Controlling the NeoPixel ring's individual LEDs from the GEMMA is quite simple. Since the NeoPixels are individually addressable, the only connections needed between the ring and the GEMMA are for voltage, ground, and control signal. That's just three wires!
Cut three short lengths of wire (enamel covered motor wire is used here, but you can use any type that you have handy). Strip a bit off their ends, then solder these connections:
- GEMMA GND -> NeoPixel Gnd
- GEMMA Vout -> NeoPixel Vcc
- GEMMA D0 -> NeoPixel IN
Once sodering is completed, bend and tuck the wiring so that the GEMMA fits neatly inside the NeoPixel ring.