Pin should have flipped to LO for a split second on boot and stayed on HI for an enabled CPU. The next thing to check was the RESET pin on the CPU which should have been HI, but it was LO and stayed LO, which mean’t no watchdog system was barking. I started by looking at the clock circuit, I did this by checking the 68000 CPU’s Clock (CLK) pin which was pulsing as I expected, so the clock circuit must be good. PCB will not run at all, all I get on the screen is static garbage which is always the same whenever I try to boot. Which version you have is easily identified by a daughterboard (YM2203) on the underside of the PCB. It is an original PCB and is the YM2203 version unfortunately, much prefer the YM3526 version with superior soundtrack. Another on my pile that has been wanting attention for a while.
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