I got this idea by browsing the web. I found by hazard Mr. Bob Blick’s page who make the first propeller clock. I began to check how can I build one myself. Base on AVR AT90S2313 I saw rapidly that my MCU must be clocked very fast to make all the calculations needed to light the leds at the right place. The speed is at 16Mhz, 4 times faster than Atmel’s specifications. It’s working without any problems.
Propeller Clock – [Link]