ESP32 WITH WEB SERVER

Pada percobaan kali ini, dijelaskan mengenai pembuatan web server dalam ESP32. Percobaan ini menggunakan sensor eksternal. Sensor eksternal yang digunakan merupakan sensor BMP180. Hasil pembacaan sensor akan ditampilkan pada web browser.

Pada percobaan ini, komponen dan perangkat yang dibutuhkan sebagai berikut.

1. ESP32 DEVKIT V1 Board (yang saya gunakan 30 pin)

2. Arduino IDE

3. Kabel USB type A to micro USB

4. PC / Laptop

6. Jumper wires (yang saya gunakan female to male) sebanyak 4 buah

7. Sensor BMP180

8. Breadboard

Langkah - langkah pengerjaan :

Pertama, merangkai komponen sesuai skema berikut

Keterangan :

1. GPIO GND menuju GND BMP180

2. GPIO 3V3 menuju VCC BMP180

3. GPIO D21 menuju SDA BMP180

4. GPIO D22 menuju SCL BMP180

Kedua, masukkan code program berikut pada Arduino IDE.

// Load Wi-Fi library
#include <WiFi.h>
#include <Wire.h>
#include <Adafruit_BMP085.h>
#include <Adafruit_Sensor.h>

//uncomment the following lines if you're using SPI
/*#include <SPI.h>
#define BME_SCK 18
#define BME_MISO 19
#define BME_MOSI 23
#define BME_CS 5*/

Adafruit_BMP085 bmp;

// Replace with your network credentials
const char* ssid     = "iPhone";
const char* password = "abesarkkecilukecil";

// Set web server port number to 80
WiFiServer server(80);

// Variable to store the HTTP request
String header;

// Current time
unsigned long currentTime = millis();
// Previous time
unsigned long previousTime = 0; 
// Define timeout time in milliseconds (example: 2000ms = 2s)
const long timeoutTime = 2000;

void setup() {
  Serial.begin(115200);
  bool status;

  // default settings
  // (you can also pass in a Wire library object like &Wire2)
  //status = bmp.begin();  
  if (!bmp.begin()) {
  Serial.println("Could not find a valid BMP085/BMP180 sensor, check wiring!");
  while (1) {}
  }

  // 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,
    currentTime = millis();
    previousTime = currentTime;
    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() && currentTime - previousTime <= timeoutTime) {  // loop while the client's connected
      currentTime = millis();
      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();
            
            // 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 table 
            client.println("<style>body { text-align: center; font-family: \"Trebuchet MS\", Arial;}");
            client.println("table { border-collapse: collapse; width:35%; margin-left:auto; margin-right:auto; }");
            client.println("th { padding: 12px; background-color: #0043af; color: white; }");
            client.println("tr { border: 1px solid #ddd; padding: 12px; }");
            client.println("tr:hover { background-color: #bcbcbc; }");
            client.println("td { border: none; padding: 12px; }");
            client.println(".sensor { color:white; font-weight: bold; background-color: #bcbcbc; padding: 1px; }");
            
            // Web Page Heading
            client.println("</style></head><body><h1>ESP32 with BMP180</h1>");
            client.println("<table><tr><th>MEASUREMENT</th><th>VALUE</th></tr>");
            client.println("<tr><td>Temp. Celcius</td><td><span class=\"sensor\">");
            client.println(bmp.readTemperature());
            client.println(" *C</span></td></tr>");  
            client.println("<tr><td>Temp. Fahrenheit</td><td><span class=\"sensor\">");
            client.println(1.8 * bmp.readTemperature() + 32);
            client.println(" *F</span></td></tr>");       
            client.println("<tr><td>Pressure</td><td><span class=\"sensor\">");
            client.println(bmp.readPressure() / 100.0F);
            client.println(" Pa</span></td></tr>");
            client.println("<tr><td>Altitude</td><td><span class=\"sensor\">");
            client.println(bmp.readAltitude());
            client.println(" m</span></td></tr>"); 
            client.println("<tr><td>Pressure at sealevel (calculated)</td><td><span class=\"sensor\">");
            client.println(bmp.readSealevelPressure());
            client.println(" Pa</span></td></tr>");
            client.println("<tr><td>Real altitude</td><td><span class=\"sensor\">");
            client.println(bmp.readAltitude(102000));
            client.println(" m</span></td></tr>");
            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("");
  }
}

Penjelasan code program :

1. Memasukkan library yang diperlukan.

#include <WiFi.h>
#include <Wire.h>
#include <Adafruit_BMP085.h>
#include <Adafruit_Sensor.h>

