dragino / ldds75

Dragino LDDS75

The LDDS75 is a LoRaWAN ultrasonic distance / level sensor. Battery voltage and distance are always present; temperature may read as 0 if the optional sensor is not fitted.

Output (typical)

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Decoder

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// MetSci Support — Dragino LDDS75 (ultrasonic distance / level)
// Source adapted from MeteoScientific docs. Verify payload against your FW version.

function decodeUplink(input) {
  const decoded = {};
  try {
    const bytes = input.bytes;
    const batValue = ((bytes[0] << 8) | bytes[1]) & 0x3fff;
    decoded.battery_voltage = parseFloat((batValue / 1000).toFixed(3));
    decoded.distance = (bytes[2] << 8) | bytes[3];
    if (bytes.length > 4) {
      decoded.interrupt_status = bytes[4] === 1;
    }
    if (bytes.length > 6) {
      const tempValue = (bytes[5] << 8) | bytes[6];
      decoded.temperature = tempValue & 0x8000 ? tempValue - 0x10000 : tempValue;
    }
    if (bytes.length > 7) {
      decoded.sensor_status = bytes[7] === 1;
    }
    return { data: decoded };
  } catch (err) {
    return { errors: [`Decoder error: ${err.message}`] };
  }
}