Tinkerbot 3.6.2: Controlling a buzzer with proximity sensor

Tinkerbot 3.6.2

#include <NewPing.h>
#include <NewTone.h>

const int ULTRASONIC_TRIGGER = 6;
const int ULTRASONIC_ECHO = 7;
const int BUZZER_PIN = 9;

#define MAX_DISTANCE 100

NewPing sonar(ULTRASONIC_TRIGGER, ULTRASONIC_ECHO, MAX_DISTANCE);


void setup() {
  pinMode(ULTRASONIC_TRIGGER, OUTPUT);
  pinMode(ULTRASONIC_ECHO, INPUT);
  
  pinMode(BUZZER_PIN, OUTPUT);
}


void loop() {
  int distance = sonar.ping_cm();
  // If distance value is 0, it means that the object is very far away
  if (distance == 0) {
    distance = MAX_DISTANCE;
  }
  // We are only interested in the 10cm to 20cm range, so we constrain
  // it to that range, and then map it to the brightness value (inverse map)
  distance = constrain(distance, 10, 20);
  // map the sensor values to a wide range of pitches
  int pitch = map(distance, 10, 20, 50, 5000);

  NewTone(9, pitch, 20);

  // wait for a moment
  delay(10);
}