In case you fried your SWDIO/CLK pins you could still use this tool to burn firmware to MCU:
- convert ELF to BIN:
arm-none-eabi-objcopy -S -O binary build_elf out.bin- connect serial port to pins PA9/10
- set BOOT0 pin to 1 and turn power on/reset the device
- burn resulting BIN-file:
python2 stm32loader.py -p /dev/ttyUSB0 -f F3 -e -w -v out.bin- set BOOT0 back to 0 and reset.