I’m using cayenne and arduino to communicate with a solar system controller, getting data from it and setting parameters.
I’m using the ethernet shield on the arduino not only to communicate with cayenne but also with the solar controller, so my arduino is not always able to receive the data from the dashboard as it may be busy for something esle.
So when I set a parameter on the dashboard, the arduino can’t always get it, as it is sometimes connected to the solar controller and not to cayenne. I would need my arduino to get the parameter from the dashboard once it reconnects.
I found that the mqtt protocol could be used in QoS 2, meaning that the broker would keep the message from the emitter as long as the receiver does not confirm the good reception, I think it may be helpful in my case, but I could not find out how to use this mode.
Thank you for any help !