SEAGATE ST318404LW/LC - Manual

Cheetah 18XL Installation Guide

Model ST318404LW/LC and ST39204LW/LC SCSI interface disc drive

Publication Number:

75789507

, Rev. B, August 2000

Handling precautions/Electrostatic discharge protection

• Disc drives are fragile. Do not drop or jar the drive and handle the drive

only by the edges or frame.

• Drive electronics are extremely sensitive to static electricity. Keep the drive

in its antistatic container until you are ready to install it. Wear a wrist strap
and cable connected to ground. Discharge static from all items near or that
will contact the drive. Never use an ohmmeter on any circuit boards.

• Turn off the power to the host system during installation.
• Always use forced-air ventilation when operating the drive.
• Use caution when troubleshooting a unit that has voltages present.

• Do not disassemble the drive; doing so voids the warranty.

• Return the entire drive for depot service if any par t is defective.

• Do not apply pressure or attach labels to circuit board or drive top.

Electromagnetic compliance

See Safety and Regulatory Agency Specifications, p/n 75789512.

Drive characteristics

ST318404

ST39204

Formatted capacity ...................................... 18.352 Gbytes

9.176 Gbytes

Max. data blocks .......................................... 35,843,670

17,921,835

(222EE56h)

(111772Bh)

Cylinders/heads (user accessible) ................ 14,100/6

14,100/3

Disc rotation .................................................. 10,000 rpm

10,000 r pm

Operating voltages

+5V

+12V

+5V

+12V

Typical operating current ............................ 1.00

0.95

0.80

0.75

What you need

• Phillips screwdriver and four 6-32 UNC drive mounting screws

• Forced-air ventilation to provide adequate drive cooling
• An unused drive power connector (not applicable to LC models)

To operate at LVD transfer rates, you may also need an LVD-capable SCSI
host adapter, LVD I/O cable and active negation external terminator.

Multimode interface

This drive can operate in single-ended (SE) or low voltage differential (LVD)
mode. This multimode capability provides backwards compatibility so you
can use it with or without an LVD-capable host adapter. The primary benefits
of LVD technology include faster transfer rates, reduced power consumption,
increased allowable cable lengths, and improved device connectivity.

You can configure the drive to switch between SE and LVD modes automati-
cally or force it to operate in SE mode only. To configure this option, see Fig-
ure 2.

Note. To operate at the Ultra2 rates in LVD mode, all devices on the same

bus (cable) must be running in LVD mode. If you add any SE device to
the bus, all devices on that bus operate in SE mode.

Note. Some LVD host adapters provide an LVD connector and an SE con-

nector on the same host adapter to allow you to run SE and LVD
drives concurrently at their maximum capabilities. Check your SCSI
host adapter documentation. See Figure 3.

Caution. Do not mix LVD drives on the same bus with high voltage differen-

tial (HVD) devices–drive damage may occur.

Installation instructions

1.

Set the SCSI ID

Determine which SCSI IDs are already being used in the system and then
assign this disc drive a SCSI ID that isn’t already being used. Use the J6
connector located on the front of the drive to set the SCSI ID (see Figure 1).

• Most ST318404 drives are factory set with the SCSI ID set at 0. If this is

the only SCSI drive in your system and there are no other SCSI devices on
the daisychain, you can leave this drive’s SCSI ID set to 0 and proceed to
the next step.

• The host system’s SCSI controller usually uses SCSI ID 7.
• If you have an ST318404LC model drive, the host normally sets the ID

over the I/O interface, so you don’t need to worry about this step.

• Some systems provide a cable designed to connect to the J5 jumper block

on the drive to remotely set the ID. You can connect this cable to J5 and
use the host-provided remote switch to set the SCSI ID.

Figure 1.

Setting the SCSI ID

2.

Configure termination

If you are installing the drive in a system that has other SCSI devices
installed, terminate only the end devices on the SCSI bus (cable). This drive
does not have internal terminators or any other way of adding internal termi-
nation on the drive. You must provide external termination when termination
is required. This is normally done by adding an inline terminator on the end
of the cable. See Figure 3 for an illustration showing a system configuration
that uses an external terminator.

• Use active (ANSI SCSI-2 Alternative 2) single-ended terminators when

terminating a bus operating in single-ended mode.

• Use SPI-2-compliant active low voltage differential terminators when ter-

minating a SCSI Ultra2 bus operating in LVD mode.

• The host adapter is normally on the end of the bus and internally termi-

nated. You can configure your bus with another device on the end if you
remove termination from the host adapter.

3.

Configure terminator power

Terminators have to get power from some source. The default configuration
results in the drive not supplying termination power to the bus. You should
normally leave this drive set at this default unless your host system requires
the drive to supply termination power to the bus. To configure this drive to
supply termination power to the bus, place a jumper on J2 pins 1 and 2 as
shown in Figure 2.

• Host systems designed to use LC drives normally provide termination

power from the host adapter or other source. For this reason, LC model
drives cannot be configured to provide termination power to the bus.

SCSI ID = 0

(default)

Jumper Plug

(enlarged to
show detail)

J6

Drive
Front

Pin 1

Reserved

A

2

A

1

A

0

A

L

E

D

R

E

S

3

SCSI ID = 1

SCSI ID = 2

SCSI ID = 3

SCSI ID = 4

SCSI ID = 5

SCSI ID = 6

SCSI ID = 7

SCSI ID = 8

SCSI ID = 9

SCSI ID = 10

SCSI ID = 11

SCSI ID = 12

SCSI ID = 13

SCSI ID = 14

SCSI ID = 15

J1

DC Power

J1

68 Pin

SCSI I/O

Connector

Drive HDA

Rear

SCSI ID = 8

SCSI ID = 9

SCSI ID = 10

SCSI ID = 11

SCSI ID = 12

SCSI ID = 13

SCSI ID = 14

SCSI ID = 15

A

not used

3 A2 A1

SCSI ID = 0

SCSI ID = 1

SCSI ID = 2

SCSI ID = 3

SCSI ID = 4

SCSI ID = 5

SCSI ID = 6

SCSI ID = 7

A0

J5

Pin 1

4P

3P 2P

1P

PCBA

Pin 1

+5V

Ground

(default)