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Thanks for hanging in there with me.
I checked the 3 EPROMs I have, to identify those which work in the OK DME and found that the one that was in the NOK DME during the short circuit is damaged.
Putting the known good EPROM in the NOK DME I still get the reset signal on pin 9 of the uC...
Jumpers to make the DME work with 256kB EPROM are identical in both DME's: B700, B701, B705, B706
To summarize:
-All IC's replaced apart from S703 ADC
-known working EPROM
-5V DC supply to the digital board after replacement of 5V regulator and track on analog PCB.
.All diodes tested ok
-All capacitors tested ok
-ALE signal of 8051 replacement correct at 1MHz
But 8051 replacement keeps resetting.
Where do I look next?
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