alvesjc:
Ok ok ok, if I get it right, that means that I'll not need to add the ampersand to "portOutputRegister(digitalPinToPort(13))" as your previous suggestion, because "( &(port->PIO_PDSR) )" will already return that pointer, right?
exactly.
alvesjc:
By the way, can you explain me the meaning of "->"? Or point me to some place to read about it?
when you have a pointer to a structure the "->" operator is used to access a member of the pointed structure. Without this operator you should write something like:
(*PIOA).PIO_PDSR
whete *PIOA is the structure instance pointed by PIOA and .PIO_PDSR is the member selector. You need also the parenthesis because . has higher priority versus *. Since this kind of access is used very often, the C language defines the -> operator so you can write a more concise:
PIOA->PIO_PDSR
if you need more info a google search for "pointer to structure" will give you a lot of articles.