Introduction: DIY Keypad to USB Keyboard That Beeps Random

About: Max Romagnoli is a programmer, developer, petrolhead, organizer, living in Italy since 1992.

I made this project just for fun, but this thing work as an normal keyboard with everything.

Have fun!


Step 1: Hardware


IMPORTANT! This project work only with this kind of Arduino, because it have an ATMEGA32U4, who can emulate the keyboard


A keypad is a simple matrix of rows and columns, if you have a 4x3 keypad you should have 7 wires to use.

I weld the wires directly to the arduino, from digital input "D3" to "D9".


This is a totaly optional component, but i love the "bip pob pub" sound.

Any computer buzzer work just fine, i weld one to analog input "A3" to "GND" (ground)

Step 2: Software

You can download the software from GitHub:

Upload "keypad-to-usb.ino" file to the Arduino using the Arduino Software

I made the "beep" sound totaly random, just for fun.