mosquitto_pub question

[Eduardo Garcia]

Hi:

I am trying ty send data to my LoRa device, with no luck. My device ID on the network is 33:33:33:31. I check on the lora-network log and using mosquitto_sub that I am getting messages. However, I try the following:

mosquitto_pub -t lora/33:33:33:31/down -m 'D'

To transmit only a character, with no luck. Am I missing something, or is there a way to know that the conduit is trying to send the data?

Thanks,

-Ed

[Eduardo Garcia]

Hi:

I noticed I mad a mistake, I should use the DevEui, which is 8 bytes in length. However, with that change I still do not receive messages on my device. My device is actin as Class A, and I am receiving messages on the Conduit correctly.

Thanks,

-Ed

[Brandon Bayer]

Eduardo,

Look at the transmit section of this page:

Conduit mLinux: LoRa Communication

As noted there,

The packet must be in JSON format and the data must be Base64 encoded

-Brandon

[Eduardo Garcia]

Hi Brandon:

Thanks, you are right. I did change the message to be the following:

mosquitto_pub -t lora/01:02:03:04:05:06:07:08/down -m '{ "data":"aGVsbG8=" }'

with the device EUI verified to be 01:02:03:04:05:06:07:08 as noted on node list:

Net Addr     Dev EUI                  Joined                Seq Num       Up     Down      1st      2nd  Dropped  RSSI min   max   avg  SNR min   max   avg
33:33:33:32  01:02:03:04:05:06:07:08  2015-11-25T09:00:33Z      154     1173      946      923       23        0      -121    -9   -96    -16.5  13.8  -4.7

But I still do not receive anything. Is there a way to see if the Conduit has tried to send the message on the receive frames? Thanks!

[Brandon Bayer]

Eduardo,

Sure, you should be able to see all receive and transmit activity in /var/log/lora-network-server.log

-Brandon

[Eduardo Garcia]

Brandon:

Thank you for your reply. In the device side I seem to get a response, but it does not detect a payload. Does the mosquitto command send whatever is in the “data” parameter as the payload?

Thanks!

[Brandon Bayer]

Eduardo,

Yes the data value is transmitted as the payload.

-Brandon

[Eduardo Garcia]

Hi Brandon:

It seems that my device (Nucleo Board with the LoRaWAN-lmic-app from SemTech in mBed, available https://developer.mbed.org/teams/Semtech/code/LoRaWAN-lmic-app/) needs that we also especify the port. For example, the following code in the conduit was received correctly:

mosquitto_pub -t lora/01:02:03:04:05:06:07:08/down -m '{ "data":"aGVsbG8=", "port":6 }'

I hope this may be of use to somebody now or in the future using the same devices I am using now!

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