on SAMD21G18
need to be flashed by swdio swclk usin any programer, raspberry, etc
i used st-link v2 to doit
openocd.exe" -f scripts\interface\stlink-dap.cfg" -f "samdg18.cfg" -c "tcl_port disabled" -c "telnet_port disabled" -c "init" -c "reset init" -c "program...