My recently acquired Pinbot is missing segment p on the alpha numeric displays. I replaced a resistor on the display board that looked rough (even though it measured in the proper range). It has had u13 and u14 socketed in. It looked like one controlled one half of the segments and the other the other half based on the schematics. I switched them, thinking if that chip were bad it would cause another segment to go out. However still only missing segment p. I also measured the resistor in line with that chip and segment p. It measured correctly as well.

This is where my ability to trouble shoot has ended lol. I know the information for the alpha displays comes from the mpu. But I don’t know where. The mpu had some older acid but has been cleaned up and the game is functional. I’m just looking for some fresh ideas on where to go next. I want to get the game 100% functional before I shop it out. I appreciate any help

It’s out on all of the digits

I do not have a logic probe but I have one ordered that should be here in a couple of days. I will check that as soon as it gets here. Thanks

Ok so I’ve never used a logic probe. This is what I have so hopefully it will work. Anyone want to chime in and school me on how to use it please

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Ok so next dumb question. I go into display test and it just cycles trough the digits. How do I lock them on

Ok thanks. It will only lock one complete alpha digit at a time instead of the whole row but that should work right

Ok so I am assuming that pin is on the left? If so then it lit both high and low and constantly pulsed. Did I do that correctly lol

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I tested pins 9 and 10 on u17 and the result was the same as on src5

R4 reads 7.72k ohm

I will order that chip and report back as soon as they come in. I appreciate the help

Thanks. I will test it first before ordering.

I haven’t gotten to testing this yet. I’ve been swamped lately and it’s been cutting into my pin time. I will check it out shortly though.

I got new chips in. I replaced the u13 since it was socketed in. It instantly blew the fuse for the displays. I replaced the new chip wth the old chip and it blew the fuse again. Also now the game will not boot with ribbon cable attached to the display driver from the mpu.

There was some older alkaline damage as I mentioned in the first post. It had been previously cleaned and neutralized and the game is functional minus the missing P segment on the display.

I picked up an X-pin display so I’m probably just putting this board up for the time.

Yes the Xpin display looks super nice. Now if I can just finish up the mpu board... I’m ready to play it lol