ESP32 Web Server with BMP180

4 min readApr 3, 2021

Hai hai haiiii ol! Balik lagi sama gue Paul. Di tulisan kali ini aku akan menjelaskan cara membangun server dengan ESP32. Sebenernya minggu lalu kita sudah melakukan ini. Maksudnya? Jadi kita kemarin sudah berhasil menyalakan lampu dengan cara membangun server bukan? Nah, pada kali ini, kita juga akan melakukan hal yang hampir serupa, namun tak sama. Kita akan melihat pembacaan sensor melalui server yang dibangun ESP32. Penasaran kan? Yuk, langsung aja ikutin!

Pertama-tama, kita siapin dulu yok alat dan bahannya. Berikut adalah rinciannya.

Microcontroller ESP32
Breadboard
Sensor BMP180
Beberapa buah kabel jumper
Kabel USB dan Laptop

Berikut adalah skema diagram dari rangkaian yang akan kita buat.

Dan ini adalah rangkaian yang aku buat.

Setelah rangkaiannya sudah kamu buat, sekarang coba copy paste kode ini.

/*********
 Rui Santos
 Complete project details at https://randomnerdtutorials.com 
*********/
// Load Wi-Fi library
#include <WiFi.h>
#include <Wire.h>
#include <Adafruit_BMP085.h>
Adafruit_BMP085 bmp;
// Replace with your network credentials
const char* ssid = “MentawaiRaya”;
const char* password = “12345678”;
// 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(0x76)) {
 Serial.println(“Could not find a valid BME280 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>#weather {font-family: Trebuchet MS, sans-serif;border-collapse: collapse;width: 100%;}”);
 client.println(“#weather td, #customers th {border: 1px solid #ddd;padding: 8px;}”);
 client.println(“#weather tr:nth-child(even){background-color: #f2f2f2;}”);
 client.println(“#weather tr:hover {background-color: #ddd;}”);
 client.println(“#weather th {padding-top: 12px;padding-bottom: 12px;text-align: center;background-color: #FF9ABB;color: black;}”);
 client.println(“body { text-align: center; font-family: \”Trebuchet MS\”, Arial;}”);
 client.println(“.sensor { color:black; font-weight: bold; background-color: white; padding: 1px; }”);
 
 // Web Page Heading
 client.println(“</style></head><body><h1>ESP32 with BMP180</h1>”);
 client.println(“<table id=’weather’><tr><th>MEASUREMENT</th><th>VALUE</th></tr>”);
 client.println(“<tr><td>Temp. Celsius</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(“ hPa</span></td></tr>”);
 client.println(“<tr><td>Approx. Altitude</td><td><span class=\”sensor\”>”);
 client.println(bmp.readAltitude());
 client.println(“ m</span></td></tr>”); 
 client.println(“<tr><td>Sea Level Pressure</td><td><span class=\”sensor\”>”);
 client.println(bmp.readSealevelPressure());
 client.println(“ %</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(“”);
 }
}

Di baris kode diatas, ada bagian untuk nama SSID serta password. Disitu, untuk SSID bisa kalian ganti dengan nama wi-fi yang sekarang kalian gunakan, dan jangan lupa ketikkan juga passwordnya.

Sekarang, verify dan upload kode yang barusan.

Setelah itu klik icon search yang berada di sebelah ujung kanan atas.

Lalu tekan tombol EN di ESP32. Nanti baca alamat IP Address nya.