HP 98625A User manual

HP Computer Systems
HP 98625A
Disc Interface Installation
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HP Computer Systems
HP 98625A
Disc Interface Installation
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Warranty Statement
Hewlett-Packard products are warranted against defects
in
materials and workmanship. For Hewlett-Packard Desktop
Computer Division products sold
in the U.S.A. and Canada,
this warranty applies for ninety (90) days from the date of
delivery.* Hewlett-Packard will, at its option, repair or replace
equipment which proves to be defective during the warranty
period. This warranty includes labor, parts, and surface
travel costs, if any. Equipment returned to Hewlett-Packard
for repair must be shipped freight prepaid. Repairs
necessitated by misuse of the equipment, or by hardware,
software, or interfacing not provided by Hewlett-Packard are
not covered by this warranty.
HP warrants that its software and firmware deSignated by HP
for use with a CPU will execute its programming instructions
when properly installed
on that CPU. HP does not warrant
that the operation of the
CPU, software, or firmware will be
uninterrupted or error free.
NO OTHER WARRANTY IS EXPRESSED OR IMPLIED,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES
OF MERCHANTIBILITY AND FITNESS FOR
A PARTICULAR PURPOSE. HEWLETI-PACKARD SHALL
NOT
BE LIABLE FOR CONSEQUENTIAL DAMAGES.
*For other countries, contact your local Sales and Service
Office to determine warranty terms.

HP 98625A
Disc Interface Installation
Part No. 98625-90000
,~: Copyright Hewlett-Packard Company, 1982
This document refers to proprietary computer software which is protected by
copyright. All rights are reserved. Copying or other reproduction of this program
except for archival purposes is prohibited without the prior written consent of
Hewlett-Packard Company.
Hewlett-Packard
Roseville Networks Division
8000 Foothills Boulevard
Roseville, California 95678

ii
Printing History
New editions of this manual will incorporate all material updated since the previous edition.
Update packages may be issued between editions and contain replacement and additional
pages to
be merged into the manual by the user. Each updated page will be indicated by a
revision date at the bottom of the page. A vertical bar
in the margin indicates the changes on
each page. Note that pages which are rearranged due to changes on a previous page are not
considered revised.
The manual printing date
and part number indicate its current edition. The printing date
changes when a new edition
is printed. (Minor corrections and updates which are incorporated
at reprint
do not cause the date to change.) The manual part number changes when extensive
technical changes are incorporated.
June 1982 ... First Edition
September
1983 ... Update 1
September
1983 ... Reprint (incorporating Update 1)

Table of Contents
Chapter 1: Interface Installation and Configuration
Introdluction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1
Parts :Supplied . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2
HandHng the Interface
Card. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2
Installing Interface Cards in the I/O Backplane
.................................... 3
Configuring
the Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 4
Conn1ecting the Interface to Disc Drivers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 6
Interface Cables. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.. 6
Physical Arrangement of Equipment
...... ~ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 6
Li:mitations
.............................................................. 7
Chapter 2: Service Information
Theory of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 9
Parts List
and Schematic Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 9
Figures
Tables
HP 98625A Disc Interface Configuration Switches. . . . . . . . . . . . . . . . . . . . . . . . . .. 4
Recommended Arrangement of Computer and Disc Drives. . . . . . . . . . . . . . . . . . .. 7
Disc Interface Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.. 9
Parts
Supplied. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2
Default Configuration Settings
............................................ 4
Interface Select
Code Switch Settings ...................................... 5
Binary/Decimal Table of Hardware Interrupt Levels
.......................... 5
Available HP-IB Interface Cables
......................................... 6
Disc Interface Cable Length Limits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.. 7
Replaceable Parts List
................................................. 10
iii

