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Joined: Aug 2005
I was given 2 non-working 9810s at the same time, the donor suggested I might try swapping boards around to get one of them working.
Needless to say I didn't waste time doing this (and actually, it wouldn't have helped anyway -- the 'better' machine had a fault on the I/O interface PCB, and that board, along with quite a few others had problems in the other machine). Instead I figured out how to fix them properly, fixed one, then, I will admit, tried the boards from the other machine in it one at a time to see which had serious faults. I then debugged those the old-fashioned way.
98x0 machines are a bit hard to debug becuase they're bit-serial, so everything is changing all the time :-). But given a logic analyser (the HP logicDart is ideal!), it's quite possible to find faults.