Wrong device address

Hello, I have a single channel gateway, on a Raspberry PI 3b+ running a Dragino shield with the stock antenna.
And I also have a TTGO ESP32 V1.0 it is running Arduino LMIC 1.5 library with ttn-abp example, It has some package loss, but the main issue is that the device address is almost always wrong.
the right device address is highlighted.
What could be the issue? :slight_smile:

Are you forwarding packets with crc errors? Because it looks like the backend receives ‘defective’ data.

What is the distance the node and your gateway? Anything below 3 meters will probably result in the ‘gateway’ receiving mangled data due to over modulation.

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@kersing is probably right. So just to be sure, a few additional things for debugging:

  • Looking at the uplink counters, the two messages for DevAddr 01002601 (for your single missing counter value 1) might also indicate you’re simply seeing traffic for other nodes. However, looking at their counters, 35876 followed by the lower 29585, would then imply those are two different nodes. That’s very well possible, as a DevAddr is not unique. But chances that all nodes are sending payloads of 26 bytes, are low. In short: make sure that the times in TTN Console match the expected transmissions of your node.

  • Looking at the timestamps, the 2nd message is less than 1 second after the first. On SF7BW125, 26 bytes take 61.9 ms to transmit. (Ah, TTN Console shows 61.7 ms; maybe my math is wrong.) Hence, assuming a 1% duty cycle, there should be at least 6.1 seconds between two transmissions, and LMIC should enforce that, even more so when only using a single channel for testing. So: how often is your node transmitting?

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  1. The timestamps match.
  2. I just reset my device when I want it to send a payload.