A list is returned containing the latch state for the pin, the
        latched value, and the time stamp
        [pin_num, latch_state, latched_value, time_stamp]

        :param pin: Pin number.

        :returns:  [latched_state, threshold_type, threshold_value,
                   latched_data, time_stamp]

async def get_digital_latch_data(self, pin):
        """
        A list is returned containing the latch state for the pin, the
        latched value, and the time stamp
        [pin_num, latch_state, latched_value, time_stamp]

        :param pin: Pin number.

        :returns:  [latched_state, threshold_type, threshold_value,
                   latched_data, time_stamp]
        """
        key = 'D' + str(pin)
        if key in self.latch_map:
            entry = self.latch_map.get(key)
            return entry
        else:
            return None