How do I convert this older sketch to run MIDI over USB?

I do feel like an idiot today. I thought I had this figured out how to get this to send midi over USB on a Leonardo but it's not working. I'm pasting in the original code from Notes and Volts. I'm guessing that I'm missing something obvious. Is there a way to convert this to run USB midi on a Leonardo?

#include <MIDI.h>
#include "Controller.h"
#include <MIDIUSB.h>


/*************************************************************
  MIDI CONTROLLER

  by Notes and Volts
  www.notesandvolts.com

  Version 1.2 **Arduino UNO ONLY!**
 *************************************************************/

MIDI_CREATE_DEFAULT_INSTANCE();

//************************************************************
//***SET THE NUMBER OF CONTROLS USED**************************
//************************************************************
//---How many buttons are connected directly to pins?---------
byte NUMBER_BUTTONS = 0;
//---How many potentiometers are connected directly to pins?--
byte NUMBER_POTS = 0;
//---How many buttons are connected to a multiplexer?---------
byte NUMBER_MUX_BUTTONS = 0;
//---How many potentiometers are connected to a multiplexer?--
byte NUMBER_MUX_POTS = 0;
//************************************************************

//***ANY MULTIPLEXERS? (74HC4067)************************************
//MUX address pins must be connected to Arduino UNO pins 2,3,4,5
//A0 = PIN2, A1 = PIN3, A2 = PIN4, A3 = PIN5
//*******************************************************************
//Mux NAME (OUTPUT PIN, , How Many Mux Pins?(8 or 16) , Is It Analog?);


//Mux M1(10, 16, false); //Digital multiplexer on Arduino pin 10
//Mux M2(A5, 8, true); //Analog multiplexer on Arduino analog pin A0
//*******************************************************************


//***DEFINE DIRECTLY CONNECTED POTENTIOMETERS************************
//Pot (Pin Number, Command, CC Control, Channel Number)
//**Command parameter is for future use**

//Pot PO1(A0, 0, 1, 1);
//Pot PO2(A1, 0, 10, 1);
//Pot PO3(A2, 0, 22, 1);
//Pot PO4(A3, 0, 118, 1);
//Pot PO5(A4, 0, 30, 1);
//Pot PO6(A5, 0, 31, 1);
//*******************************************************************
//Add pots used to array below like this->  Pot *POTS[] {&PO1, &PO2, &PO3, &PO4, &PO5, &PO6};
Pot *POTS[] {};
//*******************************************************************


//***DEFINE DIRECTLY CONNECTED BUTTONS*******************************
//Button (Pin Number, Command, Note Number, Channel, Debounce Time)
//** Command parameter 0=NOTE  1=CC  2=Toggle CC **

//Button BU1(2, 0, 60, 1, 5 );
//Button BU2(3, 0, 61, 1, 5 );
//Button BU3(4, 0, 62, 1, 5 );
//Button BU4(5, 0, 63, 1, 5 );
//Button BU5(6, 0, 64, 1, 5 );
//Button BU6(7, 0, 65, 1, 5 );
//Button BU7(8, 1, 64, 1, 5 );
//Button BU8(9, 2, 64, 1, 5 );
//*******************************************************************
//Add buttons used to array below like this->  Button *BUTTONS[] {&BU1, &BU2, &BU3, &BU4, &BU5, &BU6, &BU7, &BU8};
Button *BUTTONS[] {};
//*******************************************************************


//***DEFINE BUTTONS CONNECTED TO MULTIPLEXER*************************
//Button::Button(Mux mux, byte muxpin, byte command, byte value, byte channel, byte debounce)
//** Command parameter 0=NOTE  1=CC  2=Toggle CC **

//Button MBU1(M1, 0, 0, 70, 1, 5);
//Button MBU2(M1, 1, 1, 71, 1, 5);
//Button MBU3(M1, 2, 2, 72, 1, 5);
//Button MBU4(M1, 3, 0, 73, 1, 5);
//Button MBU5(M1, 4, 0, 74, 1, 5);
//Button MBU6(M1, 5, 0, 75, 1, 5);
//Button MBU7(M1, 6, 0, 76, 1, 5);
//Button MBU8(M1, 7, 0, 77, 1, 5);
//Button MBU9(M1, 8, 0, 78, 1, 5);
//Button MBU10(M1, 9, 0, 79, 1, 5);
//Button MBU11(M1, 10, 0, 80, 1, 5);
//Button MBU12(M1, 11, 0, 81, 1, 5);
//Button MBU13(M1, 12, 0, 82, 1, 5);
//Button MBU14(M1, 13, 0, 83, 1, 5);
//Button MBU15(M1, 14, 0, 84, 1, 5);
//Button MBU16(M1, 15, 0, 85, 1, 5);
//*******************************************************************
////Add multiplexed buttons used to array below like this->  Button *MUXBUTTONS[] {&MBU1, &MBU2, &MBU3, &MBU4, &MBU5, &MBU6.....};
Button *MUXBUTTONS[] {};

