A smartwatch I've been building using an nrf5340 inside of a Casio W800H.
- ISP2053 as the microcontroller
- BMA400 accelerometer
- LIS2MDLTR magnetometer
- LS010B7DH04 memory-in-pixel display
- reuses the buzzer on the W800H backplate
- emulates a PineTime watch to use GadgetBridge
- music control via GadgetBridge
- weather via GadgetBridge
- Apple notifications coming soon!
- npm1100 battery charger
- lipo battery: 2 day battery life but I haven't optimized the firmware yet.
I started with the Nordic nrf5 SDK and then ported it over to ZephyrOS. I started with an nrf52840 (HJ-840) but the nrf5340 was too tempting.