protected static boolean isOpCodeValid(int opCode) {
		return ((opCode >= 0 && opCode <= 31) && !(opCode == 2) && !(opCode == 15) && // valid ranges: 0-1, 3-14, 16-19, 24, 31
				!(opCode >= 20 && opCode <= 23) && !(opCode >= 25 && opCode <= 30)); // temporary measure for valid ranges
	}