Texas Instruments WD800 User manual

•.
INSTALLATION AND OPERATION~
WDBOO/WDBOOA
Mass Storage System
Part No. 2306140-9701 *B
February 1985
TExAs INSTRUMENTS

© 1982, 1985 Texas Instruments Incorporated. All Rights Reserved.
Printed in U.S.A.
No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or
by any means, electronic, mechanical, photocopying, recording, or otherwise, without the priol' written
pmmission of Texas Instruments Incorporated.
MANUAL REVISION HISTORY
WD800/WD800A Mass Storage System Installation and Operation
(2306140-9701)
Original Issue ................................... June 1982
Revision ........................................ February 1985
The~ total number of pages in this publication is 178.
The computers, as well as the programs that Tl has created to use with them, are tools that
can help people better manage the i11formation used in their business; but tools-including
Tl computers-cannot replace sound judgment nor make the manager's business
decisions.
Consequently, Tl cannot warrant that its systems are suitable for any specific customer
application. Ttle manager must rely on judgment of what is best for his or herbusiness.

WARNING: This equipment generates, uses, and can radiate radio frequency
energy and if not installed and used in accordance with the instructions manual,
may cause interference to radio communications. It has been tested and found to
comply with the limits for a Class A computing device pursuant to Subpart J of
Part 15 of FCC Rules, which are designed to provide reasonable protection
against such interference when operated in a commercial environment. Operation
of this equipment in a residential area is likely to cause interference in which case
the user at his own expense will be required to take whatever measures may be
required to correct the interference.
This Document: 2540205-0001

Preface
This manual provides detailed instructions for installing and operating a WD800 or WD800A mass
storage system. It also contains programming information for those users who write their own
input/output routines. The information in this manual is divided into five sections and three
appendixes as follows:
Section
NOTE
The WD800 and WD800A operate in a similar manner. They primarily
differ in the storage capacities of the Winchester disk drives. Unless
noted otherwise, when this manual refers to the WD800, the
information applies to both the WD800 and the WD800A disk units.
1 WD800 System Kit Description -Briefly describes the features and major components
of the WD800 system.
2 TILINE Peripheral Bus Interface (TPBI) -Describes the operation of the TPBI and
explains the procedures for unpacking, installing, and programming the TPBI board.
3 WD800 Chassis Installation and Programming -Provides site requirements and step-
by-step instructions for unpacking, installing, and programming the chassis.
4 WDBOO System Kit Installation -Explains the kit-level installation of the WD800
system, system self-tests and diagnostics, and procedures for system checkout.
5 Operation -Describes the operator's use of the system.
Appendix
A Fault Analysis -Provides information for use in analyzing system fault conditions.
B TPBI System Command Trace Feature -Provides operating instructions for using the
TPBI command trace in troubleshooting system problems.
C Sample 990 Device Service Routines -Provides instructions and sample device service!
routines (DSRs) for users who write theirown input/output routines.
2306140-9701 iii

Preface
The following documents contain additional information related to the WD800 mass storage
system:
iv
Title
Business Systems 6001800 Field Engineering
Reference Handbook
WD800/WD800A Mass Storage System
Field Maintenance Manual
Model 990112 Computer Hardwarie User's Manual
Model 990112 LR Computer General Description
Model 990110 Computer System
Hardware Reference Manual
Model 990/10A Computer General Description
Model 990A 13 Chassis General Description
Model 990 Computer 990110 and 990112 Assembly
Language Reference Manual
Model 990 Computer Family Maintenance Drawings,
Volume 4 - Tl LINE Expansion and Peripherals
Unit Diagnostic Handbook, Volume 1-General 990
Unit Diagnostic Information
Unit Diagnostic Handbook, Volume 3 - Diagnostics
for 990 Mass Storage Devices
Model 990 Computer TILINE Peripheral Bus Interface
Depot Maintenance Manual
DX10 Operating System Manual,
Volume II -Operation Manual
DX10 Operating System Manual, Volume V- Systems
Programming Guide
Universal ROM Loader User's Guide
DNOS System Command Interpreter Reference Manual
DNOS Operations Guide
Part Number
2311344-9701
2306142-9701
2264446-9701
2268239-9701
945417-9701
2302633-9701
230877 4-9701
2270509-9701
945421-9704
945400-9701
945400-9703
2306143-9701
946250-9702
946250-9705
2270534-9701
2270503-9701
2270502-9701
2306140-9701

