symbios logic J21971S-0398, Installation Manual

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Host Interface
SCSI Interface
Revision A, March 1998 Technical Reference 61
Table 9 Command Module SCSI Interface Cables
16-Bit Vs. 8-Bit Connections
Although the command module
is a 16-bit unit, it supports either an 8-bit (50-pin) or 16-bit (68-pin)
differential, SCSI-2 interface. The interface connectors and type of
cables you use depend on the following:
●
What kind of host SCSI bus you are connecting the command
module to (an 8-bit or 16-bit bus)
●
Where you are connecting the command module on the bus
You can install this command module on either an 8-bit or 16-bit host
SCSI bus as long as you follow these guidelines:
●
Installing command module in middle of a 16-bit bus — You
can install the command module anywhere between the first
and last device on a 16-bit bus simply by attaching the SCSI
cables to the appropriate host SCSI connectors on the back of the
unit. The incoming SCSI cables attach to the IN connectors. The
SCSI cables on the OUT connectors attach to the next device on
the bus.
●
Installing command module at end of a 16-bit bus — If you are
installing the command module as the last device on a 16-bit
bus, you must connect the incoming host SCSI cable to the IN
connector, then install a terminator on the corresponding OUT
connector. For more information on terminators, read
“SCSI
Terminators” (next section).
●
Installing command module on an 8-bit bus — If you intend to
connect the command module to an 8-bit host SCSI bus, you
must install the command module as the last device on the
bus.
You cannot install this command module in the middle of
an 8-bit SCSI bus. The incoming SCSI cable attaches to the IN
' 5 3- ## $% *
16-bit 1415-C078-xxxx
1
68-pin, HD, 180
o 2
68-pin, HD, 180
o
16-bit 1415-C086-xxxx 68-pin, HD, 180
o
68-pin, HD, 180
o
PLENUM
3
8-bit 1415-C080-xxxx 68-pin, HD, 180
o
68-pin, LD, 180
o
8-bit 1415-C076-xxxx 68-pin, HD, 180
o
50-pin, HD, 180
o
8-bit 1415-C085-xxxx 68-pin, HD, 180
o
50-pin, HD, 180
o
PLENUM
16-bit 1415-C078-0023 68-pin, HD, 180
o
2.3 M (7.5 ft) channel-to-channel daisy-
chain
16-bit 1415-C078-0004 68-pin, HD, 180
o
0.4 M (1.3 ft) controller-to-controller daisy-
chain
1
xxxx = length of cable in tenths of a meter
2
180
o
= angle that cable connector exits the unit
3
PLENUM = used for air plenums (required for cables over 10 ft. used in air plenums)