Linux for iPod: Cracked thanks to the click wheel

The act of switching the OS on a beloved piece of hardware from a proprietary system to Linux doesn't make too many waves in the tech world any more - unless the hardware in question is an iPod and the canny coder in question had worked out how to make the change using the noises from the click wheel.

When German teen Nils Schneider, 17, decided to put the open source OS on his iPod he found the whole process too tricky with the latest generation iPod he'd received as a Christmas present, New Scientist reports.

Schneider set about trying to crack the inaccessible bootloader code with help from Bernard Leach, who works with Schneider on the 'Linux on iPod' project, which creates open source programs for the music player.

Leach had already cracked the code of the component which controls the wheel's clicking sound. In order to work out how the bootloader code worked, Schneider played it as sound through the click wheel.

The clicks were recorded and converted back into code. Some 20 hours and one sound-proof box later, the puzzle was solved and the iPod was capable of running new games as well as a Linux OS.

Leach told the New Scientist: "It changes from a consumer device, where the manufacturer sets the rules about what it will and won't do, into a general purpose device. Much of the interest has been to develop various games but things like a simple calculator, drawing program and even a GPS mapping interface are all possible."

The Linux on iPod project is now working on developing Linux programs onto the fourth generation iPod, iPod mini and iPod photo. The project has already developed Linux for the first, second and third generation of the iPod.