STM8S103F3P6, 8KB Flash, 1KB RAM, 16 Mhz STM8 core MCU
STM8S103F3P6 based design. STM8S103F3 is normally used for development then you can switch to STM8S003F3 which is lower in cost in production with same pinout and features.
What you need to develop
The microUSB port on board is for Powering the board only from USB. No other purpose.