function onMIDIMessage (message) {
    var frequency = midiNoteToFrequency(message.data[1]);
 
    if (message.data[0] === 144 && message.data[2] > 0) {
        playNote(frequency);
    }
 
    if (message.data[0] === 128 || message.data[2] === 0) {
        stopNote(frequency);
    }
}

function onMIDIMessage (message) {
    var frequency = midiNoteToFrequency(message.data[1]);
 
    if (message.data[0] === 144 && message.data[2] > 0) {
        playNote(frequency);
    }
 
    if (message.data[0] === 128 || message.data[2] === 0) {
        stopNote(frequency);
    }
}

#include <Adafruit_CircuitPlayground.h>
#include "MIDIUSB.h"

bool leftButtonPressed;
bool rightButtonPressed;
bool noteOneOn;
bool noteTwoOn;

void setup() {
  CircuitPlayground.begin();
}

void loop() {
  
  leftButtonPressed = CircuitPlayground.leftButton();
  rightButtonPressed = CircuitPlayground.rightButton();

  //Control note one based on left button
  if (leftButtonPressed && !noteOneOn) {
    noteOn(0, 60, 100);
    noteOneOn = true;
  } 
  else if (!leftButtonPressed && noteOneOn) {
    noteOff(0, 60, 100);
    noteOneOn = false;
  }

  //Control note two based on right button
  if (rightButtonPressed && !noteTwoOn) {
    noteOn(0, 64, 100);
    noteTwoOn = true;
  } 
  else if (!rightButtonPressed && noteTwoOn){
    noteOff(0, 64, 100);
    noteTwoOn = false;
  }

  //Use light sensor as a modulation control
  int value = CircuitPlayground.lightSensor();  //value from 0-1024
  value = value/8;  //scale to 0-127 for MIDI CC
  controlChange(0, 1, value); //send as MIDI modulation control
  
}

void noteOn(byte channel, byte pitch, byte velocity) {
  midiEventPacket_t noteOn = {0x09, 0x90 | channel, pitch, velocity};
  MidiUSB.sendMIDI(noteOn);
}

void noteOff(byte channel, byte pitch, byte velocity) {
  midiEventPacket_t noteOff = {0x08, 0x80 | channel, pitch, velocity};
  MidiUSB.sendMIDI(noteOff);
}

void controlChange(byte channel, byte control, byte value) {
  midiEventPacket_t event = {0x0B, 0xB0 | channel, control, value};
  MidiUSB.sendMIDI(event);
}

#include <Adafruit_CircuitPlayground.h>
#include "MIDIUSB.h"

bool leftButtonPressed;
bool rightButtonPressed;
bool noteOneOn;
bool noteTwoOn;

void setup() {
  CircuitPlayground.begin();
}

void loop() {
  
  leftButtonPressed = CircuitPlayground.leftButton();
  rightButtonPressed = CircuitPlayground.rightButton();

  //Control note one based on left button
  if (leftButtonPressed && !noteOneOn) {
    noteOn(0, 60, 100);
    noteOneOn = true;
  } 
  else if (!leftButtonPressed && noteOneOn) {
    noteOff(0, 60, 100);
    noteOneOn = false;
  }

  //Control note two based on right button
  if (rightButtonPressed && !noteTwoOn) {
    noteOn(0, 64, 100);
    noteTwoOn = true;
  } 
  else if (!rightButtonPressed && noteTwoOn){
    noteOff(0, 64, 100);
    noteTwoOn = false;
  }

  //Use light sensor as a modulation control
  int value = CircuitPlayground.lightSensor();  //value from 0-1024
  value = value/8;  //scale to 0-127 for MIDI CC
  controlChange(0, 1, value); //send as MIDI modulation control
  
}

void noteOn(byte channel, byte pitch, byte velocity) {
  midiEventPacket_t noteOn = {0x09, 0x90 | channel, pitch, velocity};
  MidiUSB.sendMIDI(noteOn);
}

void noteOff(byte channel, byte pitch, byte velocity) {
  midiEventPacket_t noteOff = {0x08, 0x80 | channel, pitch, velocity};
  MidiUSB.sendMIDI(noteOff);
}

void controlChange(byte channel, byte control, byte value) {
  midiEventPacket_t event = {0x0B, 0xB0 | channel, control, value};
  MidiUSB.sendMIDI(event);
}

/*********************************************************************
 * Simple MIDI controller for the Feather Bluefruit NRF52
  uses potentiometers connected to pins 2(A0) & 3(A1)
  + four momentary pushbuttons connected to pins 16, 15, 7, & 11

  Adafruit invests time and resources providing this open source code,
  please support Adafruit and open-source hardware by purchasing
  products from Adafruit!

  MIT license
*********************************************************************/

/* For BLE MIDI Setup
   https://learn.adafruit.com/wireless-untztrument-using-ble-midi/overview
*/

#include <bluefruit.h>
#include <MIDI.h>

BLEDis bledis;
BLEMidi blemidi;

// Create a new instance of the Arduino MIDI Library, and attach BluefruitLE MIDI as the transport.
MIDI_CREATE_BLE_INSTANCE(blemidi);

int buttons[4] = {16, 15, 7, 11}; //pin numbers for each attached button
int notes[4] = {57, 62, 66, 69};  //note each button will play
bool noteStates[4] = {false};     //keep track of the play state of each note

int modPot = 2;  //analog pin A0
int pitchPot = 3;  //analog pin A1
int lastModVal;
int lastPitchVal;

void setup(){
  
  Serial.begin(115200);
  while ( !Serial ) delay(10);   // for nrf52840 with native usb

  //set input modes for buttons
  for (int i = 0; i < 4; i++) {
    pinMode(buttons[i], INPUT_PULLUP);
  }

  Serial.println("Adafruit Bluefruit52 MIDI over Bluetooth LE Example");

  // Config the peripheral connection with maximum bandwidth
  Bluefruit.configPrphBandwidth(BANDWIDTH_MAX);

  Bluefruit.begin();
  Bluefruit.setName("Bluefruit52 MIDI");
  Bluefruit.setTxPower(4);

  // Setup the on board blue LED to be enabled on CONNECT
  Bluefruit.autoConnLed(true);

  // Configure and Start Device Information Service
  bledis.setManufacturer("Adafruit Industries");
  bledis.setModel("Bluefruit Feather52");
  bledis.begin();

  // Initialize MIDI, and listen to all MIDI channels, will also call blemidi service's begin()
  MIDI.begin(MIDI_CHANNEL_OMNI);

  // Attach the handleNoteOn function to the MIDI Library. It will
  // be called whenever the Bluefruit receives MIDI Note On messages.
  MIDI.setHandleNoteOn(handleNoteOn);

  // Do the same for MIDI Note Off messages.
  MIDI.setHandleNoteOff(handleNoteOff);

  // Set up and start advertising
  startAdv();

  // Start MIDI read loop
  Scheduler.startLoop(midiRead);
}

void startAdv(void){
  
  // Set General Discoverable Mode flag
  Bluefruit.Advertising.addFlags(BLE_GAP_ADV_FLAGS_LE_ONLY_GENERAL_DISC_MODE);

  // Advertise TX Power
  Bluefruit.Advertising.addTxPower();

  // Advertise BLE MIDI Service
  Bluefruit.Advertising.addService(blemidi);

  // Secondary Scan Response packet (optional)
  Bluefruit.ScanResponse.addName();

  //Start Advertising
  Bluefruit.Advertising.restartOnDisconnect(true);
  Bluefruit.Advertising.setInterval(32, 244);    // in unit of 0.625 ms
  Bluefruit.Advertising.setFastTimeout(30);      // number of seconds in fast mode
  Bluefruit.Advertising.start(0);                // 0 = Don't stop advertising after n seconds
}

void handleNoteOn(byte channel, byte pitch, byte velocity){
  
  // Log when a note is pressed.
  Serial.printf("Note on: channel = %d, pitch = %d, velocity - %d", channel, pitch, velocity);
  Serial.println();
}

void handleNoteOff(byte channel, byte pitch, byte velocity){
  
  // Log when a note is released.
  Serial.printf("Note off: channel = %d, pitch = %d, velocity - %d", channel, pitch, velocity);
  Serial.println();
}

void loop(){
  
  // Don't continue if we aren't connected.
  if (! Bluefruit.connected()) {
    return;
  }
  // Don't continue if the connected device isn't ready to receive messages.
  if (! blemidi.notifyEnabled()) {
    return;
  }

