Seagate ST118202LW-LC User Manual

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Cheetah 18

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Disc Drive

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ST118202LW/LC

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Installation Guide

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Contents

Preface..................................................................................... 1

Electrostatic discharge protection ............................................ 1

Important safety information and precautions................... ....... 2

Wichti g e Si c h er h e its h in w ei se . ... ......... ... .......... ......... ... .......... ... 4

Regulatory agency compl iance........... ........ .. ........ ...................7

Seagate Technology support services...................................... 9

General description ................................................................ 15

Initial se tup informa tion .......... .......... .. .......... .......... .. .......... .... 19

Kühlung des Systems............................................................. 29

Installa ti on des Laufwerkes und Anschluß der Kabel.............31

LW drives secti on .. ... ......... ... .......... ......... ... .......... ......... ... ...... 3 9

LC drives section.................................................................... 45

©1997, 1998 Seagate Technology, Inc. All right s reserved
Publication Number: 83329250, Rev. A
March 1998

Seagate, Seagate Technology, and the Seagate logo are regis­tered tra dem arks of Seagate Technology, Inc. Cheetah, SeaFAX,
SeaFONE, SeaBOARD, and SeaTDD are eit her trademarks or
registered trademarks of Seagate Technology, Inc. or one of its
subsidiaries. All other tradem arks or registered trademarks are
the property of their respective owners.

No part of this publication may be reproduced in any form with-

out written permission from Seagate Technology, Inc.

Cheetah 18 Installation Guid e, Rev. A 1

Preface

This manual contains information for users of the Seagate®

Cheetah 18 SCSI disc drives. It provides support services, per-

formance specifications, and initial setup infor mation. Additional

infor mat ion i s availa ble in the

number 8332926 0). Contac t your Seagate sal es repres enta tiv e if

you need to order t his publication.

Electrostatic discharge protection

Caution.

All drive electronic assembli es are sensitive to static electricity,

due to the electrostatically sensitive devices used within the

drive cir cui try. Although some devices such as metal-oxide semi-

conductors are extremely sensitive, all semiconductors, as well

as some resi stors and capacit ors, may be damaged or deg raded

by exposure to static electricity.

Electrost atic damage t o electr onic de vices may be caus ed by the

direct discharge of a charged conductor or by exposure to the

static fields surrounding charged objects. To avoid damaging

drive electronic assemblies, observe the following precautions

when installing or servicing the drive:

• Ground yourself to the drive whenever the drive electronics
are or will be expos ed. Connect yourse lf to ground with a wrist
strap (Seagat e par t number 12263496). Connection may be
made to any grounded metal assembly. As a general rule,
remember that you and the drive electronics must all be
grounded to avoid potentially damaging static discharges.

Removal of circuit boards by personnel not perform­ing depot repair will damage components and may
void the war ranty.

Cheetah 18 Product Manual

(part

2 Cheetah 18 Instal lation Guide, Rev. A

• Turn off the power before removing or installing the DC power
cable.

• Do not remov e any circuit boards from the drive.

• Never use an ohmmeter on any circuit boards.

• When installing th e drive on a carrier or t ra y, discharge the car­rier or tray pr io r to ins e rting it into th e sy st e m.

Important safety information and precautions

Caution.

Use proper safety techniques for safe, reliable operation of this
unit.

The procedures in this manual and labels on the unit contain
warnings and cautions that must be carefully read and followed
to minimize or eliminate the risk of personal injury. The warnings
point out conditi ons or practices that may endanger you or oth­ers. The cautions point out conditions or practices that may dam­age the unit, poss ibly making it unsafe for use.

Always observe the following warnin gs and precautions:

• Follow all cautions and warnings in the procedures.

• Use sound safety practices when operating, installing, or
removing the uni t.

• Use caution when troubleshooting a unit that has voltages
present. Turn off power to the unit before removing it.

• Ensure that the internal temperature of the rack or cabinet
does not exceed the limits defined for the drive when t he drive
is mounted in an equipment rack or cabinet. When units are

Use forced-air ventilation when bench-testing the
drive to ensur e proper cooling of driv e com ponents.

Cheetah 18 Installation Guid e, Rev. A 3

stacked ver tically, pay special attention to the top where tem­peratures ar e usually highest.

• Follow the precautions listed above in “Electrostatic discharge
protection.”

• Do not remove any circuit boards from the drive. Return the
entire drive for depot repair if any circuit board is defective.
Removal of circuit boar ds by personnel not performing depot
repair will damage components and may void the warranty.

• Do not separate the head and disc assembly (HDA) from the
PCB. Return the entire drive for depot repair if the HDA is
defective.

• Do not attempt to disassemble the HDA. It is not field repair­able. If the sealed HDA is opened by personnel not performing
depot repair, this will damage components and void the
warranty.

As a component, this drive is designed to be installed and oper­ated in accordance with UL1950, EN60950, CAN/CSA C22.2
950-95, and VDE0805.

Seagate takes all reasonable steps to ensure that its products
are certifiable to currently accepted standards. Typical applica­tions of these disc drives include customer packaging and sub­system design. Safety agencies conditionally certify component
assemblies, such as the Cheetah disc drive, based on their final
acceptability in the end-use product. The subsystem designers
are responsible for meeting these conditions of acceptability in
obtaining safety-regulatory agency compliance in their end-use
products and for certifying where required by law. A necessary
part of meeting safety r equirements is the provision for overcur­rent protection on dr ive SELV supply voltages.

4 Cheetah 18 Instal lation Guide, Rev. A
This unit is a component par t and as such is not meant to com-

ply with FCC or simil ar national requirements as a stand-alone
unit. Engineering radiated emissions test results are available
through the Seagate Safety Depar tment to assist the subsystem
designer.

Wichtige Sicherheitshinweise

Vorsicht.

Fremdbelüftung vorzusehen, um eine ausr eichende Kühlung der
Laufwerkkomponenten sicherzustellen.

Verwenden Sie geeignete Sicherheits- um den sicheren, zuver­lässigen Betrieb dieser Einheit zu gewährleisten.

Die Verfahren in diesem Handbuch und die Aufkleber auf dem
Gerät enthalten Warn- und Vorsichtshinweise. Diese Hinweise
sind sorgfältig durchzulesen und zu beachten, um das Risiko
von Verletzungen auf ein Mindestmaß zu beschränken oder
ganz zu vermeiden. Die War nhinweise machen auf Situationen
oder Praktiken aufmerksam, die Sie oder andere gefährden
könnten. Die Vorsichtshinweise machen auf Situationen oder
Praktiken aufmerksam, die Einheit beschädigen können, so daß
deren Gebrauch mit Risiko behaf tet ist.

