN THEN RELEASE METAL
SNAP TOP AND BOTTOM

(3 RESUME PUSH

\
(1) BACK OUT SCREW TO REMOVE
INTERFACE MODULE

(2) BACK OUT SCREW (TOP AND
BOTTOM ) TO REMOVE

FORMATTER READ MODULE

BACK OUT SCREW (TOP AND
BOTTOM) TO REMOVE

FORMATTER WRITE MODULE

TO REINSERT MODULE SET

277

Qond

(4) TAB MUST BE DEPRESSED

LOOSEN SCREW

(TOP AND BOTTOM)
TO EXTEND

MODULE SET

WRITE MODULE/'\ +
FORMATTER

)

FORMATTER

READ MODULE

LOOSEN SCREW (TOP
AND BOTTOM) TO

SEPARATE MODULES

L/ D
'
:

INTERFACE

//MODU,_E

LOOSEN SCREW (TOP

AND BOTTOM) TO
SWING INTERFACE
MODULE OPEN

MA -0495-84

Figure 4-28

Logic Cage for Formatter Read, Format-

ter Write, and Interface Modules

116

REMOVAL AND REPLACEMENT

Verification Check
1.

Thread the tape but do not load it and execute operator test O1. If the test is successful, it will terminate
with the display 00. If the test is unsuccessful, per-

form troubleshooting procedures 1001 through 1003
explained in the TUS81/TA81 Pathfinder
(EK-TUAS81-SV).
as

4.24

FORMATTER WRITE MODULE

Removal
1.

Loosen the logic cage lockscrews and slide the cage
out until the top and bottom guards engage (Figure

4-28).
2.

Remove the top and bottom thumbscrews securing
the interface module to the formatter write module.

Remove connectors W10P2 and W11P from the
formatter write module (Figure 4-29) and remove
power supply connector W7P8 at the rear of the

Loosen the two thumbscrews on the formatter read

module.
module (Figure 4-28) and separate the formatter read

module from the formatter write module. Avoid
excessive stress on the modules by loosening the
thumbscrews alternately and separating the modules

as the screws are loosened.
5.

Loosen the lower screws of each hinge 6 to 8 turns
(Figure 4-28). Hold the module in place while loosen-

ing the screws.
6.

Remove the formatter write module from the cage.

Replacement

NOTE
Before installing the new module, make sure
that the jumper blocks (W1, W2, W3) at mod-

ule locations A1 and B1 are in the same positions as on the replaced module.

Insert the module into the top and bottom hinge slots

of the logic cage. Make sure that the module is fully
inserted into the hinge slot.
2.

Attach the edge pin connectors of the formatter read

and formatter write modules and secure them with
the two thumbscrews.

REMOVAL AND REPLACEMENT

117

FORMATTER
READ

~
)

———————0

[

W/71/ AT 1117/4 i

MODULE

JSX

321

:
THIIIHIITII S IHTHIEHTEITY

FORMATTER

WRITE
MODULE

Figure 4-29

MA -0555-84

Formatter Write Module

. Tighten the lower screw of the top and bottom hinges
to lock the formatter write module into position.
Make sure that all four hinge screws are snug.

. Attach connector W10P2 to J5, WI11P to J4, and
power connector W7P8 to the module.
. Secure the formatter write module to the formatter
read and interface modules using the thumbscrews as
shown in Figure 4-28.

. Release the upper and lower guards and slide the
modules into the cage. Secure the modules with the
logic cage lockscrews.

118

REMOVAL AND REPLACEMENT

Verification Check
1.

With the tape threaded but not loaded, execute operator test 01. If the test is successful, it will terminate
with the display 00. If the test is unsuccessful, perform troubleshooting procedures 1001 through 1003

explained

the

TU81/TA8I1

Pathfinder

(EK-TUAS81-SV).
4.25

TMSCP

INTERFACE

CONTROLLER

MODULE
Removal

Loosen the top and bottom logic cage lockscrews and

slide the cage out until the upper and lower guards

engage (Figure 4-28).
2.

Release the upper and lower thumbscrews securing
the TMSCP interface module to the formatter write

Remove connectors

module.
W17P1 (J4), WI15P1 (J5),
WI11P, and W18 (I/O cable) from the interface mod-

ule (Figure 4-30).
4.

Release the top and bottom screws from the brackets
(Figure 4-28) and free the module from rear connector W7P9. Remove the module from the cage.

