No buttons.
Just flip it.
Pomodoro Gravity Cube reads its own orientation with an accelerometer โ flip it to a different face, get a different countdown. No app, no touchscreen, no notification competing for your attention.
Try it in your browser.
The exact firmware, running against a virtual MPU6050. Click the switch to power on, then drag the sensor's X/Y/Z axes and watch the OLED and LED react in real time.
No install, no account, no cube required.
One light. Five signals.
Face 1โ4 pointing up
Timer active
Solid green. 5, 15, 25, or 45 minutes, depending on which face is up.
30 seconds remaining
Warning
Blinking yellow โ time to wrap up your last thought.
Countdown reaches 00:00
Time's up
Blinking red. Flip to any face to reset and start again.
Screen face pointing up
Paused
Solid blue. Flip back to the same face to resume exactly where you left off.
No face detected yet
Idle
Off. Sitting flat, waiting.
What's actually inside.
Firmware libraries:
A few deliberate choices.
No buttons, on purpose
Orientation is instantly learnable โ no documentation, no menu. Flipping the cube to start a session is a small physical ritual that reinforces the intent to focus.
millis(), not delay()
A blocking delay() would freeze the device mid-countdown, deaf to orientation changes. Tracking elapsed time by hand keeps the accelerometer polled every loop.
The 7.0 threshold is empirical
Tuned by testing on this specific enclosure, so incidental tilts while moving the cube across a desk don't accidentally switch timers. Different enclosure or mount? Expect to retune it.
Build your own.
Clone the repository
git clone https://github.com/mirconegri/PomodoroGravityCube.git
Install the libraries
Via the Arduino Library Manager: Adafruit MPU6050, Adafruit Unified Sensor, Adafruit GFX Library, Adafruit SSD1306.
Wire it up
MPU6050 and SSD1306 on the I2C bus (SDA/SCL). RGB LED on three PWM pins through 330ฮฉ resistors. Diagrams are in assets/.
Upload
Open src/cubo_pomodoro.ino in the Arduino IDE, select your board and port, and upload.
Built in the open, and in wood.
Look at the firmware, try the simulation, or build your own enclosure.