wiringSam

wiringSam is a little library to easily access to GPIOs pins of an Atmel AT91SAM like on "Arduino" cards.

It is written in C, using direct memory access with mmap().

Version 0.1 - 28 August 2015

Usage :

To use it, just add the 2 files : wiringSam.h and wiringSam.c to your files project.

Then in your code,
at the top, add line: #include "wiringSam.h"

List of functions available :

int wiringSamSetup( void ) => should be called first
void wiringSamEnd( void ) => to call at end of your program (optional)
void pinMode( int controller, int pin, int mode ) => select pin between INPUT/OUTPUT
void pullUpDnControl( int controller, int pin, int pud ) => set pull-up (PUD_UP) / pull-down (PUD_DOWN) / none (PUD_OFF) on the input pin
int digitalRead( int controller, int pin ) => give state of the input pin: LOW/HIGH
void digitalWrite( int controller, int pin, int value ) => set state of the output pin: LOW/HIGH

in previous fonctions:
controller = WSAM_PIO_A / WSAM_PIO_B / WSAM_PIO_C/ WSAM_PIO_D to select A/B/C/D controller PIO
pin = 0 to 31.

void delay( unsigned int howLong )
void delayMicroseconds( unsigned int howLong )
unsigned int millis( void )
unsigned int micros( void )

Typical examples of use :

To read state of an input pin :
pinMode( WSAM_PIO_C, 17, INPUT );
printf( "Value of bit_17/PIO_C : %s\n", digitalRead( WSAM_PIO_C, 17 )?"HIGH":"LOW" );

To flash an output pin in loop :
pinMode( WSAM_PIO_C, 0, OUTPUT );
for( ; ; )
{
digitalWrite( WSAM_PIO_C, 0, HIGH );
delay( 500 ); //ms
digitalWrite( WSAM_PIO_C, 0, LOW );
delay( 500 ); //ms
}

See little example code included in the archive: "test_at91sam_gpio.c".

Tested on the Arietta G25 board by AcmeSystems (low-cost Linux embedded module).