I have a flow meter that asks for a 3k-30k pullup resistor.
INPUT: 5-24 VDC @ 8 mA OUTPUT: NPN Sinking Open Collector @ 20 mA, Max.
It would be much easier to use INPUT_PULLUP on the signal pin then it would to make a circuit with a resistor in it...assuming that is safe to use.
Has anyone ever used INPUT_PULLUP as a pullup resistor for a similar connection? Also, does anyone know the value of said pullup resistor for each pin? I'm using an Arduino Mega and it says the pullup resistor can have a value of 20k-50k. I can't find any data that says which pins have which value for their pullup resistor.