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.

Last updated on Jul 11, 2017 Published on Jul 11, 2017