Wio Lite RISC-V

Tried to compile https://wiki.seeedstudio.com/Wio_Lite_RISC_V_GD32VF103_with_ESP8266/#software-code but got errors. Serial is not available. Is there another part of code required for that?

Here is my pio.ini:

platform = gd32v
board = gd32vf103v-eval
framework = arduino
monitor_speed = 115200
upload_protocol = dfu

Is there a compilation error?

Yes, as I mentioned. Serial is not declaired.

This Arduino Core is being maintained by Sipeed, and they don’t seem to be paying much attention to it.