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SCSI SWITCH II
Problem 3. SCSI Switch II appears to be working, but SCSI device does not
respond properly to system:
If possible, remove the SCSI Switch II. Then, if the device with the problem is
on a branch bus, connect that branch directly to the main bus; if the problem
device is on the main bus, either terminate the unterminated end of the main
bus or connect the main bus to one of the three branch segments. Now try
the same type of communication with that device; if the communication
succeeds, contact your supplier, because either there’s something wrong with
your Switch or you’ve hit a SCSI bug.
If the communication still fails, try these measures:
• Check power to all SCSI devices.
• Check the ID codes of all devices throughout the system and correct any
conflicts. On the SCSI bus, no two devices may have the same ID. With the
SCSI Switch II in place, you may be connecting two bus segments that
have similar ID codes. (To check and reset ID settings on your SCSI
devices, please refer to the manuals supplied with those devices.)
• Check your SCSI cables. Make sure that all Pin 1 markers are matched
(no cables are connected backwards). Make sure that all cables are in
working order. Interchange cable segments to test in other locations as a
process of elimination.
• The terminators on that bus segment might be bad. Try swapping in
replacements.
