This code is made to be flashed on the Nucleo STM32 microcontroller.
It is working with Visual Studio code and its extension platformio that allows to flash codes on multiple microcontrollers without using their own platforms.
To flash the code, you first need to build it. Then, you will have to go in the Explorer, select the .pio repository, then build, then nucleo_f303k8 and open the file "firmware.bin" in your file explorer.
Once it is done, copy it and paste it into the Nucleo memory (that oppens when you link the nucleo to your PC).
