lab4fixed

#include <reg51.h>

int x_fixed;
unsigned char xdata y[100], i;

unsigned int f(unsigned int x) {
    unsigned int S = 0x0f;
    S = 0xf0+((x*S)>>8);
    S = 0xf0+((x*S)>>8);
    S = 0xf0+((x*S)>>8);
    S = 0xf0-((x*S)>>8);
    return S;
}

main()
{
	i = 0;
	for (x_fixed = 99; x_fixed >= 0; --x_fixed)
		y[i++] = f(x_fixed);
	while(1)
	{
		i = 0;
		for (x_fixed = 0; x_fixed <= 99; ++x_fixed)
		{
			f(x_fixed);
			P1 = y[i++];
		}
	}
}