pitches.h

/*************************************************
 * Public Constants
 *************************************************/

#define NOTE_B0  31
#define NOTE_C1  33
#define NOTE_CS1 35
#define NOTE_D1  37
#define NOTE_DS1 39
#define NOTE_E1  41
#define NOTE_F1  44
#define NOTE_FS1 46
#define NOTE_G1  49
#define NOTE_GS1 52
#define NOTE_A1  55
#define NOTE_AS1 58
#define NOTE_B1  62
#define NOTE_C2  65
#define NOTE_CS2 69
#define NOTE_D2  73
#define NOTE_DS2 78
#define NOTE_E2  82
#define NOTE_F2  87
#define NOTE_FS2 93
#define NOTE_G2  98
#define NOTE_GS2 104
#define NOTE_A2  110
#define NOTE_AS2 117
#define NOTE_B2  123
#define NOTE_C3  131
#define NOTE_CS3 139
#define NOTE_D3  147
#define NOTE_DS3 156
#define NOTE_E3  165
#define NOTE_F3  175
#define NOTE_FS3 185
#define NOTE_G3  196
#define NOTE_GS3 208
#define NOTE_A3  220
#define NOTE_AS3 233
#define NOTE_B3  247
#define NOTE_C4  262
#define NOTE_CS4 277
#define NOTE_D4  294
#define NOTE_DS4 311
#define NOTE_E4  330
#define NOTE_F4  349
#define NOTE_FS4 370
#define NOTE_G4  392
#define NOTE_GS4 415
#define NOTE_A4  440
#define NOTE_AS4 466
#define NOTE_B4  494
#define NOTE_C5  523
#define NOTE_CS5 554
#define NOTE_D5  587
#define NOTE_DS5 622
#define NOTE_E5  659
#define NOTE_F5  698
#define NOTE_FS5 740
#define NOTE_G5  784
#define NOTE_GS5 831
#define NOTE_A5  880
#define NOTE_AS5 932
#define NOTE_B5  988
#define NOTE_C6  1047
#define NOTE_CS6 1109
#define NOTE_D6  1175
#define NOTE_DS6 1245
#define NOTE_E6  1319
#define NOTE_F6  1397
#define NOTE_FS6 1480
#define NOTE_G6  1568
#define NOTE_GS6 1661
#define NOTE_A6  1760
#define NOTE_AS6 1865
#define NOTE_B6  1976
#define NOTE_C7  2093
#define NOTE_CS7 2217
#define NOTE_D7  2349
#define NOTE_DS7 2489
#define NOTE_E7  2637
#define NOTE_F7  2794
#define NOTE_FS7 2960
#define NOTE_G7  3136
#define NOTE_GS7 3322
#define NOTE_A7  3520
#define NOTE_AS7 3729
#define NOTE_B7  3951
#define NOTE_C8  4186
#define NOTE_CS8 4435
#define NOTE_D8  4699
#define NOTE_DS8 4978

Prototype.ino

/*
 * V&A Wearables Prototype - Using a ... to change the ....
 * @author Your name goes here.
 * 13th November 2015
 * 
 */

#include "pitches.h"

int sensorPin = 1;   // The number of the input pin for the pressure sensor
int ledPin = 0;       // The number of the output pin for the LED
int speakerPin = 1;  // The number of the output pin for the speaker

int brightness = 0;

// notes in the melody:
int melody[] = {
  NOTE_C6, NOTE_G5, NOTE_G5, NOTE_A5, NOTE_G5, 0, NOTE_B5, NOTE_C6
};

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

boolean isPlaying = false;

void setup() {
  // Tell the Gemma that the speaker and LED pins are outputs
  pinMode(speakerPin, OUTPUT);
  pinMode(ledPin, OUTPUT);
  // Tell the Gemma that the sensor pin is an input
  pinMode(sensorPin, INPUT);
}

void loop() {
  
  // Read the value of the pressure sensor (variable resistor).
  // analogRead() returns a range of values.
  // The value increases the more pressure is
  // applied to our sensor.
  int sensorReading = analogRead(sensorPin);

  // The range of values we get from our sensorReading
  // will vary depending on the resistance of our pressure
  // sensor. We estimate that the range is approximately
  // between 0 and 50 depending on the pressure sensor.

  // The LED brightness is controlled by passing a value
  // between 0 and 255. We therefore need to convert/map our
  // sensorReading to this range.
  int brightness = map(sensorReading, 0, 100, 0, 255);

  if (sensorReading >= 50) {
    playMelody();
    delay(50);
  } else {
    analogWrite(ledPin, brightness); 
    delay(50);
  }
}

void playMelody() {
  // Do not play if already playing.
  if(isPlaying == true){
    return;
  }
  isPlaying = true;
  // iterate over the notes of the melody:
  for (int thisNote = 0; thisNote < 8; thisNote++) {

    int noteDuration = 1000 / noteDurations[thisNote];
    beep(speakerPin, 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);
  }
  isPlaying = false;
}

// The function that produces the sound.
void beep (unsigned char speakerPin, int frequencyInHertz, long timeInMilliseconds) {
  int x;
  long delayAmount = (long)(1000000 / frequencyInHertz);
  long loopTime = (long)((timeInMilliseconds * 1000) / (delayAmount * 2));
  for (x = 0; x < loopTime; x++) {
    digitalWrite(speakerPin, HIGH);
    delayMicroseconds(delayAmount);
    digitalWrite(speakerPin, LOW);
    delayMicroseconds(delayAmount);
  }
}