Stuff

oldbuttons = 0;  while(1) {    // if one works out the math, bits there are left, changed,    // and are now 0	if ((changes = ((PINA ^ oldbuttons) & oldbuttons)) != 0x00) {	if (changes & 0x01)  control++;  // button 1	if (changes & 0x02)  control--;  // button 2            lcdGotoXY(0,1); // Char 1, LCD Line 2        rprintf("Control %d  ",control);	oldbuttons = PINA;	}	error = position - control;        if (error > 255) error = 255;	    if (error < -255) error = -255;        SetSpeed(error);           }}