>From: allisonp@world.std.com (Allison J Parent)

>Second, why scsi?  Why not IDE it's cheaper hardware, capable of better
>performance than the RQDX3/mfm drives and requires a simpler controller
>than SCSI.
[...]
>IDE offers a far lower cost interface.  It should be considered.

Just in case the usual SCSI vs. IDE flamewar is in danger of starting here,
I just want to point out that the Q-bus is far slower than either of them so
the transfer speed difference, if indeed it exists, doesn't matter.  Anyway
one argument I can see against IDE is the 18" max cable length (or whatever
it is, short anyway), but in a BA23 or BA123 that could be easily met (can't
use external shoeboxes though).  If you build a SCSI board that happens to
use a micro with Intellish timing anyway, a PIO IDE port requires just about
no hardware so why not add that on in addition to the SCSI.  A SMC37C65+
FDC chip also interfaces to Intellish buses with just an address decoder,
and needs just one resistor pack for the drive interface, so adding support
for a zillion RXxx disk types (including RX01 but not RX02) would be very
easy, I'd be happy to provide (80x86) driver code for that.

I've been meaning to build a board like this for ages and it would be great
to see someone else actually pull it off.  However let me point out that
the $200 price tag is highly unlikely.  DEC will want $100/board "protection"
fee just to not sue (assuming the card runs MSCP so as to be bootable), and
last time I had a multilayer board made we paid $70/each qty=20 for a board
that was a bunch smaller than a dual-height Q-bus board.  That's just for the
bare board, the parts add up to a few bucks (and you have to tie up a bunch
of cash in PCBs and parts to get decent qty discounts) and it takes an hourish
to stuff each board if it's done by hand.  It would be understandable to
expect some money for the weeks/months of development too, even if it is a
hobby project (which it need not be).

Maybe this would be a good time for the return of the Bare Board?

John Wilson
D Bit