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4 X 2 SCSI MATRIX SWITCH
5. Configuration and Operation
5.1 SCSI Cable Interface Requirements
The 4 x 2 SCSI Matrix Switch can be installed at any point on the SCSI bus. Always
use high-quality SCSI-2 or SCSI-3 cables for optimum computer performance and
reliability.
The SC123A differential switch contains 68-pin high-density SCSI-2 connectors
for 40MBps wide Ultra SCSI computers and peripherals. The maximum cable
distance should not exceed 82 ft. (25 m).
The SC122A single-ended/low-voltage differential switch contains 68-pin
high-density SCSI-2 connectors.
Low-Voltage Differential (LVD):
When operating with LVD devices, 80-MBps wide Ultra2 SCSI computers and
peripherals are supported. The maximum cable distance for LVD should not
exceed 25 meters (82 feet) total length.
Single-ended (SE):
When operating with SE devices, 40-MBps wide Ultra SCSI computers and
peripherals are supported. The maximum cable distance for SE should not exceed
6 meters (19.7 feet) total length.
Black Box offers standard and custom SCSI cables for connecting the SCSI
Switch to host devices and peripherals. Call Black Box Technical Support for
details.
5.2 Internal Terminator Selection
The SCSI Switch contains internal SCSI bus terminators for each port.
Termination is required at both ends of a SCSI bus for proper operation. Each
port can have their internal terminator enabled or disabled from the front-panel
display and keypad.
Refer to
Figure 5-1
to select internal termination.
NOTE
Data errors will result if more than two sets of terminators are installed
on any SCSI bus (See Figures 2-1 and 2-2).
Summary of Contents for SC122A
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