25 Sep
2004
25 Sep
'04
6:07 p.m.
All good advise - assuming that it's running
(clocked), and the address/data
bus looks ok (being driven, no signs of contention etc.), data being fetched
from the ROMs, I would probably next check the ROM content against the image
on funet (I've seen a number of these ROMs go bad).
Not a bad idea. Also, if iy uses 2114 RAMs, susepct them on sight ;-). I
think these units initialise the I/O devices fairly early on, and the
fact that you LEDs are stuck in the wrong state would seem to indicate
this is not happening.
Opened it up this morning - unfortunately, it is very badly corroded inside,
and the drive unit itself shows a LOT of rust.
I would now suspect any IC sockets, and mayeb even leakage between PCB
tracks.
-tony