IBM 4mm DDS-2 Tape Autoloader, Installation And User Manual

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Planning your SCSI Device Layout
SCSI devices are attached to a SCSI adapter in a chain. Devices in the chain can
be internal (inside your system unit) or external (connected outside your system unit).
If you are connecting more than one SCSI device, it is important that you plan the
layout of your SCSI chain.
Note: At each end of the SCSI chain, a terminator is required.
Planning SCSI Addresses
Make sure no two SCSI devices have the same address, and that no device uses
the SCSI address 7, which is used by the SCSI adapter. If the system and adapter
supports the Wide (16 data bit, 68 conductor cable) SCSI interface, you may see
addresses in the range of 0 through 15.
Note: For addresses in the range of 0 through 7, priority is assigned in descending
address order. Refer to Table 2-1 for the priority associated with each SCSI
address.
Table 2-1. Data Access Priorities for SCSI Addresses
Highest Priority 7 Adapter
| 6
| 5
| 4
| 3
| 2
| 1
| 0
| 15
| 14
| 13
| 12
| 11
| 10
v 9
Lowest Priority 8
2-4
4mm DDS-2 Tape Autoloader Installation and User's Guide