mauried:
The parallel resistor is in the AVR, you cant switch it out.
You dont need an external parallel resistor.
Ah, you said "AVR" and I read "Arduino". My fault. The Arduino UNO R3 has an additional external parallel 1M resistor, that is the one I was talking about. It appears to be unnecessary in most circumstances, but doesn't cause any side-effects so appears to be a good design choice.
