5.Note-LED-PWM.ino

5.Note-LED-PWM

This example demonstrates the use of LEDs that respond to incoming MIDI note events by changing the brightness of an LED using PWM.

Boards: 🛈

AVR, AVR USB, Nano Every, Due, Nano 33 IoT, Nano 33 BLE, UNO R4, Pi Pico, Teensy 3.x

Connections

Connect an LED (+ current limiting resistor) to any PWM pin. Then change the pin number in the ledPin constant to match the pin with your LED connected.

Behavior

If a MIDI Note On event for note 0x3C (C4 or middle C) is sent, the LED will light up, with the brightness depending on the velocity.
If a Note Off event for that note is sent, the LED will turn off.
(A Note On event with a velocity of zero also counts as a Note Off event.)

Mapping

Route the MIDI output of a MIDI keyboard to the Arduino's MIDI input. Then play a middle C on the keyboard.

Written by PieterP, 2020-01-03
https://github.com/tttapa/Control-Surface

 
#include <Control_Surface.h> // Include the Control Surface library
 
// Instantiate a MIDI over USB interface.
USBMIDI_Interface midi;
 
const pin_t ledPin = LED_BUILTIN; // Change this to your PWM pin <------
 
// Instantiate the LED that will light up when middle C is playing
NoteLEDPWM led {
  ledPin,                        // Pin of the LED, must be PWM pin
  {MIDI_Notes::C[4], Channel_1}, // Note C4 on MIDI channel 1
};
 
void setup() {
  Control_Surface.begin(); // Initialize Control Surface
}
 
void loop() {
  Control_Surface.loop(); // Update the Control Surface
}