>On Mon, 11 Feb 2002, Julius Sridhar wrote:
>
>> A narrow device will not slow down a wide bus to narrow width. But a
>> 10 MHz device will slow down a 20 MHz SCSI bus to 10MHz.
>
>You're contradicting yourself here. Either that or the semantics of your
>sentence are confusing :)
Both the 20Mhz (Ultra) and 10 Mhz SCSI buses are narrow.
Standard SCSI runs at 5 Mhz, Fast-SCSI at 10 Mhz, Ultra at 20Mhz and
Ultra2/Wide is 40Mhz. The various versions of Wide go up to 160Mhz
and 30 devices now. 20Mhz and below is still narrow width, just
different speeds. The bus will slow itself to the speed of the
slowest item on the bus. To put a narrow item on a wide bus requires
some sort of adapter so the narrow item only changes the speed of the
bus, not the data width of the whole bus.
Jeff
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Received on Mon Feb 11 2002 - 18:16:53 GMT