wasp-os smartwatch firmware

What you’re building

wasp-os is a MicroPython-oriented smartwatch firmware for Nordic nRF52 devices, especially Pine64 PineTime. It supplies watch faces, heart-rate monitoring, step counting, alarms, timers, a stopwatch, calculator, games, utilities, and a Bluetooth-accessible MicroPython REPL. Its extended Adafruit nRF52 bootloader supports over-the-air development on sealed watches that lack a reset switch, exposed SWD, UART, or power switch. On a normal PineTime running InfiniTime, Gadgetbridge for Android can install both the wasp bootloader and main OS image without disassembly; source builds use Python tooling plus an Arm Cortex-M4 toolchain and can customize app selection through wasp.toml. The expected result is a hackable watch interface and REPL. The critical constraint is brick risk: the watch must be fully charged during bootloader updates, sealed devices should use official-release bootloaders rather than cutting-edge CI bootloaders, and early Y7S Developer Edition units require the separate DaFlasher path.

Key steps

1. Identify the PineTime generation: use Gadgetbridge for a normal InfiniTime device, but follow the documented DaFlasher route for an early unit that appears as Y7S.
2. Fully charge the watch and download an official wasp-os release, preferring its bootloader over a CI bootloader on any sealed device.
3. Copy reloader-mcuboot.zip to Android, pair Gadgetbridge with the visible InfiniTime device, and send the reloader archive through Android’s file browser.
4. After the watch reboots into the wasp bootloader/DFU flow, use the installation guide’s Gadgetbridge process to send the matching main OS image and wait for completion without interrupting power.
5. Wake the installed watch, connect with tools/wasptool --console for the MicroPython REPL, set the RTC, and verify watch face, battery meter, touch, steps, and heart-rate functions.