int led[8]={19,18,5,17,16,4,0,2};
byte buzzer=2;
byte state=true;
byte state1=true;
void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  Serial.println("Hello, ESP32!");
 for(int i=0;i<8;i++)
 {
  pinMode(led[i], OUTPUT);
 }
}

void loop() 
{
}

void serialEvent()
{
  while (Serial.available()) 
  {
    char ch = Serial.read();
    
    Serial.print(ch);
    if(ch=='1')
    {
      led_on_off(state);
      state=!state;
    }
    
    if(ch=='2')
    {
      buzzer_on_off(state1);
      state1=!state1;
    }
    
  }
}

void led_on_off(byte state)
{
  if(state)
  {
    for(int i=0;i<8;i++)
    {
      digitalWrite(led[i], HIGH);
    }
  }
  else
  {
    for(int i=0;i<8;i++)
    {
      digitalWrite(led[i], LOW);
    }
    
  }
}


void buzzer_on_off(byte state1)
{
  if(state1)
  {
    digitalWrite(buzzer,HIGH);
    Serial.println("BUZZER ON");
    
  }
  else
  {
    digitalWrite(buzzer,LOW);
    Serial.println("BUZZER OFF");
    
  }
}