Hi, i’m trying to understand the way to read the values that uplink the tags in the range of the Gateway, the message has this topology (or Payload?) :
{“position”:{“x”:2.39,”y”:4.18,”z”:0.3,”quality”:66},”superFrameNumber”:916}
Picture to understand:
So i want to know the function that writes this or how can i read/write this.
Im using C to read this message, but cant do it at the moment.
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Hi FrancoCapararoArg,
1, This messages are in Json fomat, if you are using C , please search Cjson , there are many open source Cjson source file, you only need add the source file in your project.
2, In our project, just use mmap/fread/fwrite/ to operate the file according to the directory you showed in the picture.
Thanks
Jesen
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jesen_CN:
Json fomat
yes, but when i write in Json format, i cant receive nothing… just a /node/uplink/status saying “false”.
Hi, im having some trouble to send the Location to the server:
2019-05-10 18:35:06,966 INFO --- MqttFX ClientModel : messageArrived() with topic: dwm/node/5a81/uplink/status
2019-05-10 18:35:06,967 INFO --- MqttFX ClientModel : messageArrived() added: message #29 to topic 'dwm/node/5a81/uplink/status'
2019-05-10 18:35:45,109 INFO --- MqttFX ClientModel : rebuildMessagesList()
2019-05-10 18:35:45,110 INFO --- MqttFX ClientModel : attempt to add…
Hi Franco,
what do you mean with writing? Do you mean to publish data to the node? If so, you need to publish to the downlink topic, see this post:
Hi Thorsten,
yes, as Yves has written, you can send it easily by publishing a MQTT message to the MQTT broker on your gateway.
If you subscribe to the broker using e.g. mosquitto_sub, you can see the format of data. E.g. run this on your Raspberry PI:
$ mosquitto_sub -h localhost -t ‘dwm/node/+/downlink/#’
and then send some user data via the Web Manager. You should see something like:
dwm/node/11cb/downlink/data {“data”:“ASNFZ4mrze8=”,“overwrite”:false}
Similarily you can publish using mo…
Another MQTT library option is to use Mosquitto libraries:
https://mosquitto.org/api/files/mosquitto-h.html
Cheers,
TDK
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