This article was previously published under Q168094
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After you attach a 50-pin or Centronics SCSI-2 hard disk, scanner, tapeDrive, or other device to a 68-pin SCSI-3 interface, your computer may stopresponding or not respond when accessing SCSI bus. You may or may not seeany events in the event log indicating a problem.
Obtain a proper SCSI-2 to SCSI-3 conversion cable or terminator.
For additional information, click the article number below to view the article in the Microsoft Knowledge Base:
101352 Properly Connecting SCSI Devices to Windows NT
A SCSI-2 device uses a low control byte, but SCSI-3 devices have both ahigh and a low control byte. When going from a SCSI-3 interface down to aSCSI- 2 device, the SCSI-3 high byte needs to be terminated while lettingthe low byte pass through (see Diagram 1). Most SCSI-3 to SCSI-2 cables donot have proper termination and need a special adapter for the high byte toterminate. Unless the documentation that comes with the conversion cablestates that it terminates the high byte, proper termination will not happenand possible data corruption can occur.
See "Connecting 8-Bit and 16-Bit Devices to an Adaptec Wide Host Adapter".
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