Bill, you seem well-versed on this subject, so perhaps you can tell
me if the ability of ultra to double the clock rate means that ultra
would probably support higher bus speeds . . . such as 75 mhz or
83 mhz.

Thanks,

Lance

On Sat, 28 Feb 1998 23:11:00 -0500, Bill Cohane <[log in to unmask]> wrote:

<snip>

> In wide SCSI, two bytes is sent along 16 data wires that are in parallel.
> For each clock cycle, two bytes can be transferred. So the data transfer
> rate is doubled in wide SCSI by doubling the width of the data path
> (doubling the number of data lines). There are also more ground wires (for
> shielding) and more control lines. With wide SCSI, twice as many SCSI devices
> can be handled by adding another "addressing" bit. Yes, the cable is wider
> for wide SCSI. (68 lines compared to 50.)
>
> Note that in *ultra* SCSI, the data transfer rate is doubled by doubling
> the clock rate. (Twice as many signals moving along each line each second.)
> Wide and ultra would give four times the data transfer capability of narrow
> (non ultra) SCSI.
>
> Regards,
> Bill
>