![](/media/cache/profiles/ca55e81c481f3ae701c4362514ce6abd.50x50_q85.jpg)
Tests forked Keypad library.
Dependencies: FPointer keypad mbed
Schematic:
No extra hardware is needed besides the wires and switches. The columns are outputs configured with open drain. The rows are inputs configured with pull up resistors. A key press pulls down its row. With scanning the column is determined thereafter.
See keypad for the forked library used in this project.