The Arduino uses a shift register to interact with the keyboard’s 8×10 matrix, and the sketch translates any serial data it receives into the keypresses the clone is expecting.

Watch the video below to learn more about his Arduino-based portable keypad that connects to your Arduino development board and offers the complete alphabet, numbers 0-9 as well as several commands.

He programs the Arduino bootloader into the chip, and then he’s using the Arduino Leonardo keyboard libraries. Bam! Check out the video below.