Description

We built a piano-like instrument that helps you learn how to play a song. When the program is run, the notes of a song are displayed through 4 LEDs, the user then presses the keys that correspond to the LEDs and the correct note is emitted from the speaker.

Components

Arduino

Breadboard

4 LEDs (red, green, blue, yellow)

4 FSRs

4 220 resistors

4 10K resistors 

1 Potentiometer

1 Piezo speaker

Material to construct the piano

wiring

Arduino Code

/*

Some of the code was adapted from Wesley Willett of this class! 

*/

//The four input pins

int inputPin1 = 0; 

int inputPin2 = 1;

int inputPin3 = 2;

int inputPin4 = 3;

//Speaker Pin

int speakerPin = 6;

//The four colours

int ledPin1 = 8;

int ledPin2 = 9;

int ledPin3 = 10;

int ledPin4 = 11;

//The potentiometer pin

int potPin = 5;

//Variables to store the pressures on the FSR without any explicit pressures being applied to it

int valDefault1 = 0;     

int valDefault2 = 0;

int valDefault3 = 0;

int valDefault4 = 0;

//Variables to read/store the user input through the FSR

int valRead1 = 0;

int valRead2 = 0;

int valRead3 = 0;

int valRead4 = 0;

int i = 0;

int index = 0;

//THE TUNE COUNT

int MAX_COUNT = 24;

int SENSITIVITY = 20;

int count = 0;

//Narrow down to the required four

byte names[] = {'c', 'd', 'e', 'f' /*, 'g', 'a', 'b', 'C'*/};

int tones[] = {1915, 1700, 1519, 1432, 1275, 1136, 1014, 956};

//The musical note (From a file?)

byte melody[] = "2d2c1f2c2d2e2d2c2f2d2c2c2d2e1f2c2f";

//byte hello[] = "1c1p1d1p1e1p1f1p1g1p1a1p1b1p1C1p";

byte hello[] = "2c1p";

byte goodbye[] = "2d1p";

//byte goodbye[] = "1C1p1b1p1a1p1g1p1f1p1e1p1d1p1c1p";

byte wave[] = "2e1p";

byte wave2[] = "2f1p";

int count2 = 0;

int count3 = 0;

int statePin = LOW;

boolean isOpen = true;

int waveWait = 0;

void setup() {

  pinMode(ledPin1, OUTPUT);  // declare the ledPin as an OUTPUT

  pinMode(ledPin2, OUTPUT);  // declare the ledPin as an OUTPUT

  pinMode(ledPin3, OUTPUT);  // declare the ledPin as an OUTPUT

  pinMode(ledPin4, OUTPUT);  // declare the ledPin as an OUTPUT

  pinMode(speakerPin, OUTPUT);  // declare the ledPin as an OUTPUT

  valDefault1 = analogRead(inputPin1);

  valDefault2 = analogRead(inputPin2);

  valDefault3 = analogRead(inputPin3);

  valDefault4 = analogRead(inputPin4);

  Serial.println("Ready");

}

void loop() {

  //Narrow down to the required four

  //byte names[] = {'c', 'd', 'e', 'f' /*, 'g', 'a', 'b', 'C'*/};

  //int tones[] = {1915, 1700, 1519, 1432, 1275, 1136, 1014, 956};

  //The musical note (From a file?)

  //byte melody[] = "2d2c1f2c2d2e2d2c2f2d2c2c2d2e1f2c2f";

  //Sound output note

  /*

   * note 	frequency 	period 	PW (timeHigh)	

   * c 	        261 Hz 	        3830 	1915 	

   * d 	        294 Hz 	        3400 	1700 	

   * e 	        329 Hz 	        3038 	1519 	

   * f 	        349 Hz 	        2864 	1432 	

   * g 	        392 Hz 	        2550 	1275 	

   * a 	        440 Hz 	        2272 	1136 	

   * b 	        493 Hz 	        2028	1014	

   * C	        523 Hz	        1912 	956

  */

  //read note

  int potVal = analogRead(potPin);

  float potInducedDelay = potVal/512;

  int noteDelay = melody[index*2] - 48;

  int totalDelay = (int)(200 * potInducedDelay * noteDelay);

  for(i=0; i < 4/*Change*/; i++) {

    if(melody[index*2 + 1] == 'c') {

      analogWrite(ledPin1, 255);

      //Continuation of the note

      delay(totalDelay);

      analogWrite(ledPin1, 0);        

    }

    if(melody[index*2 + 1] == 'd') {

      analogWrite(ledPin2, 255);

      //Continuation of the note

      delay(totalDelay);

      analogWrite(ledPin2, 0);        

    }

    if(melody[index*2 + 1] == 'e') {

      analogWrite(ledPin3, 255);

      //Continuation of the note

      delay(totalDelay);

      analogWrite(ledPin3, 0);        

    }

	if(melody[index*2 + 1] == 'f') {

      analogWrite(ledPin4, 255);

      //Continuation of the note

      delay(totalDelay);

      analogWrite(ledPin4, 0);        

    }

  }

  //Read values from sensors

  valRead1 = analogRead(inputPin1);

  valRead2 = analogRead(inputPin2);

  valRead3 = analogRead(inputPin3);

  valRead4 = analogRead(inputPin4);

  if(valRead1 - valDefault1 > SENSITIVITY) {

	playHello();

  }

  if(valRead2 - valDefault2 > SENSITIVITY) {

	playGoodbye();

  }

  if(valRead3 - valDefault3 > SENSITIVITY) {

	playWave();

  }

  if(valRead4 - valDefault4 > SENSITIVITY) {

	playWave2();

  }

Serial.println(valRead1);

Serial.println(valRead2);

Serial.println(valRead3);

Serial.println(valRead4);

  index++;

  if(index == MAX_COUNT) {

    index = 0;

  }

}

void playHello(){

	playJams(hello,2);

}

void playGoodbye(){

	playJams(goodbye,2);

}

void playWave(){

	playJams(wave,2);

}

void playWave2(){

	playJams(wave2,2);

}

//plays the a series of notes defined in an array

void playJams(byte jams[], int length){

	for (count = 0; count < length; count++) {

		statePin = !statePin;

		for (count3 = 0; count3 <= (jams[count*2] - 48) * 30; count3++) {

			for (count2=0;count2<8;count2++) {

				if (names[count2] == jams[count*2 + 1]) {

					digitalWrite(speakerPin,HIGH);

					delayMicroseconds(tones[count2]);

					digitalWrite(speakerPin, LOW);

					delayMicroseconds(tones[count2]);

				}

				if (jams[count*2 + 1] == 'p') {

					// make a pause of a certain size

					digitalWrite(speakerPin, 0);

					delayMicroseconds(500);

				}

			}

		}

	}

}

Images

http://photo.xuite.net/berkeleychiu/2113602/1.jpg

http://photo.xuite.net/berkeleychiu/2113602/2.jpg

http://photo.xuite.net/berkeleychiu/2113602/3.jpg

http://photo.xuite.net/berkeleychiu/2113602/4.jpg

Video 

http://www.youtube.com/watch?v=p6NiDoXdgCI