Anyway - the original problem is gone. With the (half)
new RAM I'm now
getting what at least appears to be a proper fault indication on the
LEDs: both DSR and POWER/FAULT are flashing. This combination isn't in
the user manual so my guess is it's failing the POST. If any of the
Maybe soemthing like 'RAM Error' :-)
That was my first guess too. Running the ROM through a simulator and
forcing the RAM test to fail confirms it. The problem? I'd managed to
OK...
gouge out a bit of track while removing the ICs - just
so happens it
was one of the very tracks connecting /all/ the RAM to the address
bus, so checking for continuity between the sockets I'd soldered in
didn't reveal the problem.
So I fixed that and robbed a couple more 2114s from another machine.
So all RAM is replaced but, lo and behold, ONLINE and CSR are back
with a vengeance. So I'm basically back to square one, although not
Ah, but you've confirmed that the processor is doing something, and that
it's executing the firmware (at least partially). If not, then the RAM
failure, (albeit a man-made one) would not have been detected. Surely
that is a staep forward.
> > I
seem to have dumps of 147E4 and 148E4 here...
...
I'll get them on my way to you...
Many thanks! You may also want to send them on to Pete Turnbull for
inclusion in his DEC ROM archive.
You are welcome to forward thenm on to him. I have no claim over them.
-tony