On Sun, 9 Feb 2003, Brian Chase wrote:
> On Sun, 9 Feb 2003, Chuck McManis wrote:

> > The bad news however is that all lights on 7-4 means a main board POST
> > error. My suggestion would be to try pulling memory simms to see if you can
> > get a minimal system alive. If that doesn't have any effect (it won't
> > unless the first SIMM is bad) then the next candidate is that your power
> > supply isn't supplying all of the correct values.
>
> Ah.  Okay.  Just a little while ago I tried getting some different
> behavior out of the system by pulling the SIMMs completely, and then
> attempting to shuffle them a bit.  Unfortunately I didn't have any luck
> with that.  As for the power supply going, that would make me sad.
> At least I can test that pretty easily.  I'll try swapping in known
> good supply and see what happens.

Nope.  A known good power supply produces the same behavior, and the
power supply in question works just fine in another system.  So that
leaves something on the main board itself... which looks to be mostly
surface mount components.  ugh.

Are you /sure/ about the PROMs not being write-enabled like the
VS4000/90?  I did find the following page that covers a similar set
of LED codes for the VS3100:

   <http://home.iae.nl/users/pb0aia/vax/3100leds.html>

The 1111 "state" of LEDs 7-4 seems to indicate it in the POST as you
mentioned.  At the bottom of the page, there's a table of "substate"
values; the table shows the 1101 "substate" corresponding to the "NVR"
subsystem.  I'm not quite sure what NVR stands for, but one might
reasonably guess "Non-Volatile RAM".  So, my "1111 1101" /might/ be
interpreted as something gone amuck with a basic POST check of the
NVRAM.  What exactly that check would be, I've no idea.

Then again, maybe it's just a concidence--a meaningless bit of garbage
consistently triggered during a failed POST.  Or maybe the patterns for
the VS4000 are different than those for the VS3100.  If I could find my
IC extractor, I'd be able to gather empirical evidence by swapping in
known good PROMs.

-brian.