XCore Exchange

Code: Select all

#include <platform.h>
#include <xs1.h>
#include "pwm.h"

#define SAMPLE_RATE 44100


port audio = XS1_PORT_1A;


long A=0x7e66;
long buf[3]={0,0x1209,0};
int val;


void sine (chanend pwm){


            buf[ 0 ] = ((A * buf[ 1 ]) >> 14 ) - buf[ 2 ];
            buf[ 2 ] = buf[ 1 ];
            buf[ 1 ] = buf[ 0 ];

            val = 32768 + buf[ 0 ];

            pwm <: val;

            delay_microseconds (10);

}


int main ( void )
{

    chan pwm;

    par {
        sine(pwm);
        pwm_server(pwm, audio, SAMPLE_RATE);
      }

    return 0;
}

Code: Select all

void sine (chanend pwm){
  while(1){
            buf[ 0 ] = ((A * buf[ 1 ]) >> 14 ) - buf[ 2 ];
            buf[ 2 ] = buf[ 1 ];
            buf[ 1 ] = buf[ 0 ];

            val = 32768 + buf[ 0 ];

            pwm <: val;

            delay_microseconds (10);
  }
}