//*******************************************************************


//***DEFINE POTENTIOMETERS CONNECTED TO MULTIPLEXER*******************
//Pot::Pot(Mux mux, byte muxpin, byte command, byte control, byte channel)
//**Command parameter is for future use**

//Pot MPO1(M2, 0, 0, 1, 1);
//Pot MPO2(M2, 1, 0, 7, 1);
//Pot MPO3(M2, 2, 0, 50, 1);
//Pot MPO4(M2, 3, 0, 55, 2);
//Pot MPO5(M2, 4, 0, 50, 1);
//Pot MPO6(M2, 5, 0, 55, 2);
//Pot MPO7(M2, 6, 0, 50, 1);
//Pot MPO8(M2, 7, 0, 55, 2);
//Pot MPO9(M2, 8, 0, 50, 1);
//Pot MPO10(M2, 9, 0, 55, 2);
//Pot MPO11(M2, 10, 0, 50, 1);
//Pot MPO12(M2, 11, 0, 55, 2);
//Pot MPO13(M2, 12, 0, 50, 1);
//Pot MPO14(M2, 13, 0, 55, 2);
//Pot MPO15(M2, 14, 0, 50, 1);
//Pot MPO16(M2, 15, 0, 55, 2);
//*******************************************************************
//Add multiplexed pots used to array below like this->  Pot *MUXPOTS[] {&MPO1, &MPO2, &MPO3, &MPO4, &MPO5, &MPO6.....};
Pot *MUXPOTS[] {};
//*******************************************************************


void setup() {
  MIDI.begin(MIDI_CHANNEL_OFF);
}

void loop() {
  if (NUMBER_BUTTONS != 0) updateButtons();
  if (NUMBER_POTS != 0) updatePots();
  if (NUMBER_MUX_BUTTONS != 0) updateMuxButtons();
  if (NUMBER_MUX_POTS != 0) updateMuxPots();
}


//*****************************************************************
void updateButtons() {

  // Cycle through Button array
  for (int i = 0; i < NUMBER_BUTTONS; i = i + 1) {
    byte message = BUTTONS[i]->getValue();

    //  Button is pressed
    if (message == 0) {
      switch (BUTTONS[i]->Bcommand) {
        case 0: //Note
          MIDI.sendNoteOn(BUTTONS[i]->Bvalue, 127, BUTTONS[i]->Bchannel);
          break;
        case 1: //CC
          MIDI.sendControlChange(BUTTONS[i]->Bvalue, 127, BUTTONS[i]->Bchannel);
          break;
        case 2: //Toggle
          if (BUTTONS[i]->Btoggle == 0) {
            MIDI.sendControlChange(BUTTONS[i]->Bvalue, 127, BUTTONS[i]->Bchannel);
            BUTTONS[i]->Btoggle = 1;
          }
          else if (BUTTONS[i]->Btoggle == 1) {
            MIDI.sendControlChange(BUTTONS[i]->Bvalue, 0, BUTTONS[i]->Bchannel);
            BUTTONS[i]->Btoggle = 0;
          }
          break;
      }
    }

    //  Button is not pressed
    if (message == 1) {
      switch (BUTTONS[i]->Bcommand) {
        case 0:
          MIDI.sendNoteOff(BUTTONS[i]->Bvalue, 0, BUTTONS[i]->Bchannel);
          break;
        case 1:
          MIDI.sendControlChange(BUTTONS[i]->Bvalue, 0, BUTTONS[i]->Bchannel);
          break;
      }
    }
  }
}
//*******************************************************************
void updateMuxButtons() {

  // Cycle through Mux Button array
  for (int i = 0; i < NUMBER_MUX_BUTTONS; i = i + 1) {

    MUXBUTTONS[i]->muxUpdate();
    byte message = MUXBUTTONS[i]->getValue();

    //  Button is pressed
    if (message == 0) {
      switch (MUXBUTTONS[i]->Bcommand) {
        case 0: //Note
          MIDI.sendNoteOn(MUXBUTTONS[i]->Bvalue, 127, MUXBUTTONS[i]->Bchannel);
          break;
        case 1: //CC
          MIDI.sendControlChange(MUXBUTTONS[i]->Bvalue, 127, MUXBUTTONS[i]->Bchannel);
          break;
        case 2: //Toggle
          if (MUXBUTTONS[i]->Btoggle == 0) {
            MIDI.sendControlChange(MUXBUTTONS[i]->Bvalue, 127, MUXBUTTONS[i]->Bchannel);
            MUXBUTTONS[i]->Btoggle = 1;
          }
          else if (MUXBUTTONS[i]->Btoggle == 1) {
            MIDI.sendControlChange(MUXBUTTONS[i]->Bvalue, 0, MUXBUTTONS[i]->Bchannel);
            MUXBUTTONS[i]->Btoggle = 0;
          }
          break;
      }
    }
    //  Button is not pressed
    if (message == 1) {
      switch (MUXBUTTONS[i]->Bcommand) {
        case 0:
          MIDI.sendNoteOff(MUXBUTTONS[i]->Bvalue, 0, MUXBUTTONS[i]->Bchannel);
          break;
        case 1:
          MIDI.sendControlChange(MUXBUTTONS[i]->Bvalue, 0, MUXBUTTONS[i]->Bchannel);
          break;
      }
    }
  }
}
//***********************************************************************
void updatePots() {
  for (int i = 0; i < NUMBER_POTS; i = i + 1) {
    byte potmessage = POTS[i]->getValue();
    if (potmessage != 255) MIDI.sendControlChange(POTS[i]->Pcontrol, potmessage, POTS[i]->Pchannel);
  }
}
//***********************************************************************
void updateMuxPots() {
  for (int i = 0; i < NUMBER_MUX_POTS; i = i + 1) {
    MUXPOTS[i]->muxUpdate();
    byte potmessage = MUXPOTS[i]->getValue();
    if (potmessage != 255) MIDI.sendControlChange(MUXPOTS[i]->Pcontrol, potmessage, MUXPOTS[i]->Pchannel);
  }
}

I'd recommend using the Control Surface library I maintain instead. It has a common API for all MIDI transports, including MIDI over USB and normal serial MIDI.

You can find a "Getting Started" tutorial here. It explains how to use potentiometers and multiplexers. Adding buttons is really easy as well, as shown in the CCButton example.


To answer your original question: the issue is that the MIDIUSB library only implements the MIDIUSB transport, it has no high-level functions for sending and receiving MIDI events, it only sends and receives USB packets containing MIDI data, without actually constructing or parsing those packets. (It doesn't have high-level functions like sendControlChange, for example.)

Constructing the MIDI messages is relatively straightforward, and explained in the MIDIUSB spec: https://www.usb.org/sites/default/files/midi10.pdf
The relevant pages are 16 and 17. Compare this to the examples that come with the MIDIUSB library.

There is a wrapper for the MIDI.h library you're using to make it work with MIDI over USB, but I have never used it.

If you're interested in the MIDI protocol and you want to learn more about it, implementing the necessary functions yourself is a good exercise. Otherwise, I'd recommend using an existing library with MIDI over USB support, like Control Surface.

Pieter

wordsushi:
Oh hey, you know those moments when the sheer act of writing and posting something brings you to that a-ha moment. Well, I realized what the answer was just after I posted my question, so I'm deleting it as to not waste anyone else's time. I apologize for the inconvenience.
Thanks,
M

Well, in that case, the correct thing to do is not to delete your original message. This forum is used as a future reference for other hobbyists as well, who might benefit from the information in both the questions and the answers. Without your original question, my answer doesn't make much sense ...

Hi PieterP,
Thanks for your response. I 'm such a noob, I couldn't find the "delete" button, but as it turned out, I didn't need to since I realized I hadn't fixed my problem and then reinstated my original question. However, your suggestion of looking towards the Control Surface library may indeed help me solve this problem. I'll check it out and hopefully even an idiot like myself can understand it enough to get it working. Thanks!

Ok, just a few minutes tinkering with the Control Surface library and I think I can parse this. I have one test fader working sending midi control signals over USB, so I'll continue to dig in and try to figure this out, but you're right, this does seem a lot more straightforward. Thanks again Pieter!

PieterP,
First of all I didn't realize until this morning that you are the creator of the Control Surface library. Thank you, Sir! My interest in Arduino is fully about creating midi control surfaces so I plan on digging deep into Control Surface to see what midi magic I can unlock. Very excited about finding this.