ESP8266 Web Server

Je vais décrire dans cet article comment piloter une carte 4 relais depuis votre navigateur ou votre smartphone.

A noter que je me suis fortement inspiré de cet article pour mener à bien cette réalisation.

Le cœur du montage est un NODEMCU.

 
Celui-ci embarque un micro contrôleur wifi ESP8266.
Pour pouvoir le programmer on utilisera l’ IDE Arduino ce qui nécessitera quelques manipulations décrites par exemple dans cet article.
Nota: Si vous saisissez “ESP8266 arduino” dans votre moteur de recherche vous obtiendrez en retour une quantité très importante d’articles décrivant cette manipulation …

 
Code à injecter dans le NODEMCU:

/*********
  Rui Santos
  Complete project details at http://randomnerdtutorials.com
*********/
// Load Wi-Fi library
#include <ESP8266WiFi.h>
// Replace with your network credentials
const char* ssid     = "mabox";
const char* password = "123456789";
// Set web server port number to 80
WiFiServer server(80);
// Variable to store the HTTP request
String header;
// Auxiliar variables to store the current output state
String output5State = "off";
String output4State = "off";
String output14State = "off";
String output12State = "off";
//Variables gestion compteur
int Etat_D8; //variable qui enregistre l'état de l' entrée D8
boolean memoire=0; //Bit mémoire qui servira à occulter les rebonds sur l'entrée D8
long cpt = 0; //compteur d'impulsions
// Assign output variables to GPIO pins
const int output5 = 5; //GPIO5 - D1 - Relais 1
const int output4 = 4; //GPIO4 - D2 - Relais 2
const int output14 = 14; //GPIO14 - D5 - Relais 3
const int output12 = 12; //GPIO12 - D6 - Relais 4
int impulsion = 15; //GPIO15 - D8 - Compteur WATTS
long variable = 0;
void setup() {
  Serial.begin(115200);
  // Initialize the output variables as outputs
  pinMode(output5, OUTPUT);
  pinMode(output4, OUTPUT);
  pinMode(output14, OUTPUT);
  pinMode(output12, OUTPUT);
  pinMode(impulsion, INPUT);
  // Set outputs to LOW
  digitalWrite(output5, LOW);
  digitalWrite(output4, LOW);
  digitalWrite(output14, LOW);
  digitalWrite(output12, LOW);
  // Connect to Wi-Fi network with SSID and password
  Serial.print("Connecting to ");
  Serial.println(ssid);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  // Print local IP address and start web server
  Serial.println("");
  Serial.println("WiFi connected.");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());
  server.begin();
}
void loop(){
  WiFiClient client = server.available();   // Listen for incoming clients
  if (client) {                             // If a new client connects,
    Serial.println("New Client.");          // print a message out in the serial port
    String currentLine = "";                // make a String to hold incoming data from the client
    while (client.connected()) {            // loop while the client's connected
        //Gestion compteur d'impulsions
                Etat_D8 = digitalRead(impulsion);
                if (Etat_D8 == LOW && memoire == 0)
                {
                cpt ++;
                memoire =1;
                Serial.print("Etat entrée D8: ");
                Serial.println(Etat_D8);
                Serial.print("Etat du compteur: ");
                Serial.println(cpt);
                }
                if (Etat_D8 == HIGH)
                {
                  memoire =0;
                }
      if (client.available()) {             // if there's bytes to read from the client,
        char c = client.read();             // read a byte, then
        Serial.write(c);                    // print it out the serial monitor
        header += c;
        if (c == '\n') {                    // if the byte is a newline character
          // if the current line is blank, you got two newline characters in a row.
          // that's the end of the client HTTP request, so send a response:
          if (currentLine.length() == 0) {
            // HTTP headers always start with a response code (e.g. HTTP/1.1 200 OK)
            // and a content-type so the client knows what's coming, then a blank line:
            client.println("HTTP/1.1 200 OK");
            client.println("Content-type:text/html");
            client.println("Connection: close");
            client.println();
          // turns the GPIOs on and off
            if (header.indexOf("GET /5/on") >= 0) {
              Serial.println("GPIO 5 on");
              output5State = "on";
              digitalWrite(output5, HIGH);
            }
            else if (header.indexOf("GET /5/off") >= 0) {
              Serial.println("GPIO 5 off");
              output5State = "off";
              digitalWrite(output5, LOW);
            }
            else if (header.indexOf("GET /4/on") >= 0) {
              Serial.println("GPIO 4 on");
              output4State = "on";
              digitalWrite(output4, HIGH);
            }
            else if (header.indexOf("GET /4/off") >= 0) {
              Serial.println("GPIO 4 off");
