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WD1002-27X
USER GUIDE

Introduction

The WD1002-27X controller is designed for use with RLL type hard disk
drives only. Consult your drive manual or contact the drive
manufacturer to determine the drive type.

DO NOT UNDER ANY CIRCUMSTANCES
CONNECT A RLL CONTROLLER
TO AN MFM DRIVE

The WD1002-27X is an easy to install, RLL controller, which
interfaces one or two Winchester disk drives to a single host
computer. It may be used as either a primary or secondary hard disk
controller in IBM PC XT or compatible systems.

Installation of the controller requires four steps: 1) Verifying
BIOS; 2) verifying jumper settings; 3) installing into the host
computer; 4) formatting the hard disk drives. To complete
installation you will need the following:

Two hard disk cables (3 if using 2 hard disk drives); RLL drive;
screwdriver; MSDOS Version 2.0 or later; *DEBUG utility; *FDISK
utility; *Format utility (*normally included with MSDOS)

Preparation of Controller

WARNING
HANDLE THE CONTROLLER BY THE ENDS OF THE BOARD
SOME OF THE CHIPS ARE STATIC SENSITIVE AND DAMAGE
MAY OCCUR IF THE BOARD IS INCORRECTLY HANDLED


Confirming BIOS

At location U12, please confirm that your WD1002-27X BIOS ROM is part
number 62-000094-followed by any three numbers (this BIOS ROM is
referred to as Western Digital's Super BIOS). If your controller has
any other BIOS, contact Technical Support at 1-800-777-4787.

Prepare Controller

Before you can install your WD1002-27X you will need to be certain
that the jumpers (small shorting plugs) are correctly set.














Drive 0
Data Cable 34pin Control Cable
J2 J1

J3
123
Drive 1 W8
Data Cable W4
1 1
2 W6 2 5
W9 3 6
BIOS 7
( 8 S1
U12 1 4
2 3
W3 2
1
A31 A1
WD1002-27X



Verify that the host computer contains at least a 135 watt power
supply. Verify that the jumper settings on the controller board are
correct. Modification of factory jumper settings is rarely
necessary. For jumper settings on W3, W4, W6 and W8, see Table 1.

Table 1
Jumper Settings

Pin
Jumper Connects Status
W3 Closed BIOS ROM enabled
Open BIOS ROM disabled
W4 1-2 Secondary Address 324 thru 327 hex
2-3 Primary Address 320 thru 323 hex (factory
setting)
W6 1-2 16 head disk drive configuration
2-3 8 head disk drive w/Reduced Write Current
configuration. (factory setting)
W8 1-2 Dual controller setting (CA00)
2-3 Primary Controller (factory setting) (C800)

Before setting the following jumpers, you will need to know the
parameters of your RLL drive. For your convenience, we have provided
a list of the most common drives. You may access the list by
returning to the previous menu.

IF YOUR DRIVE IS NOT LISTED, YOU WILL NEED TO OBTAIN THE PARAMETERS
FROM YOUR DRIVE MANUFACTURER OR MANUAL.

If your drive has 4 heads, a formatted capacity of 32 megabytes, and
fewer than 663 cylinders, the controller jumper settings should be
set as follows:













Table 2

Standard Jumper Settings - 30 Meg Drives/663 Cylinders or Less:

S1-1 Open S1-5 Closed
S1-2 Open S1-6 Closed
S1-3 Open S1-7 Open
S1-4 Open S1-8 Open (AT Mode)
W-9 Closed

Note: Table 2 jumper settings is the Translation Mode. Some
versions of DOS or other operating systems will not recognize the 26
sector per track feature of RLL drives. The Table 2 jumper settings
translate the configuration characteristics into a 17 sector per
track format recognized by the Operating System.

WITH TABLE 2 JUMPER SETTINGS, YOU MAY USE THE SIMPLIFIED FORMATTING
INSTRUCTIONS ON PAGE 4.

DRIVES WITH GREATER THAN 663 CYLINDERS

If your drive has more than 663 cylinders, it is recommended that you
use the jumper settings in Table 3. With drives having greater than
663 cylinders, you MUST use the Dynamic Formatting procedure. (See
page 7)

Table 3

S1-1 Open S1-5 Open
S1-2 Open S1-6 Closed
S1-3 Open S1-7 Open
S1-4 Open S1-8 Open (AT Mode)
W-9 Open



Preparation of Drive

WARNING
MAKE SURE COMPUTER IS TURNED OFF
AND POWER IS DISCONNECTED

There are 3 steps in preparing your drive to interface with the
WD1002-27X Controller.

1) Power for drive is supplied by host computer through an extra
connector from its power supply. Verify that the host computer
contains at least a 135 watt power supply.

2) The terminating resistor must be present only on the last hard
disk drive connected. If there are two drives, the terminating
resistor must be present on the second drive.














3) Drive Select: If the controller cable has a twisted portion
between two drive connectors, both drives must be jumpered for Drive
Select 2. If controller cable has no twisted portion, first drive
select should be 1, second drive select 2.

See your drive manual for drive preparation and installation
procedures.

Note: The hard disk drive cable is not the same cable used for
floppy disk drives.

Installation Into Host Computer


WARNING
MAKE SURE COMPUTER IS TURNED OFF
AND POWER IS DISCONNECTED

Installation of Controller into Host Computer

Remove blank expansion slot bracket and save for future use. The
screw will be used to hold the controller board into place.

INSTALL CONTROLLER INTO ANY AVAILABLE SLOT EXCEPT SLOT 8

Connect the 34-pin (wide control cable) connector to J1 on the
controller board. Make sure that Pin 1 of the cable connector goes
to Pin 1 on the controller board. Pin 1 of the cable connector is
typically located on the color coded side of the cable.

Connect the 20-pin (data cable) to J2 (Drive 0 Data Connector) on the
controller board. Make sure that Pin 1 on the cable is connected to
Pin 1 on the controller board.

If a second drive is being installed, connect the Drive 1 data cable
to J3.

Verify that the disk drive(s) is(are) installed properly. This
includes correct placement of drive select jumpers and drive
terminator installation. Refer to the disk drive installation manual
for further information. DO NOT USE THE RADIAL SELECT OPTION.

Install the drive(s) per manufacturer's instructions.






















CAUTION
WHEN ROUTING CABLES, BE CAREFUL NOT TO PINCH
THEM. CABLES MUST NOT GET CAUGHT BETWEEN THE
COVER AND THE BOARDS, NOR SHOULD THEY OBSTRUCT
ANY AIR FLOW PATH FROM FANS OR VENTS.