[En-Nut-Discussion] (no subject)

[Harald Kipp]

> I'm developing an application based on Ethernut 3 and I would like to use
> the 5 GPIOs that seem to be available at the expansion port (pins: 55, 56,
> 59, 61 and 62) for digital input. Is there any problem to use them for this
> fact? For example pin 55 is used for I2C Clock. Could this produce same
> collision with my purposes?
>   
See
http://ethernut.de/en/hardware/enut3/ports.html
All pins, which got an entry in column "Internal Use" should be avoided. 
Watch the notes below the table.
> And finally, how are these pins referred in the API? What constants should I
> look?
>   

There is no special API available for this, but it is recommended to use 
outr() and inr() for register access. You need to refer to the 
AT91R40008 datasheet. Symbolic register names are defined in 
include/arch/arm/at91_pio.h.


Harald