RGB LED Cube Driven by an ESP8266
Joshua Bird's cube was designed around 96 individually addressable LEDs and three boards.
LED cubes are an excellent addition to any desk or coffee table, and while you can buy them directly, some prefer to build their own. Joshua Bird chose the latter with one of his own featuring 96 RGB LEDs.
"The LED cube is a made out of six sides of 16 LEDs for a total of 96 individually addressable RGB LEDs," Bird notes. "The cube's sides are about 35mm, which really doesn't leave much space to put all the electronics."
The cube was designed using three boards, including the mainboard outfitted with an ESP8266 microcontroller and an ADXL345 accelerometer, a popular chip among Arduino enthusiasts. The cube also packs a USB board equipped with a Type-C connection and a TTL (CH340) chip with a programming circuit, making it easy to code the ESP8266 without needing to press a button. Plus, the Type-C port is almost universal, so it can easily connect to Mac or Windows devices.
Last is the power board, which has a battery charging circuit (TP4056), on/off switch, low dropout regulator, and a logic reset circuit. Power is provided by a tiny 400mAh LiPo and switches over to USB when a cable is plugged into the board. The cube makes use of WS2812B-Mini RGB LEDs, and while they are rated for 3.7 V, Bird has gone as low as 3.3 V without any issue.
With everything soldered into place, Bird then programmed the RGB LED Cube using C++, which was introduced via the Arduino uploader. The locations of the LEDs in a 3D space are stored within his code, which allows Bird to make animations that change depending on the cube's orientation. A complete walkthrough of the RGB LED cube can be found in Bird's blog post.