I just noticed that platformio now supports the Sipeed boards thanks to the Sipeed team. Very nice! I love working with platformio.
The only problem I had was that when trying to upload the firmware with ‘platformio run --target upload’ (compiling works good). Platformio says that I need to install enum34 via pip. However, kflash uses python3, which in my case is linked through to python3.5, and enum34 is not supported in python3.5. However, if I use kflash without platformio it works fine:
So, I do not know what causes the enum34 problem.