Dragino LSE01 Payload Decoder

Decode Dragino LSE01 LoRaWAN payloads online: battery, soil moisture, soil temperature and conductivity (EC), with Dragino's exact negative-temperature formula. Includes payload structure, verified examples and a decodeUplink codec for ChirpStack v4 and The Things Stack.

Example payloads

Payload structure

Ready-to-use codec

ChirpStack v4 and The Things Stack share the same decodeUplink(input) signature: paste this into the device profile codec (ChirpStack) or the payload formatter (TTN).

function decodeUplink(input) {
  var b = input.bytes;
  function u16(i) { return (b[i] << 8) | b[i + 1]; }
  function int16(i) { var v = u16(i); return v >= 0x8000 ? v - 0x10000 : v; }
  var soil = u16(6);
  return {
    data: {
      battery: (u16(0) & 0x3FFF) / 1000,
      temp_ds18b20: int16(2) / 10,
      soil_moisture: u16(4) / 100,
      soil_temperature: (soil & 0x8000 ? soil - 0xFFFF : soil) / 100,
      soil_conductivity: u16(8),
      mod: b[10] >> 7,
      interrupt: b[10] & 0x0F
    }
  };
}

About the LSE01 uplink

The Dragino LSE01 measures soil moisture, soil temperature and electrical conductivity (EC) — the core trio for precision-agriculture irrigation decisions. It reports on FPort 2 as a fixed 11-byte, big-endian frame.

Decoder pitfalls specific to this device:

• Mask the battery. The top two bits of bytes 0–1 are not voltage; without the 0x3FFF mask a fresh battery reads as ~52 V.
• Dragino’s negative-temperature quirk. The official decoder computes negative soil temperatures as (raw − 0xFFFF) / 100 — one less than standard two’s complement. 0xFF7E is −1.29 °C, not −1.30 °C. This tool reproduces the official behavior exactly.
• No probe ≠ error. With no DS18B20 attached, bytes 2–3 simply read 0x0000. There is no 0x7FFF sentinel on this model (unlike the LHT52/65).
• Check the MOD bit. If bit 7 of the status byte is set (firmware ≥ 1.2.1 raw mode), bytes 4–9 carry the dielectric constant and raw AD values instead of calibrated readings — this tool warns when it sees it.
• EC is unscaled µS/cm; values in fertilized soil can exceed 20000.

References

• Dragino LSE01 user manual (payload sections 2.3.1–2.3.7) — wiki.dragino.com
• Official decoder: github.com/dragino/dragino-end-node-decoder, LSE01/ (v1.2.1)