Die Warn- und Vorsichtshinweise sind nicht allumfassend! Es ist
uns einfach nicht möglich, alle Wartungsmethoden oder die
eventuellen Risiken jeder Methode zu kennen, zu beurteilen und
Sie entsprechend zu beraten. Aus di esem Grund haben wir auf
eine derartige umfassende Beurteilung verzichtet. Falls Sie ein
hier nicht beschriebenes Verfahren oder Werkzeug verwenden,
stellen Sie zuerst sicher, daß das gewählte Verfahren weder Ihre
persönliche Sicherheit noch die Leistung der Einheit gefährdet.

Beim Testen des Laufwerks auf dem Prüftisch ist

Cheetah 18 Installation Guid e, Rev. A 5
Beachten Sie in jedem Fall die folgenden Warn-und Vorsicht-

shinweise:

• Beachten Sie alle Warn- und Vorsichtshinweise in diesem
Handbuch.

• Treffen Sie beim Betrieb, bei der Installation oder bei der
Entfernung der Einheit angemessene Sicherheitsvorkehrun­gen.

• Wenn eine Einheit unter Spannung steht, gehen Sie bei der
Fehlerdiagnose besonders vorsichtig vor. Schalten Sie die
Einheit au s, bevor Sie mit den Ins tal lations-un d Entfernungsar­beiten beginne n.

• Wenn das Laufwerk in einem Einbaugestell oder Gehäuse
montiert ist, sorgen Sie dafür, daß die Temperatur im Inneren
des Gestells oder Gehäuses die für das Laufwerk vorgege­benen Grenzwerte nicht übersteigt. Wenn Einheiten vertikal
übereinander betestigt werden, achten Sie besonders auf den
oberen Stapelbereich, da dor t die Temperatur gewöhnlich am
höchsten ist.

• Befolgen Si e die oben unter “Electrostatic Discharge Protec­tion” angegebenen Sicherheitsmaßnahmen.

• Nehmen Sie keine Platinen aus dem Laufwerk. Wenn eine
Platine defekt ist, muß das gesamte Laufwerk zur Reparatur
eingeschickt werden. Die Herausnahme von Platinen durch
andere Personen als die für die werkseitige Reparatur zustän­digen kann zu einer Beschädigung der Komponenten und
Erlöschen des Garantieanspruchs führ en.

6 Cheetah 18 Instal lation Guide, Rev. A

• Die vormontierte Kopf- und Festplatteneinheit (HDA) nicht aus
dem Laufwerkgehäuse nehmen! Falls die HDA beschädigt ist,
schicken Sie das gesamte Laufwerk zur Reparatur ein.

• Die HDA ist nicht vor Or t reparierbar und darf nicht auseinan­dergenommen werden! Öffnen der versiegelten HDA durch
andere Personen als die für die werkseitige Reparatur zustän­digen hat eine Beschädigung der Komponenten und
Erlöschen des Garantieanspruchs zur Folge.

Als Teil komponente is t dieses Laufwerk f ür die Ins tallation und
den Betrieb in Übe reinstim mung mit UL 19 50, EN6 0950, C AN/
CSA C22.2 950-95 und VDE0805 vorges ehen.

Seagate ist ständig bemüht, die Zulassungsfähigkeit von
Seagate-P rodukten im Rahme n der gegenw är tig geltend en
Standa rds z u gewäh r leist en. Zu den ty pisch en An wend unge n
dieser Festplattenwerke zählen Systemeinbau durch den
Kunden und die K on strukti on von Unter systemen. Sicherh eitsbe ­hörden gewähren eine bedingte Zulassung für Komponenten wie
das Cheetah-Festplattenlauf werk vorbehaltlich der endgültigen
Zulasssun g im E ndprod ukt. De signer von Unters ysteme n sind
dafür ver antwortlich, die Voraussetzungen für die Einhaltung
sicherheits- oder aufsichtsbehördlicher Vorschriften in ihren
Endprodukten und - falls ge setzlich vorgeschrieben - für die
Zulass ung zu sc ha ffen. Eine Gr un dvorau sset zu ng zu r Ei nha l­tung der Sicherheitsanforderungen ist die Bereitstellung eines
Überlastschutzes für die SELV-Versorgungsspannungen des
Laufwerks.

Dieses Gerät ist eine Baugruppe und unterliegt als solche nicht
den Anforderungen der FCC oder ähnlicher nationaler Behörden
für eigenst ändige Geräte. Technische Testergebnisse zu elektro-

Cheetah 18 Installation Guid e, Rev. A 7
magnetische Str ahlung si nd für Design er von Unte rsyst emen auf

Anfrage von der Seagate-Sicherheitsabteilung erhältlich.

Regulatory agency compliance

Electromagnetic susceptibility

As a component assembly, the drive is not required to meet any
susceptibility performance requirements. It is the responsi bility o f
those integrating the drive within their systems to perfor m those
tests required and design their system to ensure that equipment
operating in the same system as the drive or external to the sys­tem does not adversely affect the perfor mance of the drive. See
DC power requirements on page 18.

Electromagnetic compliance

Seagate uses an independent laboratory to confirm compliance
to the directives/standard(s) for CE Marking and C-Tick Marking .
The drive was tested in a repre sentative system for typical appli­cations. The selected system represents the most popular char­acteristics for test platforms. The sy stem configurations include:

• 486, P entium, and P owerPC microprocessors

• 3.5 -inch f loppy disc dri ve

• Keyboard

• Monitor/display

• Printer

• External modem

• Mouse

Although the test system with this Seagate model complies to
the directives/standard(s), we cannot guarantee that all systems
will comply. The computer manufacturer or system integrator

8 Cheetah 18 Instal lation Guide, Rev. A
shall confirm EMC compliance and provide CE Marking and C-

Tick Marking for their product.

Electromagnetic compliance for the European Union

If this model has the CE Marking it complies with the European
Union requirements of the Electromagnetic Compatibility Direc­tive 89/336/EEC of 03 M ay 1989 as amended by Directi ve 92/31/
EEC of 28 April 1992 and Di rective 93/68/EEC of 22 July 1993.

