Adaptec AHA-2740W User manual

AHA-2740W/2742W/2744W
Stock Number: 510647-00, Rev. A Page: Front Cover
Print Spec Number: 492897-00
Current Date: 8/3/94 ECN Date: 8/9/94
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User’s GuideUser’s Guide
AHA-2740W/2742W/2744W
EISA-to-Fast, Wide SCSI Host Adapters
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AHA-2740W/2742W/2744W
Stock Number: 510647-00, Rev. A Page: Back Cover
Print Spec Number: 492897-00
Current Date: 8/3/94 ECN Date: 8/9/94
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Adaptec, Inc.
691 South Milpitas Boulevard
Milpitas, CA 95035
Copyright © 1993, 1994, Adaptec, Inc.
All rights reserved. Adaptec and the
Adaptec logo are registered trademarks
of Adaptec, Inc.
Printed in Singapore
STOCK NO.: 510647-00, Rev. A LL 08/94

AHA-2740W/2742W/2744W User’s Guide
Stock Number: 510647-00, Rev. A Page: i
Print Spec Number: 492897-00
Current Date: 8/3/94 ECN Date: 8/9/94
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▼ ▼ ▼ ▼ AHA-2740W/2742W/2744W
EISA-to-Fast, Wide SCSI Host Adapters
User’s Guide

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AHA-2740W/2742W/2744W User’s Guide
Stock Number: 510647-00, Rev. A Page: ii
Print Spec Number: 492897-00
Current Date: 8/3/94 ECN Date: 8/9/94
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Copyright
Copyright © 1993, 1994 Adaptec, Inc. All rights reserved. No part of this publication
may be reproduced, stored in a retrieval system, or transmitted in any form or by any
means, electronic, mechanical, photocopying, recording or otherwise, without the
prior written consent of Adaptec, Inc., 691 South Milpitas Blvd., Milpitas, CA 95035.
Trademarks
Adaptec, the Adaptec logo, AHA, and PhaseEngine are registered trademarks and
EZ-SCSI is a trademark of Adaptec, Inc.
Bernoulli is a registered trademark of Iomega Corporation.
AT&T is a registered trademark of American Telephone and Telegraph Company
IBM, AT, and Micro Channel are registered trademarks of International Business
Machines Corporation.
MS-DOS is a registered trademark of Microsoft Corporation.
NetWare is a registered trademark of Novell, Inc.
SCO is a registered trademark of the Santa Cruz Operation, Inc.
UNIX is a registered trademark of Unix System Laboratories.
All other product names are trademarks or registered trademarks of their respective
owners.
Changes
The material in this document is for information only and is subject to change with-
out notice. While reasonable efforts have been made in the preparation of this docu-
ment to assure its accuracy, Adaptec, Inc. assumes no liability resulting from errors or
omissions in this document, or from the use of the information contained herein.
Adaptecreserves the right to make changes in the product design without reservation
and without notification to its users.
Adaptec Technical Support
Adaptec products have been specifically developed for easy installation and use. We
believe that our documents and the onscreen instructions and help are complete and
clear enough to meet your needs. If you need more assistance, please contact us.
●The Adaptec Electronic Bulletin Board Service (BBS) provides information on soft-
ware upgrades, new releases, technical advice, and other topics. The BBS is avail-
able 24 hours a day at 408-945-7727; 1200/2400/9600/14400 baud, 8 data bits,
1 stop bit, no parity.
●To contact the Adaptec Technical Support Hot Line, call 800-959-SCSI (7274) or
408-945-2550; M–F: 6:00 a.m. to 5:00 p.m., Pacific Time.
Interactive FAX Service
The Adaptec Interactive FAX Service provides the latest online information about
Adaptec products and services. The Adaptec Interactive FAX Service is available
23 hours a day, 7 days a week, at 408-957-7150.

