#define BUZZER_PIN 15   // Buzzer connected to GP15

void setup() {
  pinMode(BUZZER_PIN, OUTPUT);
}

void loop() {
  // Turn buzzer ON (1 kHz)
  analogWriteFreq(1000);     // Set PWM frequency to 1 kHz
  analogWrite(BUZZER_PIN, 128); // 50% duty cycle (0–255)
  delay(1000);

  // Turn buzzer OFF
  analogWrite(BUZZER_PIN, 0);
  delay(1000);
}