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[GFRAZIER at ausvm6.vnet.ibm.com]

STEVE FINCH'S QUESTION ON SPI:

Steve asks several questions and I hope I can answer one of them:

Steve Finch wrote:
 .....
>This led me to review all of the differences between Fast and Slow timings
>in Table 10.  Can anyone explain why the Transmit Hold Time changes between
>Fast and Slow, but the Receive Hold Time doesn't?  Or why the Transmit Hold
>Time varies between the two modes, but the Transmit Setup Time doesn't?

These times are the way they are in order to ensure that a SCSI-2 slow
device can interoperate with a SCSI-3 slow device. As some may recall,
I pointed out this problem about a year ago and the committee voted to
fix the problem. If needed, I will attempt to restore a note I sent to
the reflector with details describing the reason for the change, but in
summary, it turned out that the only time which needed to be different to
ensure SCSI-2/SCSI-3 interoperability in slow mode was the transmit hold time.

                                           Giles Frazier
                                           IBM Austin
                                           gfrazier at ausvm6.vnet.ibm.com