Spare Parts

MCU Board from an Addams Family

MCU Board from an Addams Family

Received an MCU Board today having won it on eBay. Apparently the board had been working before it was taken out of an Addams Family pinball, but still sold on the understanding that it was “defective” as the seller couldn’t test it.

My first impressions of the board weren’t good: firstly it was very dusty, secondly there were cobwebs on some of the pins. And finally, many of the pins on the connectors were bent. Even the component legs on the rear of the board were bent! To me it seemed that the board had been stacked with other boards for some time in a not-to-clean environment.

So having straightened up the pins, blown off the dust and cobwebs and putting a new L-7 eprom into the board,  I built the board into my pinball. At switch-on the machine fired-up. A good start. But then I tried to play a game, but I couldn’t. The pinball claimed that there weren’t any pinballs in the machine, but there were. This is where the problems started…..

Trying to go into the test menu was a nightmare. Firstly the ‘up’ button wasn’t working; secondly the menu kept on going into the help menu. Eventually I was able to establish that row 7 of the switch matrix wasn’t registering properly (which would go some way to explain why the machine thought there were no balls in the machine, as the outer trough switch – which switches when a ball is ready to be fired into the shooter lane – would not register a ball).

Also the display was acting erratically, with some frames incorrectly displayed and some letters missing.

I haven’t given up here yet (I am still in contact with the vendor) but think (hope?) it could just be a pin-to-pin contact problem.

Building my original MCU Board back into the pinball returned everything back to its normal working state (fortunately). Actually in retrospect, I’m guessing I could have done some damage to my pinball with this board. Thankfully, I didn’t.

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