Australian C-Tick

If this model has the C-Tick Marking it complies with the Austra­lia/New Zealand Standard AS/NZS3548 1995 and meets the
Electromagnetic Compatibility (EMC) Framework requirements
of Australia’s Spectrum Management Agency (SMA).

Cheetah 18 Installation Guid e, Rev. A 9

Seagate Technology support services

Presales support

To determine which Seagate products are best suited for your
specific application, cont act us about configuration and compati­bility and for current product availabili ty. You can leave a voice
message after business hours or send an e-mail message—we
reply during b u siness hours.

Disc Drives 405-936-1210 Fax: [phone]

A.M

(8:00
e-mail: [e-mail]

.

to 12:15 P.M., 1:30 P.M. to 6:00

Tape Product s 1-800-626-6637 or 714-641-2500

A.M

Fax: [phone]

e-mail: [e-mail]

Note.

You can purchase select tape products and tape acces­sories through Seagate Express 24 hours daily by calling
1-800-531-0968 or by faxing your order to 972-481-4812.

(6:00

.

to 5:00

T e c hnical support services

If you need assistance installing your drive, consult your dealer.
Dealers are familiar with their unique system configurations and
can help you with system conflicts and other technical issues. If
you ne ed additional assistance with you r Seagate
Seagate products, use one of the Seagate technical support ser­vices list ed below.

SeaFONE® 1-800-SEAG ATE

Seagate’s 800 number (1-800-732-4283) allows toll-free access
to automated self-help services, providing answers to commonly

P.M

.

, central time, M-F)

P.M

.,

pacific time, M-F)

®

drive or other

10 Cheetah 18 Installation Guid e, Rev. A
asked questions, troubleshooting tips, and specifications for disc

drives and tape drives. This service is available 24 hours daily
and requires a touch-tone phone. International callers can reach
this automated self-help service by dialing 405-936-1234.

Online services

Using a modem, you can obtain troubleshooting tips, free utility
programs, drive specifications and jumper settings for Seagate’s
entire product line. You can also download software for installing
and analyzing your drive.

SeaNET

You can obtain technical information about Seagate products
over the Inte rne t fro m Se aga te’s World Wi de We b hom e pa ge

(http://www.seagate.com)
ftp.seagate.com)

DiscSupport @ Seagate.com

to

Seagate.com

. You can also send E-mail with y our questions

.

or Seagate’s ftp server

TapeSupport @

or

Seagate CompuServe forum

Online technical support for Seagate products is available on
CompuServe. To access our technical support forum, type

seagate

SeaBOARD. In addition, you can type questions or browse
through previous questions and answers on the forum mes­sages.

. This f orum provides information s imi lar to that found on

SeaBOARD®

SeaBOARD is a computer bulletin board system that contains
information about Seagate disc and tape drive products and is
available 24 hours daily. Set your com munications software to
eight data bits, no parity, and one stop bit (8-N-1).

(ftp://

go

Cheetah 18 Installation Guid e, Rev. A 11

Location Phone number

Austral ia 61-2-9756-2359
France 33 1-48 25 35 95
Germany 49-89-140-9331
Taiwan 886-2-2719-6075
Thailand 662-531-8111
UK 44-1628-478011
USA Disc: 405- 936-1600; Tape: 405-936-1630

FAX services

SeaFAX®

You can use a touch-tone telephone to access Seagate’s auto­mated FAX system to receive technical support information by
return FAX. This service is a vailable 24 hours daily.

Location Phone number

Austral ia 61-2-9756-5170
Germany 49-89-1430-5102
UK 44-1628-894084
USA Disc: 405-936-1620; Tape: 405-936-1640

Technical support FAX

You can FAX questions or comments to technical support spe­cialists 24 hours daily. Responses are sent during business
hours.

Location Phone number

Austral ia 61-2-9725-4052
France 33 1-46 04 42 50

12 Cheetah 18 Installation Guid e, Rev. A

Location Phone number

Germany 49-89-1430-5100
Hong Kong 852-2368 7173
Japan 81-3-5462-2979
Korea 82-2-556-4251/7395
Singapore 65-488-7528
Taiwan 886-2-2715-2923
UK 44-1628-890660
USA Disc: 405-936-1685; Tape: 405-936-1683

Direct-support services

Technical support

For one-on-one help, you can talk to a technical support special­ist during local business hours. Before calling, note your system
configuration and drive model number (ST

Location Phone number

Australia 61-2-9725-3366 (9:00

time, M–F)

France 33 1-41 86 10 86 (9:30

2:00

P.M

.

to 5:00

P.M

Germany Disc: 49-89-140-9332; Tape: 49-89-140-9333

(9:30

A.M

.

to 12:30

P.M

M–F)
Hong Kong 852-2368 9918
Kore a 82-2-531-5800 (9:00

P.M

.

to 6:00

Singapore 65-488-7584 (9:00

to 5:00

P.M

P.M

.

, M–F)

.

, M–F)

A.M

Taiwan 886-2-2514-2237

A.M

A.M

.

, M–F)

.

, 2:00

A.M

.

to 12:00

.

to 12:00

xxxx

.

to 5:00

.

to 12:30

P.M

).

P.M

.

to 4:00

P.M

P.M

.

.

, eastern

P.M

.

,

P.M

.

, 1:00

, 2:00

P.M

.

,

.

Cheetah 18 Installation Guid e, Rev. A 13

Location Phone number

UK 44-1628-894083 (10: 00

2:00

P.M

.

to 5:00

P.M

.

, M–F)

A.M

.

to 1:00

P.M

.

,

USA Please dial 1-800-SEAGATE or 405-936-1234

for the speci fi c product telephone number.

(8:00

A.M

.

to 12:15

P.M

.

, 1:30

P.M

.

to 6:00

P.M

.

,

centra l time, M–F)

SeaTDD™ 405-936-1687

Using a telecommunications device for the deaf (TDD), you can
send questions or comments 24 hours daily and exchange mes-

A.M

sages with a technical suppor t specialist between 8:00
12:15

P.M

. and 1:30 P.M. to 6:00

P.M

.

(central time) Monday

.

to

through Friday.

Customer service centers

Seagate direct OEM, Distribution, and Systems Integrat or cus­tomers should contact their Seagate service represent ative for
warranty information. Other customers should contact t heir place
of purchase. Seagate offers comprehensive customer support
for all Seagate drives. These services are available worldwide.

