Multi-pattern, multi-speed LED chaser

摘要

This circuit is built around an AT-mega8 microcontroller (ICl) and 32 LEDs which form a cross, with eight LEDs in each branch. The easiest way to build it is with four 8-segment common cathode LED bar graph displays but you could use discrete LEDs. The cathode terminals of each group of eight LEDs are connected together and then through a 47Q current-limiting resistor to one of four pins on Port C of microcontroller ICl (PC2-PC5; pins 25-28).