fungus:
Get a TLC5940 LED controller chip and use the basic example program (which just happens to be a "Larson Scanner" - which is what they're called).The chip makes sure all your LEDs are running at optimal power and protects your Arduino from the stress of charlieplexing.
I will look into one of the chips! I also want to learn how to do it with just the LEDs for practice too.
fungus:
Hippynerd:
Charlieplexing is a great way to control a lot of LEDs, but using LEDs with built in resistors might be an issue, since you will be always using 2 resitors anytime you try to light an LED.Not if the resistors are in parallel - which they will be if they're "built in".
Do you suggest i try something else then?