PWM demo for the PiFace by Gordon of drogon.net

pifacePwm.c

/*
 * pifacePwm.c:
 *	Simple test for the PiFace interface board.
 ***********************************************************************
 */

#include <wiringPi.h>
#include <softPwm.h>

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>

#define	START	2
#define	END	7

int main (void)
{
  int i, j ;

  printf ("Raspberry Pi PiFace + PWM test program\n") ;

  if (wiringPiSetupPiFace () == -1)
    exit (1) ;

  for (i = START ; i <= END ; ++i)
    softPwmCreate (i, 0, 100) ;

  for (;;)
  {
    for (i = 0 ; i <= 100 ; ++i)
    {
      for (j = START ; j <= END ; ++j)
	softPwmWrite (j, i) ;
      delay (20) ;
    }

    for (i = 100 ; i >= 0 ; --i)
    {
      for (j = START ; j <= END ; ++j)
	softPwmWrite (j, i) ;
      delay (20) ;
    }
  }

  return 0 ;
}