AVR 7-segment clock

This is my first small project I made with an AVR-controller.
The clocks heartbeat is a jitterfree, clock accurate frequency divider. Unfortunatly I've choosen a resonator as clock source, so that the clock runs to fast. After ajusting the divider value the error of about 1 second a day was acceptable.
The circuit can be viewed in every electronic book. Some 7-segments and LED's arranged as a matrix in rows and colums and a multiplex routine written in assembler. The two buttons are for setting the time.


front view of the hole raster board front view of the hole raster board

schematic (drawn with gschem)

schematic of the clock

download (asm-sources and schematic)

The license is public domain, so do whatever you want. This package comes with no warranty.
Source-Code and schematic: avrclock.tar.gz

download (C-source and part values)

I have some C-source code for the clock, too: clockc.tar.gz
And sometimes I get questions about the part values of the clock. Here's a schematic with values in it: avrclock.pdf

Have you build a clock based on that page? Let me know, I'd like to see a picture.
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created with quanta 3.1, werner.ho(AT)gmx.de 2005-07-02