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Appendix
About SCSI Components
The SCSI system is composed of the following components.
• Initiator
This is the host computer system used to transfer commands. The system
consists of the application software, the operating system, the device driver,
the SCSI adapter card, etc.
• 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.
About SCSI Bus
When you are setting up the AIT library using a SCSI bus, please note the
following precautions
LVD SCSI
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.
Wide SCSI
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.
SCSI ID
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.
Caution
The SCSI ID of a device has nothing to do with its physical location.
SCSI Bus Termination
If the AIT library is the device connected to the end of the SCSI bus, you must
attach a terminator to the unused SCSI connector to terminate the SCSI bus. The
AIT library can supply electric power to the terminator. For information about
details, refer to“Setting the DIP Switches” (page 18) in Chapter 2,
“Installation”.
