Hi Mischl,

I'll save the more experienced people the reply.

1. What MCU are you using?
2. Does it have an analog port?
3. Did you disable the analog port and make it digital?
4. Did you disable the comparators if they're on your MCU?
5. Did you read the MCU data sheet?

There are enough posts on this forum to answer your questions and also give you the answers to the above.

Excuse me if this sounds like a smart ass but usually anything out of the ordinary happening with port A can be blamed on not changing the port to digital and disabling the analog feature and the comparators.

BobK.