// the find
No-Chicken/OV-Watch
A powerful Smart Watch based on STM32, FreeRTOS, LVGL.
OV-Watch is a fully open hardware+software smartwatch built on STM32F411, FreeRTOS, and LVGL v8. It includes schematics, PCB Gerbers, 3D-printable case files, and a complete Keil firmware project with BLE OTA via a custom bootloader. Aimed at embedded developers who want a real-hardware LVGL/FreeRTOS reference project they can actually build.
The hardware is genuinely open — Gerbers, schematics, and STL files are all included, not just the firmware. The LVGL simulator setup for VSCode/Windows is a practical inclusion that lets you develop UI without touching hardware. The hardware abstraction layer (HWDataAccess.c toggled by HW_USE_HARDWARE) is a clean way to share code between simulator and device targets. The power design is thought through: three distinct power states (run/sleep/off), RTC-triggered wrist-raise detection instead of raw IMU interrupt, and measured sleep current around 800µA.
Blood oxygen (SpO2) is listed in the hardware with an EM7028 sensor but explicitly unimplemented in software — the README says so directly. The README is almost entirely in Chinese with a partial English translation, which will slow down anyone trying to understand the architecture. The heart rate algorithm ships as a precompiled .lib binary (HeartRatelib.lib, libBp.lib, libBpm.lib) with no source, so you can't debug or port it. Build tooling is locked to Keil MDK; there's no Makefile, CMake, or STM32CubeIDE project, which is a real barrier for anyone not already on Keil.