Computer Busses

7

SCSI

7.1 Introduction

SCSI has many advantages over IDE, these include:

• A single bus system for up to seven connected devices.

• It supports many different peripherals, such as hard disks, tape drives, CD-ROMs, and so on.

• It supports device priority where a higher SCSI-ID has priority over a lower SCSI-ID.

• It supports both high-quality connectors and cables, and low-quality connection and ribbon cable.

• It supports differential signals, which gives longer cable lengths.

• Extended support for commands and messaging.

• Devices do not need individual IRQ lines (as they do in IDE) as the controller communicates with the devices.

• It has great potential for faster transfer and enhanced peripheral support.

7.2 SCSI types

SCSI has an intelligent bus subsystem ...