2306140-9701
Tltle
DNOS System Generation Reference Manual
Business Systems 6001800 Installation Manual
Part Number
2270511-9701
2311341-9701
Preface
v/vi

Paragraph
1.1
1.2
1.2.1
1.2.2
1.2.3
1.2.3.1
1.2.3.2
1.2.3.3
1.2.3.4
1.2.3.5
1.3
1.4
1.4.1
1.4.2
1.4.3
1.4.4
1.4.5
1.4.5.1
1.4.5.2
1.4.5.3
1.4.5.4
1.5
2.1
2.1.1
2.1.2
2.1.3
2.1.4
2.2
2.2.1
2.2.2
2.2.3
2.2.4
2.2.4.1
2.2.4.2
2.2.5
2306140-9701
Contents
Title
Page
1 - WD800/WD800A System Kit Description
General ................................................................ 1-1
Kit Components ........................................................ 1-3
TPBI Board ........................................................... 1-4
Peripheral Bus Cable ................................................... 1-4
WD800 Chassis ....................................................... 1-4
Winchester Disk Drive ................................................ 1-4
Magnetic Tape Cartridge Transport ..................................... 1-5
Front Panel Controls and Indicators .................................... 1-5
Card Cage .......................................................... 1-5
Power Supply ....................................................... 1-5
O~)tions ..... : .......................................................... 1-6
F~inctional Description ................................................... 1-7
!General .............................................................. 1-7
iTILINE ............................................................... 1-8
iTPBI ................................................................ 1-8
Peripheral Bus Interface (PBI) ........................................... 1-8
!Formatter Function .................................................... 1-9
System Initialization ................................................. 1-9
Winchester Disk Subsystem Operations ................................. 1-9
Tape Transport Operations ........................................... 1-11
Status Monitoring and Reporting ...................................... 1-12
F~mctional Specifications ............................................... 1-12
2 - TILINE Peripheral Bus Interface
G(3neral ................................................................ 2-1
:System Operational Description ......................................... 2-1
TILINE .............................................................. 2-3
,TPBI Operations ...................................................... 2-3
! Peripheral Bus Interface ................................................ 2-4
TEJBI Programming ...................................................... 2-4
;TILINE Communication ......................................... - ....... 2-5
TILINE Peripheral Control Space Addressing .............................. 2-5
TPBI Command and Status Structure ..................................... 2-7
:Command Completion ................................................. 2-7
Command Completion Without Interrupts ............................... 2-7
Command Completion With Interrupts .................................. 2-7
1 TPBI Disk Control and Status Word Formats
............................... 2-8
vii

