Julian Hespenheide is an interaction designer based in Germany who submitted to Arduino blogpost a writing machine called émile. It’s an interactive installation created in collaboration with Irena Kukric, David Beermann, Jasna Dimitrovskais and using Baudot code - a binary 5-bit code, predecessor of ASCII and EBCDID – intended for telecommunication and electronic devices, representing the entire alphabet.

It runs on Arduino Uno and  translates the bauds (/?b??d/, unit symbol Bd) into moving objects that are being sent over physical tracks in order to illustrate  a simple computational process of 5-bit binary information transmission:

The machine was built in six days with four people. In our group we came to the conclusion, that not every process in a computer is really transparent and it already starts when you type a simple letter on a keyboard. To unwrap this “black box” of data transmission, we set our goal to build a small writing machine where you can literally see bits rolling around. After some research we got back to the beginnings of Telefax machines and data transmission using Baudot-code. We then quickly designed punchcards and mapped them to a slightly altered baudot code table and cut them with a laser cutter from 5mm plywood.
Whenever a marble hits a switch, a short timer goes off and waits for input on the other switches. If no other marbles are hitting those switches, we finally translate the switches that have been hit into the corresponding letter.

Take a look at the machine in action: