School Project with arduino IDE

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1

Hello, I am currently working on a stem project making a midi piano out of arduino. I am having a hard time getting the code to work, but I'm not sure if its because of the MIDIUSB library or the code itself. Please help

#include <MIDIUSB.h> // Include the MIDIUSB library

#define NOTE_D 60 // MIDI note number for D4
#define NOTE_E 62 // MIDI note number for E4
#define NOTE_F 63 // MIDI note number for F4
#define NOTE_G 65 // MIDI note number for G4
#define MIDI_CHANNEL 1 // Define MIDI channel
#define MIDIUSB

const int notes[] = {NOTE_D, NOTE_E, NOTE_F, NOTE_G};
int lastNote = -1; // Store the last note played

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

void loop() {
  // Check for incoming MIDI messages
  while (available() > 0) {
    midiEventPacket_t event = read(); // Read a MIDI event
    handleMIDIEvent(event); // Handle the event if necessary
  }

  int keyVal = analogRead(A0); // Read from the analog pin
  Serial.println(keyVal);

  if (keyVal == 1023) {
    playNoteIfChanged(notes[0]); // D4
  } 
  else if (keyVal >= 990 && keyVal <= 1010) {
    playNoteIfChanged(notes[1]); // E4
  } 
  else if (keyVal >= 505 && keyVal <= 515) {
    playNoteIfChanged(notes[2]); // F4
  } 
  else if (keyVal >= 5 && keyVal <= 10) {
    playNoteIfChanged(notes[3]); // G4
  } 
  else {
    if (lastNote != -1) {
      sendNoteOff(lastNote); // Stop the last note
      lastNote = -1; // Reset last note
    }
  }
  delay(100); // Debounce delay
}

void handleMIDIEvent(midiEventPacket_t event) {
  if (event.header != 0) { // Check if there's a valid MIDI message
    Serial.print("MIDI Message: ");
    Serial.print(event.byte1, HEX); // Print the first byte of the MIDI message
    Serial.print(" ");
    Serial.print(event.byte2, HEX); // Print the second byte (note)
    Serial.print(" ");
    Serial.println(event.byte3, HEX); // Print the third byte (velocity)
  }
}

void playNoteIfChanged(byte note) {
  if (note != lastNote) {
    if (lastNote != -1) {
      sendNoteOff(lastNote); // Stop the last note before playing a new one
    }
    sendNoteOn(note); // Start the new note
    lastNote = note; // Update last note
  }
}

void sendNoteOn(byte note) {
  midiEventPacket_t event = {0x09 | (MIDI_CHANNEL - 1), note, 127}; // Note On message
  sendMIDI(event); // Send the MIDI message
}

void sendNoteOff(byte note) {
  midiEventPacket_t event = {0x08 | (MIDI_CHANNEL - 1), note, 0}; // Note Off message
  sendMIDI(event); // Send the MIDI message
}

void sendMIDI(midiEventPacket_t event) {
  MIDIUSB.send(event); // Correct way to send the MIDI event
  MIDIUSB.flush(); // Wait for all messages to be sent
}

uint32_t available() {
  return MIDIUSB.available(); // Return the number of available MIDI messages
}

midiEventPacket_t read() {
  return MIDIUSB.read(); // Read a MIDI event from USB
}
2

Hi @emilyreed ,

congrats for using code tags in your first post!

:wink:

Would you mind to describe the problem(s) you encountered ?

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3

Could you also describe/provide a diagram of how you have the Arduino set up to play the notes?

4

You must show your hardware, program and errors.

Does your error say something like this:

/tmp/build-Ksso2a/libraries/MIDIUSB/src/MIDIUSB.h:18:2: error: #error MIDIUSB can only be used with an USB MCU.
 #error MIDIUSB can only be used with an USB MCU.
  ^~~~~
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