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Arduino Forum MQTT client program not showing any results with Arduino
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Related

MQTT client program not showing any results with Arduino

Former Member
Former Member over 10 years ago

I modified the MQTT example present under MQTT library pubsubclient for Arduino.

My MQTT server address is 192.168.1.6 with port 8081.

To this MQTT server,another MQTT client in my mobile is able to connect.

But this is not working with Arduino.There is no error shown during compilation or during uploading.

Infact,I am not able to see the connection result messages such as "Connected" or "Not connected" which i given in Serial.println() in setup function.

I am resetting Arduino before uploading the program.Please let me know why this is not showing any output....

 

#include <SPI.h>

#include <Ethernet.h>

#include <PubSubClient.h>

// Update these with values suitable for your network.

byte mac[]    = {  0xDE, 0xED, 0xBA, 0xFE, 0xFE, 0xED };

byte server[] = {192, 168, 1, 6 };

//byte ip[]     = { 172, 16, 0, 100 };

 

 

void callback(char* topic, byte* payload, unsigned int length) {

  // handle message arrived

}

EthernetClient ethClient;

PubSubClient client(server, 8081, callback, ethClient);

void setup()

{

  Ethernet.begin(mac);

  if (client.connect("*")) {

     Serial.begin(9600);

    Serial.println("Connected to MQTT Server");

    client.publish("outTopic","hello world");

   // client.subscribe("inTopic");

  }

  else

  {

   Serial.println("Could not connect to MQTT Server");

  }

}

void loop()

{

  //client.loop();

 

}

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Top Replies

  • neilk
    neilk over 10 years ago in reply to Former Member +3
    generk4 and organtin Hi Radhamani and Giovanni - I had 30 minutes to spare so I copied the program from comment 19 and posted it into the Arduino IDE (I am using 1.6.1), compiled and uploaded it to a genuine…
  • Former Member
    Former Member over 10 years ago +3
    Hi Bob, Neil and Clem, I tried LM35 Temperature sensor with MQTT Arduino sketch and it works fine for me I am sooo happy Thanks once again for your wonderful support and help
  • Former Member
    Former Member over 10 years ago in reply to bobcroft +2
    Hi bob,Neil,Clem and many others who have helped and guided me in this issue, I have successfully completed MQTT program and Arduino is successfully publishing and subscribing messages Next step,I am going…
  • Former Member
    Former Member over 10 years ago in reply to organtin

    Yes sir...Its connected to  Binatone Wireless ADSL2+ Router.Thats the green colour wire (RJ45) shown in picture.RJ45 is working fine.I connected it separately to my PC from Router and verified Internet is working fine in LAN.

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  • organtin
    organtin over 10 years ago in reply to Former Member

    Ok, let me check something on my setup.

    I will not be able to do that until tomorrow.

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  • neilk
    neilk over 10 years ago in reply to Former Member

    generk4 and organtin Hi Radhamani and Giovanni - I had 30 minutes to spare so I copied the program from comment 19 and posted it into the Arduino IDE (I am using 1.6.1), compiled and uploaded it to a genuine Arduino UNO R2, fitted with a compatible Ethernet shield.(HanRun HR911105A 12/11) which carries a Wiznet chip.

     

    The Ethernet shield was connected to my Router with a standard Ethernet Cable.

     

    I was able to get the following:

    image

    So I think the problem must be with your setup, Radhamani.

     

    1. I didn't find it necessary to connect both the USB AND an external PSU to the Arduino. Not sure why you have been advised to do that.
    2. There is a bank of LEDs on the Ethernet shield....do they light up, proving that your shield is actually connected to your network?image

    Try pressing the RESET button if they don't light up; make sure the ICSP connector is properly pushed home; try a different Ethernet cable.

     

    Hope you get it working

     

    Neil

     

    Postscript - I was also able to telnet to it and get the elapsed time and reading

     

    Neil

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  • Former Member
    Former Member over 10 years ago in reply to neilk

    Hi Neil,

    Thanks for your update...

    Actually,the vendor technical person told that he didnt replace with new Ethernet Shield.Hence,i might be testing with old Ethernet shield only.

    The technical person who gave me the product told i have to connect External powersupply otherwise chip will shor-circuit and go off.He is asking me to pay another 1000 bugs to get new one... image Feeling like they are cheating ...

     

    In the Ethernet Shield,all the 4 lights are blinking.And,RJ45 cable is working fine.I tested by connecting the cable directly from Router to my PC in LAN and Internet is connected without  issues..

    As all the lights are glowing,not sure why Ethernet shield is still having problem in IP setup.

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  • neilk
    neilk over 10 years ago in reply to Former Member

    generk4  Hi Radhamani. Maybe the shield is faulty in some way. I can't think of anything else to suggest you try.

     

    Where are you in the world? How much is 1000 bugs in GBPounds or USDollars?

     

    Can you buy on eBay? There are lots of vendors  selling compatible Ethernet shields at reasonable prices, with genuine Arduino Shields costing more.

     

    Neil

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  • Former Member
    Former Member over 10 years ago in reply to neilk

    I am from India..Actually I am doing my college project and in only 2 more weeks I have to submit the project.And due to Ethernet shield issue,I am stuck with the project.Earlier I ordered in Ebay ,but they said they have ran out of stock.

    I am thatswhy trying to get the Shield directly from Electronics labs due to less time.

     

    I am planning to buy "PoEthernet Shield, cmostronics".Could you please suggest whether this component is right one for Arduino UNO?

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  • neilk
    neilk over 10 years ago in reply to Former Member

    generk4 Hi Radhamani.  As far as I can see it looks OK. The tutorial does use an Arduino UNO.

     

    Are you complicating things by going for POE, or is that part of your project?

     

    Neil

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  • Former Member
    Former Member over 10 years ago in reply to neilk

    Hi Neil Kenyon,Actually my project is to use a sensor to act as one of MQTT clients to communicate with IBM MessageSight which acts as MQTT Server to publish and subscribe messages.

    To achieve this scenario,I am using Ethernet shield to first gain an IP and then use similar setup as that of " A Simple Example (Arduino, MQTT, m2m.io) - m2mio " to achieve MQTT scenario.

    I am stuck up in the initial stage itself in setting up IP for Arduino due to issue in Ethernet shield configurations.

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  • neilk
    neilk over 10 years ago in reply to Former Member

    generk4  Hi Radhamani sorry I can't offer any more suggestions, other than a faulty Ethernet Shield.

     

    Hope you can get it sorted out

     

    Neil

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  • Former Member
    Former Member over 10 years ago in reply to neilk

    No problem Neil.Today I will be getting new Ethernet shield which will be working one.Then I will try the code and update.

    Thanks much for your help so far image

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