/********* Rui Santos Complete project details at https://randomnerdtutorials.com/esp8266-dht11dht22-temperature-and-humidity-web-server-with-arduino-ide/ *********/ // Import required libraries #include #include #include #include #include #include #include // Replace with your network credentials const char* ssid = "REPLACE_WITH_YOUR_SSID"; const char* password = "REPLACE_WITH_YOUR_PASSWORD"; #define DHTPIN 5 // Digital pin connected to the DHT sensor // Uncomment the type of sensor in use: //#define DHTTYPE DHT11 // DHT 11 #define DHTTYPE DHT22 // DHT 22 (AM2302) //#define DHTTYPE DHT21 // DHT 21 (AM2301) DHT dht(DHTPIN, DHTTYPE); // current temperature & humidity, updated in loop() float t = 0.0; float h = 0.0; // Create AsyncWebServer object on port 80 AsyncWebServer server(80); // Generally, you should use "unsigned long" for variables that hold time // The value will quickly become too large for an int to store unsigned long previousMillis = 0; // will store last time DHT was updated // Updates DHT readings every 10 seconds const long interval = 10000; const char index_html[] PROGMEM = R"rawliteral(

ESP8266 DHT Server

Temperature %TEMPERATURE% ^°C

Humidity %HUMIDITY% ^%

)rawliteral"; // Replaces placeholder with DHT values String processor(const String& var){ //Serial.println(var); if(var == "TEMPERATURE"){ return String(t); } else if(var == "HUMIDITY"){ return String(h); } return String(); } void setup(){ // Serial port for debugging purposes Serial.begin(115200); dht.begin(); // Connect to Wi-Fi WiFi.begin(ssid, password); Serial.println("Connecting to WiFi"); while (WiFi.status() != WL_CONNECTED) { delay(1000); Serial.println("."); } // Print ESP8266 Local IP Address Serial.println(WiFi.localIP()); // Route for root / web page server.on("/", HTTP_GET, [](AsyncWebServerRequest *request){ request->send_P(200, "text/html", index_html, processor); }); server.on("/temperature", HTTP_GET, [](AsyncWebServerRequest *request){ request->send_P(200, "text/plain", String(t).c_str()); }); server.on("/humidity", HTTP_GET, [](AsyncWebServerRequest *request){ request->send_P(200, "text/plain", String(h).c_str()); }); // Start server server.begin(); } void loop(){ unsigned long currentMillis = millis(); if (currentMillis - previousMillis >= interval) { // save the last time you updated the DHT values previousMillis = currentMillis; // Read temperature as Celsius (the default) float newT = dht.readTemperature(); // Read temperature as Fahrenheit (isFahrenheit = true) //float newT = dht.readTemperature(true); // if temperature read failed, don't change t value if (isnan(newT)) { Serial.println("Failed to read from DHT sensor!"); } else { t = newT; Serial.println(t); } // Read Humidity float newH = dht.readHumidity(); // if humidity read failed, don't change h value if (isnan(newH)) { Serial.println("Failed to read from DHT sensor!"); } else { h = newH; Serial.println(h); } } }