Compaq TruCluster Server AA-RHGWB-TE, Руководство пользователя

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but you would waste a disk slot and it would not work with a KZPBA-CB if
there are any UltraSCSI disks in the storage shelves.
The following sections discuss the DWZZA and DWZZB signal converters
and the DS-BA35X-DA personality module.
9.1.2 Using the SCSI Bus Signal Converters
The DWZZA and DWZZB signal converters are used in the BA350 and BA356
storage shelves. They have removable termination. The DS-BA35X-DA
personality module is used in the UltraSCSI BA356. It has switch selectable
differential termination. The single-ended termination is active termination.
The following sections describe termination for these signal converters in
more detail.
9.1.2.1 DWZZA and DWZZB Signal Converter Termination
Both the single-ended side and the differential side of each DWZZA and
DWZZB signal converter has removable termination. To use a signal
converter, you must remove the termination in the differential side
and attach a trilink connector to this side. To remove the differential
termination, remove the five 14-pin termination resistor SIPs (located near
the differential end of the signal converter). You can attach a terminator to
the trilink connector to terminate the differential bus. If you detach the
trilink connector from the signal converter, the shared SCSI bus is still
terminated (provided there is termination power).
You must keep the termination in the single-ended side to provide
termination for one end of the BA350 or BA356 single-ended SCSI bus
segment. Verify that the termination is active. A DWZZA should have
jumper J2 installed. Jumpers W1 and W2 should be installed in a DWZZB.
Figure 9–1 shows the status of internal termination for a standalone SCSI
signal converter that has a trilink connector attached to the differential side.
Configurations Using External Termination or Radial Connections to
Non-UltraSCSI Devices 9–3