A Little Rest-Interval Timer

Using CircuitPython on a Particle Argon (or any CP Feather really)

Inspiration

This project was born from two desires. One, I'm sick of having to pull out my phone to operate workout timers. They technically work, but reaching for my phone means looking at my phone, and looking at my phone means thirty seconds of rest becomes a four-minute scroll through who-knows-what. I wanted a single-purpose gadget had one button so I could always use it correctly even when exhausted.

Two, I had a Particle Argon (an nRF52840 board) gathering dust ever since I got it on a massive sale. It came with a breakout board and a bunch of hardware add-ons that could be connected quickly with Grove connector cables, so I figured I'd see if CircuitPython could give it a second life as something gloriously, defiantly offline.

Spoiler: it can, and the result is perhaps one of the least connected IoT devices I've ever built. Which, after the gym-phone problem above, is exactly the point. ;-)