Subject: Re: Any spare Qbus cdrom cards for an RRD42 drive around?
To: der Mouse <mouse@Rodents.Montreal.QC.CA>
From: Brian Chase <bdc@world.std.com>
List: port-vax
Date: 12/20/2000 14:17:32
On Wed, 20 Dec 2000, der Mouse wrote:

> Does anyone know of a "native" Q-bus SCSI interface, ie, one that
> doesn't hide its SCSIness?  It wouldn't be bootable without replacing
> all the ROM code, but it would still be useful nonetheless (at least
> to retrocomputing geeks like us :-).
>
> If not, has anyone considered making one?  The Q-bus is simple enough
> to interface to with discrete logic, and surely there's some SCSI chip
> that could do the interfacing.  (Heck, you can almost do SCSI out a
> parallel port, with appropriate software hackery - though I shudder to
> think what it would do to throughput.  Still, it could be better than
> NFS over a DEQNA.)

There is a guy in the Ukraine who's designed a Q-bus based PIO mode IDE
controller.  ftp://zane.brouhaha.com/pub/dsu/ I'd asked him sometime last
year about the possibility of paying him for an example board or two, but
he wasn't willing (or maybe able?) to build more of them.  I think some of
the parts were kind of unusual or hard to come buy.

Perhaps someone with a little more electrical/computer engineering
knowledge could redesign the boards with more comonplace components.

I don't know of any projects to make native SCSI controllers.  As long as
we're talking wishlist stuff here... How about a DMA based IDE controller?
Or maybe a Q-bus USB controller.  Or how about a Q-bus to PCMCIA bus
bridge card?

Some of this has been discussed on this list before.  So far, I don't
think anyone's been able to come up with a way to do this cheaply.  I
think the Q-bus/PCMCIA bridge is good idea given that it opens a whole
world of useful and modern controllers for use in the VAX, but I imagine
that's a pretty non-trivial task.

-brian.
--- Brian Chase | bdc@world.std.com | http://world.std.com/~bdc/ -----
   You can't FLING fun or SLAP fun or even MASSAGE FUN INTO someone,
                       but you can POKE fun.  -- K.