Contents
Paragraph
2.2.5.1
2.2.5.2
2.2.5.3
2.2.5.4
2.2.5.5
2.2.5.6
2.2.5.7
2.2.5.8
2.2.6'
2.2.6.1
2.2.6.2
2.2.6.3
2.2.6.4
2.2.6.5
2.2.6.6
2.2.6.7
2.3
2.3.1
2.3.2
2.3.3
2.3.4
2.3.5
2.3.5.1
2.3.5.2
2.3.5.3
2.3.5.4
2.3.6
2.3.7
2.3.8
2.3.8.1
2.3.8.2
2.3.8.3
3.1
3.2
3.2.1
3.2.2
3.2.2.1
3.2.2.2
3.2.3
3.2.4
3.2.5
3.2.5.1
3.2.5.2
3.2.5.3
3.3
viii
Title Page
WO - Attention ...................................................... 2-8
W1 -Commands ................................................... 2-10
W2 -Self-Test Errors ............................................... 2-111
W3 -Maintenance Commands ...................................... 2-11
W4 -Transfer Byte Count ............................................ 2-12
W5 -MemoryAddress (LSB) ........................................ 2-12
W6 -Unit Select and Memory Address (MSB) ........................... 2-12
W7 -Command Completion Status .................................. 2-13
TPBI Tape Control and Status Word Formats ............................. 2-14
WO -Rewind Status ................................................ 2-14
W2 -Self-Test Status and Internal Address ............................ 2-16
W3 -Maintenance Commands ...................................... 2-16
W4 -Transfer Byte Count ........................................... 2-16
W5 -MemoryAddress (LSB) ........................................ 2-16
W6 -Unit Select and Command Codes ............................... 2-H>
W7 -Command Completion Status .................................. 2-18
TPBI Installation ....................................................... 2-19
Preparation for Use ................................................... 2-19
Unpacking .......................................................... 2-19
Inspection ........................................................ ; ... 2-20
TPBI Board Switch Setting ............................................. 2-20
990 Computer Chassis Preparation for the TPBI ........................... 2-21
Selecting a Chassis Slot for the Controller ............................. 2-2·1
TILINE Philosophy ................................................. 2-22
Preparing a 990 Chassis Slot Location for the TPBI ...................... 2-22
Interrupt Connections .............................................. 2-30
Installation of TPBI Board in El-Slot or 13-Slot Chassis ...................... 2-36
Installation of TPBI Board in 17-Slot Chassis .............................. 2-36
TPBI Verification ..................................................... 2-37
FAULT Indicator ................................................... 2-37
TILINE Indicator ................................................... 2-37
Busy LEDs A and B .................................................. 2-37
3 - WDSOO Chassis Installation and Programming
General ................................................................. 3- ·1
Installation .............................................................. 3-·1
Site Preparation ....................................................... 3-·1
Unpacking ............................................................ 3-4
Shipping Configuration .............................................. 3-4
Unpacking Procedure ................................................. 3-4
Chassis Preparation ................................................... 3-6
Chassis Installation in an EIA Cabinet .................................... 3-9
Chassis Stand-Alone Power-Up and Unit Select ........................... 3-1!5
Chassis Power-Up .................................................. 3-1fi
Unit Select ........................................................ 3-17
Tape System Verification ............................................ 3-18
Programming .......................................................... 3-18
2306140-9701

Paragraph
3.3.1
3.3.2
3.3.2.1
3.3.2.2
3.3.3
3.3.3.1
3.3.3.2
3.3.3.3
3.3.3.4
3.3.3.5
3.3.3.6
3.3.4
3.3.4.1
3.3.4.2
3.3.4.3
3.3.5
3.3.5.1
3.3.5.2
3.3.6
3.3.6.1
3.3.6.2
3.3.6.3
3.3.6.4
3.3.6.5
3.3.6.6
3.3.6.7
3.3.7
3.3.7.1
3.3.7.2
4.1
4.2
4.2.1
4.2.2
4.2.2.1
4.2.2.2
4.2.3
4.2.4
4.2.5
4.2.5.1
4.2.5.2
4.2.5.3
4.2.6
2306140-9701
Contents
Title Page
General ............................................................. 3-19
Disk Programming ................................................... 3-19
Disk Command Summary ............................................ 3-19
Disk Control and Status Block -Summary ............................. 3-20
Disk Control and Status Word Formats .................................. 3-20
WO -Disk Status .................................................. 3-22
W1 -Command and Head Address ................................... 3-22
W2 -Sectors per Record and SectorAddress .......................... 3-24
W3 -Cylinder Address or Maintenance Commands ..................... 3-24
W4 -Transfer Byte Count ........................................... 3-25
W7 -Command Completion Status .................................. 3-25
Detailed Disk Command Descriptions ................................... 3-26
Normal Commands ................................................. 3-26
Extended Mode Commands .......................................... 3-30
Maintenance Commands (W1 = >87XX) ............................... 3-30
Tape Programming ................................................... 3-31
Tape Command Summary ........................................... 3-31
Tape Control and Status Block -Summary ............................ 3-32
Tape Control and Status Word Formats .................................. 3-32
WO -Tape Status .................................................. 3-32
W1 -Read Overflow ............................................... 3-34
W2 -Self-Test Status and Internal Address ............................ 3-34
W3 -Read Offset or Maintenance Command .......................... 3-35
W4 -Byte/Record Count ............................................ 3-35
W6 -Command ................................................... 3-35
W7 -Command Completion Status .................................. 3-36
Detailed Tape Command Descriptions ................................... 3-37
Normal Commands ................................................. 3-37
Special Commands ................................................. 3-42
4 - WD800 System Kit Installation
General ................................................................ 4-1
Installation ............................................................. 4-1
General Overview ..................................................... 4-1
Configuring the WD800 Terminator Packs and Grounds ..................... 4-2
Configuring the WD800 Terminator Packs ............................... 4-2
Configuring the WD800 Grounds ....................................... 4-4
Installing the PBI Cable ................................................ 4-5
Installing the Power Cord ............................................... 4-8
Power-Up and System Test ............................................. 4-8
Power-Up .......................................................... 4-9
System Start-Up ..................................................... 4-9
System Diagnostics ................................................ 4-10
Power-Down ......................................................... 4-14
ix

