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

#define SENSOR_PIN 34

LiquidCrystal_I2C lcd(0x27, 16, 2);

float filteredValue = 0;
float alpha = 0.1;   //  Filter strength

void setup() {

  Serial.begin(115200);

  lcd.init();
  lcd.backlight();

  lcd.setCursor(0,0);
  lcd.print("ESP32 ADC SYS");
  delay(2000);
  lcd.clear();
}

void loop() {

  int rawValue = analogRead(SENSOR_PIN);

  // Low Pass Filter
  filteredValue =
      alpha * rawValue +
      (1 - alpha) * filteredValue;

  // LCD Display
  lcd.setCursor(0,0);
  lcd.print("Raw:");
  lcd.print(rawValue);
  lcd.print("    ");

  lcd.setCursor(0,1);
  lcd.print("Filt:");
  lcd.print((int)filteredValue);
  lcd.print("    ");

  // Serial Monitor
  Serial.print("Raw Value: ");
  Serial.print(rawValue);

  Serial.print("  Filtered: ");
  Serial.println(filteredValue);

  delay(200);
}