How can I validate the LoRa MIC value on the NUCLEO-WL55JC1?

[moatjon]

Hi everyone,

I am trying to connect a NUCLEO-WL55JC1 to the TTN network. I have specified the device EUI, app/join EUI, app key and network key in the se-identity.h file. The debug output of the board confirms that the values correspond to the values specified in the TTN application. The join request fails, but I can see that the request is received by the gateway and it makes its way to the application in the TTN console. The data in the TTN console shows that the OTAA join request failed because of a MIC mismatch. If I copy the raw payload and decode it using this online decoder I can indeed see that the received MIC does not correspond to the expected MIC.

Now my question is: How do I check the if the MIC is calculated in the right way? I have a feeling my device is using the wrong credentials to calculate the value, but I am unable to pinpoint where this happens in the swamp of the LoRaWAN-stack.

I am also unable to find what LoRaWAN version and Regional Parameters version I need to select in the TTN console. The debug output mentions a "MW_LORA_VERSION" V2.2.1, but in the TTN console I must select a version between V1.0 and v1.1.

Thanks in advance.

[CDenk.1]

Dear @moatjon​ , could you solve this problem? I have the same issue with a WLE5JC1 board.

[FRest.1]

Set the LORAWAN_NWK_KEY instead of the app/join EUI. This is the key used by the join process.

[CDenk.1]

Yes, thank you very much! I found it out last night after many failed join requests.

[FRest.1]

Fine. I think this is an issue, a misconfigured variable name. All LoRaWAN documentation reports appKey as the key used in the join phase. :(

Che dire?

F.