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#include <Wire.h> //BH1750 IIC Mode 
#include <math.h> 
int BH1750address = 0x23; //setting i2c address
byte buff[2];
void setup()
{
  Wire.begin();
  Serial.begin(115200);//init Serail band rate
  pinMode(2, OUTPUT);     
  
  
}
 
void loop()
{
  int i;
  uint16_t val=0;
  BH1750_Init(BH1750address);
  delay(200);
 
  if(2==BH1750_Read(BH1750address))
  {
    val=((buff[0]<<8)|buff[1])/1.2;
    Serial.print(val,DEC);

//IF
if (val < 200 && val >180)

{
  delay(1000);

  digitalWrite(2,HIGH);
  delay(100);
      Serial.print("ON!");

  
}  //END 
else {
  
    digitalWrite(2,LOW);
    Serial.print("NF!");


}//END ELSE
Serial.println("[lx]"); 
  }
  delay(150);
}
int BH1750_Read(int address) //
{
  int i=0;
  Wire.beginTransmission(address);
  Wire.requestFrom(address, 2);
  while(Wire.available()) //
  {
    buff[i] = Wire.read();  // receive one byte
    i++;
  }
  Wire.endTransmission();  
  return i;
} 
void BH1750_Init(int address) 
{
  Wire.beginTransmission(address);
  Wire.write(0x10);//1lx reolution 120ms
  Wire.endTransmission();
}

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