TTN Getting And Transmitting Wrong Data

Hey Guys, Im a Newbie here so please bare with me.

Ive got an Ursalink gateway and (2) temp and humidity sensor nodes and ive got them reporting to TTN and Cayenne is grabbing the data “fine”

I say “fine” because the Rssi And Humidity Seems about right but the temp is Totally off, at least 100 degrees c.

When i log into the node directly everything is prefect but its reporting something different to TTN.

Is there anything that i can do to solve this?


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That’s probably not a TTN problem (the data has cryptographic checksums, if it were corrupted, passing the checks anyway would be an extremely rare coincidence) but rather a software bug in the value encoding or decoding.

Get the bare data of the decrypted packet and decode it by hand and see if that makes sense.

Many attempts to write things like javascript decoders to run online fail over subtle bugs with things like sign extension, etc.

If all else fails, modify the node firmware to print out (on the debug serial port) the reading, then a hexdump of the plaintext packet to be sent - which should be the same as the decrypted packet you get from TTN.

I think this because you choose Cayenne LPP decoder type? Ursalink sensor payload strucuture has differences with Cayenne format:
You could choose Custom decoder and add the decoder example to check it.