b9cZx5nS

1#include <WiFi.h>
2#include <PubSubClient.h>
3
4const char* ssid = "Wokwi-GUEST";
5const char* password = "";
6const char* mqtt_server = "test.mosquitto.org";
7const char* topic_temp = "DHT22/suhu";
8const char* topic_hum = "DHT22/kelembapan";
9
10WiFiClient espClient;
11PubSubClient client(espClient);
12
13void setup_wifi() 
14{
15  Serial.println();
16  Serial.print("Connecting to ");
17  Serial.println(ssid);
18
19  WiFi.mode(WIFI_STA);
20  WiFi.begin(ssid, password);
21
22  while (WiFi.status() != WL_CONNECTED) 
23  {
24    delay(500);
25    Serial.print(".");
26  }
27
28  Serial.println("");
29  Serial.println("WiFi connected");
30  Serial.println("IP address: ");
31  Serial.println(WiFi.localIP());
32}
33
34void callback(char* topic, byte* payload, unsigned int length) 
35{
36  Serial.print("Message arrived in topic: ");
37  Serial.println(topic);
38 
39  Serial.print("Message:");
40  for (int i = 0; i < length; i++) 
41  {
42    Serial.print((char)payload[i]);
43  }
44 
45  Serial.println();
46  Serial.println("-----------------------");
47}
48
49void reconnect() 
50{
51  while (!client.connected()) 
52  {
53    Serial.print("Attempting MQTT connection...");
54    // Create a random client ID
55    String clientId = "mqtt-explorer-584bcd18";
56    clientId += String(random(0xffff), HEX);
57    // Attempt to connect
58    if (client.connect(clientId.c_str())) 
59    {
60      Serial.println("Connected");
61      client.subscribe(topic_temp);
62      client.subscribe(topic_hum);
63    } 
64    else 
65    {
66      Serial.print("failed, rc=");
67      Serial.print(client.state());
68      Serial.println(" try again in 5 seconds");
69      // Wait 5 seconds before retrying
70      delay(5000);
71    }
72  }
73}
74
75void setup() 
76{
77  Serial.begin(115200);
78    setup_wifi();
79  client.setServer(mqtt_server, 1883);
80  client.setCallback(callback);  
81}
82
83void loop() 
84{
85
86  if (!client.connected()) 
87  {
88    reconnect();
89  }
90  client.loop();
91}