Custom-MIDI-Sender.ino

Custom-MIDI-Sender

This is an example that demonstrates how to extend the library using your own MIDI Senders. It implements functionality similar to the built-in DigitalNoteSender class, but with support for different on and off velocities.

See also

MIDI Senders for different kinds of MIDI senders to start from.

Boards:

AVR, AVR USB, Due, Nano 33, Teensy 3.x, ESP32

Connections

• 5: momentary push button (to ground)

The internal pull-up resistor for the button will be enabled automatically.

Behavior

• When the button on pin 5 is pressed, a MIDI Note On message is sent for note C4 with velocity 0x40.
• When the button on pin 5 is released, a MIDI Note Off message is sent for note C4 with velocity 0x10.

Mapping

Select the Arduino as a custom MIDI controller in your DAW, and use the MIDI learn option to assign the button to a function.

Written by PieterP, 2020-04-18
https://github.com/tttapa/Control-Surface

 
#include <Control_Surface.h>
 
USBMIDI_Interface midi;
 
// A custom sender to use later. It has to declare two methods:
// - sendOn(MIDIAddress): will be called when the button is pressed
// - sendOff(MIDIAddress): will be called when the button is released
// Other types of senders need to implement different methods.
// For example, a continuous CC sender just has a send(value, address)
// method.
class CustomNoteSender {
  public:
    CustomNoteSender(uint8_t onVelocity, uint8_t offVelocity)
      : onVelocity(onVelocity), offVelocity(offVelocity) {}
 
    void sendOn(MIDIAddress address) {
      Control_Surface.sendNoteOn(address, onVelocity);
    }
 
    void sendOff(MIDIAddress address) {
      Control_Surface.sendNoteOff(address, offVelocity);
    }
 
  private:
    uint8_t onVelocity, offVelocity;
};
 
// Now tell the MIDIButton class template (included with the Control
// Surface library) that it has to use your custom sender class.
//
// We wrap it in another class so we can easily construct it later, 
// without having to write `MIDIButton<CustomNoteSender>` all the time,
// and so we have more control over the constructor arguments.
// The colon (:) indicates inheritance.
struct CustomNoteButton : MIDIButton<CustomNoteSender> {
  // Constructor
  CustomNoteButton(pin_t pin, MIDIAddress address, 
                   uint8_t onVelocity, uint8_t offVelocity)
    : MIDIButton(pin, address, {onVelocity, offVelocity}) {}
  //  ^~~~~~~~~~ Initialization of the base class MIDIButton
};
 
using namespace MIDI_Notes;
 
// Now we can instantiate an object of our custom class.
// The four arguments match the ones of the CustomNoteButton
// constructor we wrote a couple of lines back.
CustomNoteButton button = {
  5,            // button pin
  note(C, 4),   // MIDI address
  0x40,         // on velocity
  0x10,         // off velocity
};
 
void setup() {
  Control_Surface.begin();
}
 
void loop() {
  Control_Surface.loop();
}