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AHA-2740W/2742W/2744W User’s Guide
Stock Number: 510647-00, Rev. A Page: iii
Print Spec Number: 492897-00
Current Date: 8/3/94 ECN Date: 8/9/94
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Ordering Software and Cables
To order Adaptec software and SCSI cables, call 800-442-SCSI (7274), M–F: 6:00 a.m. to
5:00 p.m., Pacific Time. If you are calling from outside the U.S. and Canada, the num-
ber is 408-957-SCSI (7274).
Literature Hotline
To request additional documentation for Adaptec products, call 800-934-2766,
M–F: 5:00 a.m. to 6:00 p.m., Pacific Time.
FCC Compliance Statement
This equipment has been tested and found to comply with the limits for a Class B digital device,
pursuant to Part 15 of the FCC rules. These limits are designed to provide reasonable protection
against harmful interference in residential installations. This equipment generates, uses, and can
radiate radio frequency energy, and if not installed and used in accordance with the instructions,
may cause harmful interference to radio communications. However, there is no guarantee that
interference will not occur in a particular installation.
If this equipment does cause interference to radio or television equipment reception, which can be
determined by turning the equipment off and on, the user is encouraged to try to correct the inter-
ference by one or more of the following measures:
• Reorient or relocate the receiving antenna
• Move the equipment away from the receiver
• Plug the equipment into an outlet on a circuit different from that to which the receiver is
powered
• If necessary, the user should consult the dealer or an experienced radio/television technician
for additional suggestions
CAUTION: Only equipment certified to comply with Class B (computer input/output devices,
terminals, printers, etc.) should be attached to this equipment, and must have shielded interface
cables.
Finally, any changes or modifications to the equipment by the user not expressly approved by the
grantee or manufacturer could void the user’s authority to operate such equipment.
Each host adapter is equipped with an FCC compliance label which shows only the FCC identifi-
cation number. The full text of the associated label follows:
This device complies with part 15 of the FCC rules. Operation is subject to the following
two conditions: (1) this device may not cause harmful interference and (2) this device
must accept any interference received, including interference that may cause undesired
operation.

AHA-2740W/2742W/2744W User’s Guide
Stock Number: 510647-00, Rev. A Page: iv
Print Spec Number: 492897-00
Current Date: 8/3/94 ECN Date: 8/9/94
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AHA-2740W/2742W/2744W User’s Guide
Stock Number: 510647-00, Rev. A Page: v
Print Spec Number: 492897-00
Current Date: 8/3/94 ECN Date: 8/9/94
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v
Table of Contents
Preface
Inside This Document xi
Conventions xii
Advisories xiii
1 Introduction
About This Chapter 1-1
Overview 1-3
The AHA-2740W/2742W/2744W Host Adapters 1-3
Features 1-4
Fast Data Transfer Rates 1-4
Maximum Off-loading the Host CPU 1-4
Fully Disk Array Capable 1-4
Advanced Fast SCSI-2/SCSI-3 Implementation 1-4
Multiple Device and Applications Support 1-5
Configuration Flexibility 1-5
Board Layout 1-6
Default Settings 1-8
The Onboard Floppy Controller (AHA-2742W and
AHA-2744W Only) 1-8
Unpacking and Inspection 1-9
2 Getting Started
About This Chapter 2-1
Installation Overview 2-3
The Host Adapter and the SCSI Bus 2-4
Quick Installation 2-5
Prepare Your SCSI Devices 2-5
Install Your Host Adapter and Peripherals 2-6
Configure the Host Adapter 2-7
Installation 2-8
Termination on the SCSI Bus 2-9

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AHA-2740W/2742W/2744W User’s Guide
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68-pin Internal Connector Only 2-12
68-pin External Connector Only 2-12
68-pin Internal and 68-pin External
Connectors 2-13
50-pin Internal Connector Only 2-13
50-pin and 68-pin Internal Connectors 2-14
50-pin Internal and 68-pin External
Connectors 2-14
50-pin and 68-pin Internal Connectors, and
68-pin External Connector 2-15
SCSI ID Setting 2-15
Installing the Host Adapter 2-16
Cabling the Host Adapter 2-17
Connecting Standard 8-bit Internal SCSI
Devices 2-17
Connecting 16-bit Internal Wide SCSI
Devices 2-20
Connecting 16-bit External Wide SCSI
Devices 2-22
Connecting Floppy Drives (AHA-2742W and
AHA-2744W Only) 2-25
SCSI Bus Activity LED Connector 2-27
Before Rebooting Your System 2-28
Reassemble the System 2-28
3 Configuring the Host Adapter
About This Chapter 3-1
The EISA Configuration Utility 3-3
Run the EISA Configuration Utility 3-3
Copy Configuration and Overlay Files 3-4
Select the Host Adapter 3-4
Configure the Host Adapter Parameters 3-5
Interrupt Level 3-5
Bus Release Time 3-6
Data FIFO Threshold 3-6
Host Adapter BIOS Base Address 3-7
Wide SCSI Channel Interface Definitions 3-8

