We were scouring the world wide wibble and we found a Wisconsin bloke who has built a machine which can perform Alan Turing’s 1936 thought experiment on computable numbers.
In the paper Turing describes a machine that has an infinitely long tape upon which it writes, reads and alters symbols. He further shows that a machine with the correct minimal set of operations can calculate anything that is computable, no matter the complexity.
He said his goal was to create a machine that embodied the classic look and feel of the machine presented in Turing’s paper. He used a Parallax Propeller microcontroller, and running is based only on a set of state transformations loaded from an SD card and what is written to and read from the tape.
The symbols on the tape are manipulated by simple rules. He said that the heart of the Turing machine was the read-write head. This transports the tape and positions cells of the tape appropriately.
The head can read a cell determining what, if any, symbol is written there. The machine works on, and knows about, only one cell at a time.
The characters, ones and zeros, are written by the machine with a black dry erase marker.