NOTE
Before installing the new TMSCP interface
controller module, make sure that the baud rate
jumpers are in the same positions as on the
replaced module.

Replacement
1.

Attach rear connector W7P9 to the TMSCP interface module. Insert and secure the interface module

in the upper and lower brackets (Figure 4-28).
2.

Install the cable connectors as follows (Figure 4-30).
W7P9 to J1

W18 to J2
WI1P to Al

W17P1 to J4

WI15P1 to J5

REMOVAL AND REPLACEMENT

119

(FORMATTER
WRITE

CONNECTOR)

BAUD —

SELECTION

) .
n

)

N\\

éawemaafi

JUMPERS

w18

(SYSTEM 1/0O

CONNECTOR)

|
MA-0356-84

Figure 4-30

TMSCP Interface Controller Module

Tighten the upper and lower thumbscrews to secure

the interface module to the formatter write module.
4.

Release the upper and lower guards and slide the cage

into the frame. Tighten the top and bottom cage
lockscrews.

120

REMOVAL AND REPLACEMENT

Verification Check
1.

Applying dc power to the drive will result in the
execution of the internal interface health check. If
the check is successful, the unit number is displayed
on the operator panel. If the test is unsuccessful,
perform troubleshooting procedures

1001

through

1003 as explained in the TU81/TA81 Pathfinder

(EK-TUAS81-SV).
4.26

POWER AMPLIFIER MODULE

Removal
.

Place the tape deck in the maintenance position (Par-

agraph 4.1).
2.

Remove the drive cover (Paragraph 4.2).

Remove the following connectors from the power

amplifier module (Figure 4-31).

B3P1 from J1
W3P7 from J2

BI1P1 from J3
W7TP7 from J4

C1P1 from J5
.

Release the three quick disconnect tabs along the
outside edge of the module to remove the module
from the mounting assembly.

Remove the module.

Replacement
1.

Insert the power amplifier module into the mounting
assembly. The inside of the mounting assembly has
metal slots to receive the module.

Secure the module by pressing it onto the tabs along
the outside edge.
Install the connectors as follows (Figure 4-31).

B3PI to J1
W3P7 to J2

BIP1 to J3
W7P7 to J4

C1P1 to J5

REMOVAL AND REPLACEMENT

121

MOUNTING SCREWS (3)

CIPI

CAPACITOR

/ ASSY
J5

QQg)

,
.

B3PI TAKE—UP
MOTOR

W7P7 POWER

éjo

SUPPLY

W3P7

¥ SERVO

MODULE

MOTOR

BIPI SUPPLY

Figure 4-31

Power Amplifier Module

Install the drive cover (Paragraph 4.2).

Place the tape deck in the operating position.

Verification Check

1. With the tape threaded but not loaded, execute oper-

ator test O1. If the test is successful, it will terminate
with the display 00. If the test is unsuccessful, perform troubleshooting procedures 1001 through 1003
as explained in the TU81/TA81 Pathfinder (EKTUAS81-SV).

122

REMOVAL AND REPLACEMENT

4.27

CAPACITOR ASSEMBLY

Removal

Place the tape deck in the maintenance position (Paragraph 4.1).

Remove the drive cover (Paragraph 4.2).

Detach capacitor connector CI1P1 from J5 of the
power amplifier module (Figure 4-31).
CAUTION

Do not remove the protective terminal caps
located on top of the capacitor during the
removal or replacement procedures.

Remove the three mounting screws from the capacitor assembly (Figure 4-32). Remove the capacitor
assembly.

ASSEMBLY

D
Ca
TM,

MOUNTING

SCREWS (3)

ra ¥},

\/\ T~

TO POWER AMP

MODULE (J5)

]

.m ¥

MA -0556-84

Figure 4-32

Capacitor Assembly

REMOVAL AND REPLACEMENT

123

Replacement

Mount the replacement capacitor assembly as shown
in Figure 4-32 and secure it with the three mounting
SCIews.

Attach capacitor connector C1P1 to J5 on the power

amplifier module.
3.

Install the drive cover (Paragraph 4.2).

Verification Check
1.

Thread but do not load the tape. Run diagnostic test

01 (and, if necessary, 02).

A SENSE BYTES

124

APPENDICES

125

APPENDICES
126

ASTY

9poo J[nej dnsouderg

9SI9A3Y 9IM 45d oD Juor]de3 S/Sspour 4! 69CY
ISUIS [IDSV
APPENDICES
127

[pOa1o3aU0lDod

128

APPENDICES

1LTY

TROUBLESHOOTING
FLOWCHART
J

—

POWER OFF

AND ON

(WAIT 15 SECONDS)

CKT BREAKER
REMAIN ON ?

