// passive buzzer musical scale
// keyboard scale:  https://i.pinimg.com/originals/cf/72/9a/cf729ae2213a849fe6b8cc527a0e7471.png

#include "freqs.h"  // adapted from pitches.h:  https://gist.github.com/mikeputnam/2820675
int duration, dur = 500, spkr_pin = 3;
const int notes = 10;
const int scales = 12;

const int scale[scales][notes] = {
  // N = natural S = sharp
  // O-   W    W    H    W    W    H    W    W    S      // Octave lower, (W)hole-step, (H)alf-step
  { CN3, CN4, DN4, EN4, FN4, GN4, FN4, EN4, DN4, CN4 },  // C
  { CS3, CS4, DS4, FN4, FS4, GS4, FS4, FN4, DS4, CS4 },  // C#
  { DN3, DN4, EN4, FS4, GN4, AN4, GN4, FS4, EN4, DN4 },  // D
  { DS3, DS4, FN4, GN4, GS4, AS4, GS4, GN4, FN4, DS4 },  // D#
  { EN3, EN4, FS4, GS4, AN4, BN4, AN4, GS4, FS4, EN4 },  // E
  { FN3, FN4, GN4, AN4, AS4, CN5, AS4, AN4, GN4, FN4 },  // F
  { FS3, FS4, GS4, AS4, BN4, CS5, BN4, AS4, GS4, FS4 },  // F#
  { GN3, GN4, AN4, BN4, CN5, DN5, CN5, BN4, AN4, GN4 },  // G
  { GS3, GS4, AS4, CN5, CS5, DS5, CS5, CN5, AS4, GS4 },  // G#
  { AN3, AN4, BN4, CS5, DN5, EN5, DN5, CS5, BN4, AN4 },  // A
  { AS3, AS4, CN5, DN5, DS5, FN5, DS5, DN5, CN5, AS4 },  // A#
  { BN3, BN4, CS5, DS5, EN5, FS5, EN5, DS5, CS5, BN4 }   // B
};

void setup() {
  Serial.begin(115200);
  Serial.println();
  delay(3000); // I do not know why Arduino needs a long pause here

  for (byte j = 0; j < scales; j++) {
    // Serial.print(scale[scales][0]);
    if (j < 11)
      Serial.print(" ");  // alignment
    Serial.print(j + 1);
    Serial.print(" of ");
    Serial.print(scales);
    Serial.print(" scales in fifths: ");

    for (byte i = 0; i < notes; i++) {
      Serial.print(i);
      if (i == 0 || i == 9)  // first and last note in scale
        duration = dur * 2;  // double note duration
      else
        duration = dur;
      tone(spkr_pin, scale[j][i], duration);
      delay(duration);
    }
    noTone(spkr_pin);  // end tone
    Serial.println();
  }
}

void loop() {}