  //check pot values
  int modVal = analogRead(modPot);
  int pitchVal = analogRead(pitchPot);
  pitchVal = map(pitchVal, 0, 1023, -8000, 8000);
  modVal = modVal / 8;

  //send new mod value if it has changed
  if (lastModVal != modVal) {
    Serial.print("modWheel = ");
    Serial.println(modVal);
    MIDI.sendControlChange(1, modVal, 1);
    lastModVal = modVal;
  }

  //send new pitch value if it has changed
  if (lastPitchVal != pitchVal) {
    Serial.print("pitchBend = ");
    Serial.println(pitchVal);
    MIDI.sendPitchBend(pitchVal, 1); //pot value sent as pitch bend
    lastPitchVal = pitchVal;
  }

  //check all buttons
  for (int i = 0; i < 4; i++) {

    bool buttonPressed = !digitalRead(buttons[i]);

    //send note on if button pressed and note is off
    if (buttonPressed && !noteStates[i]) {
      Serial.print("Button pressed: ");
      Serial.println(i);
      MIDI.sendNoteOn(notes[i], 100, 1);
      noteStates[i] = true;
    }
    //send note off if button released and note is on
    else if (!buttonPressed && noteStates[i]) {
      Serial.print("Button released: ");
      Serial.println(i);
      MIDI.sendNoteOff(notes[i], 100, 1);
      noteStates[i] = false;
    }
  }

  delay(100);
}

void midiRead(){
  
  // Don't continue if we aren't connected.
  if (! Bluefruit.connected()) {
    return;
  }

  // Don't continue if the connected device isn't ready to receive messages.
  if (! blemidi.notifyEnabled()) {
    return;
  }

  // read any new MIDI messages
  MIDI.read();
}

/*********************************************************************
 * Simple MIDI controller for the Feather Bluefruit NRF52
  uses potentiometers connected to pins 2(A0) & 3(A1)
  + four momentary pushbuttons connected to pins 16, 15, 7, & 11

  Adafruit invests time and resources providing this open source code,
  please support Adafruit and open-source hardware by purchasing
  products from Adafruit!

  MIT license
*********************************************************************/

/* For BLE MIDI Setup
   https://learn.adafruit.com/wireless-untztrument-using-ble-midi/overview
*/

#include <bluefruit.h>
#include <MIDI.h>

BLEDis bledis;
BLEMidi blemidi;

// Create a new instance of the Arduino MIDI Library, and attach BluefruitLE MIDI as the transport.
MIDI_CREATE_BLE_INSTANCE(blemidi);

int buttons[4] = {16, 15, 7, 11}; //pin numbers for each attached button
int notes[4] = {57, 62, 66, 69};  //note each button will play
bool noteStates[4] = {false};     //keep track of the play state of each note

int modPot = 2;  //analog pin A0
int pitchPot = 3;  //analog pin A1
int lastModVal;
int lastPitchVal;

void setup(){
  
  Serial.begin(115200);
  while ( !Serial ) delay(10);   // for nrf52840 with native usb

  //set input modes for buttons
  for (int i = 0; i < 4; i++) {
    pinMode(buttons[i], INPUT_PULLUP);
  }

  Serial.println("Adafruit Bluefruit52 MIDI over Bluetooth LE Example");

  // Config the peripheral connection with maximum bandwidth
  Bluefruit.configPrphBandwidth(BANDWIDTH_MAX);

  Bluefruit.begin();
  Bluefruit.setName("Bluefruit52 MIDI");
  Bluefruit.setTxPower(4);

  // Setup the on board blue LED to be enabled on CONNECT
  Bluefruit.autoConnLed(true);

