Table Of Contents - Adaptec AHA-1740A Technical Reference Manual

Table of Contents

Preface ............................................................................................................................... xi
Conventions...................................................................................................................... xii
Chapter One - Introduction
Document Scope.............................................................................................................. 1-1
Purpose............................................................................................................................ 1-1
AHA-1740A/1742A/1744 Product Features................................................................... 1-2
EISA Features .......................................................................................................... 1-2
SCSI Features .......................................................................................................... 1-2
Board Features......................................................................................................... 1-3
Configuration Diskette and Installation Guide (ASW-C174)....................................... 1-4
Product Specifications .................................................................................................... 1-5
Extended Industry-Standard Architecture Interface ................................................... 1-5
Standard EISA Bus Electronic and Physical Interface ......................................... 1-5
SCSI Interface................................................................................................................. 1-6
Electrical Interface for AHA-1740A/1742A ............................................................ 1-6
Electrical Interface for AHA-1744........................................................................... 1-7
Internal Connector ................................................................................................... 1-7
External Connector .................................................................................................. 1-8
Floppy Disk Interface ..................................................................................................... 1-9
Standard Electronic and Physical interface ........................................................... 1-9
Connector.................................................................................................................. 1-9
Radiation Immunity ....................................................................................................... 1-9
Reference Documents ..................................................................................................... 1-9
Chapter Two - Architecture
Hardware ........................................................................................................................ 2-1
Bus Master DMA...................................................................................................... 2-2
SCSI Interface and Protocol Chip (AIC-6251) ........................................................ 2-2
8- and 16-Bit Memory and Odd Byte Data Transfers ............................................ 2-3
Bus Auxiliary Interface Chip (AIC-565) ................................................................. 2-3
EISA Configuration Chip (AIC-575) ....................................................................... 2-4
BMIC Bus Interface Chip (82355)........................................................................... 2-4
Floppy Disk Controller (AHA-1742A Only) ............................................................ 2-4
Standard Mode Firmware .............................................................................................. 2-5
Mailboxes .................................................................................................................. 2-5
Command Control Block.......................................................................................... 2-6
Command Descriptor Block .................................................................................... 2-7
Principles of Operation ............................................................................................ 2-8
Task Queuing ........................................................................................................... 2-8
Enhanced Mode Firmware ............................................................................................. 2-9
Onboard BIOS Operation ............................................................................................. 2-11
Power-Up Diagnostics .................................................................................................. 2-11
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