/*
      exp6e.c - sinewave generator using a 2nd-order resonator
*/
#include <math.h>  

#define F   300                /* Frequency */
#define Fs  8000               /* Sampling frequency */
#define PI  3.1415926 

#define N	1024
#define A	cos(2*PI*F/Fs)     /* Calculate coefficient */
#define D	sin(2*PI*F/Fs)     /* Calculate excite signal */

int  w[2];
int  cos_w;
int  x[N];           

extern void sine(int *, int *, unsigned int, int);

main()
{
    /* Initialization */   
    w[0]=(int)(0x7fff*D+0.5);  /* Determine the excite signal */
	w[1]=0;	
	cos_w=(int)(0x7fff*A+0.5); /* Determine the coefficient */
	        
	/* Generate sinewave and saved it in buffer x[] */
    for (;;)  
    {
        sine(x,w,N,cos_w);     /* x=sin(2*PI*n*f/Fs) */
    }
}