LOGIC ON
INDICATOR ON ?

VALID
FAULT CODE

DISPLAYED ?

EXIT TO TUB1/TABI

CTLR

PATHFINDER, FAULT

FAULT ()N’/

PERFORM

CODE SECTION.

POWER

PERFORM FAULT

PROCEDURE 1001

RUN TEST01

RUN TEST 01

J
./

CTLR FAULTON\?
'

REPLACE TMSCP
OR STI MODULE

;

]

—

]

L RUN TESTO1

POWER TUB1 TA81
OFF DISCONNECT
INTERFACE CABLE.
POWER UNIT ON.

CODE PROCEDURE

PROBLEM IS IN

SUBSYSTEM.

DRIVE INDICATIONS

ARE NORMAL

|
CONTINUE WITH HOST]

DISPLAY

007

EXIT TO TUB1/TA81
PATHFINDER, FAULT

CODE SECTION.
PERFORM FAULT

CODE PROCEDURE.

[

:
RUN TEST 01 1

OR HSC DIAGNOSTICS

DISPLAY - 00°?

SERVICE

COMPLETED

MA LA

SHiF

D448 B~

129

C MALFUNCTION MATRIX
Corrective Action

A
SR
'fio Q\Q%

N &‘23’ &QQ Q.\\c Qoo

Malfunction
When you press the power switch on (1), the

81514

|76

1|9

LOGIC ON indicator does not light.
TUS81 displays 00 on power-up.

TU81 powers down while in use.

Control panel switch does not operate.

TUS81 operates with top cover open.

FILE PRO indicator does not light when a

write-protected tape is loaded.

Take-up reel does not turn freely.

Supply reel does not turn freely.
Supply reel hub cannot be latched.
Excessive pneumatic noise.

130

1
1

—)

) UNIBUS ADAPTERS

(M8739)

Installing Additional UNIBUS Adapters (M8739)

The M8739 module is factory configured to 772150(8).
This address is for a primary MSCP tape/disk used on a
system.

For the first TU81 in a system, the M8739 module
must be set to address 774500(8), as shown in Figure 2-5.
To install additional M8739 modules, an address must be
selected for each module from the floating device address
range. This range includes addresses from 760010(8)
through 763776(8).
The module’s vector is set by software.

To configure a module for installation in a VAX system,
use the SYSGEN procedure found in Table 2-3 to determine the module’s address.
To configure a module for installation in a PDP-11 sys-

tem, use the FLOAT utility under XXDP. In an XXDP
directory, FLOAT is listed as ZFLACO0.BIN. At the XXDP

prompt, use the run command to run the utility. You'll be
told to input the option that you want: use FA if the devices
that you need addresses for have vectors that are set by
software (like the TUS81); use VA if you need vector
assignments in addition to addresses. Whichever option

you choose, the utility prompts you to input the number of
each type of device that you have in the system. The utility
then displays the address that each device should be

assigned.
If you cannot use SYSGEN (on a VAX system) or the
FLOAT utility

(on

PDP-11

system),

follow these

guidelines to determine the module’s address.

Choosing an address from the floating address range is a
process of finding a value called “nnn,” and adding that
value to a base address of 760000. Since the smallest nnn
value that can be used is 010, the range of addresses
begins at 760010.

To determine an nnn value, and then produce an
address from the floating address range (760010 through
763776), list all modules to be installed in the system that
require floating addresses.

131

132

APPENDICES

Look for these modules on the following ranking table.
The size column lists a number of words (in decimal), the

modulus column lists a number of bytes (in octal). In
addition, the modulus column must be used as a number

that the nnn value of the address is divisible by, that is,

nnn can be divided by the modulus value and the result is

a whole number. The examples following the table show
how the modulus is used.

