Another development that might be telling - I just connected and the diagnostics very quicky upon boot, and it shows the errant measured supply voltage and VCC by by the processor ramp up in voltage over the course of several seconds. It starts out as good, and then voltage creeps up. Is this suggesting a processor issue? I instrumented the "ADC_BATT" line and it holds steady at about 1.7V which is what I calculated as expected value for a 10V supply.