Location Phone number FAX number

Asia Pacific and Australia 65-485-3595 65-488-7503
Europe, Middle East,

and Africa 31-2031-67300 31-20 65-34320
Japan 81-3-5462-2904 81-3-546 2-2979
USA 1-800-468-3472 405-949- 6740

Other Americas (Braz il ,

Canada, Mexico) 405-949-6706 405-949-6738

14 Cheetah 18 Installation Guid e, Rev. A

Location Phone number FAX number

Manufacturer’s representatives

Brazil

MA Informatica 55-21-516-6649 55-21-516-5280
Canada

Memofix

Adtech

905-660-4936
905-812-8099

905-660-8738
905-812-7807

1-800-624-9857

Mexico

Abicom Seamax

SA DE CV 525-546-4888 525-546-4888

Southern Europe

Caesar Italia 39-688-18149 3 9-688-02103

Cheetah 18 Installation Guid e, Rev. A 15

General description

Cheetah 18 SCSI disc drives are high-speed, random-access
digital-data storage devices capable of operating in single-en ded
(SE) or low volt age differ ential (LVD) modes.

These two modes are offered to allow you to use this dr ive in
systems that use the traditional SE technology or to use it in
LVD-capable systems. Refer to page 20 for additional informa­tion about LVD technology.

The drive is a component for installation in an enclosure
designed for the drive. This is often a rack within the system or
an external enclosur e desi gned to house one or more di sc driv es
or other peripheral units. In either case, the disc drive must
receive adequate cooling (refer to “Providing adequate cooling”)
and it must be sufficiently grounded and shielded from emis­sions. The
contains guidelines for a properly designed enclosure.

Attention.

Cheetah 18 Product Manual

This high per formance Chee tah disc drive must have
proper power and cooling for reliable operation.

(part number 83329260)

16 Cheetah 18 Installation Guid e, Rev. A

Figure 1. Cheetah 18 family drive (ST118202LW shown)

Cheetah 18 Installation Guid e, Rev. A 17

Characteristics ST118202LW/LC

Interface Ultra2 SCSI
Capacity

Unformatted (Gbytes)
Formatted (Gbytes)

2

22.54

18.21

Recording

Cylinders (us er)
Read/write data heads
Avg bytes/t ra ck

Access time

3

Average read (msec)
Average write (msec)

6,962
24
104,840-159,008

5.9

6.7

Disc rotation

RPM
Average latency (msec)

10,025

2.99

Synchronous data transfer rate

Maximum instantaneous (Mbytes/sec)

40 (SE mode)
80 (LVD mode)

Asynchronous data transfer rate
Maximum instantaneous (2 bytes wide)

10.0

(Mbytes/sec)
Multi-segmented cache (kbytes) 1,024 standard

4,096 optional

1. Also operates per SCSI-1/SCSI-2/SCSI-3 protocols.

2. The specified formatted capacities are calculated with the standard

OEM sector size (512 bytes per logical block) and sparing.

3. Includes on-board controller overhead.

1

18 Cheetah 18 Installation Guid e, Rev. A

ST118202LW/LC

Single-ended (SE)
mode

1

DC power requirements (±5%)

Maximum start current
Maximu m operating current
Average idle cur re nt

1. For more detailed power informa tion, refer to the Cheetah 18 Product

Manual, publication number 83329260.

+5 V+12 V +5 V+12 V

0.89A

0.88A

0.72A

2.5A

1.22A

0.98A

Low voltage
differential (LVD)
mode

0.90A

0.95A

0.74A

2.5A

1.22A

0.98A

Cheetah 18 Installation Guid e, Rev. A 19

Initial setup information

The general information beginning on t his page applies to all of
the Cheetah 18 drive models. Af ter reading the general informa­tion topics, refer to the appropriate drive-specific section listed
below for additional infor mation about configuring and installing
your particular model.

Drive models Page

ST118202LW 39
ST118202LC 45

General information

The foll owing general information topics are discussed:

• Single-ended and low voltage differential modes

• SCSI ID jumpers

• Drive termination

• Terminator power

• Interf ace drivers and dat a path width notes

• Other applica ble jumper options

• Providing adequate cooling

• Mounting the dr ive and connecting cables

• Formatting t he drive

1

This mounting procedure does not apply to “LC” model drives.
To mount an “LC” drive, plug the drive into the system’s single
connector attachment (SCA) position on the system’s back
panel.

1

20 Cheetah 18 Installation Guid e, Rev. A

Single-ended and low voltage differential modes

This drive incorporates two different transceivers to allow you to
use it in traditional systems which may use single-ended (SE)
drivers and rec eivers, or to use it in lo w voltage differential (LVD)
capable systems which use LVD drivers and receivers.

You can configure the drive to switch between SE and LVD
modes automatically or force it to operate in SE mode only as
described later in this guide.

LVD technology enhances parallel SCSI I/O performance,
reduces power consumption, increases allowable cable lengths,
and improves device connectivity be yond SE capabilities.

Note.

To operate at the Ultra2 SCSI rates in LVD mode, all
devices on th e same bus must be running i n LVD mode. If
you add any single-ended device to a bus that is operat­ing in LVD mode, all devices drop back to operating in
single-ended mode. This eliminates the possibility of
reaching Ultra2 SCSI transfer rates.

Warning.

Do not mix LVD drives on the sam e daisy chain with
devices having high voltage differential (HVD) inter­face circuits.

SCSI ID jumpers

Each device on the SCSI chain must have a unique SCSI ID.
The host system’s SCSI controller usually uses the ID that has
the highest priority interrupt in the SCSI I/O system. This is
always ID7. ID0 has the lowest priority in an 8-bit I/O system. ID8
has the lowest priority in a 16-bit I/O system. The lower priority
SCSI IDs are nor mally used for other SCSI devices such as this
Cheetah disc dr ive.

Cheetah 18 Installation Guid e, Rev. A 21
Note. Most SCSI controllers (host adapters) allow you to skip a

SCSI ID. For example, you can have ID0, ID1, and ID3
(skipping ID2). Other controllers do not allow this so be
sure to refer to your system or control ler user’s m anual
for details about its requirements for proper SCSI device
installat io n .

