Table of Contents
Advertisement
About SCSI Components
About SCSI Bus
LVD SCSI
Wide SCSI
SCSI ID
SCSI Bus Termination
The SCSI system is composed of the following components.
• Initiator
This is a host computer system that functions as an initiator program of
commands. The system consists of the application software, the operating
system, the device driver and the SCSI adapter card.
• Bus
By connecting the SCSI cables to the SCSI adapter card, the library and other
devices, a path (or a bus) is created for transferring commands.
• Targets
The AIT library and the AIT drive are peripheral devices (or targets) that
receive commands from the host computer. Up to 16 devices (including the
host computer) can be connected to the Wide SCSI bus. Also, up to 8 devices
can be connected to the Narrow SCSI bus.
When you are setting up the AIT library using a SCSI bus, please note the
following precautions
The AIT library is an LVD SCSI device. All SCSI devices connected to the AIT
library on the SCSI bus must be LVD SCSI devices.
The interface of the AIT library is Wide SCSI. In order to connect the AIT
library to a Narrow SCSI bus, use a 50-pin to 68-pin LVD SCSI adapter. Also,
make sure every unused data lines are terminated by an adapter.
Set a unique SCSI ID for each device on a SCSI bus. The host computer uses
these SCSI IDs to differentiate between the devices. Also, the SCSI IDs are used
to prioritize the order of communication when several devices are
communicating with the host computer. The lower the ID number, the lower the
priority it has.
Caution
The SCSI ID of a device has nothing to do with its physical location. For
example, in a SCSI bus that has multiple devices connected to it, the SCSI ID
of the last device can be 2.
If the AIT library is the device connected to the end edge of the SCSI bus, you
must attach a terminator to the unused SCSI connector to terminate the SCSI
bus. Now, the AIT library can supply electric power to the terminator. For
information about details, refer to"Setting the DIP Switches" (page 19) in
Chapter 2, "Installation".
87
Appendix
Advertisement
Table of Contents
