Daniel A. Seagraves wrote:
> 
> What's the actual drive?  Can I hang a normal PC type FDD off here?
> I'm getting sick of trying/retrying/inevitably failing with RD disks...
> I've tried 4, and all 4 have failed...  I got a RD33 to work from the ROM
> standpoint, but when NetBSD boots, it can't write to the drive for nothing.
> I get all sorts of errors that look like bad sectors, even though I
> formatted it on the 2K fine...
> I have a couple more drives to try...
> Is there any special mod required (BEsides a new format) to get ex-PC drives to
> work in uVAXen?
> -------

Well, it's all probably NetBSD's fault if the drives work with the ROM. 
We *really* need bad block revectoring on the VS2000.  For a drive to
work it has to have either *no* bad sectors or you have to find the bad
sectors and make sure they aren't used.  (this could be an annoying
activity)

Anyways, any MFM drive should work.  You just need to set the drive ID
to 3 and format it in the VS2000.  The formatting is the tricky thing
because you'll get asked for all sorts of obscure parameters.  They are
explained in the MicroVAX FAQ and some other places, but there's some
incorrect information about it out there as well.  I figured out that
the number of LBNs is the capacity of the disk minus:
RBNSIZ + RCTSIZ * RCTNBR + XBNSIZ + DBNSIZ + 1_CYLINDER

BTW.  Where can I find the format of the RCT and the RBN locations.  The
driver has the on-disk geometry block defined, but for bad block
replacement one also needs to know about the RCT.

-- 
|  Boris Gjenero <bgjenero@undergrad.math.uwaterloo.ca>              |
|  Home page:  http://www.undergrad.math.uwaterloo.ca/~bgjenero/     |
|  "Luke, you're going to find that many of the truths we cling to   |
|  depend greatly on our own point of view." - Obi-Wan Kenobi, ROTJ  |