/*
Voltaat learn (http://learn.voltaat.com)
Link for full tutorial:
DHT11 library:
Adafruit sensor Library:
Wire Library:
LiquidCrystal I2C Library:
Tutorial: Simple Weather Station with LCD Display
Connections from the Arduino to the breadboard:
• Arduino 5v pin → breadboard 5v line
• Arduino GND pin → breadboard GND line
Connection form the DHT11:
• GND pin → Arduino GND pin
• Signal pin → Arduino digital pin 2
• VCC pin → Arduino 5V pin
Connection from the raindrops sensor:
• VCC pin → breadboard 5v line
• GND pin → breadboard GND line
• Signal pin → Arduino analog pin A0
Connection from the LCD:
• VCC pin → breadboard 5v line
• GND pin→ breadboard GND line
• SDA pin→ Arduino analog pin A4
• SCL pin → Arduino analog pin A5
*/
// Define libraries
#include "Wire.h" // include the Wire library for I2C communication
#include "LiquidCrystal_I2C.h" // include the LiquidCrystal_I2C library for the LCD display
#include "DHT.h" // include the DHT library for the DHT11 sensor
const int rainSensorPin = A0; // The analog pin that the rain sensor is connected to
DHT dht (2, DHT11); // Initialize the DHT11 sensor on digital pin 2
const float heavyRainfallThreshold = 2.0; // Threshold for heavy rainfall
LiquidCrystal_I2C lcd(0x27, 16, 2); // Initialize the LCD display
float prevT = -999.0; // Initialize previous temperature to an invalid value
float prevH = -999.0; // Initialize previous humidity to an invalid value
bool prevRain = false; // Initialize previous rain value to false
//Commands inside void setup run once
void setup() {
Serial.begin(9600); // Initialize serial communication at 9600 bits per second
lcd.init(); // Initialize the LCD display
lcd.backlight(); // Turn on the backlight
dht.begin(); // Start the DHT11 sensor
pinMode(rainSensorPin, INPUT); // Set the rain sensor pin as an input
lcd.clear(); // Clear the LCD display
lcd.setCursor(1, 0); // Set the cursor to the first row, second column
lcd.print("Voltaat Learn"); // Display a welcome message
delay(3000); // Wait for 3 seconds
lcd.clear(); // Clear the LCD display
lcd.setCursor(3, 0); // Set the cursor to the first row, fourth column
lcd.print("Welcome to"); // Display a welcome message
lcd.setCursor(1, 1); // Set the cursor to the second row, second column
lcd.print("Weather Station"); // Display a welcome message
delay(3000); // Wait for 3 seconds
}
//Commands inside void loop run forever
void loop() {
float T = dht.readTemperature(); // Read the temperature from the DHT11 sensor
float H = dht.readHumidity(); // Read the humidity from the DHT11 sensor
int rainSensorValue = analogRead(rainSensorPin); // Read the value from the rain sensor
bool isRaining = rainSensorValue < 500; // Determine if it is currently raining
// Only update the display if the values have changed
if (T != prevT || H != prevH || isRaining != prevRain) {
lcd.setCursor(2, 0); // Set the cursor to the first row, third column
lcd.print("Temp: "); // Display the temperature label
lcd.print(T); // Display the temperature
lcd.print((char)223); // Display the degree symbol
lcd.print("C"); // Display the Celsius unit
lcd.setCursor(0, 1); // Set the cursor to the second row, first column
if (isRaining) { // If it is currently raining
lcd.print("Raining "); // Display the rain status
} else { // If it is not currently raining
lcd.print("No Rain "); // Display the rain status
}
lcd.print("H:"); // Display the humidity label
lcd.print(H); // Display the humidity
lcd.print("%"); // Display the percentage symbol
// Store the current values as previous values for the next update
prevT = T;
prevH = H;
prevRain = isRaining;
}
delay(2000); // Wait for 2 seconds
}
