Generic LoRaWAN

If your LoRaWAN device is not Efento and not on the OpenSense supported list, you can still route it through TTN. You need three things:

1. The device has a payload decoder (or you write one) that produces JSON.
2. TTN has an HTTP webhook integration pointed at OpenSense.
3. OpenSense knows how to map the JSON to your sensor channels.

Step 1 — write the payload decoder

TTN runs a JavaScript function per uplink. The function gets the raw bytes, returns an object that OpenSense ingests.

Example for a Dragino LHT65 (T + ext probe T):

function decodeUplink(input) {
const b = input.bytes;
// Dragino LHT65 v1.x payload format
const battery = ((b0 << 8) | b1) / 1000.0;            // V
const t_int   = ((b2 << 8) | b3) / 100.0;             // °C
const rh_int  = ((b4 << 8) | b5) / 100.0;             // %
const t_ext   = ((b7 << 8) | b8) / 100.0;             // °C (DS18B20)
return {
data: {
measurements: 
{ type: 'temperature',  value: t_int, label: 'internal' },
{ type: 'humidity',     value: rh_int },
{ type: 'temperature',  value: t_ext, label: 'probe'    },
{ type: 'battery',      value: battery, unit: 'V'       }

}
};
}

The shape OpenSense expects:

{
  "measurements": [
    { "type": "<kind>", "value": <number>, "label": "<optional>", "unit": "<optional>" }
  ]
}

type must be one of: temperature, humidity, pressure, co2, voltage, current, power, leak, battery, signal. Unknown types are ignored. label distinguishes multiple sensors of the same type on one device (e.g. two probes).

Step 2 — webhook to OpenSense

Same as for Efento:

• Application → Integrations → Webhooks → + Add → JSON.
• Paste the OpenSense ingest URL from + ADD DEVICE → LORAWAN → Generic.
• Enable Uplink message.

OpenSense uses the DevEUI from the TTN payload metadata to identify the device. If you have not registered the DevEUI in OpenSense yet, the first uplink lands in the unassigned tray on the site page; click to associate.

Step 3 — map channels

OpenSense auto-creates a channel per type + label combination on first uplink. Initial thresholds are pulled from the vertical preset of the site. For example, a HACCP site auto-creates a temperature channel with [−2 °C, +8 °C] operating range. Edit per-channel afterwards.

A note on FPort

Some LoRaWAN devices send different payload shapes on different FPort values. The payload decoder can switch on input.fPort to handle them:

function decodeUplink(input) {
  if (input.fPort === 1)  return decodeReadings(input.bytes);
  if (input.fPort === 99) return decodeConfig(input.bytes);
  return { errors: ['unknown fport'] };
}

OpenSense ignores anything that is not measurements. Config uplinks are fine, they are simply dropped at the ingest.

Devices we have tested

If you get a device working that is not on the list, send the decoder via GitHub and we will add it.