19 Jun
2007
19 Jun
'07
3:30 p.m.
Of course the
system now still won't boot (I can hear the drive
head move, and then the RL02 FAULT light comes on) but it's likely
the OS/8 image got clobbered when the chip failed and the CPU
started writing to odd places.
Hmm... I don't think filesystem problems will cause the Fault light to
light up, just problems within the drive. You may need to trace back all of the causes that sum up to "Fault" to
see what's going on.
The way I always trace FAULTs of this nature is to grab the RL02 printset
and look at the DDrive Logic PCB scheamtics. It's clear from that
there's effectively a big OR gate that comines a lot of different signals
to turn on the FAULT light. I run a logic probe over each in turn to see
which is the one that's asserted, then trace back from that.
-tony