/*
  Melody

 Plays a melody

 circuit:
 * 8-ohm speaker on digital pin 8

 created 21 Jan 2010
 modified 30 Aug 2011
 by Tom Igoe

This example code is in the public domain.

 http://arduino.cc/en/Tutorial/Tone

 */
#include "pitches.h"
#include <Wire.h>

int distance = 0;                // Stores the calculated distance 
byte high, low = 0;              // High and low byte of distance
int shift = 0;                   // Value in shift bit register

#define ADDRESS       0x80 >> 1  // Arduino uses 7 bit addressing so we shift address right one bit
#define DISTANCE_REG  0x5E
#define SHIFT         0x35

#define buzzer 11
#define power_led 10

// Variables will change :
int ledState = LOW;             // ledState used to set the LED

// Generally, you should use "unsigned long" for variables that hold time
// The value will quickly become too large for an int to store
unsigned long previousMillis = 0;        // will store last time LED was updated

// constants won't change :
const long interval = 250;           // interval at which to blink (milliseconds)

// notes in the melody:
int melody[] = {
  NOTE_C4, NOTE_G3, NOTE_G3, NOTE_A3, NOTE_G3, 0, NOTE_B3, NOTE_C4
};

// note durations: 4 = quarter note, 8 = eighth note, etc.:
int noteDurations[] = {
  4, 8, 8, 4, 4, 4, 4, 4
};

void setup() {
  pinMode(power_led, OUTPUT);
  digitalWrite(power_led, ledState);
  // iterate over the notes of the melody:
  for (int thisNote = 0; thisNote < 8; thisNote++) {

    // to calculate the note duration, take one second
    // divided by the note type.
    //e.g. quarter note = 1000 / 4, eighth note = 1000/8, etc.
    int noteDuration = 1000 / noteDurations[thisNote];
    tone(buzzer, melody[thisNote], noteDuration);

    // to distinguish the notes, set a minimum time between them.
    // the note's duration + 30% seems to work well:
    int pauseBetweenNotes = noteDuration * 1.30;
    delay(pauseBetweenNotes);
    // stop the tone playing:
    noTone(buzzer);
  }
  // Start comms
  Wire.begin();
  Serial.begin(115200);
  
  delay(50);  // Delay so everything can power up
  analogReference(INTERNAL); 
  // Read the sift bit register from the module, used in calculating range
  Wire.beginTransmission(ADDRESS);    
  Wire.write(SHIFT);
  Wire.endTransmission();
  
  Wire.requestFrom(ADDRESS, 1);
  while(Wire.available() == 0);
  shift = Wire.read();
}

void loop() {
  unsigned long currentMillis = millis();
  if(currentMillis - previousMillis >= interval) {
    // save the last time you blinked the LED 
    previousMillis = currentMillis;   

    // if the LED is off turn it on and vice-versa:
    if (ledState == LOW)
      ledState = HIGH;
    else
      ledState = LOW;

    // set the LED with the ledState of the variable:
    digitalWrite(power_led, ledState);
  }
    // Request and read the 2 address bytes from the GP2Y0E02B
  Wire.beginTransmission(ADDRESS);
  Wire.write(DISTANCE_REG);
  Wire.endTransmission();
  
  Wire.requestFrom(ADDRESS, 2);
  
  while(Wire.available() < 2);
  
  high = Wire.read();
  low = Wire.read();
  
  distance = (high * 16 + low)/16/(int)pow(2,shift); // Calculate the range in CM
  
  Serial.print("Distance is ");
  Serial.print(distance);
  Serial.println("CM");

  Serial.print("Battery is ");
  Serial.print(analogRead(A5)*(2*2560/1023.));
  Serial.println("mV");
  
  
  delay(50);
}