AHT15-MQTT

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#include <Wire.h>
#include <PubSubClient.h> //請先安裝PubSubClient程式庫
#include <WiFi.h>
// ------ 以下修改成你自己的WiFi帳號密碼 ------
char* ssid = "SSID";
char* password = "SSIDpassword";
char* MQTTServer = "mqttgo.io";//免註冊MQTT伺服器
int MQTTPort = 1883;//MQTT Port
char* MQTTUser = "";//不須帳密
char* MQTTPassword = "";//不須帳密
//推播主題1:推播溫度(記得改Topic)
char* MQTTPubTopic1 = "Topic/room/溫度";
//推播主題2:推播濕度(記得改Topic)
char* MQTTPubTopic2 = "Topic/room/濕度";
WiFiClient WifiClient;
PubSubClient MQTTClient(WifiClient);

#define AHT15_ADDRESS 0x38
#define AHT15_RESET 0xBA
#define AHT15_INIT 0xBE
#define AHT15_START_MEASUREMENT 0xAC

void setup() {
  Wire.begin();
  Serial.begin(115200);
 
 //開始WiFi連線
  WifiConnecte();

  //開始MQTT連線
  MQTTConnecte();

  // Reset sensor
  Wire.beginTransmission(AHT15_ADDRESS);
  Wire.write(AHT15_RESET);
  Wire.endTransmission();
  delay(20);
  
  // Initialize sensor
  Wire.beginTransmission(AHT15_ADDRESS);
  Wire.write(AHT15_INIT);
  Wire.write(0x08);
  Wire.write(0x00);
  Wire.endTransmission();
  delay(10);
}

void loop() {

  //如果WiFi連線中斷，則重啟WiFi連線
  if (WiFi.status() != WL_CONNECTED) {
    WifiConnecte();
  }

  //如果MQTT連線中斷，則重啟MQTT連線
  if (!MQTTClient.connected()) {
    MQTTConnecte();
  }

  // Start measurement
  Wire.beginTransmission(AHT15_ADDRESS);
  Wire.write(AHT15_START_MEASUREMENT);
  Wire.write(0x33);
  Wire.write(0x00);
  Wire.endTransmission();
  delay(80);
  
  // Read data
  Wire.requestFrom(AHT15_ADDRESS, 6);
  uint8_t data[6];
  for (int i = 0; i < 6; i++) {
    data[i] = Wire.read();
  }
  
  // Calculate humidity and temperature
  uint32_t rawHumidity = ((uint32_t)data[1] << 12) | ((uint32_t)data[2] << 4) | (data[3] >> 4);
  float humidity = rawHumidity * 100.0 / (1 << 20);
  
  uint32_t rawTemperature = (((uint32_t)data[3] & 0xF) << 16) | ((uint32_t)data[4] << 8) | data[5];
  float temperature = ((200.0 * rawTemperature) / (1 << 20)) - 50;
  
   MQTTClient.publish(MQTTPubTopic1, String(temperature).c_str());
  MQTTClient.publish(MQTTPubTopic2, String(humidity).c_str());
  Serial.print("溫度:");
  Serial.print(temperature);
  Serial.print("℃, 濕度:");
  Serial.print(humidity);
  Serial.println("%");
  Serial.println("溫溼度已推播到MQTT Broker");

  delay(10000);
 
}

//開始WiFi連線
void WifiConnecte() {
  //開始WiFi連線
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("WiFi連線成功");
  Serial.print("IP Address:");
  Serial.println(WiFi.localIP());
}

//開始MQTT連線
void MQTTConnecte() {
  MQTTClient.setServer(MQTTServer, MQTTPort);
  while (!MQTTClient.connected()) {
    //以亂數為ClietID
    String  MQTTClientid = "esp32-" + String(random(1000000, 9999999));
    if (MQTTClient.connect(MQTTClientid.c_str(), MQTTUser, MQTTPassword)) {
      //連結成功，顯示「已連線」。
      Serial.println("MQTT已連線");
    } else {
      //若連線不成功，則顯示錯誤訊息，並重新連線
      Serial.print("MQTT連線失敗,狀態碼=");
      Serial.println(MQTTClient.state());
      Serial.println("五秒後重新連線");
      delay(5000);
    }
  }
}