Process the floating-point data in BF518

My processor is BF518. Recently, I need to process some floating-point data in the BF518. I want to process some data to get the same result in the PC and the BF518. Like this example.

#include"stdio.h"

#include"float.h"

int main( void )

{

    float y,x=0.6;

    int u=4;

    int i;

    for(i=0;i<100;i++)

    {

        y=u*x*(1-x);

        x=y;

    }

    printf("x = %f\n",x);

}

My PC is win7-32bits. When I run this process in the PC, I get the result is 0.172498. But I get the result is 0.288682 in the BF518. How can I slove this problem.

I know the Blackfin is fixed-point processor.