StorageWorks BA346-K Series, User Manual

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Configuring the Pedestal 3–3
3.3 SCSI Buses
The reliability of data transfers on a SCSI bus is a function of the following:
•
The bus transmission rate
•
The bus type (8-bit or 16-bit)
•
The maximum SCSI bus length (a function of the bus type, the transmission rate, and the
use of SCSI bus converters)
•
The total length of the SCSI bus (as measured from the host bus terminator to the pedestal
terminator)
Table 3–3 lists the maximum SCSI bus lengths and the recommended SCSI bus cables.
Table 3–3 SCSI Buses and Cables
Bus Type Transfer Rate Bus Length Recommended Cable
Width Type
Controller
Termination MT/s
†
MB/s Meters Feet
Order
Number Meters Feet
8-bit Fast Differential 10 10 25 82 BN21K–23
BN21L–23 23 82
8-bit Fast Single-ended 10 10 3 9.8 BN21K–02
BN21L–02 2 6.6
8-bit Slow Single-ended 5 5 6 19.7 BN21K–05
BN21L–05 5 16
16-bit Fast Differential
‡
10 20 25 82 BN21K–23
BN21L–23 23 82
16-bit Fast Single-ended 10 20 3 9.8 BN21K–02
BN21L–02 2 6.6
Note
MT/s (megatransfers per second) is the repetitive rate at which words of data are
transferred across a bus. The number of megabytes per second (MB/s) is
determined by the bus width (8-, 16-, or 32-bit) and the number of bytes per word
(1, 2, or 4, respectively).
†
Megatransfers per second
‡
BA346–DB deskside expansion pedestal.