Earthshaker
Williams, 1989You're currently viewing posts by Pinsider ravve.
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Troubleshooting the display on Earthshaker and found out that SRC4 and SRC5 on the CPU board are acting strange.
They are measuring fine (4.7K ohm) only when the U41 and U42 PIAs (6821) are removed from the board.
When putting the PIAs in place, the resistance on SRC4 and SRC5 drops to about 2.45K ohm.
All this is with board on table (no power).
What could be causing this, should I assume that one of the PIA is bad? Perhaps it is normal behaviour?
Quoted from G-P-E:Yes, they can affect "measured" resistance but not real resistance.
Thanks, so is this a sign of bad PIAs or is it expected behavior?
Quoted from PinballManiac40:Expected behavior on some of the SRC parts. What issue are you having with the game?
Issue is that game is working, but display only showing something like "E,E," on the bottom screen. Verified all voltages are correct.
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Fort Wayne, IN