2. Sample Project – Smart Temperature Monitor

🎯 Objective: Monitor room temperature and send alerts if temperature > 30°C.

The primary goal of this project is to monitor the temperature in a room. The system is designed to alert users if the temperature exceeds 30 degrees Celsius. This threshold can be crucial in environments where maintaining a specific temperature is necessary, such as in labs or storage facilities for sensitive materials.

Think of it like a smart thermostat in your home that warns you when it gets too hot, helping you to maintain a comfortable environment. Just as you wouldn't want your room to get too warm, certain materials or processes can be negatively affected by excessive heat.

🧱 Components: ● ESP32 microcontroller ● DHT11 temperature & humidity sensor ● Firebase Realtime Database ● OLED Display (optional)

To build the Smart Temperature Monitor, you'll need specific components. The ESP32 microcontroller serves as the brain of the project, processing the data from the temperature sensor. The DHT11 sensor measures both temperature and humidity levels. The Firebase Realtime Database is used to store the temperature data and enable real-time access from anywhere. An OLED display can be used optionally to visualize the temperature readings directly on the device.

Imagine your project is a weather station. The ESP32 is like the station's crew, the DHT11 is the weather instrument measuring temperature and humidity, Firebase acts as the central hub where all the data is logged and available, and the OLED display is like the digital screen showing the latest weather updates at a glance.

🔌 Circuit Connections: ● DHT11 → Data pin to GPIO4 of ESP32 ● VCC and GND connected appropriately

This section describes how to wire the components together. The DHT11 sensor's data pin is connected to GPIO4 of the ESP32, which allows the microcontroller to receive temperature data from the sensor. Additionally, it's essential to connect the power supply pins (VCC and GND) of the DHT11 correctly to ensure it operates effectively. Proper circuit connections are crucial for the functionality of any electronic project.

Think of this as setting up a telephone line to ensure communication. The data wire from the DHT11 to the GPIO4 pin is like the phone line directly connecting two parties, while VCC (power) and GND (ground) are essential to keep the conversation going by providing the necessary energy.

💻 Sample Code (ESP32 + Firebase):

#include <FirebaseESP32.h>
#include <DHT.h>
#define DHTPIN 4
#define DHTTYPE DHT11
DHT dht(DHTPIN, DHTTYPE);
// Firebase setup
FirebaseData firebaseData;
String path = "/sensor/temp";
void setup() {
Serial.begin(115200);
dht.begin();
Firebase.begin("your_project.firebaseio.com",
"your_database_secret");
}
void loop() {
float t = dht.readTemperature();
Firebase.setFloat(firebaseData, path, t);
delay(2000);
}

The provided code snippet outlines how to program the ESP32 to communicate with the DHT11 sensor and send the temperature data to Firebase. It includes library imports for Firebase and the DHT sensor, defines the pin configuration, and establishes the Firebase connection in the setup function. In the loop function, it continuously reads the temperature from the sensor and uploads this data to Firebase every two seconds.

Consider this code as a recipe for baking a cake. Each ingredient (the different parts of the code) serves a purpose, working together to create the final product (the functioning temperature monitor). Just like following the recipe step-by-step ensures the cake rises perfectly, following the code sequence allows the ESP32 to correctly monitor the temperature and send it to the cloud.

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