Why not just make a keypad that uses only one analog pin? I made a library just for those type of keypads and put it in the playground. Here is a link. OneWireKeypad
Just follow my diagram and look at my example sketches.
Why not just make a keypad that uses only one analog pin? I made a library just for those type of keypads and put it in the playground. Here is a link. OneWireKeypad
Just follow my diagram and look at my example sketches.