540MB SCSI Hard Disk  (250-4168)     Installation      Faxback Doc. # 2559

If you do not wish to install the drive yourself, contact your computer
dealer. A customer service technician will install the drive for you.

If you decide to install this drive on your own, please follow all
instructions carefully.

Keep the following cautions in mind:

* Static electricity can destroy integrated circuits. Be sure to
  discharge any built-up static electricity by touching a grounded,
  metal object before handling the drive or touching any of the computer
  logic boards.

* Carefully read the entire manual and the installation instructions in
  your computer user's guide before installing the drive.

* The drive does not require preventive maintenance. Do not remove or
  tamper with the sealed top cover.

Refer to your operating system and application documentation for specific
instructions about storing and accessing programs on hard disk.

PREPARING THE COMPUTER

Turn off the computer, and disconnect the power cords and the data
cables. Remove the computer cover as illustrated in your computer user's
guide.

PREPARING THE DRIVE

Before you install the drive, you must configure it for use in the
computer.

Carefully remove the drive from the protective packaging. Store the
packaging in a safe place for future use. The components used to prepare
the drive are shown in the illustration.

Configuring the jumpers on the drive enable or disable the functions of
the drive. A jumper is a clip that contains metal contacts. To install a
jumper, place it over two adjacent pins. This installation connects or
bypasses a circuit, enabling or disabling a function.

TERMINATING POWER

Whether terminating resistors should be removed from the drive depends
on the sequence of this drive relative to any other SCSI devices
installed in your computer.

The terminators on the drive can be removed as illustrated:

If the drive is the last device in a chain of SCSI devices or is the
only SCSI device in the system, leave the terminating resistors on the
drive. Leave the jumper on Pin Pair E5 to enable the +5V terminator
power to be supplied through the four-pin power cable. Remove the jumper
from Pin Pair E5 to disable the terminator power from the power cable,
so that the drive obtains terminator power through Pin 26 of the SCSI
interface cable.

If the device is not the last (or the only) SCSI device in a chain,
remove the three terminating resistors.

Drive ID

Jumper Pin Pairs E1, E2, and E3 set the drive ID. The default drive ID
is 0. Install the jumpers to indicate one of the following drive IDs:

PIN PAIR
┌────────────┬──────────────┬────────────┬──────────┐
│E1          │ E2           │ E3         │ DRIVE ID │
├────────────┼──────────────┼────────────┼──────────┤
│Open        │ Open         │ Open       │ 1 (1)    │
│Installed   │ Open         │ Open       │ 1        │
│Open        │ Installed    │ Open       │ 2 (2)    │
│Installed   │ Installed    │ Open       │ 3        │
│Open        │ Open         │ Installed  │ 4        │
│Installed   │ Open         │ Installed  │ 5        │
│Open        │ Installed    │ Installed  │ 6        │
│Installed   │ Installed    │ Installed  │ 7        │
└────────────┴──────────────┴────────────┴──────────┘
(1) Factory default setting.  (2) Usually reserved to tape drives.

DELAY SPIN OPTION

Jumper Pin Pair E4 enables or disables the delay spin option. When the
delay spin option is enabled (the default setting), the SCSI drive motor
spins up at power-on. When a jumper is installed on the Pin Pair E4, the
drive motor does not spin up at power-on.

SCSI PARITY CHECK

SCSI parity is always enabled in both directions on the SCSI bus, from
and to the drive.

ATTACHING THE 5 1/4" DRIVE BAY MOUNTING BRACKETS

You might need to attach mounting brackets if you install the 3 1/2"
drive in a 5 1/4" drive bay. Refer to your computer user's to determine
whether the brackets are required for your computer chassis. Brackets
and other mounting hardware are available from your computer dealer. Use
the two machine screws to secure a mounting bracket to each side of the
drive as shown.

INSTALLATION

After preparing the drive, install the drive in your computer. Refer to
your computer user's guide for the installation procedure appropriate
for your chassis type.

CONNECTING THE DRIVE INTERFACE

To complete the installation, connect the drive to the drive interface,
using the cable shown in the following figure. If your computer or SCSI
adapter kit does not contain the interface cable, you can obtain the
cable from your computer dealer. The drive end of the cable is the end
with two connectors positioned nearest each other, and the interface end
is the end with only one connector.

1. Connect the interface end connector to the cable connector on the SCSI
   interface. If the interface is built into the computer, it will be on
   the main logic board. See the computer user's guide for details. If
   the SCSI interface adapter has been installed, see the adapter
   installation guide for connection instructions.

NOTE: The cable connectors are keyed so that they connect only one way.
Do no force the connections.

2. Connect the appropriate drive connector to the hard drive. Be sure
   that Pin 1 orientation is correct.

   If this is the first hard drive installed, attach the outer drive
   connector to the hard drive.

   If this is the second hard drive installed, attache the middle drive 
   connector to the hard drive.

3. Connect a four-pin power cable to the hard drive. These power cables
   are identical; any power cable can be connected to any internal drive.

4. After you complete the installation for the drive and any other
   internal options that you are adding at this time, carefully put the
   cover back on the computer.

5. Reconnect all peripheral cables to the appropriate connectors on the
   back of the computer.

6. Reconnect the power cord.


(smm/jej-05/11/94)