Re[2]: black widow pcb problem no play no picture clock working

stop doing things till i check the schematics ;-)

here is how it works (any game).

the clock allways runs - so does yours, so that's a good start.

the reset signal should start high and then pulse low for a second,
or simply start low and then go high.

if the cpu cant or wont run the reset should then start to pulse because of the watchdog.

so the place to be looking is at the reset circuit and the asociated watchdog circuit.

once the reset is acting right, then you can look at the address and data buffers or the cpu.

have you got a spare 6502a for test?

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Received on Sat Aug 6 22:19:38 2005