MQTT and Fez Panda III?

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1

Dear friends,
I am a refugee from Netduino. I used MQTT (Paolo Patierno’s M2MQTT library) with the Netduino Plus 2 all the time and it was great. Tried it with my new Fez Panda III and nothing. I find some posts from 2-3 years ago about adapting to the way that Panda does its ethernet, but nothing seems to have materialized. Can anyone help ?
Thanks-

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How did you add Ethernet? Please show more details.

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I used a ENC28J60 board. Details in another (dumb) post https://www.ghielectronics.com/community/forum/topic?id=24479. Is there a different route to Ethernet that allows Panda III to support MQTT?

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Once you have initialized Ethernet, can you ping your Panda?

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Yes, I can. In the discussion from a couple of years ago, there was mention that MQTT doesn’t work because the Panda uses a GHI ethernet library instead of the .NETMF library. I don’t entirely understand this.
https://www.ghielectronics.com/community/forum/topic?id=11597
My code is below. It works fine on Netduino.

MQTTClient = new MqttClient("192.168.0.41");                  // instantiate the client, point to broker's ip address
MQTTClient.MqttMsgPublishReceived += client_MqttMsgPublishReceived;  // raised when a subscribed message is received            
MQTTClient.Connect(ModuleID);                                        // connect.  Module ID is unique string

The fail occurs on the 3rd line with error :
An unhandled exception of type ‘uPLibrary.Networking.M2Mqtt.Exceptions.MqttCommunicationException’ occurred in M2Mqtt.NetMf.dll

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That was on old Pandas. Yours users netmf networking so it should work.

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More complete error…
A first chance exception of type ‘System.Net.Sockets.SocketException’ occurred in Microsoft.SPOT.Net.dll
A first chance exception of type ‘System.Net.Sockets.SocketException’ occurred in Microsoft.SPOT.Net.dll
A first chance exception of type ‘System.Net.Sockets.SocketException’ occurred in Microsoft.SPOT.Net.dll
A first chance exception of type ‘System.Net.Sockets.SocketException’ occurred in Microsoft.SPOT.Net.dll
A first chance exception of type ‘uPLibrary.Networking.M2Mqtt.Exceptions.MqttCommunicationException’ occurred in M2Mqtt.NetMf.dll
An unhandled exception of type ‘uPLibrary.Networking.M2Mqtt.Exceptions.MqttCommunicationException’ occurred in M2Mqtt.NetMf.dll

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so my adapter initialization
Adapter = new EthernetENC28J60(GHI.Pins.FEZPandaIII.SpiBus.Spi1, GHI.Pins.FEZPandaIII.Gpio.D10, GHI.Pins.FEZPandaIII.Gpio.D9, GHI.Pins.FEZPandaIII.Gpio.D7);
should change to…?

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If you can ping your device then this is done correctly.

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And by ping I mean “ping 192.168…” from your command window.

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Gus,
So is it correct to say that if it responds to pings, then it is using .NetMF libraries and should work with the M2MQTT library?
Thank you for your help-

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@ w9ip - yes it should work. I do not understand why it would not.

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I finally got MQTT to work with the Fez Panda III. Had to insert
Thread.Sleep(4000);
before MQTTClient.Connect(). I guess the Fez has some thinking to do before it’s ready to connect. Anything less than 4 seconds fails. Go figure.
Thanks, Gus, for your patience.

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