Ms Pac VRAM addresser /Z-80 sync buss controller ?

SpartyMAC

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I was doing some board testing in my Ms Pac Cocktail and after all the testing was done I put my once working board back in and think that I had either the VRAM addresser or the Z-80 sync buss controller put in wrong. Well now after I corrected the orientation of those cards the game boots and goes to the start screen but as soon as I hit player 1 or 2 I hear a clicking and the game resets. If I just leave it alone it just sits on the attract screen but as soon as I try to start a game it resets. I have unplugged the coin door so its not the slam switch and I have check all the voltages and everything looks good. The fuse block has also been replaced.

So my question is did I fry one of those boards when I had them in wrong? And do the symptoms that I am showing coincide with a fried VRAM addresser or Z-80 sync buss controller? Any help would be appreciated. Thanks
 
Yes.

I'm surprised the game comes up at all. You could've fried any to all of the chips on either board if they were plugged in 180 degrees out.

If all you did was plug it in the right direction but just off a row of pins then nothing should've happened to it.

RJ
 
If it helps, when they were plugged in backwards, the board only had power to 1 of the 12v lines, both 7v and 1 12v fuse were blown. That could be why it comes up somewhat but wont start.
 
I was doing some board testing in my Ms Pac Cocktail and after all the testing was done I put my once working board back in and think that I had either the VRAM addresser or the Z-80 sync buss controller put in wrong. Well now after I corrected the orientation of those cards the game boots and goes to the start screen but as soon as I hit player 1 or 2 I hear a clicking and the game resets. If I just leave it alone it just sits on the attract screen but as soon as I try to start a game it resets. I have unplugged the coin door so its not the slam switch and I have check all the voltages and everything looks good. The fuse block has also been replaced.

So my question is did I fry one of those boards when I had them in wrong? And do the symptoms that I am showing coincide with a fried VRAM addresser or Z-80 sync buss controller? Any help would be appreciated. Thanks

Bring it by my place, I have extra VRAM addressers and bus controllers. We can test it out in my cab and get it working.
 
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