>
>  I have asked our DEC/Compaq/HP service person if he could find out
> anything through his channels.

All the VS4000 systems (including VLC IIRC) and the NVAX=20
based MicroVAX 3100 systems have firmware in flash. Updates
were available in various forms: at least a MOP bootable and an
OpenVMS executable were available - there may have been other
forms. The only VAX system for which I recall firmware upgrades
being available publically were (some of) the VAX 7000 systems.
In fact, when last I looked, this upgrade (and those for pretty much
all the Alphas) could be found with a search on the OpenVMS web
page.

I did ask (some time ago) whether the firmware could be released=20
as part of the Freeware CDs, but it needed approval. It may happen,
or it may not.

>  Unfortunately, the AMD chip doesn't work that way.  You have to erase
> the chip to all ones, and then clear the bits to program it.  Once a =
bit
> is cleared, it can only be set by erasing the entire memory.

That's certainly true for all the AMD chips for which I have
had to write flash upgrade code (never on a VAX though).

>  I've tried a simple 32 bit sum, and didn't get any useful result.
> Somewhere in all the code in those images should be the test it uses =
to
> verify the PROM.  I've disassembled it with objdump and scanned it =
very
> briefly, but didn't spot anything.  The objdump output is 145,000 =
lines,
> which is a lot to grovel through, and objdump probably messes up some =
of
> the disassembly.

If you look at the KA655 tech manual, on p4-81 it shows that the
EPROM checksum does not live at the end of the EPROM. This
is admittedly a much older system (EPROM, no flash) but the=20
same could well be true of the VS4000-90.


Antonio