iv

Chapter 1
Interface Installation and Configuration
Introduction
The HP 98625A Disc Interface is used in conjunction with an HP 98620 DMA card to connect
your
HP 9826 or HP 9836 computer to one or more mass storage disc drives. The interface is
compatible with all Hewlett-Packard CS/80 disc drives including the following HP 7900 Series!
units:
• HP 7908
• HP 7911
• HP 7912
To minirnize potential difficulties, don't forget that:
• The interface contains a high-speed HP-IB controller, and is designed specifically for disc
appllications. Because of its high data rates and fast signal transition times, the interface is
not suitable for use with other HP-IB peripherals.
• High-speed data transfers demand direct memory access capability; therefore, the inter-
face
cannot be used without a DMA card installed in the computer.
• The HP 10833 HP-IB chaining cables used with this interface are designed for high-
frequency applications. To ensure reliable operation,
do not use any other cable type.
Note
The HP 98625 Disc Interface requires an HP 98620 DMA card for
operation. It
cannot be used without DMA capability installed in the
computer. Use only 256K-byte memory boards in combination with
the disc interface and DMA card.
This manual explains the installation procedure for the disc interface. Additional technical
information
is included for use by service personnel.
1 As new disc drives become available through new product development, the models supported by this interface may increase. Consult with
your
HP Sales and Service office if you need assistance in selecting disc drives for use with this interface.
1

2 Interface Installation and Configuration
Parts Supplied
The following items are supplied with the HP 98625A Disc Interface:
Item
Interface Card
Installation Manual
Select
Code Label
Part Number
98625-66501
98625-90000
7120-1957
Handling the Interface Card
The interface card contains components that are easily damaged by static electrical discharge
caused by improper handling. To minimize the risk of component damage, the interface
is
shipped in a special conductive plastic bag for protection. Do not remove the interface from the
bag until
it is to be installed. When installing the interface, be sure there is no opportunity to
create a static discharge. Hold the interface by the thumbscrews
and backplane cover while
removing
it from the bag, and avoid touching the circuitry on the card. Touch the metal surface
on the computer rear cover panel with one hand and maintain that contact while plugging the
interface into the computer with the other hand. After the interface
is seated into the backplane
connector, the risk of damage
is negligible. Whenever you need to remove the card from the
computer for service or system changes, keep the card
in its protective bag to prevent compo-
nent damage,
or place the interface on a work surface designed for servicing static-sensitive
electronic components
and assemblies.
Be careful to avoid touching the printed circuit edge connector fingers
on the interface. Finger-
prints promote contamination that can lead to unreliable operation. If
it becomes necessary to
clean the fingers, use a cotton swab
and isopropyl alcohol. Be sure to avoid the possibility of
electrostatic discharges while cleaning the connector fingers; both for safety,
and to prevent
component damage.

Interface Installation and Configuration 3
Installing Interface Cards in the 1/0 Backplane
The HP 9826/9836 computer has eight backplane slots that can be used for interface cards,
memory boards,
and other devices. However, only four slots can be used for interfacing to
external peripherals. The peripheral interface slots are located slightly below the threaded
fasteners that hold the interface retainer screws when the card
is inserted. If you insert the
interface into the wrong slot, the thumbscrews
in the interface cover cannot mate properly with
the threaded fasteners
in the rear panel. As successive interfaces are installed, the remaining
slots that are available for memory or other devices are reduced by
one for each interface
inserted.
To install the interface card, follow these steps:
1. Set the configuration switches on the interface as instructed in the Configuring the Inter-
facE~ section later in this chapter.
2. Be sure that the computer power switch is OFF.
3. Remove one or more backplane covers to locate an empty 110 slot. If none is available,
rearrange the memory boards as necessary. Memory boards can be installed in any slot in
the backplane. Be sure all boards are firmly seated in their respective backplane connec-
tors before replacing the covers.
If no slots are available, you must remove a memory board or other 110 card to free up
the necessary backplane space. If you remove a RAM memory board, it must be the
lowest address board
in the backplane. Refer to the Operating Manual for your computer
for information on how to identify the lowest-address memory card.
4. Slide the interface card into any available slot, component side
UP. Seat the card firmly
into its backplane connecter, then tighten the thumbscrews until they are finger tight. Be
sun~ a DMA card has been installed in the computer.
5. Replace any remaining covers that were previously removed, then use
an appropriate
cable to connect the interface to the first disc drive. Use HP 10833 cables to connect to
othler drives as explained later in this chapter.
6. Turn the computer and peripheral(s) on and operate as explained in the applicable
ope:rating manuals. If you encounter difficulty, contact your nearest HP Sales and Service
office.