Jazda is a bicycle computer based on AVR microcontrollers and mobile phone screens. The project covers both the software and hardware design, providing the source code and schematics.
Originally, it was built around AtTiny2313, now it's AtMega8. The microcontrollers were chosen because of their popularity and resistance to damage.
The other significant component is the screen. The project aims to be compatible with at least a few popular low-powered displays in the future, but at the moment only one is supported.

Project page:
https://github.com/rhn/jazda
Project wiki:
https://github.com/rhn/jazda/wiki/
Introduction, tutorial and hardware documents:
http://rhn.github.com/jazda/


FEATURES

5 speed measuring functions: current, max, average etc
Cadence measurement
Plotting as you ride
Low power consumption
DIY hardware
Modular code design


ASSEMBLY

For hardware needed to assemble the device, see docs/hardware
The schematics are available in Eagle format in eagle directory AND on the
project page (PNG format).
You will need an AVR programmer to upload the software to the chip!


SOFTWARE BUILDING

Linux:
To build & upload the software, you need:
- avr-gcc
- avr-libc
- avrdude
- Unix shell
1. Connect the AtMega8 chip to your computer using
your programmer (refer to the programmer's manual)
2. Consult avrdude manual to find your programmer's name (in this example, it's
"usbasp")
2. Issue the commands:
cd src
sh ../build.sh usbasp m8 main.c
replacing "usbasp" with your programmer's name


AUTHORS
rhn@porcupinefactory.org