Play a tune on device movement!

movement-music.ino

/**
 * Use a LSM303 to detect movement. When the chip moves than a song is played!
 * 
 * To compile requires `piches.h` that is found here: https://www.arduino.cc/en/Tutorial/toneMelody
 * And the LSM303 Library is required: https://github.com/pololu/lsm303-arduino
 */

#include <Wire.h>
#include <LSM303.h>
#include "pitches.h"

#define BUZZPIN 9
#define SENSITIVITY 350

LSM303 compass;


int melody[] = {
  NOTE_C4, NOTE_G3, NOTE_G3, NOTE_A3, NOTE_G3, 0, NOTE_B3, NOTE_C4
};

int noteDurations[] = {
  4, 8, 8, 4, 4, 4, 4, 4
};

const int buzzerPin = 9;
unsigned long buzzUntil = 0;

float lastX, lastY, lastZ, nowX, nowY, nowZ;

void setup() {
  Serial.begin(9600);
  Serial.println("Begin init");

  pinMode(BUZZPIN, OUTPUT);
  Wire.begin();
  compass.init();
  compass.enableDefault();
  
  Serial.println("finished init");
}

void loop() {
  readAc();
  if(abs(nowX - lastX) > SENSITIVITY || abs(nowY - lastY) > SENSITIVITY || abs(nowZ - lastZ) > SENSITIVITY) { 
    for (int thisNote = 0; thisNote < sizeof(melody)/sizeof(int); thisNote++) {
      int noteDuration = 1000 / noteDurations[thisNote];
      tone(buzzerPin, melody[thisNote], noteDuration);
  
      int pauseBetweenNotes = noteDuration * 1.30;
      delay(pauseBetweenNotes);

      noTone(buzzerPin);
    }
    readAc();
  }
  lastX = nowX;
  lastY = nowY;
  lastZ = nowZ;
  delay(100);
}

void readAc(){
  compass.readAcc();

  nowX = compass.a.x >> 4;
  nowY = compass.a.y >> 4;
  nowZ = compass.a.z >> 4;
}