Thanks for the reply,
I've already checked the 8085 clock out ( 3Mhz ) and Res7.5 signal ( 3000hz )
and replaced the eeprom testing both firmwares posted in the files section.
Still no go...
However, another clue is the lack of signals at the A,B,C ports of the 8155 IC
while still getting the desired Timer out ( 500Khz ) signal when the eeprom is installed.
What is the best strategy for testing the DTC's and the 6116 ?