A broken cathode tube display coming back to life in a new digital form — a material manifestation of Beethoven’s “Ode to Joy”.

Hummin.ino

// Hummin
// A broken cathode tube display coming back to life in a 
// new digital form — a material manifestation of Beethoven’s “Ode to Joy”.

// Assembly: https://bfadtdeviceart.wordpress.com/2016/09/06/hummin/

// Created by Michael Braverman
// September 3, 2016

int cathodePin = 7;
int blinkPin = 13;


int speakerPin = 8;
int length = 62; // the number of notes
char notes[] = "eefggfedccdeeddeefggfedccdedccddecdefecdefedcdgeefggfedccdedcc "; // a space represents a rest
int beats[] = { 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2};
int tempo = 100;

void playTone(int tone, int duration) {
  for (long i = 0; i < duration * 1000L; i +=tone * 2) {
    digitalWrite(speakerPin, HIGH);
    digitalWrite(blinkPin, HIGH);
    delayMicroseconds(tone);
    digitalWrite(speakerPin, LOW);
    digitalWrite(blinkPin, LOW);
    delayMicroseconds(tone);
  }
}

void playNote(char note, int duration) {
  char names[] = { 'c', 'd', 'e', 'f', 'g', 'a', 'b'};
  int tones[] = { 1915, 1700, 1519, 1432, 1275, 1136, 1014};
  // play the tone corresponding to the note name
  for (int i = 0; i < 8; i++) {
    if (names[i] == note) {
      playTone(tones[i], duration);
    }
  }
}

void setup() {
  Serial.begin(9600);
  pinMode(speakerPin, OUTPUT);
  pinMode(cathodePin, OUTPUT);
  pinMode(blinkPin, OUTPUT);
}

void loop() {
  for (int i = 0; i < length; i++) {
    if (notes[i] == ' ') {
      delay(beats[i] *tempo); //rest
    } else {
      playNote(notes[i], beats[i] *tempo);
      Serial.println(notes[i]);
    }

    // pause between notes
    delay((tempo /3)*2);
    digitalWrite(cathodePin, HIGH);
    delay(tempo /3);
    digitalWrite(cathodePin, LOW);
  }
}