The hardware identified so far is the following:
- nRF52832 chip
- Color Memory LCD (panel by JDI, most likely) with backlight, using ST7301 controller
- One touch button (handled by 233DH IC)
- Vibration motor
- BMA253 tri-axis accelerometer
- Heart-rate sensor (EM7028)
- SPI FLASH "font chip" (comes with preloaded fonts) GT24L24A2Y
Currently I'm working on running the watch firmware on a MakerDiary nRF52832 board, before flashing the watch (to reduce chance of bricking it). I've already introduced some modifications to bootloader used to load up Espruino to reduce chance of bricking and manage to build a minimal NuttX image that successfully flashes via OTA and initiates a watchdog at the very beginning. Next step is to start supporting the sensors and display. I will probably support a very minimal "watch" app first but then start adding features. The idea will be to offer NuttX console over BLE UART as well as provide the possibility to transfer apps to NuttX over BLE directly instead of going through OTA process. Once everything is ready and tested, flashing a stock DK08 could be very simple.
I'll keep this project update from time to time and to store resources (such as datasheets) and provide links to appropriate repos. As this is a side project of a side project, you may find updates more often on my twitter account.