Note. This drive is SCAM (SCSI Configured Auto Magically)

compliant. If the system into which you are installing this
drive requires SCAM compliant drives, you do not need
to be concerned about the drive ID jumper settings, as
the system autom atically assigns your new drive the ID it
wants it to have. The system may or may not use the
existing drive ID jumper settings. Setting the drive ID
doesn’t hurt anything, but is not necessary in a SCAM
compliant system.

Most Cheetah disc drives are factory set with the SCSI ID set at

0. To change the SCSI ID, refer to the appropriate drive section
for your model.

If, after completing the installation process, the drive’s LED does
not show on/off activity when the host is trying to communicate
with the drive, a duplicate SCSI ID may be the problem. If this is
the case, change the ID so that each device on the SCSI chain
has its own unique ID. Also check your system or controller
user’s manual to ensure that you have not violated its SCSI ID
numbering recomm endations.

22 Cheetah 18 Installation Guid e, Rev. A

Drive termination

If you are installing a Cheetah drive in a system that has other
SCSI devices installed, terminate only the end devices on the
SCSI chain. A SCSI “device” is any disc drive, scanner, tape
backup unit, or other piece of hardware connected to your sys­tem using the SCSI bus.

Note.

Use active (ANSI SCSI-2 Alternative 2) single-ended ter­minators when terminating a bus operating in single­ended mode. Use SPI-2-compliant active low voltage dif­ferential terminators when terminating a SCSI Ultra2 bus
operating in LVD mode.

The top example in Figure 2 shows an i nternal hard disc at one
end of the SCSI bus with the SCSI controller at the other end
(both are terminated). The bottom example shows two additional
SCSI devices connected externally—this means the SCSI con­troller is no longer on the end of the SCSI chain and should not
be terminated.

Note.

Some controller s prefer to remain terminated even if they
are in the middle of the chain. Also, some controllers treat
the internal and external chains as separate logical
buses. This means you may need to terminate both the
first and last devices on both logical buses to achieve
proper termination. If necessary, refer to your system or
controller documentation to see how this is handled in
your particular system.

These drives do not have on-bo ard t erminators, so you m ust ter­minate external to the drive when termination is required. For
ST118202LC drives, this is normally accomplished by terminat-

Cheetah 18 Installation Guid e, Rev. A 23
ing the bus at the backpanel. For ST118202LW dri ves, use an in-

line t e rmina tor on t h e cable.

Internal SCSI cable

Internal

SCSI device

Internal

SCSI device

Internal SCSI cable

Internal

SCSI device

Internal

SCSI device

Terminate

Controller

Terminate

Controller

External

SCSI
cable

External

SCSI device

External

SCSI device

Figure 2. SCSI bus termination

T erminator po wer

You usually will not need to change this option and can normally
leave the drive conf igured as it was shi pped from the factory. For
information about how to change the terminator power opti on on
your driv e, refer to the appropriate driv e-specific section.

I/O circuits and data path widths

• These drives can be used in single-ended or low voltage differ-

ential interface systems; however, do not attempt to mix these

drives on the same daisy chain with high voltage differential

devices. The circuits are not compatible and drive damage

may occur.

• These drives have a “wide” (16-bit) SCSI data bus rather than

the standard (non-wide) 8-bit SCSI data bus; however, you

24 Cheetah 18 Installation Guid e, Rev. A

can use these wide drives on a st andard (non-wide) 8-bit data

bus if you pr ovide proper termination to the upper 8-bit data

lines. This is often referred to as providing “high-9 termina-

tion.”
Figures 3, 4, and 5 show typical drive conne cti ons.
The following table lists the maximum cable lengths and num ber

of devices using single-ended and LVD I/O circuits allowed on a
daisy-chain cable for 10, 20, and 40 Mtransfers/sec I/O data
transfer ra te s.

T able 1. Cable characteristics for SE and LVD circuits

SCSI
driver
type

I/O transfer rate
(Mtran sfers/s)

Maximum
number of
devices on
bus

Maxi mum ca ble
length allowed

SE 10 16 6 meters (19.7 ft.)
SE 20 4 3 meters (9.8 ft. )
SE 20 8 1.5 meters (4.9 ft.)
LVD 40 16 12 meters (39.4 ft .)

A maximum of 16 devices can be connected on a 16-bit wide
data bus.

Cheetah 18 Installation Guid e, Rev. A 25

Figure 3. 68-pin I/O connection to drive (LW model)

Figure 4. 80-pin I/O connection to drive (LC model)

26 Cheetah 18 Installation Guid e, Rev. A

“LW” Model

Drive

Note:

Do not mix
“LW” and “WD”
model drives
on the daisy
chain.

SCSI ID 1

[2]

SCSI ID 0

Terminator

2 through X
SCSI devices [1]

Pin 1

(check your

adapter for Pin 1 location)

SCSI ID 7

Terminated

Host Adapter

PCB

[1] “X” means up to 15 or the maximum allowable number of devices on

the SCSI bus. See system documentation and Table 1.

[2] Ex ternal terminat or. Used only on end “LW” drive. Use only SPI-2-

compliant active LVD terminators on SCSI Ultra2 buses.

Figure 5. Multiple-drive connection to host adapter

Cheetah 18 Installation Guid e, Rev. A 27

80-pin

SCSI I/O

Connector

Pin 1

J2

J6

Note. This drive model plugs directly into a backplane connec-

tor and therefore does not use cables.

Figure 6. Drive model “LC” with single 80-pin I/O and

power connector

28 Cheetah 18 Installation Guid e, Rev. A

Providing adequate cooling

The enclosure design must ensure adequate cooling for the
drive. The maximum ambient temperature al lowed is 50°C.

The drive’s product manual (83329260) describes how to evalu­ate the air-flow design. The evaluation consists of ensuring that
the case temperature of certain critical components remains
within acceptable limits during drive operation.

We recommend orienting the drive or directing the air flow in a
way that creates the least amount of air-flow resistance while
providing air flow above the circuit boards and around the head
and disc assembly (HDA). Also, choose the shortest possible
path between the air inlet and exit. This minimizes the distance
traveled by air that is heat ed by the drive and by other nearby
heat source s.

Figure 7 shows two design approaches with one or more fans
used to generate air flow. The air-flow patterns can be created
by the fans either pushing or drawing air. The overall flow pattern
can be directed from front to back, back to front, or side to side.

Cheetah 18 Installation Guid e, Rev. A 29

Kühl ung des Systems

Die Gehäusekonstruktion muß eine ausrei chende Kühlung des
Laufwerkes gewährleisten. Die Umg ebungstemperatur darf max­imal 50°C betragen.

