If i understand right - i connect pin 1 to my signal source (sensor output) with resistor on serial, pin 2 to ground.
Pin 3 connected to ATMEGA pin and this pin configured with pull - up enable and pin 4 connect to ground. Right?
So in this case - signal was inverted! If i have "1" on sensor side - i have "0" on input side...
i try - may be it work... If not - i reply here...
