Esp32 and MQTT (Raspberry pi) connection issue

[bilal_93]

Hello, I am trying to connect Esp32 to MQTT broker(Raspberry Pi) via Wi-Fi but I am facing issues. I am trying to send "Hello" from Esp32 to MQTT. Upon checking, Esp32 IP Address is: "192.168.0.105", Raspberry Pi IP: "192.169.0.106" and Wi-Fi IP is: "192.168.0.1". I don't know if this is the issue or something else. I am also posting the code below, kindly tell me what am I doing wrong or how can I solve this issue? Thank you.

Code: [Select all] [Expand/Collapse]

1. [code]
2. #include <HardwareSerial.h>
3. #include <PubSubClient.h> //Connect and publish data to the MQTT broker
4. #include <WiFi.h> //Enables Esp32 to connect to the local network(via WiFi)
5. #define RXD2 16
6. #define TXD2 17
7. //char myRcvChar;
8. //WiFi
9. const char* ssid = "Bilal-Asad-310";
10. const char* wifi_password = "31019309";
11. //MQTT
12. const char* mqtt_server = "192.168.0.106";
13. const char* message_topic = "test/esp32/message";
14. //const char* bending_topic = "exoskeleton/walking/bending";
15. //const char* streching_topic = "exoskeleton/walking/streching";
16. const char* mqtt_username = "pi"; //MQTT username
17. const char* mqtt_password = "raspberry"; //MQTT password
18. const char* clientID = "first message";
19.  
20. //Initialise the Wifi and MQTT Client objects
21. WiFiClient wifiClient;
22. //1883 is the listener port for the broker
23. PubSubClient client(mqtt_server,1883,wifiClient);
24.  
25.  
26. //Custom function to connect to the MQTT broker via WiFi
27. void connect_MQTT(){
28.   Serial.print("Connecting to ");
29.   Serial.println(ssid);
30.  
31.   //Connect to the WiFi
32.   WiFi.begin(ssid, wifi_password);
33.  
34.   //wait until the connection has been confirmed before continuing
35.   while(WiFi.status()!= WL_CONNECTED){
36.     delay(500);
37.     Serial.print(".");
38.   }
39.   //Debugging-Output the IP Address of the ESP32
40.   Serial.println("WiFi connected");
41.   Serial.println("IP Address");
42.   Serial.println(WiFi.localIP());
43.  
44.   //Connect to MQTT Broker
45.   //client.connect returns a boolean value to let us know if the connection was successful
46.   //if the connection is failing, make sure you are using the correct MQTT Username and Password
47.   if(client.connect(clientID,mqtt_username,mqtt_password)){
48.     Serial.println("Connected to MQTT Broker");
49.   }
50.   else{
51.     Serial.println("Connection to MQTT Broker failed...");
52.   }
53. }
54.  
55. void setup() {
56.   // put your setup code here, to run once:
57.   Serial.begin(115200);
58.   Serial2.begin(115200, SERIAL_8N1, RXD2, TXD2);
59.  //char myRcvchar;
60.  
61.  
62. }
63.  
64. void loop() {
65.   // put your main code here, to run repeatedly:
66.   connect_MQTT();
67.   Serial.setTimeout(2000);
68.   Serial.println("Data Received: ");
69.   Serial.println(Serial2.readStringUntil('\n'));
70.  
71.   const char* message = "Hello";
72.   Serial.print("Message Received: ");
73.   Serial.print(message);
74.   //MQTT can only transmit strings
75.   String ms = "Mess: "+String((char*)message);
76.  
77.   //Publish to MQTT broker
78.   if(client.publish(message_topic, String(message).c_str())){
79.     Serial.println("Message sent");
80.   }
81. //Again client.publish will return boolean value depending on whether it succeded or not.
82. //if the message failed to send, try again, as the connection might have broken
83. else{
84.   Serial.println("Message failed to send. Reconnecting to MQTT Broker and trying again");
85.   client.connect(clientID,mqtt_username,mqtt_password);
86.   delay(10); //This delay ensures that client.publish does not clash with client.connect call
87.   client.publish(message_topic,String(message).c_str());
88. }
89. client.disconnect(); //disconnect from the MQTT broker
90. delay(1000*60); //print new values every 2 minutes
91.  
92.  
93. }
94. [/code]

GeSHi © Codebox Plus Extension