Die Produkthandbuch Cheetah 18 (Dokument 83329260)
enthalten Anweisunge n zur Beur teilun g der Luftstr omkonstruk­tion. Die Beurteilung muß sicherstellen, daß sich die Gehäuse­temperatur bestimmter kritischer Komponenten bei
Laufwerkbetrieb innerhalb zugelassener Grenzen hält.

Wir empfehlen, das Laufwerk so zu orientieren oder den Luft­strom so zu l enken, d aß d er ger ingste L uftst romwiders tand
erzeugt wird und gleichzeit ig ein Luftstrom über den Platinen
und um die Kopf- und Festplatteneinheit (HDA) gegeben ist.
Wählen Sie einen möglichst kurzen Weg zwischen Lufteinlaß
und -auslaß. Dadurch wird die Strecke, die die vom Laufwerk
und anderen nahegelegenen Hitzequellen aufgewärmte Luft
zurücklegt, auf ein Minimum beschränkt.

Abbildung 7 zeig t zwe i Konstr ukti onsm öglic hkeite n, bei dene n
ein oder mehrere Lüfter den Luftstrom erzeugen. Der Luftstrom­verlauf wird durch die Lüfter gesteuert, die entweder Luft einbla­sen oder abzie hen . Genere ll kann d er Lu ftstrom entweder von
vorne nach hinten oder von hinten nach vorne verlauf en.

30 Cheetah 18 Installation Guid e, Rev. A

.

Above unit

Note. Air flows in the direction shown (back to front)
or in reverse direction (front to back)

Above unit

Note. Air flows in the direction shown or
in reverse direction (side to side)

Under unit

Figure 7. Suggested air flow
Abbildung 7. Empfohlener Luftstromverlauf

Under unit

Cheetah 18 Installation Guid e, Rev. A 31

Mounting the drive and connecting cables

Do not touch the connector pins or any components on the con­trol board without observing static-discharge precautions.
Always handle the drive by the frame only.

The drive may be mounted in any orientation (horizontally, verti­cally, and any combination thereof); however, you must ensure
that the drive receives adeq uate air flow for cooling.

1. Mount the drive to the host system’ s chassis using four 6-32

UNC screws. Two mounting holes are in each side of the
drive and there are four mounting holes in the bottom of the
drive.

The maximum length that the screws should extend into the
chassis mounting holes is 0.15 inch (3.81 mm), measured
from the outer surface of the chassis. Tighten the screws
down e venly. Do not over -tighten or f orce the screw if it d oes
not seem to screw in easily, because this means the thre ads
are not properly aligned. In this case, back the screw out
and try again.

Installation des Laufwerkes
und Ansch lu ß der K abel

Beachten Sie bei m Han dhaben und Anfassen der Anschlußstifte
und Komponenten die Vorsichtsmaßnahmen zur Verhinderung
statischer Aufladung. Fassen Sie das Laufwerk nur am Rahmen
an.

Das Laufwerk kann in beliebiger Orientierung (horizontal, ver­tikal oder schräg) installiert werden; jedoch muß dafür gesorgt
werden, daß ein ausreichender Luftstrom zur Kühlung des Lauf­werkes vorhanden ist.

32 Cheetah 18 Installation Guid e, Rev. A

1. Befestigen Sie das Laufwerk mit vier 6-32-UNC-Schrauben

am Gehäuse des Host-Syst ems. Die beiden Seiten des
Laufwerkes sind mit jeweils zwei Befestigungslöchern
versehen, die Unterseite des Laufwerkes wei st vier weitere
Befestigungslöcher auf.

Gemessen von der Außenfläche des G ehäuses dürfen die
Schrauben maximal 3,81 mm in die Befestigungslöcher des
Gehüus es hinei nragen. D ie Schra uben mü ssen gl eich­mäßig, jedoch nicht zu fest, angezogen werden. Wenn sich
eine Schraube nicht ohne Widerstand einschrauben läßt,
sind die Gewinde nicht korrekt aneinander ausgerichtet. In
diesem Fall die Schrau be nich t in da s Gewi ndeloch
forcieren, sondern die Schraube herausnehmen und erneut
in das Gewindeloch einführen.

2. Verify that all connections between the drive and the host

system are correctly installed.

2. Prüfen Sie, ob alle Verbindungen zwischen dem Laufwerk

und dem Host-System korrekt hergestellt sind.

3. Verify that y ou have correctly installed jumpers.

3. Stellen Sie sicher, daß die Kennungsbrücken installiert sind.

4. Connect the SCSI cable into the drive’s SCSI connector.

Take care not to s tretch or crimp this cable, and do not b lock
the system’s cooling air flow with the cable.

The drive receives DC power through a 4-pin connector
mounted next to the SCSI connector. The output of a power
supply must meet SELV (safety extra low voltage) as

Cheetah 18 Installation Guid e, Rev. A 33

defined in IEC 950. Figure 8 provides the pin information for
the DC power connector. To connect the DC power cable to
the drive, simply insert the cable end into the drive’s DC
power connector.

4. Schließen Sie das SCSI- K abel an den SCSI-Steckverbinder

des Laufwer kes an. Da s Kabel darf nicht ge dehnt oder
gedrückt werden und es darf den Luftstrom zur Kühlung des
Systems nicht behindern.

Das Laufwerk wird über einen 4-poligen, neben dem SCSI­Anschluß befestigten Steckverbinder mit Gleichstrom ver­sorgt. Der Ausgang eines Netzteils muß SELV (safety extra
low voltage) nach IEC 950 entsprechen . Abbildung 8 zeig t
die Steckerbelegung für den Gleichstromanschluß. Zum
Anschlu ß des G leichs tromk abels an das L aufwer k das
Kabelende in den Gleichstromanschluß des Laufwerkes
stecken .

Pin

Pin

1
2
3
4

Power

+12V
+12V return
+ 5V return
+ 5V

Gleichstrom

1

+12 V

2

+12 V Rückleitung

3

+ 5 V Rückleitung

4

+ 5 V

4321

Figure 8. DC power connector
Abbildung 8. Gleichstromanschluß

34 Cheetah 18 Installation Guid e, Rev. A
Note. Signal ground on the power control board assembly

(PCBA) and the head and disc assembly (HDA) are con­nected together in this drive and you cannot separate
them. The equipment in which you have mounted the
drive is connected directly to the HDA and PCBA without
electrically isolating shock mounts. Maximizing the con­ductive contact area between HDA ground and system
ground may reduce radiated emissions.