  // Configure and Start Device Information Service
  bledis.setManufacturer("Adafruit Industries");
  bledis.setModel("Bluefruit Feather52");
  bledis.begin();

  // Initialize MIDI, and listen to all MIDI channels, will also call blemidi service's begin()
  MIDI.begin(MIDI_CHANNEL_OMNI);

  // Attach the handleNoteOn function to the MIDI Library. It will
  // be called whenever the Bluefruit receives MIDI Note On messages.
  MIDI.setHandleNoteOn(handleNoteOn);

  // Do the same for MIDI Note Off messages.
  MIDI.setHandleNoteOff(handleNoteOff);

  // Set up and start advertising
  startAdv();

  // Start MIDI read loop
  Scheduler.startLoop(midiRead);
}

void startAdv(void){
  
  // Set General Discoverable Mode flag
  Bluefruit.Advertising.addFlags(BLE_GAP_ADV_FLAGS_LE_ONLY_GENERAL_DISC_MODE);

  // Advertise TX Power
  Bluefruit.Advertising.addTxPower();

  // Advertise BLE MIDI Service
  Bluefruit.Advertising.addService(blemidi);

  // Secondary Scan Response packet (optional)
  Bluefruit.ScanResponse.addName();

  //Start Advertising
  Bluefruit.Advertising.restartOnDisconnect(true);
  Bluefruit.Advertising.setInterval(32, 244);    // in unit of 0.625 ms
  Bluefruit.Advertising.setFastTimeout(30);      // number of seconds in fast mode
  Bluefruit.Advertising.start(0);                // 0 = Don't stop advertising after n seconds
}

void handleNoteOn(byte channel, byte pitch, byte velocity){
  
  // Log when a note is pressed.
  Serial.printf("Note on: channel = %d, pitch = %d, velocity - %d", channel, pitch, velocity);
  Serial.println();
}

void handleNoteOff(byte channel, byte pitch, byte velocity){
  
  // Log when a note is released.
  Serial.printf("Note off: channel = %d, pitch = %d, velocity - %d", channel, pitch, velocity);
  Serial.println();
}

void loop(){
  
  // Don't continue if we aren't connected.
  if (! Bluefruit.connected()) {
    return;
  }
  // Don't continue if the connected device isn't ready to receive messages.
  if (! blemidi.notifyEnabled()) {
    return;
  }

  //check pot values
  int modVal = analogRead(modPot);
  int pitchVal = analogRead(pitchPot);
  pitchVal = map(pitchVal, 0, 1023, -8000, 8000);
  modVal = modVal / 8;

  //send new mod value if it has changed
  if (lastModVal != modVal) {
    Serial.print("modWheel = ");
    Serial.println(modVal);
    MIDI.sendControlChange(1, modVal, 1);
    lastModVal = modVal;
  }

  //send new pitch value if it has changed
  if (lastPitchVal != pitchVal) {
    Serial.print("pitchBend = ");
    Serial.println(pitchVal);
    MIDI.sendPitchBend(pitchVal, 1); //pot value sent as pitch bend
    lastPitchVal = pitchVal;
  }

  //check all buttons
  for (int i = 0; i < 4; i++) {

    bool buttonPressed = !digitalRead(buttons[i]);

    //send note on if button pressed and note is off
    if (buttonPressed && !noteStates[i]) {
      Serial.print("Button pressed: ");
      Serial.println(i);
      MIDI.sendNoteOn(notes[i], 100, 1);
      noteStates[i] = true;
    }
    //send note off if button released and note is on
    else if (!buttonPressed && noteStates[i]) {
      Serial.print("Button released: ");
      Serial.println(i);
      MIDI.sendNoteOff(notes[i], 100, 1);
      noteStates[i] = false;
    }
  }

  delay(100);
}

void midiRead(){
  
  // Don't continue if we aren't connected.
  if (! Bluefruit.connected()) {
    return;
  }

  // Don't continue if the connected device isn't ready to receive messages.
  if (! blemidi.notifyEnabled()) {
    return;
  }

  // read any new MIDI messages
  MIDI.read();
}