This Metro Mini microcontroller-based clock is a minimalist timepiece that celebrates, rather than hides, its components. It's a straightforward build, electronically, and it's up to you to house and display it any way you like!

You can build it onto a breadboard, a perma-proto board, or even wire it dead-bug style without a board at all.

For this build you'll need:

1 x Metro Mini Microcontroller
Arduino-IDE compatible microcontroller!
1 x DS3231 breakout
Real Time Clock breakout board
1 x 4 Digit 7-segment Display
Clock display, pick any color!
1 x 5V USB Power supply
We stock or use one you have around the house
1 x Breadboard
A full-size breadboard will give you plenty of workspace


  • Perma Proto board, or
  • Female header pin strips, x2
  • Colored filter gel, tape

Let's have a look at building the electronics next.

This guide was first published on Jul 11, 2017. It was last updated on Mar 08, 2024.

This page (Overview) was last updated on Jul 02, 2017.

Text editor powered by tinymce.