If you do not want the system chassis to be connected to
the HDA/PCB ground, you must provide a nonconductive
(electricall y isolating) meth od of mounting the drive in the
host system. This may increase radiated emissions and
is the system designer’s responsibility.

Hinweis.

Die Signalerde auf der Stromregelungskarte (PCBA) und
der Kopf- und Festp latt enein heit (HDA) si nd in di esem
Laufwerk miteinander verbunden und können nicht
getrennt werden. Das Gerät, in das Sie das Laufwerk
eingebaut haben, ist ohne elektrisch isolierende
Stoßdämpfer direkt an di e HDA und PCB angeschlossen.
Die elektromagnetische Strahlung kann reduziert wer­den, indem Sie eine möglichst große leitende Kontak­fläche zwischen der HDA-Erdung und der Systemerdung
vorsehen.

Wenn Sie das Systemgehäuse nicht an die HDA /PCBA­Erdung anschließen wollen, müssen Sie das Laufwerk
auf nichtleitende Weise (galvanisch isoliert) im Host-Sys­tem einba uen. Die da raus u.U. resultie ren de vers tärkt e

Cheetah 18 Installation Guid e, Rev. A 35

elektromagnetische Strahlung fällt in den Zuständigkeits­bereich des Syste md esigners.

5. Replace the host system’s cover.

5. Setzen Sie das Gehäuseober teil des Host-Systems wieder

auf.

36 Cheetah 18 Installation Guid e, Rev. A

K

-Z-

J

Notes:

Mounting holes are 6-32 UNC 2B, three

[1]

on each side and four on the bottom.
Max screw penetration into side of drive
is 0.15 in. (3.81 mm). Max screw
tightening torque is 6.0 in-lb (3.32 nm)
with minimum full thread engagement of

0.12 in. (3.05 mm).

Dimension Table

Inches

A

1.654

max

B

5.787

max

C

4.000

± .010

D

3.750

± .010

E

.125

± .010

F

1.750

± .010

G

1.625

± .020

H

1.122

± .020

J

4.000

± .010

K

.250

± .010

L

1.638

± .010

M

.181

± .020

P

1.625

± .020

R

.265

± .010

S

.315

± .040

T

.015

max

U

.015

max

Millimeters

42.01

max

147.00

max

101.60

± .25

92.25

± .25

3.18

± .25

44.45

± .25

41.28

± .50

28.50

± .50

101.60

± .25

6.35

± .25

41.60

± .25

4.60

± .50

41.28

6.73

7.00

0.38

0.38

± .50
± .25
± .10

max
max

U

-Z-T//

-Z-

-X-

S

A

M

P

[1]

G

F

HL

[1]

B

DE

C

-X-

R

Figure 9. Mounting configuration dimensions (LW model)

Cheetah 18 Installation Guid e, Rev. A 37

K

-Z-

J

Notes:

Mounting holes are 6-32 UNC 2B, three

[1]

on each side and four on the bottom.
Max screw penetration into side of drive
is 0.15 in. (3.81 mm). Max screw
tightening torque is 6.0 in-lb (3.32 nm)
with minimum full thread engagement
of 0.12 in. (3.05 mm).

Dimension Table

Inches

A

1.654

max

B

5.787

max

C

4.000

± .010

D

3.750

± .010

E

.125

± .010

F

1.750

± .010

G

1.625

± .020

H

1.122

± .020

J

4.000

± .010

K

.250

± .010

L

1.638

± .010

M

.181

± .020

N

.040

max

P

1.625

± .020

R

2.618

± .010

S

.276

± .040

T

.015

max

U

.015

max

Millimeters

42.01

147.00

101.60

92.25

3.18

44.45

41.28

28.50

101.60

6.35

41.61

4.60

1.20

41.28

66.50

7.00

0.38

0.38

max
max

± .25

± .25

± .25

± .25
± .50
± .50
± .25
± .25
± .25
± .50

max

± .50
± .25
± 1.02

max
max

U

-Z-T//

-Z-

-X-

P

S

A

M

[1]

G

F

HL

[1]

B

R

-Z- -X-N

DE

C

-X-

Figure 10. Mounting configuration dimensions (LC model)

38 Cheetah 18 Installation Guid e, Rev. A

Formatting the drive

Warning.

Note.

1. Turn on DC power.

2. Boot the system from a system floppy di sc or from a previ-

3. Format the disc drive. Cheetah 18 disc drives are designed

Quick reference desktop system notes

• Hardware platform, operat ing system, and host adapter var ia-

tions can limit access to the full capacity of this and other high

capacity drives. Refer to your system or utility manual for

detailed in structions.

• DOS/Windows 3.1 /W indows 95. Set the drive type in CMOS to

“

Zero,” “N one,”

and FORMAT.EXE.

• Macintosh. Use a third-party drive utility or Apple’ s Drive Setup

(version 1.3.1 or later) to initialize the drive. Note: versions of

Apple Drive Setup prior to version 1.3.1 do not recognize non-

Apple drives .

Formatting a drive erases all user data. Be sure that
you understand this principle before formatting any
hard disc drive. It is not necessary to format a drive
that previously has been used to store data, unless
your intention is to erase all user data.

Seagate is not responsible for lost user data.

ously installed hard disc drive if there is one.

to operate with a variety of operating systems. Please refer
to your system or SCSI controller manual for information
about formatting and setting up the drive. Some quick desk­top system notes are provided below.

or “

No hard drive installed

.” Use FDISK.EXE

Cheetah 18 Installation Guide, Rev. A 39

LW drives

LW drives sectionSetting the SCSI ID ju mpers

Use the J6 connector to set the SCSI ID (see Figure 11). To
change the SCSI ID, install jumpers as shown in the illu str ation.

Drive
Front

Jumper Plug

(enlarged to
show detail)

Pin 1

J6

SCSI ID = 0
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

Figure 11. Setting the SCSI ID on ST118202LW drives

40 Cheetah 18 Installation Guid e, Rev. A

LW drives

Te rminating th e drive

ST118202LW drives do not have internal terminators or any
other way of adding internal termination to t he drive. You must
provide ex ternal termination to these drives when ter mination is
required. This is normally done by adding an in-l ine t erminator
on the cable.

