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#include <WiFi.h>

#include <PubSubClient.h>

#include <DHT11.h>

DHT11 dht11(2);

const char* ssid = "your wifi ssid";
const char* password = "your wifi password";
//Mqtt服务器
const char* mqtt_server = "test.mosquitto.org";

WiFiClient espClient;
//创建MQTT客户端对象
PubSubClient client(espClient);
//上一次发送数据的时间戳
long lastMsg = 0;
char msg[50]; //发送的消息字符串
int value = 0;  //待发送数据
int temperature = 0; //温度
int humidity = 0; //湿度

void setup() {
  // put your setup code here, to run once:
  //初始化串口通信
  Serial.begin(115200);
  //配置wifi连接
  setup_wifi();
  //配置mqtt服务器
  client.setServer(mqtt_server,1883);
  
}

void setup_wifi() {
  delay(10);
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(ssid);
  //连接wifi网络
  WiFi.begin(ssid,password);
  while(WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.println("WiFi connected");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());
}

void reconnect() {
  //循环尝试mqtt连接
  while(!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    //String clientId = "ESP32Client-";
    //clientId += String(random(0xffff), HEX);
  //尝试连接mqtt服务器
    if(client.connect("esp32c3_Telemetry")) {
      Serial.println("connected");
      //client.subscribe("esp32c3_Telemetry/temp");  //订阅主题
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      delay(5000);
    }
  }
}

void loop() {  
  // put your main code here, to run repeatedly:
  //如果MQTT客户端没有连接
  if(!client.connected()) {
    reconnect();
  }
  //MQTT客户端保持连接
  client.loop();
  //获取当前时间
  long now = millis();
  //存储温湿度值的数组
  //float temp_hum_val[2] = {0};
  //如果当前时间与上次消息发送时间间隔超过5s
  if(now - lastMsg > 5000) {
    //更新上次发送消息时间
    lastMsg = now;
    //获取温湿度值
    int result = dht11.readTemperatureHumidity(temperature, humidity);

    //温度值转化为字符串缓冲区
    char tempString[8];
    dtostrf(temperature,1,2,tempString);    
    Serial.print("Temerature: ");
    Serial.println(tempString);    //打印温度字符
    //String temp= tempString +" °C";
    client.publish("esp32c3_Telemetry/Temperaturedataread",tempString); //发布mqtt温度数据

    //湿度值转化为字符串缓冲区
    char humString[8];
    dtostrf(humidity,1,2,humString);    
    Serial.print("Humidity: ");
    Serial.println(humString);    //打印温度字符
    //String hum = humString +" %";
    client.publish("esp32c3_Telemetry/Humiditydataread",humString); //发布mqtt温度数据

  }
}