1/ So it might only be early November, but I've already got the Christmas tree up 🎄Why? Two reasons... the joy it brought to the tiny people in this house, and the fact I've had to wait almost 11 months to try out my homebrew individually addressable RGB tree lights!
Considering what it would cost me to buy these off the shelf, I managed to build them for ~£25 ($30 or so), and an evening of soldering & tinkering with WLED (https://github.com/Aircoookie/WLED)
2/ So for context, this was just after Christmas 2021, and I'd seen the likes of Twinkly (https://twinkly.com/) with their cool looking addressable RGB tree lights, but I didn't fancy forking out over £100.
So... I already knew about WS2812B and similar LEDs, and that you can buy long lengths of these from Aliexpress and similar, but a flat ribbon of these on a tree wouldn't look exactly _magical_.
So I took to Amazon (mostly for ease of being able to try and return lots of sets of lights)
4/ So the first this I did when the turned up was plug them in and check they worked as expected before removing this plastic casing on the USB and controller & desoldering the 3 wires for the string.
Next up, I took an ESP8266 (in this case a tiny D1 Mini) and quickly flashed it with the latest copy of WLED - github.com/Aircoookie/WLED
5/ This software is fantastic, and has meant I can build all sorts of fun LED lights for my kids bedrooms etc. You can see a quick demo here: https://www.youtube.com/watch?v=yMIoA_Xe4B8
Anyway, with the D1 flashed, I soldered on the string of lights, and crossed my fingers. It worked first time - that _never_ happens!
Proof of concept over, I ordered another set of lights (400 in total, over 40 meters), and tried to figure out a sensible way to wire this mess up.
6/ Because of voltage drop over that many LEDs, I have two segments of 20m (so kept the strings separate) to save having the re-inject power. There's a bit of drop
over the 20m, but not too bad at all if you don't have them too bright (which you don't...)
I 3D printed a little case to hold my D1 mini, with a 5.5mm barrel connecter that will power the ESP8266 and both strings.
7/ With that, I wrapped the strings around a couple of thin cardboard boxes I had so that they wouldn't get tangled, and they've sat in the drawer for almost 10 months...
And they worked perfectly first time! Next on the todo list however, as it's a plastic tree, is the see if I can leave the lights attached to save taking them on and off each year... I envisage some more soldering to make the strings separate with each segment of the tree...
Graham Stevens