Well, a couple more hours of debugging has made the basics of my Atari 2600 project work. Have I mentioned what it is yet? No? Well, it’s an implementation of the German World War II three rotor crypto machine commonly known as the Enigma. I wrote a simulator of the machine in C a few years ago as part of my attempt to crack the ciphers in Simon Singh’s Crypto Challenge as part of his book The Code Book. As of today, there still is some work to be done, but my 2600 version works, deciphering messages that are encoded with my C implementation.