My Forth board was working unreliably recently. I left it for a while, but one evening I decided to get to the bottom of it. Inspired by BDD's POC RAM issue, I pressed on the board in various places, and it would reliably reset if I pressed on it, so there appeared to be a mechanical issue. It had been working reliably in the past so this was strange.

An inspection of the board did not reveal anything. All the chips are socketed, so the next logical step was to remove each one and see if it was seated correctly. The R65F11 appeared to be the most likely problem, so I took that one out first. And there was the problem (see the attached photo).

So this was much quicker to find out the problem than I expected, and the good news there was nothing wrong with the design. My sockets are those round ones that are maybe a little harder to fit larger IC's into, but the interesting thing is that the way the pins bent didn't leave any obvious signs when looking at them. Also interesting is that there was enough contact even with bent pins for the board to work at least some of the time.

One of those bent pins was the reset line, the other an address/data line.

That R65F11 chip is quite rare, so I was quite concerned that I had damaged it. I managed to straighten the pins and fit it correctly and it's been working ever since. I will be more careful with sockets in the future.

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x86?  We ain't got no x86.  We don't NEED no stinking x86!

I have a 6502 which until recently had a U-turn on the clock pin. That took a bit of straightening out. I hadn't noticed, because by some good luck the short double thickness end of the pin was making sufficiently good contact. I think it's the only time it's happened to me, but it used to be standard advice to watch out for pins which had bent underneath instead of landing in their sockets.