Paragraph
5.1
5.2
5.2.1
5.2.1.1
5.2.1.2
5.2.1.3
5.2.2
5.2.2.1
5.2.2.2
5.2.2.3
5.2.2.4
5.2.2.5
5.3
5.3.1
5.3.2
5.3.2.1
5.3.2.2
5.3.2.3
5.3.2.4
5.3.2.5
5.3.2.6
5.3.2.7
5.4
5.4.1
5.4.2
Appendix
A
B
c
x
Contents
Title Page
5 -· Operation
General ................................................................ 5-·t
Controls and Indicators .................................................. 5-·t
Controls ............................................................. 5-·1
Ac Power Switch .................................................... 5-·1
TEST STATUS/TAPE UNLOAD Switch .................................. 5-·1
DISK WRITE-PROTECT Switch ........................................ 5-4
Indicators ............................................................ 5-4
Tape Status Indicator (TAPE READY) ................................... 5-4
System Status Indicator (SYSTEM READY) .............................. 5-5
Disk Status Indicator (DISK READY) .................................... 5-5
Test Status Indicator (TEST MODE) .................................... 5-5
Indicator Secondary Functions ........................................ 5-6
Operating Procedures ................................................... 5-6
DiskSubsystem Operation ............................................. 5-6
Tape Subsystem Operation ............................................. 5-6
Media Requirements ................................................. 5-7
Cartridge Handling .................................................. 5-7
Tape Write-Protection ................................................ 5-7
Cartridge Insertion .................................................. 5-7
Cartridge Unloading and Removal ...................................... 5-8
Environmental Requirements for the Tape Cartridge ..................... 5-10
Power-Down Procedure .............................................. 5-10
Operator Preventive Maintenance .......................................... 5-10
Tape Transport Head, Capstan, and SensorCleaning ....................... 5-10
Air Filter Cleaning ..................................................... 5-12
Appendixes
Title Page
Fault Analysis .......................................................... A .. 1
TPBI Command Trace Feature ............................................ B··1
Sample 990 Device Service Routines ....................................... C-1
Index
2306140-9701

