Failure when frame counter reaches 65535 (mDot v2.0 firmware issue?)

I’m seeing evidence that this bug has cropped up again. Basically, the frame count in lora-app-server does not go higher than 65535 and loraserver reports “invalid fcnt or mic” . Can anyone confirm?

I’ll see if I can reproduce this issue tomorrow. Please report bugs at the GitHub repo in the future :slight_smile: The forum is better for discussions, the GitHub issues better for bugs / tasks. I did see you posted a comment on GitHub, but then you removed it again? What is the type of your node (vendor, type, node firmware)?

Great, i’m using Multitech mDots with the 2.0 firmware.

Thank You

Looks like this has something to do with the mDot firmware. I’ve updated to the latest version (3.0) and no longer see the issue.


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Great, I was about to start debugging this :slight_smile: Note that the device only transmits the 16 LSB of the (usually) 32 bit frame-counter, but uses the 32 bits to calculate the MIC. Maybe the v2 firmware did not use the 16 MSB for the hash calculation?

(I tried to reproduce this with a RN2483 device, but I don’t see any issues when the fCnt reaches 65535)