Here is a simple, yet useful circuit of an Arduino 4-digit 7-segment LED display unit. The module used here is a self-contained, compact common-cathode module containing four 7-segment LED numeric ...

He embarked on creating another large seven-segment clock to put inside that enclosure. Clocks, and specifically seven-segment based ones, aren’t anything new to write about.

Digits transition by having segments slide vertically in a smooth animated motion. It’s an attractive effect, and the code is available on his github repository for anyone who wants to try it out.