Contents
Figure
1-1
1-2
1-3
1-4
2-1
2-2
2-3
2-4
2-5
2-6
2-7
2-8
2-9
2-10
2-11
2-12
2-13
2-14
2-15
3-1
3-2
3-3
3-4
3-5
3-6
3-7
3-8
3-9
3-10
3-11
3-12
3-13
4-1
4-2
4-3
4-4
5-1
5-2
5-3
5-4
5-5
5-6
5-7
2306140-9701
Illustrations
Title Page
WD800 System Kit ....................................................... 1-2
WD800 Chassis ......................................................... 1-4
WD800 Maximum Configuration ........................................... 1-6
WD800 Functional Diagram ............................................... 1-7
TPBI Block Diagram ..................................................... 2-2
TPBI Board ............................................................. 2-2
Mass Storage System Using TPBI as 990 Interface ............................ 2-3
Relationship Between TILINE Address and CPU Byte Address .................. 2-6
Disk Control and Status Word Formats ..................................... 2-9
Tape Control and Status Word Formats .................................... 2-15
TLAG Jumper Locations for 6-Slot Chassis (Current Production) ............... 2-23
TLAG Jumper Locations for 13-Slot Chassis (Current Production) .............. 2-24
TLAG Jumpers on Early Production 6-Slot and 13-Slot Chassis ................ 2-26
Interrupt Plug and TLAG JumperSwitches in the 17-Slot Chassis .............. 2-28
17-Slot Chassis TLAG Jumper Switch Settings .............................. 2-29
Location of Interrupt Jumpers, 6-Slot and 13-Slot Chassis .................... 2-33
6-Slot Chassis Interrupt Jumper Plugs ..................................... 2-33
13-Slot Chassis Interrupt Jumper Plugs .................................... 2-34
17-Slot Interrupt Jumper Connector ....................................... 2-35
Minimum Requirement for Power Service for WD800 Equipment ................ 3-2
WD800 Chassis -Individual Container ..................................... 3-5
Shipping Bolt Locations (WD800 Only) ...................................... 3-7
View of Actuator Lock Mechanism in Unlocked Position (WD800 Only) ........... 3-8
EIA Mounting Rails ...................................................... 3-9
Standard 0.82 Meter(32-lnch) Cabinet ..................................... 3-10
Perspective View of Slide Mounts ......................................... 3-11
Mounting InnerSlides to Chassis ......................................... 3-13
Chassis AC Power Cord Cable Clamp ...................................... 3-15
Disk Control and Status Word Formats for Direct Disk 1/0 Operations ........... 3-21
Read ID Format ........................................................ 3-29
Tape Control and Status Word Formats .................................... 3-33
Read Offset and Overflow for Partial Record Read ........................... 3-39
Location of the Interface PCB ............................................. 4-3
Location of Terminator Packs ............................................. 4-4
WD800 Chassis Ground Selection Jumper Plug .............................. 4-6
WD800 System Cabling .................................................. 4-7
WD800 System Front Panel ............................................... 5-2
WD800 System Rear Panel ................................................ 5-3
Tape Write-Protection Plug ............................................... 5-8
Cartridge Insertion ...................................................... 5-9
Tape Heads, Cleaner, Capstan, and Sensors ................................ 5-11
Air Filter Removal ...................................................... 5-13
Alternate Front Panel Filter Removal ...................................... 5-14
xi

Contents
Tables
Table Title Page
1-1 System Component Part Numbms ......................................... 1-:3
1-2 WDBOO Mass Storage System Specifications ............................... 1-13
1-3 Disk Subsystem Specifications ........................................... 1-14
1-4 Tape Subsystem Specifications .......................................... 1-16
2-1 Command Codes ....................................................... 2-11
2-2 TPBI Maintenance Commands ........................................... 2-16
2-3 Tape Command Codes .................................................. 2-1'7
2-4 TILINE Address Switch Configurations .................................... 2-21
3-1 WD800 Subsystem Installation Requirements ............................... 3-3
3-2 Test Status Indicators During Unit Selection ................................ 3-18
3-3 Disk Commands ....................................................... 3-23
3-4 Tape Commands ....................................................... 3-36
xii 2306140-9701

1
WD800/WD800A Syst~m Kit Description
1.1 GENERAL
The Model 990 Computer WD800 and WD800A Mass Storage System Kits (Figure 1-1) provide
random-access mass data storage systems for any Texas Instruments Model 990 Computer with a
TILINE™, the Tl asynchronous, 16-bit parallel data bus that transfers data between high-speed
system elements. The WD800 systems use Winchester disk technology for the primary storage
device, and provide removable backup storage with a magnetic tape cartridge. Up to four
Winchester disk drives with four tape cartridge transports can be connected in a daisy-chained
configuration to a single controller installed in the host system. The host system can be any 990
computersystem with an interface meeting the requirements of the TILINE.
NOTE
The WD800 and WD800A operate in a similar manner. Unless noted
otherwise, when this manual refers to the WD800, the information
applies to both the WD800 and the WD800A disk units.
The WD800 mass storage system kit includes the following features:
• Single circuit board 990 TILINE peripheral bus interface (TPBI) controller
• Plug compatible with WD500/WD500A mass storage systems
• Compatibility with 990 computersystems
• Winchesterdisk with error correcting code (ECC) forerrorchecking and correcting
capability
• Microprocessor-based controller logic
• Cartridge tape removable medium
• Integral power supply
• Rackmount ortabletop configuration
• Support for all standard Texas Instruments international voltage/frequency
combinations
TILIN Eis a trademark of Texas Instruments Incorporated.
2306140-9701 1·1

