---

#define BUZZER 9
#define LED 3
#define PR A0

int prValue;
int freq;

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

void loop()
{
  prValue = analogRead(PR);

  freq = map(prValue, 0, 1023, 200, 3000);

  tone(BUZZER, freq);

  if (freq >= 2000)
  {
    digitalWrite(LED, HIGH);
  }
  else
  {
    digitalWrite(LED, LOW);
  }

  delay(10);
}