I was in a thrift store recently and saw a game with a screen and a keyboard and I thought, that would make a good Enigma machine (I’ve always wanted one, but I know my wife would kill me if I bought a real one $$$). In this instructable I’ll show how I gutted an kids game and used an Arduino to hook up to the keypad and speaker. The code’s not too bad (so far). This version is a simple three rotor Enigma machine. You can switch the rotors around and change the letters for the rotors. Future plans are to all for more rotors, allow changing out the reflector, allow for spinning the ring around a rotor, and a plug board implementation. This Enigma machine will be able to encode and decode messages to and from the real, old Enigma machines used during Wold War II.
Arduino Enigma Machine