schematics for discovery board
The stm8 discovery board can be programmed using the Arduino IDE after board preferences have been modified.
http://arduino.esp8266.com/stable/package_esp8266com_index.json
https://sandeepmistry.github.io/arduino-nRF5/package_nRF5_boards_index.json
https://github.com/tenbaht/sduino/raw/master/package_sduino_stm8_index.json