Documentation for using GPIO

[Luiz Otavio O Souza]

On 29 September 2014 21:16, Erich Dollansky wrote:
> Hi Luiz,
>
> On Mon, 29 Sep 2014 16:27:26 -0300
> Luiz Otavio O Souza wrote:
>
>> > is there some documentation available of how to use GPIO on a
>> > Raspberry Pi B+ than man gpio, man gpioctl etc?
>> >
>> Unfortunately not, there is the Wiki page
>> (https://wiki.freebsd.org/FreeBSD/GPIO) but it doesn't add much.
>>
> I ave read this.
>
>> But we can try to help you whenever possible, just post your questions
>> and we'll try to address them.
>
> I am currently working on a C program which should use GPIO to switch
> relais and read the state of switches via GPIO. I would like to make
> this program as simple as possible by creating first a layer which
> provides then functions like set (Pin), reset (Pin)  and read (Pin)
> only. Of course plus the things needed to open, close and configure the
> interface.
>
> The best I have found until now are the sources of gpioctl. I am
> currently looking at the source.
>
> Is this the best start?

You can use the excellent rpaulo's libgpio:

https://bitbucket.org/rpaulo/libgpio/src/1dfe793d0b0cd6caff2e196cf667a5c06bbade8d/libgpio.h?at=default

It provides all the GPIO low level functions in a clear and simple way.

Luiz