DJ11

DHI11

Modulus

DQI1

DUI1, DUVII

DUPI1

LKITA

DMC11/DMR11
DZ11/DZV11, DZS11,

S~
5 b

o0~
O

wn bW

Device

Octal
Rank

10
10

DZ32

KMC11
S~

DWRT70

RLIT,RLVII

LPA11-K

LPPI11

VMV21

VMV31

KWI11-C

Reserved

RX11/RX211,

DR11-W

DR11-B

DMP11

SN0
I N S S

RXVI11/RXV21

DPVI1I

ISB11
DMVI11
DEUNA

10
20

APPENDICES

UDAS0, RQDX1,

4
40

133

RUC25, RUX50
27

DMF32

KMSI11

VS100

TUSI

KMV11

DHVI11, DHU11

DMZ32, CPI (asynch)

CPI32 (synch)

For example, the first floating CSR address is 760010

and the first device in the table is the DJ11. If we have a
DJ11, its CSR address would be at 760010. If we don’t

have a DJ11, address 760010 must be left blank, that is,
cannot be assigned to any device.

If we do have a DJ11, we assign it the address of
760010. The size column in the table indicates that the

module’s size is 4 words (8 bytes). This requires addresses
760010 through 760016. The next available address is

then 760020.
If we had a second DJ11, it would be assigned address
760020. There are two reasons for this assignment.

Since the first DJ11 is assigned address 760010 and

its size requires 4 words, it uses addresses 760010
through 760016 (4 word locations). That makes the
next available address 760020.
2.

The DJ11, according to the table, has a modulus of

10. The states that the nnn value of the address to be

used must be divisible by the modulus. For address
760020, the nnn value is 020 — this number is divisi-

ble by 10 and results in a whole number (2).
If we didn’t have a second DJ11, address 760020 could
not be assigned to any device. This address must be left
vacant to let the system know that there is not a second

DJ11 occupying a location in the floating address range.

Since 760020 must be left vacant, 760022 is the next
available address for use in the floating address range. The
vacancy of 760020 indicates that there are no more
DJ11s.

134

APPENDICES

Note that the next available address (760022) has nothing to do with how many addresses a second DJ11 would

require IF one was present. Only one address needs to be
left vacant to indicate that there is no second DJ11
installed — as already stated, the vacant address must be
760020.

NOTE
This is the key to assigning addresses from the

floating range. Just as a response from an
address identifies to the system what kind of

device is present, a vacant address identifies
what kind of device is not present. “Gaps”
(unused addresses) must be left to tell the system which devices are NOT present.

The next device on the list is the DH11, which is listed
with a modulus of 20. The next available address (that we
left off with earlier in our example) was 760022. The nnn
field of 022 cannot be used for the DH11, since 22 cannot
be divided by 20. In fact, the next nnn field that can be
used is 040. So, to install a DH11 into this system, its
address would be set to 760040. Since the size listed for
the DH11 is 8 (words), the DH11 would use addresses
760040 through 760056, making the next available
address 760060.

If we do not install a DH11 into this system, address
760040 has to remain vacant. This makes 760042 the next
available address.

Let’s take another example - one that applies to the
TUSI.

Suppose we have three options that require floating
addresses: one DZ11 and two TUS81 subsystems.
Determine the list of addresses that would be vacant,
and the addresses that would be used by these modules.

See if your answer agrees with the following list (vacant
addresses are listed with the corresponding ‘““missing module” that they represent).

APPENDICES

135

760010 Vacant (DJ11)
760020 Vacant (DHI11)*
760030 Vacant (DQ11)

760040 Vacant (DU11, DUVII)
760050 Vacant (DUP11)
760060 Vacant (LK11A)
760070 Vacant (DMC11/DMR11)
760100 Setting for the DZ11 module
760110 Vacant (no additional DZ11)
760120 Vacant (KMC11)

760130 Vacant (LPP11)
760140 Vacant (VMV21)
760160 Vacant (VMV31)*
760170 Vacant (DWR70)
760200 Vacant (RL11)

760220 Vacant (LPA11-K)*
760230 Vacant (KW 11-C)
760240 Vacant (Reserved)
760250 Vacant (RX11)
760260 Vacant (DR11-W)
760270 Vacant (DR11-B)

760300 Vacant (DMP11)
760310 Vacant (DPV11)

760320 Vacant (ISB11)
760340 Vacant (DMV11)*
760350 Vacant (DEUNA)
760354 Vacant (UDASOQ)*
760400 Vacant (DMF32)*
760420 Vacant (KMSI11)*
760440 Vacant (VS100)*
760444 Setting for a TU81 subsystemTM
760450 Setting for another TU81 subsystemTM

* Indicates addresses for devices where the modulus is
NOT 10. Don’t forget that the nnn value of the address
that you select must be divisible by that device’s modulus to produce a whole number.
Since these addresses include all the devices to be added
for our example, all remaining addresses in the floating
range are vacant.