AlphaStation 200 NVRAM Problem

Robert Jarratt robert.jarratt at ntlworld.com
Sat Apr 23 12:01:11 CDT 2016


> -----Original Message-----
> From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Robert
> Jarratt
> Sent: 23 April 2016 17:34
> To: 'General Discussion: On-Topic and Off-Topic Posts'
> <cctalk at classiccmp.org>
> Subject: RE: AlphaStation 200 NVRAM Problem
> 
> >  But from the discussion referred I gather DROM outputs its
> > diagnostics to this port too and you might be able to learn what
> > exactly about NVRAM it complains.  Also you might be able to correct
> > configuration, e.g. by
> poking at
> > NVRAM or elsewhere appropriately; notice that the manual also suggests
> > you might be able to bypass the DROM sequence and go to SRM/ARC
> > directly, which might help recovery too.
> >
> 
> Having checked the manual I think you may be referring to the following
> text:
> 
> " When the SROM code has completed its tasks, it normally loads the DROM
> code and turns control over to it. The SROM checks to see if the DROM
> contains the proper header and that the checksum is correct. If either
check
> fails, the SROM code reads a location in the TOY NVRAM. The location
> indicates which console firmware (the SRM or the
> ARC)
> should be loaded.
> When the console firmware is loaded, the header check and the checksum
> are checked. If either is in error, the SROM code jumps to its
mini-console
> routine. With the appropriate adapter, you can attach a terminal to the
CPU's
> serial port and use the mini-console.
> Typically, this port is used in the manufacturing environment."
> 
> To get this sequence to work needs two things though. First I have to
create
> a DROM error. The DROM seems to be fine. Perhaps I could remove the
> DROM chip as it is socketed to provoke the error.
> 
> However, then it says it checks the TOY NVRAM for which firmware to load.
> The battery was flat, so the TOY NVRAM won't have this info. Hopefully it
will
> default to one of them.
> 
> Still, if I had the mini-console adapter, that would probably really help.
> 
> Regards
> 
> Rob


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 will have to see if the NVRAM is now populated and whether it will
continue to work with the DROM installed.

Thanks!

Rob



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