A simple festive badge building on my previous LED wearables (e.g. the Social Battery and Christmas-themed badges). This version uses an ATtiny13A driving 12 LEDs via charlieplexing, arranged in a small tree-shaped PCB with minimal component count. A single button cycles through the lighting modes (steady, sparkle, fade and chase). It runs from a CR2032 and includes an optional ribbon loop so it can be worn or used as a small ornament. I had fun with this one, it was a bit of a challenge working out how to design the lighting patterns in a way that was easy to understand and get them to fit in the limited memory available. I ended up making lookup tables which set each LEDs brightness frame by frame. I limited myself to three brightness levels and used bit packing to compress the storage space required down. In the end it's a really nice effect!