OTA activation - join transaction sending incorrect tx frequencies to end node

Hi All

I am not sure why TTN is sending me incorrect frequencies to transmit on when joining using OTAA. See trace below. Any assistance will be appreciated.

------------------JOIN---------------ALL GOOD HERE---------------------------------------

[INFO] attempting to join
[TRACE] Join Network - OTA
[TRACE] Number of enabled channels: 3
[TRACE] Check freq: 868100000
[TRACE] Frequency 868100000 is free.
[TRACE] Preparing frame
[TRACE] FRAME_TYPE_JOIN_REQ
[TRACE] Set Frequency: 868100000
[DEBUG] Send on normal lora channel
[TRACE] Frequency: 868100000 Datarate: 12 BW: 125 POW: 20
[DEBUG] Time on air: 23 bytes 1482 ms
[TRACE] Band: 1 100
[TRACE] Duty cycle: 0.1%
[DEBUG] Time off air: 1482000 ms

--------------------------JOIN ACCEPT FROM THE TTN--------------BUT CHECK THE CHANNEL FREQUENCIES THAT I AM RECEIVING---------------

[TRACE] Received packet SIZE: 33 bytes RSSI: -126 dB SNR: 121 cB
[TRACE] Rx Packet Type: 1 Size: 33
[TRACE] FRAME_TYPE_JOIN_ACCEPT
[TRACE] BUFFER:
[TRACE] PAYLOAD SIZE: 33
[TRACE] APPKEY:
[TRACE] PAYLOAD:
[TRACE] mic:
[DEBUG] Network joined
[TRACE] DNONCE:
[TRACE] ANONCE:
[TRACE] Computing session keys…
[TRACE] NETS:
[TRACE] APPS:
[TRACE] NetID:
[TRACE] DevAddr:
[TRACE] rxDrOff: 0 rx2Dr: 3 rxD1: 5000 rxD2: 6000
[TRACE] Add Channel Frequency 159322000
[TRACE] Add Channel Frequency 1522650000
[TRACE] Add Channel Frequency 1208282000
[TRACE] Add Channel Frequency 893914000
[TRACE] Add Channel Frequency 579546000

-----------------------NOW MY DEVICE IS TRANSMITTING ON ONE OF THOSE INCORRECT FREQUENCIES---------------

[TRACE] Number of enabled channels: 5
[TRACE] Check freq: 1522650000
[TRACE] Frequency 1522650000 is free.
[TRACE] Preparing frame
[TRACE] FRAME_TYPE_DATA_UNCONFIRMED_UP
[TRACE] Encrypting application packet to buffer…
[DEBUG] payload:
[DEBUG] address:
[DEBUG] dir: 0
[DEBUG] sequenceCounter: 0
[TRACE] Set Frequency: 1522650000
[DEBUG] Send on normal lora channel
[TRACE] Frequency: 1522650000 Datarate: 7 BW: 125 POW: 11
[DEBUG] Time on air: 27 bytes 66 ms
[TRACE] Band: 0 1000
[TRACE] Duty cycle: 0.1%
[DEBUG] Time off air: 66000 ms
[TRACE] Rx Window 1 - Frequency: 1522650000 Bandwidth: 0 Datarate: 7
[INFO] RxTimeout
[TRACE] Rx Window 2 - Frequency: 869525000 Bandwidth: 0 Datarate: 9
[INFO] RxTimeout
[TRACE] Windows Expired

Weird case. Perhaps I am missing something? Surely the network server should have sent frequencies on the 868/9MHz band for my end device to use?

Are you sure your LoRaWAN stack is interpreting the MAC payload correctly? Which stack are you using?

Thanks Kersing.

I’m using the multitech mdot box evb.

I took your comment into consideration and updated the firmware on the unit.

Sorted now.

Perhaps others should do the same if they experience a similar issue.

-Reshamg

2 Likes