[Sunhelp] Quick SCSI question

[james]

On Tue, 7 Dec 1999, Gregory Leblanc wrote:

> Just to make sure that I'm not smoking crack (tm), somebody check this SCSI
> cabling spec real quick?
> 
> 
> ---------------                    -----------
> ------------
> | Wide SCSI   |__ Hd68-HD86 cable__| Wide AIT|__HD86-Centronics-50__| Narrow
> |__Active term
> | Controller  |                    | drive   |                      | SCSI
> DLT |
> ---------------                    -----------
> ------------

It got screwed up a bit in transit (too wide I expect).  Anyways, you do
have a problem, you need to terminate the high bits in between the AIT
drive and the DLT.  Either a special terminating cable is needed or you
need to tell the AIT drive to terminate them (but not the low bits).

> I can't see any problems, but I'm not 100% sure, so I'm asking.  I expect
> that all devices will have narrow IDs, but the AIT could have a wide, if we
> added a bunch more drives.  Thanks,

Wide SCSI adds an additional line for SCSI ID (giving you 4 bits instead
of 3).  If you use a high ID (like 10) then it can conflict with narrow
SCSI ID 2 on the same chain.

-James