Arduino charlieplexing example (4 pins, 12 LEDs)
https://github.com/marcuserronius/ChuckPlex I couldn't get the original code to work- the pin numbers seemed to be corrupted (non-sensical at least) when writing outputs to pins, trying to set pin 24652 for example.
So I macerated the original Chuckplex library, and made the class a rather clumsily-hacked bit of code for controlling 12 LEDs with 4 pins. It has been made less generalised- no class (haha) and fairly 4-pin specific, though I hope to fix this eventually.
A wordy clock for my wife... My arduino nano does not have enough outputs for all LEDs independantly, so charlieplexing is the easy way out. And no- I do not want to use neopixel LEDs- I want to power it with a battery, not from the mains.
This displays the (zero-ordered) pin numbers supplying each node (LED). The original Chuckplex code does a good job of ordering the wiring by pins, rather than node (LED), and I borrowed the nice method of generating the wiring.