Note.

Use active (ANSI SCSI-2 Alternative 2) single-ended ter­minators when terminating a bus operating in single­ended mode. Use SPI-2-compliant active low voltage dif­ferential terminators when terminating a SCSI Ultra2 bus
operating in LVD mode.

Cheetah 18 Installation Guide, Rev. A 41

LW drives

T erminator po wer

You can configure this drive to supply termination power to the
SCSI bus by placing a jumper on J2 pins 1 and 2. The default
setting is no jumper, meaning that some other source (other than
this drive) i s suppl ing termination power to the SCSI bus.

J2

Term. Power to SCSI Bus
Host adapter or other device provides

term power to external terminator

TEDSMEWPP

Pin 1
Pin 2

R

R

E

EST

D

S

P

J2

J2 Jumper Plug

(enlarged to
show detail)

J6

Drive
Front

Figure 12. Setting terminator power jumpers

42 Cheetah 18 Installation Guid e, Rev. A

LW drives

Other appli cabl e jump e r op tions

Sev eral other jumpe r options are available as illustrated.

J2

Reserved
Single-Ended Mode option

Use single-ended or low voltage differential mode.
Force the drive to operate only in single-ended mode.

Delay Motor Start option
(valid only if the Enable Motor Start jumper is not connected)

Disable the Delay Motor Start option (default).
Motor start delay equal to the SCSI ID multiplied by 12 seconds.

For example, if the SCSI ID = 2, the drive starts in 24 seconds.
Motor Start option

Disable motor start (default). The drive starts according to the
Delay Motor Start option.

Enable motor start. The drive waits for the Start Unit command
from the host before starting the spindle motor.

Write Protect option
Write protect = Off (enables writing – default).
Write protect = On (disables writing).

Parity Check option
Enable parity check of SCSI bus (default).
Disable parity check.

SEDSMEWPP

Pin 1
Pin 2

R

R

E

EST

D

S

P

J2 Jumper Plug

(enlarged to
show detail)

J6

Drive
Front

J2

Cheetah 18 Installation Guide, Rev. A 43

LW drives

68 Pin

SCSI I/O Connector

J1

SCSI Address A0
SCSI Address A1
SCSI Address A2
SCSI Address A3
No connection
+5V
Fault LED*
Vendor Unique*
Reserved
Activity LED*
Ground

These pins are driven low for

*

250 ms after PWR ON or
RESET to allow jumper
selectable SCSI ID as shown
to the right.

Pin 1

Pin 12

J5/J1A [2][4]

J1A Pin 1

Pin 1

1P2P3P4P

J1-DC Power

SCSI ID = 0
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

Figure 13. Additional jumper options
Figure 14. Alternate ID select and LED connection

44 Cheetah 18 Installation Guid e, Rev. A

LW drives

Drive Active indicator

The drive Active LED indicator connections are shown below.

Drive
Front

Jumper Plug
(enlarged to
show detail)

Pin 1

CATH

Reserved
Activity LED

Reserved
The shaded pins are shipped
with a cover installed. Do not
install jumpers on these pins.
Retain the cover unless you
install a 20-pin plug.

Note: On some LEDs the flat
side of indicator is cathode.

J6

Figure 15. Drive Active LED indicator connections

Cheetah 18 Installation Guide, Rev. A 45

LC drives

LC drives sectionSetting the SCSI ID ju mpers

The SCSI ID for ST118202LC drives is normally set over the
SCSI bus by the host system. You can also use the J6 jumper
block to set the SCSI ID (see Figure 16).

Drive

Front

Jumper Plug

(enlarged to
show detail)

Pin 1

J6

SCSI ID = 0 (default)
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

Figure 16. Setting the SCSI ID on ST118202LC drives

Note:

[1] Do not remove
cover from pins
13 through 20
(darkened area).

46 Cheetah 18 Installation Guid e, Rev. A

LC drives

Te rminating th e drive

LC model drives do not have internal terminators or any ot her
way of adding internal termination to the drive. You must provide
external termination to these drives when termination is
required. Since this drive is designed to be plugged into a back­panel or other host enclosure without cabling, this is normally
done by enab li ng termination on the backpanel or plane.

Note.

Use active (ANSI SCSI-2 Alternative 2) single-ended ter­minators when terminating a bus operating in single­ended mode. Use SPI-2-compliant active low voltage dif­ferential terminators when terminating a SCSI Ultra2 bus
operating in LVD mode.

T erminator po wer

ST118202LC drives cannot be configured to provide termination
power.

Cheetah 18 Installation Guide, Rev. A 47

LC drives

Other a ppl i ca bl e jum p e r op tions

Other option ju mpers are available as illustrated below.

J2

Reserved
Single-Ended Mode option

Use single-ended or low voltage differential mode.
Force the drive to operate only in single-ended mode.

Delay Motor Start option
(valid only if the Enable Motor Start jumper is not connected)

Disable the Delay Motor Start option (default).
Motor start delay equal to the SCSI ID multiplied by 12 seconds.

For example, if the SCSI ID = 2, the drive starts in 24 seconds.
Motor Start option

Disable motor start (default). The drive starts according to the
Delay Motor Start option.

Enable motor start. The drive waits for the Start Unit command
from the host before starting the spindle motor.

Write Protect option
Write protect = Off (enables writing – default).
Write protect = On (disables writing).

Parity Check option
Enable parity check of SCSI bus (default).
Disable parity check.

SEDSMEWPP

Pin 1
Pin 2

R

R

R

E

E

E

D

S

S

S

J6

Drive

J2 Jumper Plug

(enlarged to
show detail)

Front

Figure 17. Additional jumper options

J2

48 Cheetah 18 Installation Guid e, Rev. A

LC drives

WC/DC drives sectionDrive Active indicator

The drive Active LED indicator connections are shown below.

Drive
Front

Jumper Plug

(enlarged to
show detail)

Pin 1

CATH

Reserved
Activity LED

Reserved
The shaded pins are shipped
with a cover installed. Do not
install jumpers on these pins.
Retain the cover unless you
install a 20-pin plug.

Note: On some LEDs the flat
side of indicator is cathode.

J6

Figure 18. Drive Active LED indicator connections

Seagate Tech no logy, Inc.
920 Disc Drive, Scotts Val ley, CA 95066-4544, USA

Publicat ion Number: 83329250, Rev. A, Printed in USA