P-Cable To A-Cable Adapter - Sun Microsystems storagetek sl500 Reference Manual

P-cable to A-cable Adapter

P-cable to A-cable Adapter
Problems can occur when you mix SCSI devices that use P-cables with devices that
use A-cables:
The terminator power (TERMPWR) requirements for devices using a P-cable
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have been increased to support a 16-bit data bus. Devices using an A-cable and
supporting the SCSI-1 standard may not supply sufficient TERMPWR to operate
on the SCSI bus.
Two reserved lines on the A-cable (23 and 24) must provide TERMPWR to P-
cable lines (33 and 34).
When buses of different widths are connected on the same bus, data bus signals
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from wider cables are left open and must be terminated using an adapter.
When connecting a P-cable to an A-cable for eight-bit (narrow) data transfers, the
following signals are left open. A special adapter must terminate these signals:
+DB (15-8)
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+DB (P1)
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-DB (15-8)
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-DB (P1)
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The adapter is part number 10148010.
12 SL500: Interface Reference Manual • July 2008 Revision: F • 96122