Wokwi - Online ESP32, STM32, Arduino Simulator

#include "DHTesp.h"
#include <LiquidCrystal_I2C.h>
#include <WiFi.h>
#include <WiFiClient.h>
#include <WebServer.h>
#include <uri/UriBraces.h>

#define WIFI_SSID "Wokwi-GUEST"
#define WIFI_PASSWORD ""
// Defining the WiFi channel speeds up the connection:
#define WIFI_CHANNEL 6

WebServer server(80);

const int LED1 = 33;
const int LED2 = 34;

bool led1State = false;
bool led2State = false;

#define I2C_ADDR 0x27
#define LCD_COLUMNS 16
#define LCD_LINES 2
#define LDR_PIN 14

const int DHT_PIN = 15;
const float BETA = 3950; // should match the Beta Coefficient of the thermistor
DHTesp dht;

LiquidCrystal_I2C lcd(I2C_ADDR, LCD_COLUMNS, LCD_LINES);

void sendHtml() {
  String response = R"(
    <!DOCTYPE html><html>
      <head>
        <title>ESP32 Web Server Demo</title>
        <meta name="viewport" content="width=device-width, initial-scale=1">
        <style>
          html { font-family: sans-serif; text-align: center; }
          body { display: inline-flex; flex-direction: column; }
          h1 { margin-bottom: 1.2em; } 
          h2 { margin: 0; }
          div { display: grid; grid-template-columns: 1fr 1fr; grid-template-rows: auto auto; grid-auto-flow: column; grid-gap: 1em; }
          .btn { background-color: #5B5; border: none; color: #fff; padding: 0.5em 1em;
                 font-size: 2em; text-decoration: none }
          .btn.OFF { background-color: #333; }
        </style>
      </head>
            
      <body>
        <h1>ESP32 Web Server</h1>

        <div>
          <h2>LED 1</h2>
          <a href="/toggle/1" class="btn LED1_TEXT">LED1_TEXT</a>
          <h2>LED 2</h2>
          <a href="/toggle/2" class="btn LED2_TEXT">LED2_TEXT</a>
        </div>
      </body>
    </html>
  )";
  response.replace("LED1_TEXT", led1State ? "ON" : "OFF");
  response.replace("LED2_TEXT", led2State ? "ON" : "OFF");
  server.send(200, "text/html", response);
}

void setup() {
  Serial.begin(115200);
  dht.setup(DHT_PIN, DHTesp::DHT22);
  lcd.init();
  lcd.backlight();
  pinMode(LDR_PIN, INPUT);
  Serial.begin(115200);
  pinMode(LED1, OUTPUT);
  pinMode(LED2, OUTPUT);
  WiFi.begin(WIFI_SSID, WIFI_PASSWORD, WIFI_CHANNEL);
  Serial.print("Connecting to WiFi ");
  Serial.print(WIFI_SSID);
  // Wait for connection
  while (WiFi.status() != WL_CONNECTED) {
    delay(100);
    Serial.print(".");
  }
  Serial.println(" Connected!");
  Serial.print("IP address: ");
  Serial.println(WiFi.localIP());
  server.on("/", sendHtml);
  server.on(UriBraces("/toggle/{}"), []() {
    String led = server.pathArg(0);
    Serial.print("Toggle LED #");
    Serial.println(led);

    switch (led.toInt()) {
      case 1:
        led1State = !led1State;
        digitalWrite(LED1, led1State);
        break;
      case 2:
        led2State = !led2State;
        digitalWrite(LED2, led2State);
        break;
    }
    sendHtml();
  });
}

void loop() {
  server.handleClient();
  delay(2);
  readdata1();
  TempAndHumidity  data = dht.getTempAndHumidity();
  lcd.print("Wokwi Online IOT");
  lcd.setCursor(0,0);
  lcd.print("Temp:" + String(data.temperature, 2) + "C");
  lcd.setCursor(0,1);
  lcd.print("Humidity: "+ String(data.humidity, 1)+ "%");
  Serial.println("Temp: " + String(data.temperature, 2) + "°C");
  Serial.println("Humidity: " + String(data.humidity, 1) + "%");
  Serial.println("---");
  delay(10000); // Wait for a new reading from the sensor (DHT22 has ~0.5Hz sample rate)
  lcd.clear();
}

void readdata1()
{
  lcd.setCursor(2, 0);
  lcd.print("Room: ");
  if (digitalRead(LDR_PIN) == LOW) {
    lcd.print("Light!");
  } else {
    lcd.print("Dark  ");
  }
  delay(100);
}