photo CC BY-SA 2.5, GFDL or CC-BY-SA-3.0, Erato at Italian Wikinews, via Wikimedia Commons

I know many people who get value from a simple tool called the Pomodoro Technique.

It's a time management technique used to break work into periods of activity separated by short breaks. Each activity period is called a pomodoro. Why "pomodoro"? The technique was developed by Francesco Cirillo, who named the technique "pomodoro" as a nod to the tomato kitchen timer he initially used.

The technique has come a long way from those humble beginnings with phone apps, web versions, etc. I decided to make a simple hardware version in CircuitPython with a rotary encoder to set the time and mode!


Here's what you'll need from Adafruit to build the Pomodoro Timer:

1 x Adafruit ItsyBitsy M0 Express - for CircuitPython and Arduino IDE
What's smaller than a Feather but larger than a Trinket? It's an Adafruit ItsyBitsy M0 Express!
1 x NeoPixel Ring - 16 x 5050 RGB LED with Integrated Drivers
Round and round and round they go! 16 ultra bright smart LED NeoPixels are arranged in a circle with 1.75" (44.5mm) outer diameter.
1 x Piezo Buzzer
Piezo buzzers are used for making beeps, tones and alerts. This one is petite but loud!
1 x Rotary Encoder + Extras
This rotary encoder is the best of the best, its a high quality 24-pulse encoder, with detents and a nice feel.
1 x LiIon/LiPoly Backpack
Adafruit LiIon/LiPoly Backpack Add-On for Pro Trinket/ItsyBitsy
1 x Breadboard-friendly SPDT Slide Switch
These nice switches are perfect for use with breadboard and perfboard projects.
1 x Lithium Ion Polymer Battery - 3.7v 500mAh
Lithium ion polymer (also known as 'lipo' or 'lipoly') batteries are thin, light and powerful. This battery has a capacity of 500mAh for a total of about 1.9 Wh.
1 x Silicone Cover Stranded-Core Wire - 50ft 30AWG Blue
Silicone-sheathing wire is super-flexible and soft, and its also strong! Available in various colors.

Materials and Supplies

  • 3D Printer and Filament
  • Superglue
  • Small diameter heatshrink tubing


  • Wire Strippers
  • Wire Cutters
  • Pliers
  • Pin-vise drill and 0.8mm drill bit
  • Soldering Iron
  • Solder

This guide was first published on Jul 02, 2018. It was last updated on Jul 24, 2024.

This page (Overview) was last updated on Mar 08, 2024.

Text editor powered by tinymce.