* MicroPython on STM32
  
  * To update/modify software on STM32 board:
  ** Connect your computer to the CN5 connector (mcro-USB Type B).
  ** You should have access to the flash of the STM32 board (on my computer a  mountpoint called "PYBFLASH" is created).
  ** Put files of your new software.
  ** That's all
  
  
  * Architecture of a (u)Python software:
  ** You need a main file "boot.py" which is read on boot-up.
  ** The "boot.py" file must be, in general, minimalist. For example:
  --
  import pyb
  pyb.main('my_super_software.py')
  --
  In the example, "boot.py" run the file "my_super_software.py"
  ** Your software can be, as your convenience, composed of several files.
  
  * You can access to a uPython prompt (start/stop program, see error...).
  On Linux: use the command: "screen /dev/ttyACM0"
  On other system: use Google or whatever, I don't care.
  
  * Micropython documentation
  https://docs.micropython.org/en/latest/index.html
  
  * Please visit http://micropython.org/help/ for further help.