using a adafruit feather M0 with SPI oled SSD1331 (16bit) and MPU-6050 as watch and step counter.
sometimes I got a restart and time accurency is bad :-S
- feather M0 with BLE module nRF52 (set clock and send small messages via UART)
- OLED 16bit color SPI display (clock, powerbar, with dim mode and off mode)
- MPU6050 i2c gyroscope chip (shake to switch display on and steps counting)
- small ear speaker (beep on button press)
- 3 buttons: set hours, minutes, display on and show details (long press)
- 25k poti to change the clock color
- 3,7V 180mAh lipo (>10h)
I use the watchdog timer https://github.com/adafruit/Adafruit_SleepyDog to sleep
and NOT delay() to save power!
shake or press button
it is a black display and save power :-D
