[rescue] Sun 375-0006 SCSI Controller

[Jonathan Patschke]

On Fri, 11 Dec 2009, Earl Baugh wrote:

> Did some digging thru the pile of cards here and realized I have a Sun
> 375-0006 controller (which is a Dual Differential Ultra/Wide SCSI
> (UDWIS/P)(HVD) controller) It's listed as compatible with the Ultra 5,
> 10 and Blade 100.
>
> But I haven't been able to find if there are any internal disk options that
> I could boot from with this.

The short answer is "no".

The longer answer is that any 68-pin differential (not LVD) disk will
work.  Those controllers were usually used to talk to disk arrays (which
usually used SE signaling internally, but differential back to the host)
or tape drives.

> I know it was used to connect to a storage array in the past, but not
> sure if I could use it as the internal SCSI controller and boot from
> it...

If you can find a disk, certainly.  However, 5V differential disks haven't
been commercially viable since LVD came along years and years ago, and you
can't use single-ended or LVD disks with a differential controller.

> Would say a Fujitsu MAP3367NC or Segate ST318203LC work?  I've next to no
> experience with HVD stuff..

A differential controller requires differential devices connected to it.
I have never heard of a differential disk with an SCA connector (they're
all either single-ended or low-voltage differential) as both of those two
disks have.

Seagate are particularly nice in their model numbers, as they tell you
everything you'd want to know about the disk.  "ST3" at the beginning
means it's a Seagate 3.5" half-height disk, and "LC" at the end means it's
an LVD device with an SCA connector.

All Seagate differential disks that work with that controller will end in
"WD" (wide, differential).  These will be old, relatively rare, slow
(20MHz bus speed or slower) probably somewhat expensive, and 18GB or
smaller.  You'll also need differential bus terminators, which are
completely incompatible with the single-ended and LVD terminators you
almost-certainly have.

Why do I call them "differential" instead of "HVD"?  Because that's what
they were called when they were still made.  It'll be a very rare device
that is actually labeled "HVD".  If it says "differential" and doesn't say
"LVD", it's what some people now call "HVD".

-- 
Jonathan Patschke  ) "Science is what we understand well enough to explain
Elgin, TX         (   to a computer.  Art is everything else we do."
USA                )                                    --Dr. Donald Knuth