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Table of Contents
AHA-2740W/2742W/2744W User’s Guide
Stock Number: 510647-00, Rev. A Page: vii
Print Spec Number: 492897-00
Current Date: 8/3/94 ECN Date: 8/9/94
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Host Adapter SCSI ID 3-8
SCSI Bus Parity Check 3-9
SCSI Selection Timeout 3-10
SCSI Bus Reset at Power-on 3-10
SCSI Bus Termination (AHA-2740W and
AHA-2742W Only) 3-11
BIOS and Device Configuration 3-11
BIOS Configuration 3-12
Device Configuration 3-13
Exit SCSI Device Configuration 3-18
Exit the EISA Configuration Utility 3-18
Utilities 3-18
Disk Format Utility 3-19
Disk Format 3-19
Disk Verify 3-19
4 Troubleshooting
About This Chapter 4-1
SCSI Troubleshooting Checklist 4-3
Problems and Solutions 4-4
Conflicts With Other Options 4-6
A Specifications
About This Appendix A-1
Technical Information A-3
Product Specifications A-3
Physical Dimensions A-3
Power Requirements A-3
Environmental Requirements A-3
Extended Industry-Standard Architecture
Interface A-4
SCSI Interface A-4
Electrical Interface A-4
Single-ended Output Signals A-4
Single-ended Input Signals A-5
Differential Output Signals A-5
Differential Input Signals A-5

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AHA-2740W/2742W/2744W User’s Guide
Stock Number: 510647-00, Rev. A Page: viii
Print Spec Number: 492897-00
Current Date: 8/3/94 ECN Date: 8/9/94
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50-pin SCSI Connector A-6
68-pin SCSI Connectors A-6
Floppy Disk Interface A-11
Standard Electronic and Physical Interface A-11
Connector A-11
B I/O Operating Environment
About This Appendix B-1
Host Adapter Support B-3
DOS/Windows B-3
Adaptec EZ-SCSI B-4
C Optimizing Performance
About This Appendix C-1
Performance Tips C-3
Enabling Synchronous Negotiation C-3
Enabling Wide Negotiation C-3
Disabling the Host Adapter BIOS C-4
Enabling SCSI Bus Parity C-4
Setting Enable Disconnection C-4
Send Start Unit Command C-4
DOS/Windows Performance C-5
D Disk Drives Over 1 GByte
About This Appendix D-1
Extended Translation (Using DOS 5.0) D-3
The DOS 1 GByte Limit D-3
When to Use Extended Translation D-3
With DOS V 5.0 Only D-3
Drives With Mixed Partitions D-4
Using Fdisk D-4
Questions and Answers About Extended
Translation D-4
Glossary
Index

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Figure
List of Figures
1-1 Board Layout for the AHA-2740W and
AHA-2742W 1-6
1-2 Board Layout for the AHA-2744W 1-7
2-1 Connectors on the Host Adapter 2-8
2-2 Location of Resistor Networks on the
AHA-2744W 2-10
2-3 Pin-1 Orientation on Resistor Networks 2-11
2-4 Internal Wide SCSI Devices Only 2-12
2-5 External Wide SCSI Devices Only 2-12
2-6 Internal and External Wide SCSI Devices 2-13
2-7 Internal 8-bit SCSI Devices Only 2-13
2-8 Internal 8-bit and Internal Wide SCSI Devices 2-14
2-9 Internal 8-bit and External Wide SCSI Devices 2-14
2-10 50-pin SCSI Ribbon Cable to Host Adapter 2-19
2-11 50-pin SCSI Ribbon Cable to Internal SCSI
Device 2-19
2-12 Connecting a Second Internal SCSI Device 2-20
2-13 68-pin Internal Cable to Host Adapter 2-21
2-14 68-pin Internal Cable to Internal Wide SCSI
Device 2-22
2-15 Connecting a Second Internal Wide SCSI Device 2-22
2-16 68-pin External Cable to Host Adapter 2-23
2-17 68-pin External Cable to Wide SCSI Device 2-24
2-18 Connecting Multiple External Wide SCSI
Devices 2-24
2-19 34-pin Floppy Cable to Host Adapter 2-25
2-20 34-pin Floppy Cable to First Floppy Drive 2-26

