Help needed for payload decoding (LMIC)


(Hans) #1

After hours of trying I must kindly ask for some help with payload decoding. Within an Arduino sketch a value of 1111 is defined:

int value = 1111;
message[0] = highByte(value);
message[1] = lowByte(value);

I send it, using the LMIC library, from the line:

LMIC_setTxData2(1, message, sizeof(message), 0);

This results in the TTN console to the next physical payload:

40 B8 1D 01 26 80 00 00 01 9A A8 74 89 01 CD

When I change the value to 1234 the payload becomes:

40 B8 1D 01 26 80 00 00 01 9A 2D 2B 5A 78 49

So far so good but after many tries I did not succeed decoding the payload to the value 1111 or 1234. Can somebody help me with the right code to use with the TTN Payload decoder?


(Ud Lo Ra) #2

Are you looking at the gateway console or at the application console?


(Hans) #3

The Physical Payload was copied from the Gateway Traffic page. From the Application Overview page I choose Payload Formats. There I tried to decode the payload. Am I wrong…?


(Ud Lo Ra) #4

Check in the application data tab. On the gateway you will see encrypted payload.


(Hans) #5

Thanks for your kind support! My Application Data screen stays empty… Yes, I’m a newbie…

app-data


(Hans) #6

I think my problem is solved. First I tried (as UdLoRa said) to decode the encrypted payload from the Gatway Traffic page which was wrong. Second I had to reset the frame counters on the device page, therafter I see payloads showing up in Application Data :wink:


(Ud Lo Ra) #7

Until you have a stable setting, you may disable the frame counter; then for security is better to have it enabled, but when you restart the node, if the internal counter is not saved, it will start again from zero.