Old Unibus PDP-11 XXDP diagnostics

From: Ashley Carder <wacarder_at_usit.net>
Date: Tue Dec 21 11:32:17 2004

> On Tue, 2004-12-21 at 08:27, Ashley Carder wrote:
> > Does anyone have any info/documentation on the XXDP diagnostics for
> > older PDP-11 systems and peripherals? I'm looking in particular for
> > the 11/40 (11/35), RK05, DZ11, RL02, MM11 core memory, RX01, RL01
> > diagnostics. I have found some info on Henk's site, but would like to
> > know if anyone has a comprehensive list and hints on how to run these,
> > what the output means, how to answer the prompts, etc.
> >
> > I have created RL02 packs with XXDP 2.5 and XXDP 2.2 and I can boot
> > and run stuff from these packs. It appears that the 11/40 diagnostics
> > are on XXDP 2.2, but not on XXDP 2.5. I have an old 1976 DEC field
> > rep troubleshooting guide that refers to various MAINDECs, which seem
> > to have been the diagnostics prior to XXDP. Is there a list somewhere
> > showing what the XXDP equivalents of the old MAINDECs are?
>
> OK, the "magic decoder ring" for converting the MAINDECs to XXDP names
> is quite simple. The MAINDEC # is of the form:
> MAINDEC-11-Dxxxx-*
>
> To convert this to the XXDP diagnostic name keep only the xxxx part of
> the MAINDEC #. To run it, do:
> R xxxx??
>
> The first letter in the diagnostic name tells you what processor it's
> for. If I remember correctly C=11/40, Z=any
>
> There's a document that tells all about it (but I can't remember where I
> found it at the moment).

I have a copy of the MAINDEC naming convention magic decoder in the
"PDP-11 Mainframe Troubleshooting Guide". I just didn't know how to
make the conversion from MAINDEC name to XXDP name.
 
> The pack images that you're talking about don't have the correct memory
> diagnostic, but I've found that ZMSDD0 (wow! from memory...can you tell
> I've used it a bunch?) works OK enough to be able to find bad memory and
> you'll know when you hit bad memory. I've also found that having a
> hardcopy terminal is preferable to a CRT when you're getting failures.
>
> If a diagnostic loads and then gives you a prompt like "DB>", START is a
> good choice as a response.
>
> >
> > Any help would be appreciated. I want to exercise my 11/40 and
> > attached peripherals and see if any subtle gremlins are lurking
> > anywhere within. Everything appears to be working perfectly with the
> > exception of one of my three RK05 drives that I knew was problematic.
> >
> > Ashley
> --
>
> TTFN - Guy
>
Received on Tue Dec 21 2004 - 11:32:17 GMT