Untitled

#include <Wire.h>
#include <LiquidCrystal_I2C.h>

// Define LCD
LiquidCrystal_I2C lcd(0x27, 16, 2);  // Adjust the I2C address if needed

// Define pins for sensor, LEDs, and buzzer
int sensorPin = A0;  // Analog pin for the pH sensor (simulating temperature here)
int greenLedPin = 2;  // Green LED (Neutral)
int yellowLedPin = 3; // Yellow LED (Low pH)
int redLedPin = 4;    // Red LED (High pH)
int buzzerPin = 5;    // Buzzer pin

void setup() {
  // Initialize LCD
  lcd.begin(16, 2);
  lcd.print("Initializing...");
  delay(2000);  // Display initial message for 2 seconds

  // Set LED and buzzer pins as outputs
  pinMode(greenLedPin, OUTPUT);
  pinMode(yellowLedPin, OUTPUT);
  pinMode(redLedPin, OUTPUT);
  pinMode(buzzerPin, OUTPUT);

  Serial.begin(9600);  // Start serial communication for debugging
}

void loop() {
  // Read the sensor value (simulating pH with temperature)
  int sensorValue = analogRead(sensorPin);

  // Convert the sensor value to voltage (for example, TMP36, adjust as needed)
  float voltage = sensorValue * (5.0 / 1023.0);  // Assuming 5V and 10-bit ADC
  float pHValue = (voltage - 0.5) * 100;  // Example for TMP36, adjust for your sensor
  
  // Display the pH value on the LCD (first line)
  lcd.clear();
  lcd.setCursor(0, 0);  // Move to the first line
  lcd.print("pH: ");
  lcd.print(pHValue);

  // Logic for LEDs and buzzer based on pH value
  if (pHValue >= 7.00 && pHValue <= 7.80) {  // Neutral range
    digitalWrite(greenLedPin, HIGH);   // Green LED (Neutral)
    digitalWrite(yellowLedPin, LOW);   // Turn off Yellow LED
    digitalWrite(redLedPin, LOW);      // Turn off Red LED
    digitalWrite(buzzerPin, LOW);      // No buzzer
    
    lcd.setCursor(0, 1);  // Move to the second line
    lcd.print("Status: Good");
  }
  else if (pHValue < 7.00) {  // Below the neutral range
    digitalWrite(greenLedPin, LOW);   // Turn off Green LED
    digitalWrite(yellowLedPin, HIGH); // Yellow LED (Low pH)
    digitalWrite(redLedPin, LOW);     // Turn off Red LED
    digitalWrite(buzzerPin, LOW);     // No buzzer
    
    lcd.setCursor(0, 1);  // Move to the second line
    lcd.print("Status: Bad");
  }
  else if (pHValue > 7.80) {  // Above the neutral range
    digitalWrite(greenLedPin, LOW);   // Turn off Green LED
    digitalWrite(yellowLedPin, LOW);  // Turn off Yellow LED
    digitalWrite(redLedPin, HIGH);    // Red LED (High pH)
    digitalWrite(buzzerPin, LOW);     // No buzzer
    
    lcd.setCursor(0, 1);  // Move to the second line
    lcd.print("Status: Bad");
  }

  // Extreme pH values (0-2 or 12-14)
  if ((pHValue >= 0 && pHValue <= 2) || (pHValue >= 12 && pHValue <= 14)) {
    digitalWrite(buzzerPin, HIGH);  // Turn on buzzer for extreme values
    lcd.setCursor(0, 1);  // Move to the second line
    lcd.print("Status: Bad");
  }

  delay(1000);  // Wait for 1 second before checking again
}