Bull 32X SCSI-2 CD-ROM Drive, Installation And Using Manual

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Note: If you are installing the auto-docking version of this device on your system, the
remainder of this chapter does not apply to your system. See your system
documentation for information about the auto-docking feature.
Planning Your SCSI Device Layout
SCSI devices include such hardware as disk drives, tape drives, CD-ROM drives,
scanners, and printers. Some SCSI devices can be connected to or installed inside your
system unit, while others can be installed externally. The devices are attached, in a
daisy-chain configuration, to a SCSI adapter installed inside the system unit.
Each device in the chain has a unique SCSI address (also called a SCSI ID). When
you connect more than one SCSI device, it is important that you plan the location and
address of each device in the chain. You must also be sure to connect a terminator at
each end of the chain. If you are using an internally connected device the SCSI adapter
provides the termination for that end. The last attached device must terminate the other
end of the chain.
If your configuration includes both internal and external devices, you must connect a
terminator to the last external device and terminate the internal SCSI cable. The
adapter terminates one end of the chain and the last device terminates the other end.
Determining Your SCSI Device Address
Before you install the 32X SCSI-2 CD-ROM Drive, you must set the SCSI address on
the drive. First, you must determine which SCSI addresses are available to use. Then
you choose an address and install jumpers on the drive to set the selected address.
You can use any available SCSI address as long as no two SCSI devices on the same
chain use the same address. No device can use address 7, which is reserved for the
SCSI adapter.
SCSI addresses are in sequential order from highest to lowest priority. Refer to Table 1
below for the priority associated with each SCSI address. For the best performance,
choose the highest unused SCSI address between 6 and 0.
Note: Use only SCSI addresses 6 through 0 for this device.
Table 1. Data Access Priorities for SCSI Addresses
Priority SCSI Address SCSI Device Name
Highest Priority 7 Adapter
↓
6
↓
5
↓
4
↓
3
↓
2
↓
1
4
32X SCSI-2 CD-ROM Drive Installation and Using Guide