Building an Arduino-powered Enigma machine

An Enigma machine refers to a family of related electro-mechanical rotor cipher machines used in the twentieth century for enciphering and deciphering secret messages. The original Enigma was invented by the German engineer Arthur Scherbius at the end of World War I. According to Wikipedia, early models were used commercially from the early 1920s, although they were later adopted by a number of militaries and governments around the world.

Recently, the ST-Geotronics crew designed and built a functioning open-source Enigma (M4) replica powered by an Atmel-based Arduino Mega (ATmega1280).

“Rather than try to immediately cram everything into the final enclosure, the ST-Geotronics gang painstakingly worked out a prototype to be sure the four 16-segment LED displays had been wired correctly and functioned properly,” explained HackADay’s John Marsh.

“The next step was laying out a swarm of buttons and resistors on a 6″x8″ perfboard. They used charlieplexing to handle the 16-segment displays (which actually have 17 LEDs each), and deceptively disguised each display as a nixie tube by mounting them vertically and encasing them in a transparent dome.”

Aside from the Atmel-powered Arduino Mega, key project components include:

• 26 Alpha Buttons
• 26 1/4″ Jacks Mono
• 10 1/4″ Plugs Mono
• 36 Pushbuttons
• 1 On/Off/On Switch
• 4 16Segment Orange
• 4 Test Tubes
• 1 Case Plywood
• 1 Hinge & Hooks
• 1 Half-Mortise Lock
• 1 Perfboard
• 38 Resistors 470 Ohms
• 40 Resistors 1K Ohms
• 7IRF9Z24N P-Channel MOSFET1 Piece of Metal & Spray paint
• Battery Case
• Rechargeable Batteries
• Battery Charger/Connectors

Interested in learning more? You can check out the hardware side of things on Instructables, along with the relevant Arduino sketches.