#include <WiFi.h>
#include <WiFiClient.h>
#include <PubSubClient.h>
#include <DHT.h>
long previousMillisAnalog = 0;
int intervalAnalog = 1500;
long previousMillishumidity = 0;
int intervalhumidity = 1500;
float HData;
// Wi-Fi credentials
const char* ssid = "Wokwi-GUEST";
const char* password = "";
const char* hostname = "broker.hivemq.com";
// MQTT client name and port
WiFiClient espClient;
PubSubClient client(espClient);
const char* espClientName = "esp32Client_s10245569"; // yourStudentID must be unique
int PORTNUM = 1883;
// Define sensor pins
#define LDR_PIN 35 // GPIO35 for analog input
#define DHT_PIN 32 // GPI32 for DHT22
#define POT_PIN 33 // GPIO33 for analog input
/*
// Define additional GPIO pins
#define LED1_PIN 18 // GPIO18 for LED1
#define LED2_PIN 19 // GPIO19 for LED2
#define LED3_PIN 23 // GPIO23 for LED3
*/
// Create DHT sensor instance
DHT dht(DHT_PIN, DHT22);
// Timing variables
long previousMillis = 0;
const long interval = 2000; // Interval to publish sensor data (2 seconds)
void setup_wifi()
{
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED)
{
delay(1000);
Serial.print(".");
}
Serial.println();
Serial.print("Connected to ");
Serial.println(ssid);
Serial.print("Given IP by the router to ESP32 is ");
Serial.println(WiFi.localIP());
}
void connectMQTT()
{
while (!client.connected())
{
Serial.println("Connecting to MQTT ...");
if (client.connect(espClientName))
{
Serial.println("Connected");
MQTTSubscribe();
} else
{
Serial.print("Failed with state ");
Serial.print(client.state());
delay(2000);
}
}
}
void callback(String topic, byte* payload, unsigned int length)
{
// Process incoming messages
String messageTemp;
Serial.print("Message received in topic: ");
Serial.print(topic);
Serial.print(" length is: ");
Serial.println(length);
Serial.print("Data received from broker: ");
for (int i = 0; i < length; i++)
{
Serial.print((char)payload[i]);
messageTemp += (char)payload[i];
}
/*
if (topic == "DEIOT/S10245569") {
if (messageTemp == "LED1_ON") {
digitalWrite(LED1_PIN, LOW); // Turn LED1 on
Serial.println("LED1 turned on");
} else if (messageTemp == "LED1_OFF") {
digitalWrite(LED1_PIN, HIGH); // Turn LED1 off
Serial.println("LED1 turned off");
} else if (messageTemp == "LED2_ON") {
digitalWrite(LED2_PIN, LOW); // Turn LED2 on
Serial.println("LED2 turned on");
} else if (messageTemp == "LED2_OFF") {
digitalWrite(LED2_PIN, HIGH); // Turn LED2 off
Serial.println("LED2 turned off");
} else if (messageTemp == "LED3_ON") {
digitalWrite(LED3_PIN, LOW); // Turn LED3 on
Serial.println("LED3 turned on");
} else if (messageTemp == "LED3_OFF") {
digitalWrite(LED3_PIN, HIGH); // Turn LED3 off
Serial.println("LED3 turned off");
}
}*/
}
void MQTTSubscribe()
{
client.subscribe("DEIOT/S10245569");
}
void setup_MQTT()
{
client.setServer(hostname, PORTNUM);
client.setCallback(callback);
}
void setup() {
Serial.begin(115200);
setup_wifi();
setup_MQTT();
dht.begin();
/*
// Initialize LED pins
pinMode(LED1_PIN, OUTPUT);
pinMode(LED2_PIN, OUTPUT);
pinMode(LED3_PIN, OUTPUT);
// Turn LEDs off initially
digitalWrite(LED1_PIN, HIGH);
digitalWrite(LED2_PIN, HIGH);
digitalWrite(LED3_PIN, HIGH);*/
}
void loop()
{
if (!client.connected())
{
connectMQTT();
}
client.loop();
long currentMillis = millis();
if (currentMillis - previousMillis >= interval)
{
previousMillis = currentMillis;
// Read sensor values
int ldrValue = analogRead(LDR_PIN);
float humidity = dht.readHumidity();
float temperature = dht.readTemperature();
int potValue = analogRead(POT_PIN);
// Check if any reads failed and exit early (to try again)
if (isnan(humidity) || isnan(temperature))
{
Serial.println("Failed to read from DHT sensor!");
return;
}
// Print sensor values to serial monitor
Serial.print("LDR: "); Serial.println(ldrValue);
Serial.print("Humidity: "); Serial.print(humidity); Serial.println(" %");
Serial.print("Temperature: "); Serial.print(temperature); Serial.println(" *C");
Serial.print("Potentiometer: "); Serial.println(potValue);
// Create a JSON payload
String payload = "{";
payload += "\"ldr\":" + String(ldrValue) + ",";
payload += "\"humidity\":" + String(humidity) + ",";
payload += "\"temperature\":" + String(temperature) + ",";
payload += "\"potentiometer\":" + String(potValue);
payload += "}";
}
/*
int adcRes;
long currentMillisAnalog = millis();
if ( currentMillisAnalog - previousMillisAnalog >= intervalAnalog)
{
previousMillisAnalog = currentMillisAnalog;
adcRes = analogRead(A5);
Serial.print("Analog Value = ");
Serial.println(adcRes);
String payload;
if (adcRes > 2500)
{
payload = "Alert";
}
else
{
payload = "OK";
}
// Publish payload to MQTT broker
client.publish("DEIOT/S10245569", payload.c_str());
}
*/
long currentMillishumidity = millis();
if ( currentMillishumidity - previousMillishumidity >= intervalhumidity)
{
previousMillishumidity = currentMillishumidity;
String payloadh;
if (HData > 30.0)
{
payloadh = "Alert";
}
else
{
payloadh = "OK";
}
// Publish payload to MQTT broker
client.publish("ADC/LT50/9601156U", payloadh.c_str());
}
}