2. Memasukkan SPI Communication karena menggunakan komunikasi I2C berupa BMP180.

#define BME_SCK 18
#define BME_MISO 19
#define BME_MOSI 23
#define BME_CS 5*/

3. Memasukkan SSID dan password di baris berikut di dalam tanda kutip ganda.

const char* ssid     = "iPhone";
const char* password = "abesarkkecilukecil";

4. Mengatur web server ke port 80.

WiFiServer server(80);

5. Membuat variabel untuk menyimpan header permintaan HTTP.

String header;

Setup()

6. Memulai komunikasi serial dengan baud rate 115200 untuk keperluan debugging.

Serial.begin(115200);

7. Memeriksa bahwa sensor BME280 berhasil diinisialisasi

 if (!bmp.begin()) {
  Serial.println("Could not find a valid BMP085/BMP180 sensor, check wiring!");
  while (1) {}
  }

8. Memulai koneksi Wi-Fi dengan WiFi.begin(ssid, password); tunggu koneksi berhasil dan mencetak alamat IP di Serial Monitor.

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();

Loop()

9. ESP32 selalu mendengarkan klien masuk

WiFiClient client = server.available();

10. Saat permintaan diterima klien, maka akan menyimpan data yang masuk. Loop sementara akan berjalan selama klien tetap terhubung.

if (client) {                             // If a new client connects,
    currentTime = millis();
    previousTime = currentTime;
    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() && currentTime - previousTime <= timeoutTime) {  // loop while the client's connected
      currentTime = millis();
      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();

11. Menampilkan halaman web HTML.

// 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 table 
            client.println("<style>body { text-align: center; font-family: \"Trebuchet MS\", Arial;}");
            client.println("table { border-collapse: collapse; width:35%; margin-left:auto; margin-right:auto; }");
            client.println("th { padding: 12px; background-color: #0043af; color: white; }");
            client.println("tr { border: 1px solid #ddd; padding: 12px; }");
            client.println("tr:hover { background-color: #bcbcbc; }");
            client.println("td { border: none; padding: 12px; }");
            client.println(".sensor { color:white; font-weight: bold; background-color: #bcbcbc; padding: 1px; }");

12. Menampilkan pembacaan sensor.

// Web Page Heading
            client.println("</style></head><body><h1>ESP32 with BMP180</h1>");
            client.println("<table><tr><th>MEASUREMENT</th><th>VALUE</th></tr>");
            client.println("<tr><td>Temp. Celcius</td><td><span class=\"sensor\">");
            client.println(bmp.readTemperature());
            client.println(" *C</span></td></tr>");  
            client.println("<tr><td>Temp. Fahrenheit</td><td><span class=\"sensor\">");
            client.println(1.8 * bmp.readTemperature() + 32);
            client.println(" *F</span></td></tr>");       
            client.println("<tr><td>Pressure</td><td><span class=\"sensor\">");
            client.println(bmp.readPressure() / 100.0F);
            client.println(" Pa</span></td></tr>");
            client.println("<tr><td>Altitude</td><td><span class=\"sensor\">");
            client.println(bmp.readAltitude());
            client.println(" m</span></td></tr>"); 
            client.println("<tr><td>Pressure at sealevel (calculated)</td><td><span class=\"sensor\">");
            client.println(bmp.readSealevelPressure());
            client.println(" Pa</span></td></tr>");
            client.println("<tr><td>Real altitude</td><td><span class=\"sensor\">");
            client.println(bmp.readAltitude(102000));
            client.println(" m</span></td></tr>");
            client.println("</body></html>");

13. Menutup koneksi.

 // Clear the header variable
    header = "";
    // Close the connection
    client.stop();
    Serial.println("Client disconnected.");
    Serial.println("");

Ketiga, mengatur networks credential.

const char* ssid     = "iPhone";
const char* password = "abesarkkecilukecil";

Keempat, verify dan upload program pada Arduino Ide.

Kelima, buka Serial Monitor dan pastikan berada pada baud rate 115200. Kemudian, tekan tombol EN pada ESP32.

Keenam, ESP32 akan terhubung ke Wi-Fi dan mengeluarkan alamat IP ESP32 pada Serial Monitor. Salin alamat IP tersebut untuk mengakses server web ESP32.

Ke-tujuh, IP Address yang didapatkan adalah 172.20.10.2. Maka, ketik IP Address pada web.

Ke-delapan, pastikan juga berjalan di Serial Monitor.

Berikut hasil video percobaan yang dilakukan :

Cari Blog Ini

Sistem Embedded

ESP32 WITH WEB SERVER

Komentar

Posting Komentar

Postingan populer dari blog ini

LED Blinking ESP32

ESP32 WITH DATA VISUALIZATION

ESP32 WITH WI-FI COMMUNICATION