The sourcecode is downloadable here. For a ready-to-burn hex-file click here. (Please do check the source code for the right fuse settings.

Attention!
Due to an error some pins in the Elektor-schematic were scrambled. Please change the pin numbers of the AVR as such:

Original pin	Change to
16	8
17	9
14	6
15	7
18	16

Many thanks to M. Eder for catching this.