[TenTec] OMNI VI Model 563 -- no digital readout (Peter Bertini)

[Gregory Smith]

Hi Pete,

Thanks for your latest suggestions.  I verified the uP is running looking at the ALE (pin 30), running at approx. 3.24 Mhz.  Vcc is 5.3 Vdc.

Since all the front panel switches function, I assume the uP is running the logic ROM program.

This afternoon I just notice that the uP display clock and data outputs also go to the PLL board 81599 that has its own Vcc power supply. If there is an issue with that, it might cause chips U3 & U6 to load down the uP lines. I'm hoping that is the problem. I'm seeing pulses on the uP address and data lines.

Best,
Greg (W2GLS) Gregory Smith