              output4State = "off";
              digitalWrite(output4, LOW);
            }
            else if (header.indexOf("GET /14/on") >= 0) {
              Serial.println("GPIO 14 on");
              output14State = "on";
              digitalWrite(output14, HIGH);
            }
            else if (header.indexOf("GET /14/off") >= 0) {
              Serial.println("GPIO 14 off");
              output14State = "off";
              digitalWrite(output14, LOW);
            }
            else if (header.indexOf("GET /12/on") >= 0) {
              Serial.println("GPIO 12 on");
              output12State = "on";
              digitalWrite(output12, HIGH);
            }
            else if (header.indexOf("GET /12/off") >= 0) {
              Serial.println("GPIO 12 off");
              output12State = "off";
              digitalWrite(output12, LOW);
            }
            // Display the HTML web page
            client.println("<!DOCTYPE html><html>");
            client.println("<head><meta name=\"viewport\" content=\"width=device-width, initial-scale=1\">");
            client.println("<link rel=\"icon\" href=\"data:,\">");
            // CSS to style the on/off buttons
            // Feel free to change the background-color and font-size attributes to fit your preferences
            client.println("<style>html { font-family: Helvetica; display: inline-block; margin: 0px auto; text-align: center;}");
            client.println(".button { background-color: #195B6A; border: none; color: white; padding: 16px 40px;");
            client.println("text-decoration: none; font-size: 30px; margin: 2px; cursor: pointer;}");
            client.println(".button2 {background-color: #77878A;}</style></head>");
            // Web Page Heading
            client.println("<body><h1>Kergoaler - WEB Relay Server</h1>");
            //Affichage compteur
            client.println("<p>Etat Compteur " + String(cpt) + "</p>");
            // Display current state, and ON/OFF buttons for GPIO 5
            client.println("<p>GPIO 5 - State " + output5State + "</p>");
            // If the output5State is off, it displays the ON button
            if (output5State=="off") {
              client.println("<p><a href=\"/5/on\"><button class=\"button\">ON</button></a></p>");
            } else {
              client.println("<p><a href=\"/5/off\"><button class=\"button button2\">OFF</button></a></p>");
            }
            // Display current state, and ON/OFF buttons for GPIO 4
            client.println("<p>GPIO 4 - State " + output4State + "</p>");
            // If the output4State is off, it displays the ON button
            if (output4State=="off") {
              client.println("<p><a href=\"/4/on\"><button class=\"button\">ON</button></a></p>");
            } else {
              client.println("<p><a href=\"/4/off\"><button class=\"button button2\">OFF</button></a></p>");
            }
            client.println("</body></html>");
             // Display current state, and ON/OFF buttons for GPIO 14
            client.println("<p>GPIO 14 - State " + output14State + "</p>");
            // If the output14State is off, it displays the ON button
            if (output14State=="off") {
              client.println("<p><a href=\"/14/on\"><button class=\"button\">ON</button></a></p>");
            } else {
              client.println("<p><a href=\"/14/off\"><button class=\"button button2\">OFF</button></a></p>");
            }
            client.println("</body></html>");
             // Display current state, and ON/OFF buttons for GPIO 12
            client.println("<p>GPIO 12 - State " + output12State + "</p>");
            // If the output12State is off, it displays the ON button
            if (output12State=="off") {
              client.println("<p><a href=\"/12/on\"><button class=\"button\">ON</button></a></p>");
            } else {
              client.println("<p><a href=\"/12/off\"><button class=\"button button2\">OFF</button></a></p>");
            }
            client.println("</body></html>");
            // The HTTP response ends with another blank line
            client.println();
            // Break out of the while loop
            break;
          } else { // if you got a newline, then clear currentLine
            currentLine = "";
          }
        } else if (c != '\r') {  // if you got anything else but a carriage return character,
          currentLine += c;      // add it to the end of the currentLine
        }
      }
    }
    // Clear the header variable
    header = "";
    // Close the connection
    client.stop();
    Serial.println("Client disconnected.");
    Serial.println("");
  }
}

Schéma électrique:

 
Liste du matériel (Aliexpress)

Libellé  TTC  Observations
Nodemcu             2.22 €
CD 4011             2.33 € 10 Unités
module relais 4 canaux             1.49 €
Plaque FR4 fibre de verre 6×14 cm             1.69 €
Alimentation 220Vac – 5V700mA (3.5 w)             0.81 €
            8.54 €

 

dav