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AHA-2740W/2742W/2744W User’s Guide
Stock Number: 510647-00, Rev. A Page: x
Print Spec Number: 492897-00
Current Date: 8/3/94 ECN Date: 8/9/94
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Figure
2-21 Connecting a Second Floppy Drive 2-26
2-22 SCSI LED Connector 2-27
3-1 Host Adapter Parameters 3-4
3-2 Interrupt Level Selection 3-5
3-3 Bus Release Time Selection 3-6
3-4 Data FIFO Threshold Selection 3-6
3-5 Host Adapter BIOS Base Address Selection 3-7
3-6 Wide SCSI Channel Interface Definitions 3-8
3-7 Host Adapter SCSI ID Selection 3-9
3-8 SCSI Bus Parity Check Selection 3-9
3-9 SCSI Selection Timeout Selection 3-10
3-10 SCSI Bus Reset at Power-on Selection 3-10
3-11 SCSI Bus Termination Selection 3-11
3-12 BIOS and Device Configuration 3-11
3-13 BIOS Configuration Selection 3-12
3-14 SCSI Device Configuration 3-14
3-15 Exiting SCSI Device Configuration 3-18
3-16 Utility Selection 3-18

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Preface
Inside This Document
This document provides complete instructions on how
to install and use the Adaptec AHA-2740W/2742W/
2744W EISA-to-Fast, Wide SCSI Host Adapters.
Chapter 1 Introduction
provides general information about the
AHA-2740W/2742W/2744W host adapters. The fea-
tures, board layout, and default settings are included.
Chapter 2 Getting Started
has the information needed to install the host adapter
and SCSI devices.
Chapter 3 Configuring the Host Adapter
describes the EISA configuration utility and how it is
used to configure your host adapter. The chapter also
describes the utilities available through the EISA
configuration utility.
Chapter 4 Troubleshooting
has information to assist you in troubleshooting
problems that may occur during installation and
configuration.
AppendixA Specifications
lists technical specifications of the host adapter and its
connectors, which may be of use to the advanced user
or technician.
AppendixB I/O Operating Environment
provides information on using your host adapter with
various operating systems, such as DOS/Windows. A
brief discussion on Adaptec's EZ-SCSII/O Operat-
ing Environment Software is also included.

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AppendixC Optimizing Performance
has various tips on maximizing the performance of
your host adapter.
AppendixD Disk Drives Over 1 GByte
describes Adaptec's extended translation feature
which allows you to bypass the DOS 1024 cylinder
limit, and supports disk drives up to 8 Gigabytes
(GBytes) in size.
Conventions
The following typographic conventions are used
throughout this document.
bold
Used for keystrokes (.. press the Enter key ..) and
screen selection fields (.. select Backup Device and ..).
Helvetica
Used for operator entry that must be typed exactly as
shown ( .. device=c:\adaptec\aspidos.sys ..) and for
screen messages (..Enter Password ..).
Helvetica Italics
Used as a place holder for text you must determine and
type in (
.. enter nn for number ..). Also used for program
and file names in body text (.. the
autoexec.bat file ..).
Italics
Used for emphasis (.. is only supported ..) and docu-
ment reference (.. refer to Chapter 1, Introduction ..).
Hexadecimal Numbers
Are followed by an ‘h’, e.g., 330h.
End Mark
The ❒symbol marks the end of the text for each
chapter.

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Advisories
Advisories are quick notes that stress an important point
or warn of a potential hazard to your system or your
data. This document uses three types of advisories:
Note: Text set off in this way presents remind-
ers, tips, or suggestions which may simplify
the assembly and use of the host adapter.
Caution: Failure to observe this type of advi-
sory could result in damage to your system,
devices, and/or data.
WARNING: Failure to observe this type of
advisory could result in personal injury.
Use caution when handling any electrical equipment.
Advisories in this document can only cover the proce-
dures contained here, and not all situations may have
been addressed. Adaptec does not claim to have
included every condition or situation that might
require a Caution or Warning. You must refer to the
documentation for your computer peripheral equip-
ment when you are installing equipment or changing
its configuration.
❒

