Writing "0" to this port supposedly switches it from Analog mode (ADCs) to Binary Input.
that made me curious, so I had a look.
Did not see the above, but it is clear from the following extract from the datasheet that you must write a '1' (after writing 0?) to get an input.

from the data sheet: "The alternate functions of P1.0, P1.1, P1.5, and Port 3 pins can be activated only if the corresponding bit latch in the P1 and P3 SFRs contains a 1. Otherwise, the port pin is stuck at 0."

However when I try to input the digital data all I get is rubbish
Since this does not state all zeroes, I believe that there must be some ADC enable/disable mechanism that is not (de)activated. What that is I'll leave to the original poster, I have had enough datasheet reading of a device I do not use.

Why would you connect digital output devices to Port 1 in ADuC812 while you have Port 0, 2 and 3 for digital stuff?
seems a very valid question.


Erik