## Correlation on DSP KIT TMS320C6713 Simulator

December 15, 2010 Coded in C++ for the TI C67x

This code does the correlation of two signal over DSP kit TMS320C6713 simulator. Two sine signals are generated from the DSP kit whose correlation is performed in simulator.

``````#include <stdio.h>
#include <math.h>

double pi=3.14159;

float x,y;
float r;

void correlation(float *x,float *y, int nx, int ny);

int main()
{

int ii;
for(ii=0;ii<50  ;ii++)
{
x[ii]=sin(2.0*pi*ii*3/50);
y[ii]=sin(2.0*pi*ii*3/50);

}

correlation(x,y,50,50);

printf("Complete.\n");

return 0;
}

void correlation(float *x,float *y, int nx, int ny)
{
int n=50,delay=0,maxdelay=50;
int i,j;
double mx,my,sx,sy,sxy,denom;

/* Calculate the mean of the two series x[], y[] */
mx = 0;
my = 0;
for (i=0;i<n;i++)
{
mx += x[i];
my += y[i];
}
mx /= n;
my /= n;

/* Calculate the denominator */
sx = 0;
sy = 0;
for (i=0;i<n;i++)
{
sx += (x[i] - mx) * (x[i] - mx);
sy += (y[i] - my) * (y[i] - my);
}
denom = sqrt(sx*sy);

/* Calculate the correlation series */
for (delay=-maxdelay;delay<maxdelay;delay++)
{
sxy = 0;
for (i=0;i<n;i++)
{
j = i + delay;
if (j < 0 || j >= n)
continue;
else
sxy += (x[i] - mx) * (y[j] - my);
// Or should it be (?)
/* if (j < 0 || j >= n)
sxy += (x[i] - mx) * (-my);
else
sxy += (x[i] - mx) * (y[j] - my);*/

}
r[delay+maxdelay]= ( sxy / denom);``````