Re: Please help with A3000 SCSI disk problem

["Kevin P. Neal" <kpneal%pobox.com@localhost>]

At 01:12 AM 5/17/97 -0500, Larry wrote:
>1. My SCSI termination isn't right. All 3 drives are internal, and I
>have nothing connected to the external SCSI port. The drive order from
>the motherboard is: Compaq, Maxtor, Seagate(terminated). I don't have
>specs on the Compaq drive, and it doesn't have the resistor pack holes
>I'm used to. I don't think it's terminated, but I'm not positive. If it
>were terminated, wouldn't the other two drives be invisible?

How long is the cable? How did you fit these three drives in the case?
How much space is on the cable between the drives? Between the board
and the first drive?

Are the resistor packs on the motherboard, terminating the chain at the
board? (these packs are right around the SCSI connector and chip)

Improper SCSI termination tends to cause problems that aren't that easy
to just categorize. It might cause drives to not show up. It might cause
drives to sometimes not show up. It might work fine. It might work fine
for some combinations of drives. It might lock your SCSI bus on boot. It
might work fine with some orders of drives on the bus. It might work fine
but have lots and lots of transfer errors (that don't get reported to you
by some drivers). 

The Compaq drive might have jumpers for termination. I suggest you get the
jumper settings from Compaq and then see if the drive is terminated. 

It also might be a problem with some drives just not getting along with other
drives on the bus. For example, my roommate has a terrible time getting
his Quantum hard drive to work on a bus with his Exabyte 8200 on his Sun 4/300.
He tries and tries and tries, and it just won't work. He has problems with
some drives not getting along with a DEC 1x CD-ROM drive. He just has problems.

>2. The prototype chip doesn't work with the NetBSD 1.2.1 SCSI drivers.

The prototype chips are the "A" chips. Has anybody ever tried a "B" chip?
It's supposed to be pin compatible with the A chip. Anybody even thought of
attempting to think about it?
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