RogerClark wrote:Did you make a new board variant folder etc?
No, not yet.
First, I uploaded the STM32duino bootloader to the blank GD32F103VET6 chip (keeping the 8MHz crystal), using the ST-Link Utility program.
Then, I switched to USB connection and opened Arduino, selected STM32F103V variant and tried to compile and upload a blink sketch (PB9 led). It didn't work, when I plugged in the board in the USB I got a 'USB device not recognized', then when I tried to upload it failed..
Then I changed the quartz crystal with a 12MHz one, wrote the GD32duino bootloader using the ST-Link Utility program. Switched to Arduino, selected GD32F103C variant, connected the board via USB...got the same error as above..
The same procedure applied to a different board with STM32F103VCT6 chip works very well.
Do you have an idea what could be the problem? Am I doing something stupid here?