Milesight EM310-UDL: LoRaWAN Ultrasonic Level Sensor

function decodeUplink(input) {
  var bytes = input.bytes;
  var data = {};

  for (var i = 0; i < bytes.length; ) {
    var channel = bytes[i++];
    var type = bytes[i++];

    if (channel === 0x01 && type === 0x75) {          // battery (%)
      data.battery = bytes[i]; i += 1;
    } else if (channel === 0x03 && type === 0x82) {   // distance (mm)
      data.distance = readUInt16LE(bytes, i); i += 2;
    } else if (channel === 0x04 && type === 0x00) {   // position (tilt)
      data.position = bytes[i] === 1 ? "tilt" : "normal"; i += 1;
    } else {
      break;
    }
  }
  return { data: data };
}

function readUInt16LE(b, i) {
  return (b[i + 1] << 8) | b[i];
}