We love IoT gadgets, but are occasionally concerned that they might allow access to the wrong kind of hacker. In this case, [Kevin] has created an IoT tree that allows anyone to control the pattern of lights, and he’s invited you to do so!
We played with the tree a bit, and the web interface is fairly powerful. For each LED, you can select either a random color or a keyframe-defined pattern. For the keyframe LEDs, you can create a number of “keyframes”, each of which is defined by a color and a transition, which can be either linear, quarter sine wave, or instantaneous (“wall”). Additional keyframes can be added for each LED, and if don’t specify a pattern for all the LEDs, the system repeats those you have defined to fill the entire string. There are also a few preset patterns you can choose if you prefer. If you, too, want to play with the tree, don’t delay: it’s only available through the first week of 2019!
Behind the scenes, an aging Raspberry Pi provides the local brains driving the LED controller and streaming the video, while a cloud server running a Redis instance allows communication with the web. The interface to the string of WS2811 LEDs uses [Kevin]’s Kinetis LK26 breakout board, which he managed to get working despite the state of tools and documentation for the Kinetis ARM family. You can read a good discussion of the system on his blog; there are a surprisingly large number of pieces that need to work together. As usual, he provides all the source code for this project on GitHub.
But, if it’s IoT Christmas trees that have got you thinking, you can check out this one from last year.