Logic probe pulsing CPU still alive ?

dyno

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So I thought I may have killed the Zues chip on my Exotica board . But when I check the input and out out on the PIC chip , I get pulsing on the output for a bit then it stops. The crystal oscillator is also pulsing at the time when the PIC is but stops when the PIC stops. Both my boards do this . I get nothing though on the eproms pulse wise .

Maybe I am grasping at straws and am in denial these boards are toast lol
 
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The PIC chip starts it all... If it's dead the board will appear dead. I ran into this repairing a couple of "The Grid" boards for an arcade in the midwest. One of them had a dead Security PIC.
 
I used my oscilloscope to check some pins on the CPU and it's showing some interesting readings , so that should mean the CPU isn't dead . Am I right on that? I don't get any pulsing though with my logic probe. I am new to the world of oscilloscopes .
 
Depends on the voltage levels. If they aren't going high enough they won't trigger the logic probe and may not trigger a logic high state.
 
So I noticed that on my Cruis'n exotica board the cpu clock in is dead .Unfortunately the schematics for this board are not available. Is this a RAM issue or if the Zeus chip is dead would this cause this problem ?
 
There are square silver crystal oscillators on that board. The faster ones won't read on a logic probe but will on an oscilloscope.
 
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