ESDI, MSCP, RSX11M, TK50's, etc.

From: CLASSICCMP_at_timaxp.trailing-edge.com <(CLASSICCMP_at_timaxp.trailing-edge.com)>
Date: Sat Oct 3 09:08:33 1998

>of my parts and tapes. I discovered that I've got two ESDI controllers,
>instead of the one that I knew about, one is a Emulex QD21 which I found
>the manual online for, the other a "Webster WQESD" which I have the manual
>for.

Which version of WOMBAT is on your WQESD? You can identify this by either
looking at the sticker over the firmware EPROM, or if this doesn't tell
you, by starting up the on-board diagnostics. Certain versions of Wombat
do not interact well with RSX-11M's DU driver. Very often, older versions
will work better than certain newer versions. Most of my systems are running
WOMBAT V2.3, which works fine for me with the PDP-11 OS's (but *not*
with later VMS versions.) WOMBAT V2.3 does work a little strangely with
2.11BSD's MSCP driver when you do a "shutdown -r", having something to
do with the CPU doing a bus reset while the controller is still doing a write.

I've never attempted to compile a list of which versions of the PDP-11 OS's
do and do not work with various WOMBAT versions, but perhaps it would
be worthwhile to build such a table. As it is, I just pop in different
firmware EPROM's until it works.

It's also worth checking that the WQESD really does respond to the CSR
you think you've set it to. The table in your manual is probably correct
for the most common address configuration PAL, but there are several
dozen different address configuration PAL's that were made for special
applications. If you have one of these non-standard PAL's, you'll
probably be much better off to put the WQESD at 17772150 and the floppy
controller at some other CSR.

---
 Tim Shoppa Email: shoppa_at_trailing-edge.com
 Trailing Edge Technology Voice: 301-767-5917
 7328 Bradley Blvd Fax: 301-767-5927
 Bethesda, MD, USA 20817
Received on Sat Oct 03 1998 - 09:08:33 BST