In PComp class Billy and I make a Music Instrument that can adjust the pitch by pressing and tapping. Check this out!

#include "pitches.h"

int lastButtonState = LOW;
boolean switchIsOn = false;

const int threshold = 10;
const int speakerPinNum = 8;
const int noteDuration = 20;

const int potenPinNum = 5;
int volumeAnalogValue = 0;
int volume = 0;

const int potPinNum = 2;
float saveNote;

int note[] = {
  NOTE_C4, NOTE_E4};

void setup() {
  Serial.begin(9600);
  saveNote = note[1];

}

void loop() {

  int buttonState = digitalRead(2);

  if (buttonState != lastButtonState) {
    if (buttonState == HIGH) {
      switchIsOn = !switchIsOn;
    }
  }

  lastButtonState = buttonState;

  if (switchIsOn == true) {

    int pitchRead = analogRead(0);
    int noteRead = analogRead(1);

    float pitch = map(pitchRead, 0, 950, 0, 100);

    if (pitch > 0) {
      note[1] += pitch;
    } 
    else {
      note[1] = saveNote;
    }

    Serial.print(pitch);
    Serial.print(" ");
    Serial.println(noteRead);

    if(noteRead > threshold) {
      tone(speakerPinNum, note[1], noteDuration);
    } 
  }
}

As for my review for this on Sunday, I made a basic music kit that you can control on/off, volumes, pitches(higher/lower), and tempo. But since it’s a single-note playing machine instead of templates/clip of music triggered one, it makes no difference with the changes of tempo.

And thanks to almighty Moon! I got the idea of setting button-“released” as the command to adjust pitches, so that pitches won’t go crazy because of the unmeasurable amount/time of button-“pressed” when you press the button. Thank you Moon 😀

What I want to do next–

1. make chords (office hour w/ resident booked!)
2. play continuous clips instead of single notes
3. be creative! not just pressing buttons… not interesting at all… go go go!

And here’s the code.

#include "pitches.h"

int lastButtonState = LOW;
boolean switchIsOn = false;

const int threshold = 600;
const int speakerPinNum = 8;
const int switchPinNum = 2;
const int higherPitchPinNum = 4;
const int lowerPitchPinNum = 3;

int pre_higherPitchRead = 0;
int pre_lowerPitchRead = 0;

const int tempoPinNum = 0;
const int noteGPinNum = 1;
const int noteEPinNum = 2;
const int noteCPinNum = 3;

const int noteDuration = 20;

int saveNote[3];
int note[] = {NOTE_C4, NOTE_E4, NOTE_G4};

void setup() {
  Serial.begin(9600);

  // save the original notes
  for (int i=0; i<3; i++) {
    saveNote[i] = note[i];
  }
}

void loop() {

  // on-off switch setting
  int buttonState = digitalRead(switchPinNum);
  if (buttonState != lastButtonState) {
    if (buttonState == HIGH) {
      switchIsOn = !switchIsOn;
    }
  }
  lastButtonState = buttonState;

  // read different notes
  int noteCRead = analogRead(noteCPinNum);
  int noteERead = analogRead(noteEPinNum);
  int noteGRead = analogRead(noteGPinNum);

  // set up duration of notes
  int tempoRead = analogRead(tempoPinNum);
  int tempo = map(tempoRead, 0, 1023, 5, 100);

  // press buttons to make notes go higher/lower 
  int higherPitchRead = digitalRead(higherPitchPinNum);
  int lowerPitchRead = digitalRead(lowerPitchPinNum);

  // when switch is on
  if (switchIsOn == true) {

    Serial.print(tempo);
    Serial.print("  ");

    // make notes go higher or lower
    for (int i=0; i<3; i++) {
      if (higherPitchRead == LOW && pre_higherPitchRead == HIGH) {
        note[i] *= 2;
      }
     if (lowerPitchRead == LOW && pre_lowerPitchRead == HIGH) {
        note[i] /= 2;
      }
      note[0] = constrain(note[0], 32, 4192);
      note[1] = constrain(note[1], 41, 5280);
      note[2] = constrain(note[2], 49, 6272);
    }

    // make sounds!
    if(noteCRead < threshold && noteERead < threshold && noteGRead < threshold) {
      for (int i=0; i<3; i++) {
        tone(speakerPinNum, note[i], tempo);
      }
    } else if(noteCRead < threshold && noteERead < threshold) {
      tone(speakerPinNum, note[0], tempo);
      tone(speakerPinNum, note[1], tempo);
    } else if(noteCRead < threshold && noteGRead < threshold) {
      tone(speakerPinNum, note[0], tempo);
      tone(speakerPinNum, note[2], tempo);
    } else if(noteGRead < threshold && noteERead < threshold) {
      tone(speakerPinNum, note[2], tempo);
      tone(speakerPinNum, note[3], tempo);
    } else if(noteCRead < threshold) {
      tone(speakerPinNum, note[0], tempo);
    } else if(noteERead < threshold) {
      tone(speakerPinNum, note[1], tempo);
    } else if(noteGRead < threshold) {
      tone(speakerPinNum, note[2], tempo);
    }

    Serial.print(note[0]);
    Serial.print(" ");
    Serial.print(note[1]);
    Serial.print(" ");
    Serial.print(note[2]);
    Serial.print(" ");
    Serial.println(" ");

  } else {
    for (int i=0; i<3; i++) {      // when swtich-off
      note[i] = saveNote[i];       // restore the original notes
    }
  }

  // remember the previouse higher/lower pitch buttons status
  pre_higherPitchRead = higherPitchRead;
  pre_lowerPitchRead = lowerPitchRead;
}