Hardware project · In progress

PomodoroPebble: a physical study timer

I built PomodoroPebble to make focused study sessions easier without keeping a phone or laptop timer open. It combines custom electronics, embedded firmware, and a compact enclosure designed around the way the timer is used.

CAD render of PomodoroPebble, a pebble-shaped timer with mechanical switches and an OLED display — CAD render of the custom enclosure, OLED display, and mechanical controls.

Why I made it

Online timers are convenient, but using a phone or laptop during a study session can introduce distractions. PomodoroPebble is a dedicated physical alternative: start and control a focus session with tactile switches, then check the remaining time on its small display.

Design and build

The device uses a Seeed XIAO RP2040 microcontroller and a custom PCB. Two MX-style mechanical switches provide physical controls, a 0.91-inch I2C OLED displays the timer, and four SK6812 MINI-E addressable LEDs provide visual feedback. The enclosure is a 3D-printed pebble-shaped shell that fits together with magnets.

Exploded CAD assembly showing the PomodoroPebble enclosure components

Custom PCB layout designed for the PomodoroPebble timer

Current status

PomodoroPebble is in progress. The project brings together CAD modeling, PCB design, firmware, and iterative hardware prototyping. I’ll update this page as the build develops.