[rescue] DSBE/S

[James Lockwood]

On Tue, 23 Apr 2002, Joshua D Boyd wrote:

> This is what I need for the RSM-214, right?  After hitting buy it now, I
> noticed that the seller describes it as a 68pin narrow single ended
> differential controller.  The associated picture shows the card with the
> words differential scsi above the 68pin plug, but the logo next to the
> words doesn't look like the normal differential logo.
>
> Seller also says "Part Number(501-1902)/Kit Number X1052A"
>
> So, the handbook says that it is a differential scsi/ethernet card, and not
> much else.
>
> Now, my understing is that differential is always wide, and differential
> and single ended are mutually exclusive.  Did I just do something stupid?

Differential is not always wide.  Differential (HVD) can come in just
about any flavor that SE can.  Fast/narrow/SE was originally not in the
SCSI-2 spec, Fast/narrow/diff was the mandated path to go down (far fewer
cabling issues than SE).  Unfortunately the installed base of SE
controllers and devices prevailed.

The DSBE/S is a narrow, 68-pin differential controller.  The external
connector is 68-pin (normal for wide SCSI) but the controller itself is
limited to 8-bit transfers and 8 SCSI IDs per bus.

-James