iir55.c

DSP开发IIR滤波器,包括.asm .c .cmd格式三个文件.可直接出结果

#include "math.h"
#define signal_1_f 500
#define signal_2_f 10000
#define signal_sample_f 25000
#define pi 3.1415926
#define IIRNUMBER_L 2
#define bufer_L 256
int N_L=IIRNUMBER_L; 
int data_in[bufer_L];
int out[bufer_L] ;
int x[IIRNUMBER_L+1];
int y[IIRNUMBER_L+1];
int k=0;
int bufer=bufer_L;
int fBn[IIRNUMBER_L]={0,0x634a};
int fAn[IIRNUMBER_L]={0xe5c,0xe5c};
extern int iir(int *x,int *y,int *fAn,int *fBn,int N_L);
extern int init(int *,int *,int);
extern int outdata(int *,int,int);
void inputwave();
void main()
{
int iirout;
inputwave();
init(x,y,N_L);
while(1)
{
x[0]=data_in[k];
iirout=iir(x,y,fAn,fBn,N_L);
outdata(out,iirout,bufer);
k++;
if(k>=bufer_L)
{
k=0;
}
}
}
void inputwave()
{
float wt1;
float wt2;
int i;
for(i=0;i<=bufer_L;i++)
{
wt1=2*pi*i*signal_1_f;
wt1=wt1/signal_sample_f;
wt2=2*pi*i*signal_2_f;
wt2=wt2/signal_sample_f;
data_in[i]=(cos(wt1)+cos(wt2))/2*32768;
}
}