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--- amc2020:group_n:wifi [2020/07/29 10:46] – [3.3 Results] jonas001
+++ amc2020:group_n:wifi [2023/01/05 14:38] (current) – external edit 127.0.0.1
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 ====== ESP32 Connection to WiFi and MQTT ======
 ===== 1. About MQTT =====
-MQTT stands for Message Queuing Telemetry Transport and is publish-subscribe network protocol for transporting messages between different devices. It was first developed in 1999 and is very popular for IoT (Internet of Things) applications.
+MQTT stands for Message Queuing Telemetry Transport and is a publish-subscribe network protocol for transporting messages between different devices. It was first developed in 1999 and is very popular for IoT (Internet of Things) applications.
 The core of an MQTT network is a server also called MQTT broker. Other devices, called clients, can connect through WiFi to the broker and publish or subscribe to certain topics. The broker receives the messages that are published by the clients and sorts them by their topics. Clients can also subscribe to topics; if a new message is published under a certain topic, the broker redirects this message to all clients that are subscribed to that topic.
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       Timer= millis()+1000;
       Serial.print(".");
+      mqttClient.connect("ESP32Client");
     }
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         </li>
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-            For the ESP32, the password and the SSID of the local WiFi network need to be given as pointers of the type <b><font face="Courier New"><font style="color:#0098A3">const char</font></font></b>. The asterisks need to be replaced by the actual password and SSID.
+            The password and the SSID of the local WiFi network that the ESP32 connects to are defined here. The asterisks need to be replaced by the actual SSID/password for the sketch to work.
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-            The function <b><font face="Courier New">mqttClient.<font style="color:#CD5307">connect</font>()</font></b> establishes the connection with the broker. If the ESP32 is used, it needs <b><font face="Courier New"><font style="color:#008883">"ESP32Client"</font></font></b> as argument.
+            The function <b><font face="Courier New">mqttClient.<font style="color:#CD5307">connect</font>()</font></b> establishes the connection with the broker. If the ESP32 is used, <b><font face="Courier New"><font style="color:#008883">"ESP32Client"</font></font></b> is used as argument.
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 ^{{:amc2020:group_n:mqtttest_sensors.jpg?direct&800|Figure 4}}^
-|**//Figure 4//** Transmission of sensor data of DHT-22 and DS18B20 using MQTT.|
+|**//Figure 4//** Transmission of sensor data of DHT-22 and DS18B20 using MQTT. The left side shows the published measurement values in MQTT.fx; the right side shows the same results in the Arduino IDE's serial monitor.|
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