I have used the ADuC812 and programmed it using the Serial downloader WSD.
The programmed IC now refuses to enter download mode. When reset or power cycled it always RUNS the original program.
I have checked that PSEN is shorted to ground and EA is pulled up through a 10K resistor. Voltages checked at the IC pins.
I have also checked that other pins are not unduly connected or disconnected. All power supply and GND pins are also checked.
Before I decide to discard the IC or board and replace it, I would like to find out if any other explanation can be suggested by the forum members