23 Apr
2016
23 Apr
'16
11:21 a.m.
-----Original Message-----
From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Maciej W.
Rozycki
Sent: 23 April 2016 18:57
To: General Discussion: On-Topic and Off-Topic Posts
<cctalk at classiccmp.org>
Subject: RE: AlphaStation 200 NVRAM Problem
On Sat, 23 Apr 2016, Robert Jarratt wrote:
easier,
and
Well! I took out the DROM and switched it on
again. The machine
bleeped at me, but then it gave me a console and I was able to boot VMS!
I'm glad that it worked, this will certainly make further diagnostics you have a usable machine anyway.
Yes that is exactly the code I get on the LEDs.
I will have to see if the NVRAM is now populated
and whether it will
continue to work with the DROM installed.
First: to double-check, how did you know it was a NVRAM failure, did LEDs
show DC (xxox xxoo)?
Second: it may also be that DROM itself is faulty, a bit may have flipped
for
example; NB this is UV EPROM, so things happen. Maybe
someone can
share a known-good image.
When I put the DROM back the failure returned. So it is either a bad SRAM, a
short/open somewhere, or the DROM code itself. I have a PROM programmer, but
it is only for DIP packages, I don't have the facilities to read a PROM in
this type of package. I will have another look round for any obvious
problems on the board, but it looked OK to me when I checked. Getting the
SROM diags out might help too, I will have a look at that.
Regards
Rob