You may find additional programs for the Nokia N770 and N8xx series at my garage side at


A small software drumcomputer for the STM32 primer 2

Drummer is a small drum-computer application for the STM32 Primer2. The Primer2 is based on a ARM-Cortex3 cpu with 512 KB flash rom and 64 KB Ram. It is able to run at a speed of 72 MHz and has a 160x128 pixel color TFT, MEMS and 16 bit/44.1 kHz stereo DAC included. The drummer application was written for the 2009 Application Design Contest and won the fourth price.
For download look here at the project side at


A tool to play Ogg music files on the Sharp Zaurus

I wrote this tool in the years 2003-2009 to hear audio books and music encoded in Ogg Vorbis format. Sharp's music player wasn't able to skip forward and backward with Ogg files. OpiePlayer could not handle Ogg files with 22 KHz sampling rate and/or mono files (I can't remember). I encode audio books in 16-20 kbit/s mono with 22 kHz sampling rate. This sounds o.k. with Ogg Vorbis, but really bad with MP3. It still misses some features like a real playlist and MP3 decoding (does anyone really needs this?).
Yous OggPLay 1.0 for the Zaurus 5500 and OggPlay 1.2 for all VGA models. For more info, please see README. Features:

  • Keys are fully configurable.
  • Possibility to turn LCD on/off with a single key stroke.
  • Scans ogg files recursivly in the home directory /home/zaurus and on CF and SD cards (if plugged in).
  • Ogg Vorbis decoder library is included!
Licence: GNU Public Licence; OggPlay is (c) 2003-2009 by Klaus Rotter



A tool to create printed circuit boards (PCBs) on the Commodore Amiga

A PCB layout program I wrote for the Amiga in the years 1988-92. Never completly finished, although quite useful. Binary and source is included, you need Matt Dillons DICE system to compile it. GUI created with the old GadToolsBox programm by Jan van den Baard. It also runs inside the UAE Amiga Emulator.

Licence: GNU Public Licence Version 2, (c) 1988-1994 by Klaus Rotter
Download: (Amiga binary and source in ANSI-C)

Bomberman clone

for the Sharp Zaurus and Nokia 770 and 8xx

To download (Nokia 770 IT2006 Edition, hildonized with launcher), please go to the bomberman project at Attention: It is still beta and there may be problems with the network gameplay. Don't forget to turn on WLAN for network gameplay. Singleplay against computer should do nicely now! Please test it and send feedback!

Download (Old Nokia 770 IT2005 Edition, not hildonized!): bomberman_0.8-1.deb

Back in the eighties there was a great game called DynaBlasters on the Amiga, which was a clone of the famous Bomberman game. This is a port of Robert Hockaufs Bomberman clone to the Sharp Zaurus. The Java version ran quite slow, so I ported the C-version and rewrote the Java-AI routines to C. You need these SDL libs for the Sharp Zaurus 5500.
Gameplay: Move around with the cursor keys, drop bombs with the center key. To exit press the Mail key. Note: I have only tested this on my Zaurus 5500 with a modified Sharp ROM. There may be some problems with other SDL-Libs and/or the VGA-models (7xx, 8xx, ...)

Update V0.81 - hopefully this runs better on C7xx, C8xx, ...
Licence: GNU Public Licence Version 2
Download (Zaurus): bomberman_0.81_arm.ipk, source in C

ePaint - A small paint program for the eBookMan

The eBookMan is a PDA created by Franklin. I bought a eBookMan 900 sometime in the year 2002 and wrote this little painting program. It is able to write text, does freehand drawing, has variable pen sizes, draws (filled) rectangles and circles, has undo and saves and loads BPM images. To compile it, you have to download Cygwin and the eBookMan SDK. For more information look here. Note: It seems that Franklin does no longer offer the EBookMan SDK.
In 2004 Franklin dropped the eBookMan and I sold mine. So do not expect any further development. The source may be interresting for its graphic primitives (line, circle, fill) because the ebm's OS has not such functions.

Licence: GNU Public Licence 1
Download: epaint.seb and the source in C++

Interface for the Casio CFX9x50 calculator series

The CFX 9x50 calculators are often used in Bavaria secondary schools. This is a interface to connect these calculators with a PC using the serial port and the program FA 123. I've created the files using the free PCB program Eagle light.

Licence: Freeware, but no warranty at all!

Some shell-tools

This is a collection of some very small tools I wrote for the Amiga and later for my Linux boxes. I keep them here to not lose them.

Licence: Public Domain (to small to keep really a copyright on it)
Download: collection.tgz (source only, mostly in ANSI-C)
Hint: I like source code formated in the following way: indent -bli4 -bl -i4 -cli4 -npsl -l100