//This sketch will turn ‘ON’  the Piezo Buzzer once when the program start. 
#define BUZZER_PIN 18 // ESP32 GIOP18 pin connected to Buzzer's pin

void setup() {
  // put your setup code here, to run once:
  pinMode(BUZZER_PIN, OUTPUT);       // set ESP32 pin to output mode

}
void loop() {
  analogWrite(BUZZER_PIN,250); //Turn the Buzzer ON
  delay(500);
  analogWrite(BUZZER_PIN,LOW); //Turn the BUZZER OFF
}