pins - Multiple buttons on single interrupt, how to debounce? - Arduino Stack Exchange
problem debouncing multiple buttons with interrupts - Programming Questions - Arduino Forum
sjcomeup.com - multiple buttons two pins arduino
Multiple Buttons on 1 analog pin - Exhibition - Arduino Forum
Playing with multiple buttons | C Programming for Arduino
Multiple Push Buttons on One Arduino Input - The DIY Life
GitHub - dxinteractive/AnalogMultiButton: Arduino library to capture multiple button presses through a single analog pin, as well as onPress and onRelease "events" and button press times.