Simple to use library to interface matrix keypads.
Features: blocking or non-blocking read; supports any number of rows and columns; user defined key mapping; prevents reading the same event twice. Limitations: don't handle multiples keypress simultaneously; saves only the last key pressed.
Maintainer: Victor Salvi
This library is compatible with all architectures so you should be able to use it on all the Arduino boards.
To use this library, open the Library Manager in the Arduino IDE and install it from there.