waouh ! it's an very active forum !!
The problem I have is that I have no arduino board at home. I wanted to know a little more about it before visiting my friend next week. And reading the documentation raised some questions.
For its first arduino, my friend want to manage the sidings (tracks where trains are stocked 'in the backoffice'). He thouht that programming was easy and that difficulties were with the 'hardware'. In fact, it's the opposite.
Many thanks to all
Jean