Interrupt in Quadrature Encoders - help

Projects Programming
3

Your problem is in that attach statement, you don't put a pin number there you put a 0 if wired to pin 2 or 1 if wired to pin 3, those are the only two user interrupt options for a 328p based board.

So change:

attachInterrupt(CHA, checkDirection, RISING);

to

attachInterrupt(0, checkDirection, RISING);

Or assign the value of 0 to your CHA variable.

Lefty