PCA-6185 User’s Manual 68
Chapter 7 SCSI Setup
7.1 Introduction
The PCA-6185 is equipped with an Adaptec AIC-7902 single-chip PCI-
to-SCSI host adapter which provides a dual channel Ultra 320 multitask-
ing interface between your computer’s PCI bus and SCSI devices (disk
drives, CD-ROM drives, scanners, tape backups, removable media
drives, etc.). Ultra 320 is a new generation of SCSI technology that
expands SCSI performance from 80 MBytes/sec to 320 MBytes/sec. Up
to a total of 15 SCSI devices can be connected to each of the SCSI con-
nectors.
The AIC-7902 combines this Ultra 320 SCSI technology with Adaptec’s
SpeedFlex™ technology. SpeedFlex allows the Adaptec SCSI card to be
backwards compatible with previous generations of SCSI products, while
allowing newer Ultra 320 SCSI devices to operate at the higher 320
MBytes/sec rate.
If you need to configure the SCSI, the onboard SCSI Select configuration
utility allows you to change host adapter settings without opening the
computer or handling the board. The SCSI Select utility also contains a
utility to low-level format and verifies the disk media on your hard disk
drives.
Note: If any peripheral is running at SE mode, the Ultra 320
SCSI segment will run at speeds up to 40 MBytes/
sec only instead of 320 MBytes/sec.
7.2 Understanding SCSI
SCSI (pronounced “scuzzy”) stands for Small Computer Systems Inter-
face. SCSI is an industry standard computer interface for connecting
SCSI devices to a common SCSI bus.
A SCSI bus is an electrical pathway that consists of a SCSI interface
installed in a computer and one or more SCSI devices. SCSI cables are
used to connect the devices to the SCSI interface. For the SCSI bus to
function properly, a unique SCSI ID must be assigned to the SCSI inter-
face and each SCSI device connected to it, and the SCSI bus must be
properly terminated.