WDBOOIWDBOOA System Kit Description
DISK UNIT
TPBI BOARD
(FOR BUSINESS SYSTEM 600/800 APPLICATIONS)
TAPE CARTRIDGE
2285508
Figure 1·'11. WD800 System Kit
PERIPHERAL BUS
INTERFACE
CABLE
POWER
CORD
INSTALLATION AUD OPERA TIOk ..
Model
W DBOO/W DBOOA
Mass Storage System
TEXAS INSTRUMENTS
DISK UNIT
INSTALLATION AND
OPERATION MANUAL
1-2 2306140·9701

WDBOOIWDBOOA System Kit Description
1.2 KIT COMPONENTS
The WDBOO system kit consists of the following majorassemblies:
• TPBI board
• Peripheral bus cable
• WDBOO system chassis that includes the following:
Winchester disk drive assembly
Magnetic tape cartridge transport assembly
Front panel controls and indicators
Card cage with motherboard and printed circuit boards (PCBs) for the formatter
function and the disk and tape cartridge electronics
Power supply
Major system component part numbers are listed in Table 1-1.
Table 1 ·1. System Component Part Numbers
Component
WD800 Storage System Chassis
WD800A Storage System Chassis
Peripheral Bus Cable Assembly
TPBI Assembly
Tape Cartridge Media:
137 m (450 ft)
Notes:
Part Number
2215801-XXXX1 (Chassis mount -Not shown)
or
2213097-XXXX1 (Chassis mount -Figure 1-2)
or
2213074-XXXX1 (Table top -Figure 1-1)
2245216-0037 through 00721·2 (Chassis mount -not shown)
or
2245216-0001 through 00361·2 (Table top -not shown)
2308633-0003
2270820-0001
2270391-0001
1 The dash number indicates the exact voltage, frequency, and
disk capacity specifications of the system.
2 Similar in appearance
to the WD800.
2306140-9701
1·3

WDBOOIWDBOOA System Kit Description
1.2.1 TPBI Board
The TPBI board occupies one full slot in th·e 990 chassis and furnishes communication between
the 990 system and the formatter in the WDBOO system. The TPBI uses the TILINE for host system
communication and the peripheral bus interface (PBI) for formatter communication.
1.2.2 Peripheral Bus Cable
The peripheral bus cable connects the TPBI board to the WD800 chassis and interconnects daisy-
chained chassis. The system uses a 40-pin cable connector assembly with a metal backshell to
minimize electromagnetic interference (EMii). The maximum cable length is 15 meters (49.2 feet).
Cable terminator resistor packs are inside the WD800 chassis.
1.2.3 WD800 Chassis
The WD800 chassis (Figure 1-2) contains the Winchester disk drive, the magnetic tape cartridge
transport, the front panel controls and indicators, the card cage, and the powersupply assembly.
1.2.3.1 Winchester Disk Drive. The disk drive subassembly consists of a die-cast deck with a
sealed area for heads, platters, and servo-positioning motor. The spindle motor, spindle motor
brake, positioner locking mechanism, and electronics are mounted beneath the sealed housing.
2282700
Figure 1 ·:2. WD800 Chassis
1·4
2306140-9701

