The build relies on that old stalwart, the Arduino Uno, to run the show. It’s hooked up to a DS3231 real-time clock module so it can keep accurate time for long periods, as is befitting a clock.

It takes a handful of LED arrays with an integrated driver, an Arduino Nano, a real-time clock module, and a voltage regulator. The software uses a custom 6×9 font and handles addressing the LEDs ...