The World War II German Enigma encoding machine is something of an icon in engineering circles not just for its mechanical ingenuity but for the work of the wartime staff at Bletchley Park in decoding its messages. Without it we would not have had Colossus, the first programmable digital electronic computer, and subsequent technological developments might have taken a slower pace towards what we take for granted today.
Sadly for the Enigma enthusiast though, real machines are now few and far between. Our grandparents’ generation saw to that through the chaos and bombing of the fight across Europe. If you want to handle one you will have to either have an outrageous amount of money, work for a museum, or maybe for the GCHQ archivist.
This has not stopped our community building Enigma replicas, and the latest one to come to our attention here at Hackaday shows some promise. [lpaseen]’s meinEnigma is an electronic Enigma driven by an Arduino Nano, with rotary encoders to represent the Enigma rotors and multi-segment alphanumeric displays standing in for the lighted letters in the original. It supports all the different variations of rotors from the original in software, has a physical plugboard, and a serial port over USB through which all machine functions can be controlled. The machine as it stands is a fully working prototype, the plan is that a final machine will resemble the original as closely as possible.
All the code used in the project can be found on GitHub, along with [lpaseen]’s Arduino library for the Holtek HT16K33 keyboard/display chip used to handle those tasks.
We’ve featured a few Enigma machines on Hackaday over the years. One was built into a wristwatch, another into a hacked child’s toy, but the closest in aim to [lpaseen]’s offering is this rather attractive replica also driven by an Arduino. It is also worth mentioning that should your travels ever take you to Buckinghamshire you can visit the Bletchley Park Museum and neighboring National Museum of Computing, to get the Enigma and Colossus story from the source.