Waza_be:
Thank a lot!Googling " 'floating input pin'" and wikipedia gives me really a lot of great information.
I guess I need to learn how to activate the internal pull up resistor, because I don't want to add resistors on every input!
Will read a lot, thanks for the hint
Well I would ask why would you want to read a pin that has nothing wired to it in your sketch? Floating input pins are not a problem if you are not using those pins for anything useful.
Lefty