Bicycle enthusiasts love having few high tech gadgets installed on it. Usually there are speedometer, lights and other stuff that can be purchased around. In order to have full control and ability to add new features the only way is to start building your own bicycle computer. Great start can be so called ‘jazda’ bicycle computer. It is based on Atmega8 microcontroller with (seems) Nokia graphical LCD screen.
It is battery operated (3V) device with three buttons for selecting actions. It has plenty connectors for various sensors including mandatory wheel rotation sensor. With this sensor computer already is able to indicate speed and cadence (RPM). There are also a bunch of derivative parameters like distance max speed avg speed. Graphical LCD allows plotting some data like speed during time. Project seems to be in progress and more features are on the way.