@SuppressWarnings("SameParameterValue")
	private static long unsignedToSigned(long unsigned, final int size) {
		if ((unsigned & (1L << size - 1)) != 0) {
			unsigned = -1 * ((1L << size - 1) - (unsigned & ((1L << size - 1) - 1)));
		}
		return unsigned;
	}
Convert an unsigned long value to a two's-complement encoded
signed value.
ble/src/main/java/no/nordicsemi/android/ble/data/Data.java