Instructables

How can I matrix RGB LEDs to the Arduino Duemilanove?

I just picked up the Arduino Duemilanove and want to make an LED matrix of RGB LEDs, however I don't know which LED s I should buy, or how to control each LEDs color. I understand charliplexing and turning an LED on or off, but not RGB. Does anyone have any instructable like this or any other resources?

Use the Allegro A6282 chip to do all the hardwork for you. Make a single colour driver, and then either multiplex it to the other colours, or make three driver sections.
frollard4 years ago
RGB is easy like single leds - it just has 3 leds in one.

Trouble with running rgb on the arduino is it only has ~15 io pins, and non-matrixed rgb leds take 3 pins each.  Matrix them and you can fit 15/(w+h)/3...

To increase the IO pins you can use simple 595 shift registers, which use a data pin and a clock pin to output to 8, 16, or any other multiple of 8 pins...at a cost of speed.  

Other options include led driver shift registers (maxim makes a chip that does this) but they get more expensive as you get more technical.

I would highly recommend making a matrix of 1 colour of led first to figure out how it works - then add more and more.