function toHex(dec) {
	hexChars = "0123456789ABCDEF"
	if (dec > 255) {
		return null
	}
	var i = dec % 16
	var j = (dec - i) / 16
	result = "0X"
	result += hexChars.charAt(j)
	result += hexChars.charAt(i)
	return result
}
