Milesight UC300: Industrial LoRaWAN Controller & Modbus Bridge

function decodeUplink(input) {
  var bytes = input.bytes;
  var data = { di: {}, do_: {}, modbus: {} };

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

    // Device info (join / power-on): protocol version, SN, hw/fw version
    if (channel === 0xff) { i += deviceInfoLen(type); continue; }

    // Digital input, digital mode: 1 byte (0/1)
    if (type === 0x00) { data.di["ch" + channel] = bytes[i]; i += 1; continue; }

    // Digital input, counter mode: UINT32 little-endian (4 bytes)
    if (type === 0xc8) { data.di["ch" + channel] = readUInt32LE(bytes, i); i += 4; continue; }

    // Digital / relay output: 1 byte (0/1)
    if (type === 0x01) { data.do_["ch" + channel] = bytes[i]; i += 1; continue; }

    // Modbus channel: data type (1 byte) + value (4 bytes)
    // channel-to-register mapping is deployment-specific
    data.modbus["ch" + channel] = readModbusValue(bytes, i); i += 5;
  }
  return { data: data };
}

function readUInt32LE(b, i) {
  return ((b[i+3]<<24)|(b[i+2]<<16)|(b[i+1]<<8)|b[i]) >>> 0;
}
function readModbusValue(b, i) {
  return { type: b[i], raw: readUInt32LE(b, i + 1) };
}
function deviceInfoLen(type) {
  void type; // 0xFF segment lengths are firmware-specific; set per deployment
  return 1;
}