Hi folks,
I have three Gameplan MPUs I'm working on, 2 have similar behavior and 1 won't even light the LED. Before I get too into it, let me say I have a fully functioning Sharp Shooter 2 that I'm testing these boards in.
1 MPU-2 rev 1 fully boots into attract mode, starts and plays a game but is not recognizing switch inputs on at least these switches:
Playfield candycane kick out hole
1000 point rollover switch on mid left side, just below 50k switch
Coin door switches
Credit/start game button
~I've replaced U18 and U23 and swapped in good chips in U17, I haven't removed and socketed U14 yet but that's next on my list.
1 MPU-2 rev 2 fully boots into attract mode, but that's it, won't start a game. Will not accept credits from coin switches but it's on freeplay anyway.
~I've replaced U18 and U23 and swapped in good chips in U17 and U14.
1 MPU-2 rev 1 as I said won't even light the LED or blink at all...
I do have a decent DMM and a logic probe but I'm a rookie with the logic probe... Any help with these would be greatly appreciated!