AHA-2740W/2742W/2744W User’s Guide
Stock Number: 510647-00, Rev. A Page: xiv
Print Spec Number: 492897-00
Current Date: 8/3/94 ECN Date: 8/9/94
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AHA-2740W/2742W/2744W User’s Guide
Stock Number: 510647-00, Rev. A Page: 1-1
Print Spec Number: 492897-00
Current Date: 8/3/94 ECN Date: 8/9/94
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1-1
1Introduction
About This Chapter
Read this chapter to find out
■An overview of the AHA-2740W/2742W/
2744W EISA-to-Fast SCSI host adapters
■The features of the AHA-2740W/2742W/
2744W
■The layout of the host adapter and all its
major components
■The default settings of the host adapter and
how to disable or enable the onboard
floppy controller on the AHA-2742W and
AHA-2744W

AHA-2740W/2742W/2744W User’s Guide
Stock Number: 510647-00, Rev. A Page: 1-2
Print Spec Number: 492897-00
Current Date: 8/3/94 ECN Date: 8/9/94
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1
1-3
Introduction
AHA-2740W/2742W/2744W User’s Guide
Stock Number: 510647-00, Rev. A Page: 1-3
Print Spec Number: 492897-00
Current Date: 8/3/94 ECN Date: 8/9/94
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Overview
This document provides information on how to install and
configure the AHA-2740W, AHA-2742W, and AHA-2744W EISA-to-
Fast, Wide SCSI host adapters in an EISA computer system.
The AHA-2740W, AHA-2742W and AHA-2744W support 16-bit Wide
SCSI via a 68-pin cable. In addition, a 50-pin cable connector is pro-
vided to connect 8-bit SCSI devices. The AHA-2742W and
AHA-2744W contain an onboard floppy controller.
In this document, the AHA-2740W, AHA-2742W, and AHA-2744W
are referred to jointly as the AHA-2740W/2742W/2744W.
The AHA-2740W/2742W/2744W Host Adapters
The AHA-2740W/2742W/2744W provide a high performance con-
nection between the EISA (Extended Industry Standard Architec-
ture) bus and the Wide SCSI (Small Computer System Interface) bus.
The AHA-2740W/2742W/2744W is a bus master device that trans-
fers data into host memory at burst rates of 33 MBytes/sec. These
transfers are generally 32 bits wide, except when transferring data
into 8- or 16-bit memory.
Bus mastering minimizes host CPU overhead, since the
AHA-2740W/2742W/2744W has an onboard sequencer (SCSI
PhaseEngine™) that allows it to independently manage data trans-
fer between SCSI devices and the computer system memory, with-
out requiring the involvement of the CPU. This is the highest
performance type of data transfer available for the EISA bus in
multitasking operating systems.
The AHA-2740W and AHA-2742W support only single-ended SCSI
devices, while the AHA-2744W supports only differential SCSI
devices. Most of the SCSI drives on the market today are single-ended.
WARNING: Differential SCSI devices may be damaged if con-
nected to the single-ended SCSI host adapter bus; similarly,
single-ended SCSI devices may be damaged if connected to
differential host adapters.

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AHA-2740W/2742W/2744W User’s Guide
AHA-2740W/2742W/2744W User’s Guide
Stock Number: 510647-00, Rev. A Page: 1-4
Print Spec Number: 492897-00
Current Date: 8/3/94 ECN Date: 8/9/94
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Like all EISA I/O cards, the AHA-2740W/2742W/2744W does not
have jumpers to change various EISA configuration options. These
options are changed via the EISA configuration utility provided
with every EISA system; however, the AHA-2742W and
AHA-2744W do have a single jumper (J1) that is used to enable or
disable the onboard floppy controller.
Features
Fast Data Transfer Rates
■16-bit Wide SCSI data transfer
■Up to 33 MBytes/sec burst on EISA bus enabled by large
256-byte FIFO
■4.0 MBytes/sec asynchronous Wide SCSI data rate
■10.0 MBytes/sec synchronous Wide SCSI data rate
■20.0 MBytes/sec synchronous Fast/Wide SCSI data rate
Maximum Off-loading the Host CPU
■Onboard sequencer (SCSI PhaseEngine) automates all SCSI
protocol
■Low SCSI processing overhead
■Bus Master DMA implementation
■Task scheduling and message-based communication
■Programmable interrupts
■32-, 16-, and 8-bit host bus data transfer
Fully Disk Array Capable
■Able to boot from any drive on the SCSI bus
■Background processing permits smooth error recovery
■Extensive support from leading disk array vendors
Advanced Fast SCSI-2/SCSI-3 Implementation
■Concurrent support of both 8-bit SCSI-2 and 16-bit SCSI-3 devices