Setting Scsi Switches - DEC MicroVAX 3100 Owner's Manual

• Two devices may have the same identifier only if they are on different
busses.
• Each SCSI bus must be terminated. Add a terminator to an unused
SCSI port.
Table 8-1: SCSI IDs for MicroVAX 3100 and VAXserver 3100 sys-
tems
SCSI-A Internal Bus
7 Reserved for highest priority device
6 SCSI-A controller
5 TZ30, RZ23, RX23
4 Unused
3 RZ23 (system disk)
2 Unused
1 Unused
o
Unused
SCSI-B External Bus
7 Reserved for highest priority device
6 SCSI-B controller
5 TK50Z expansion box
4 RRD40 expansion box
3 RZ23
2 RZ23
1 RZ55 expansion box
o
RZ23, RX23
NOTE:
Proper operation of the SCSI bus requires that high-quality,
properly configured cables and connectors be used to connect all
devices. It is recommended that only DIGITAL-supplied cable assemblies
intended for interconnecting SCSI devices be used. This ensures that
the impedance characteristics, signal propagation velocity, inductance,
capacitance, cross-talk, grounding, conductor pairing, and shielding meet
the requirements for proper operation of the bus. In addition, it is
recommended that all units on the SCSI bus be powered from a common
AC power source. The proper operation of any SCSI bus that uses
cable assemblies not supplied by DIGITAL, or that are not configured in
accordance with DIGITAL's recommendations, is not guaranteed.
8.3 Setting SCSI Switches
SCSI IDs (addresses on SCSI bus) and the corresponding switch positions
shown in the following tables are the possible IDs and switch positions for
each expansion box.
SCSI IDs
B-3