WDBOO/WDBOOA System Kit Description
1.2.3.2 Magnetic Tape Cartridge Transport. The magnetic tape cartridge transport subassembly
is optional in all chassis except one where it is required to provide backup. The tape transport
subassembly includes the following items:
• Tape transport drive assembly that consists of the following:
Transport (deck, motor, heads, sensors, and cables)
Transport mounting brackets
Tape subsystem analog PCB assembly
• Tape subsystem analog PCB powercable
• Transport-to-encode/decode PCB cable
• Tape encode/decode PCB assembly
• Tape control PCB assembly
1.2.3.3 Front Panel Controls and Indicators. The WD800 system chassis has three controls: the
ac power switch, the TEST STATUS/TAPE UNLOAD switch, and the DISK WRITE-PROTECT switch.
The ac power switch is located on the chassis rear panel. Turning on the ac power switch initial-
izes the system. The other two switches are located on the front panel. The TEST STATUS/TAPE
UN LOAD switch, a three-position, spring-loaded, momentary-action switch, selects either test
status or tape unload mode. The DISK WRITE-PROTECT switch selects the write-protect mode for
the disk when it is on.
The WD800 system chassis has four indicator lights on the front panel: a tape status indicator, a
storage system indicator, a disk status indicator, and a test mode indicator. These lights perform
three functions. Primarily, they display the operational status of the storage system. The lights can
also display detected subassembly faults by toggling the TEST STATUS/TAPE UNLOAD switch up.
Under certain conditions during stand-alone power-up initialization, the lights also display the unit
select address.
1.2.3.4 Card Cage. The card cage contains the peripheral interface board, the processor board,
the Winchester disk interface board (WD800A only), the read/write board (WD800 only), the high-
speed digital board, and the servo board (WD800 only). If the chassis contains the optional tape
cartridge transport subsystem, the card cage also contains the tape encode/decode board and the
tape control board. A group of processes executed by these boards constitutes the formatter func-
tion of the WD800 system.
1.2.3.5 Power Supply. The WD800 chassis power supply consists of an electro-magnetic induc-
tion (EMI) filter and two power supply boards. For the power supply requirements of the WD800
chassis, see Table 3-1.
2306140-9701 1·5

WDBOO/WDBOOA System Kit Description
1.3 OPTIONS
The WD800 system is available with either a two-platter or a four-platter Winchester disk drive. The
two-platter disk drive provides a disk storage capacity of 18.5 megabytes, and the four-platter disk
drive provides a disk storage capacity of 43.~~ megabytes.
The WD800A system is available with a three-platter, a five-platter, or an eight-platter Winchester
disk drive. The three-platter disk drive provides a disk storage capacity of 38.4 megabytes, the five-
platter disk drive provides a disk storage capacity of 69.2 megabytes, and the eight-platter disk
drive provides a disk storage capacity of 114.5 megabytes.
The WD800 system kit design permits a wide variety of possible chassis configurations (Figure
1-3). At the minimum, the system consists of only one chassis with a Winchester disk drive and a
magnetic tape cartridge transport installed in the chassis for backup. The maximum configuration
that a single TPBI board can support consists of four daisy-chained chassis, each with a disk drive
and a magnetic tape cartridge transport installed for backup.
The WD800 system also works with other peripherals. For example, you can mix WD800 and
WD500/WD500A system chassis in the same system. This combination might occur when you
expand the storage capacity of a smaller system by adding aWD800 system kit.
1·6
I
I
I
I
TPBI
(2270820-0001)
IHOST
~OMPUTE~_£HASS~ _ J
NOTE:
DISK DRIVE 2
(REAR VIEW)
SECONDARY
DISK DRIVE I
(REAR VIEW)
DISK DRIVE 3
(REAR VIEW)
SECONDARY
DISK DRIVE 4
(REAR VIEW)
PRIMARY
I. TOTAL CABL.E LENGTH MUST NOT EXCEED 1 5M. AVAILABLE CABLE LENGTHS ARE
2. f~RU'(~Af5~
8
ttJi(s?'1.i~ iN~~A):~~D
2
i~~
8
f~tf·~~~~Ff~~ JJ'~JP6j:;! f~~
8
~N-rii~~t· 1N THE
CHAIN (PRIMARY DRIVE).
2283753
Figure 1·3. WD800 Maximum Configuration
2306140-9701