LED Clock

This is a DIY LED clock I built. It has a slot for a Raspberry Pi Zero, which controls the LEDs.

There are 4 parts: a backplate (this is the largest part and should ideally fit on your build plate in one piece), and on the front side, one part for the Raspberry Pi, one inner ring, and one outer ring.

I used 8mm (radius) WS2812 LEDs, but you can use anything else that fits and that you can control with the RPi. The WS2812 LEDs have the advantage that they only require 3 wires for full RGB. I connected all the LEDs in the ring with two rails of +5V and GND, and then chained their Data in and Data outs together. Be aware that it's a lot of work to solder all 48 LEDs together at 4 pins each.

It uses a few M3 screws and hex nuts to keep the backside connected to the rings and the pi slot. There are also 2 holes for wall mount screws. The LEDs should fit snuggly into their holes, but some small amount of glue might be useful to keep them in.

I used my own implementation of controlling the LEDs using bit mashing on SPI pins, and since this is software, the colors sometimes (but relatively rarely) spasm a bit. A implementation/remodelling using a pico or other microcontroller would make sense.

The code I wrote and used can be found at https://gitlab.com/Rubydrag0n/led-clock. It shows the time like a normal analog clock, using the inner ring as the hour arm and the outer one as the minute arm. The color changes very slowly. The system time is used for display, so if the locale is set correctly and the pi has internet (Pi Zero W), it can automatically correct itself and change with DST.