======== ESP32: Mesure de temperature ========

==== Liens Web ====

[[https://randomnerdtutorials.com/esp32-dht11-dht22-temperature-humidity-sensor-arduino-ide/| ESP32 : DHT11/22]]

[[https://randomnerdtutorials.com/esp32-dht11-dht22-temperature-humidity-web-server-arduino-ide/|ESP32 :  ServeurWeb1 DHT11/22]] 

[[https://microcontrollerslab.com/esp32-dht11-dht22-web-server/|ESP32 :  ServeurWeb2 DHT11/22]]

[[https://projetsdiy.fr/esp8266-dht22-mqtt-projet-objet-connecte/|ESP32 : Objet connecté DGT11/22]]

[[https://thingsboard.io/docs/samples/esp32/gpio-control-pico-kit-dht22-sensor/|ESP32 PicoKit : DHT22]]

[[https://github.com/bertmelis/esp32DHT|ESP32 : Librairie DHT22]]

[[https://lastminuteengineers.com/dht11-dht22-arduino-tutorial/|DHT11/22]]

[[https://roboindia.com/tutorials/DHT-sensor-arduino/|ARduino : DHT11/22]]





==== Test en réel sur carte ESP32 ====


=== Matériel ===


**ESP32 TTGO LORA 32 V2.0**

[[https://github.com/LilyGO/TTGO-LORA32|Caracteristiques ESP32 TTGO LORA 32 V2.0]]

{{ :start:arduino:esp32:htb1v_abbtni8kjjsszbq6z4kfxah.resized.jpg?direct&400 |}}

** DHT 22 **

[[https://www.didel.com/DHT22.pdf|Caractéristiques DHT22 PDF FR]]

{{ :start:arduino:esp32:dht22-pinout-800x800.jpg?direct&300 |}}

{{ :start:arduino:esp32:capture_du_2021-03-16_12-38-57.png?direct&600 |}}




=== Branchement ===

ESP32 Lora32 V2 + DHT22

{{ :start:arduino:esp32:capture_du_2021-03-16_12-21-43.jpg?direct&400 |}}


=== Librairies à installer===

** DHT **
[[https://github.com/adafruit/DHT-sensor-library| DHT-sensor-Library]]


**ESPAsyncWebServer**
[[https://github.com/me-no-dev/ESPAsyncWebServer|ESPAsyncWebServer.zip]]

**AsyncTCP**
[[https://github.com/me-no-dev/AsyncTCP|AsyncTCP.zip]]

**Adafruit_Sensor**
[[https://github.com/adafruit/Adafruit_Sensor|Adafruit_Sensor.zip]]




=== Programmes ===

<code c ESP32_Temperature_serveur_Web.ino>


/*********
  Rui Santos
  Complete project details at https://randomnerdtutorials.com  
*********/

// Import required libraries
#include "WiFi.h"
#include "ESPAsyncWebServer.h"
#include <Adafruit_Sensor.h>
#include <DHT.h>

// Replace with your network credentials
const char* ssid = "xxxxxxxxxxxx";
const char* password = "xxxxxxxxxxxxxx";

#define DHTPIN 13    // 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);

// Create AsyncWebServer object on port 80
AsyncWebServer server(80);

String readDHTTemperature() {
  // Sensor readings may also be up to 2 seconds 'old' (its a very slow sensor)
  // Read temperature as Celsius (the default)
  float t = dht.readTemperature();
  // Read temperature as Fahrenheit (isFahrenheit = true)
  //float t = dht.readTemperature(true);
  // Check if any reads failed and exit early (to try again).
  if (isnan(t)) {    
    Serial.println("Failed to read from DHT sensor!");
    return "--";
  }
  else {
    Serial.println(t);
    return String(t);
  }
}

String readDHTHumidity() {
  // Sensor readings may also be up to 2 seconds 'old' (its a very slow sensor)
  float h = dht.readHumidity();
  if (isnan(h)) {
    Serial.println("Failed to read from DHT sensor!");
    return "--";
  }
  else {
    Serial.println(h);
    return String(h);
  }
}

const char index_html[] PROGMEM = R"rawliteral(
<!DOCTYPE HTML><html>
<head>
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.7.2/css/all.css" integrity="sha384-fnmOCqbTlWIlj8LyTjo7mOUStjsKC4pOpQbqyi7RrhN7udi9RwhKkMHpvLbHG9Sr" crossorigin="anonymous">
  <style>
    html {
     font-family: Arial;
     display: inline-block;
     margin: 0px auto;
     text-align: center;
    }
    h2 { font-size: 3.0rem; }
    p { font-size: 3.0rem; }
    .units { font-size: 1.2rem; }
    .dht-labels{
      font-size: 1.5rem;
      vertical-align:middle;
      padding-bottom: 15px;
    }
  </style>
</head>
<body>
  <h2>ESP32 Serveur DHT 22</h2>
  <p>
    <i class="fas fa-thermometer-half" style="color:#059e8a;"></i> 
    <span class="dht-labels">Temperature</span> 
    <span id="temperature">%TEMPERATURE%</span>
    <sup class="units">&deg;C</sup>
  </p>
  <p>
    <i class="fas fa-tint" style="color:#00add6;"></i> 
    <span class="dht-labels">Humidite</span>
    <span id="humidity">%HUMIDITY%</span>
    <sup class="units">&percnt;</sup>
  </p>
</body>
<script>
setInterval(function ( ) {
  var xhttp = new XMLHttpRequest();
  xhttp.onreadystatechange = function() {
    if (this.readyState == 4 && this.status == 200) {
      document.getElementById("temperature").innerHTML = this.responseText;
    }
  };
  xhttp.open("GET", "/temperature", true);
  xhttp.send();
}, 10000 ) ;

setInterval(function ( ) {
  var xhttp = new XMLHttpRequest();
  xhttp.onreadystatechange = function() {
    if (this.readyState == 4 && this.status == 200) {
      document.getElementById("humidity").innerHTML = this.responseText;
    }
  };
  xhttp.open("GET", "/humidity", true);
  xhttp.send();
}, 10000 ) ;
</script>
</html>)rawliteral";

// Replaces placeholder with DHT values
String processor(const String& var){
  //Serial.println(var);
  if(var == "TEMPERATURE"){
    return readDHTTemperature();
  }
  else if(var == "HUMIDITY"){
    return readDHTHumidity();
  }
  return String();
}

void setup(){
  // Serial port for debugging purposes
  Serial.begin(115200);

  dht.begin();
  
  // Connect to Wi-Fi
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi..");
  }

  // Print ESP32 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", readDHTTemperature().c_str());
  });
  server.on("/humidity", HTTP_GET, [](AsyncWebServerRequest *request){
    request->send_P(200, "text/plain", readDHTHumidity().c_str());
  });

  // Start server
  server.begin();
}
 
void loop(){
  
}

</code>


=== Ecran serveur web ===

{{ :start:arduino:esp32:capture_du_2021-03-16_12-45-05.png?direct&600 |}}





 