#include <LiquidCrystal_I2C.h>
int ldrPin = A0;
int ledPin = 2;
const float GAMMA = 0.7;
const float RL10 = 50;
LiquidCrystal_I2C lcd(0x27,16,2);
void setup() {
pinMode(ledPin, OUTPUT);
lcd.init();
lcd.backlight();
}
void loop() {
int ldrValue = analogRead(ldrPin);
float voltase = ldrValue / 1024. * 5;
float resistansi = 2000 * voltase / (1-voltase / 5);
float kecerahan = pow(RL10 * 1e3 * pow(10, GAMMA) / resistansi,(1/GAMMA));
lcd.setCursor(0,0);
lcd.print("Cahaya: ");
if(kecerahan > 50){
lcd.print("Terang");
digitalWrite(ledPin, LOW);
}
else{
lcd.print("Gelap ");
digitalWrite(ledPin, HIGH);
}
lcd.setCursor(0, 1);
lcd.print("Lux: ");
lcd.print(kecerahan);
lcd.print(" ");
delay(100);
}