MIDI reader

midi_leds.ino

#include <MIDI.h>

#define NOTES 26
#define OCTAVE_LENGTH 12
#define BASELINE 43
#define CHANNELS 3

int latchPin1 = 8;
int clockPin1 = 12;
int dataPin1 = 11;

int latchPin2 = 9;
int clockPin2 = 6;
int dataPin2 = 7;

int g3 = 10;
int gSharp3 = 5;

byte notes[CHANNELS][NOTES];
byte dataArrayRED[8];
byte dataArrayGREEN[8];
byte dataArrayYELLOW[8];

MIDI_CREATE_DEFAULT_INSTANCE();

void handleNoteOn(byte channel, byte pitch, byte velocity) { 
    // ignore anything outside our range
    if (channel > 3 || (channel == 2 && pitch - OCTAVE_LENGTH - BASELINE >= NOTES) || (channel != 2 && pitch - BASELINE >= NOTES)) {
        return;
    }
    // set a new note on (channel 2 gets down an octave)
    if (channel == 2) {
        pitch -= OCTAVE_LENGTH;
    }
    notes[channel - 1][pitch - BASELINE] = 1;
    refreshLeds();
}

void handleNoteOff(byte channel, byte pitch, byte velocity) {
    // ignore anything outside our range
    if (channel > 3 || (channel == 2 && pitch - OCTAVE_LENGTH - BASELINE >= NOTES) || (channel != 2 &&  pitch - BASELINE >= NOTES)) {
        return;
    }
    // set a new note off (channel 2 gets down an octave)
    if (channel == 2) {
        pitch -= OCTAVE_LENGTH;
    }
    notes[channel - 1][pitch - BASELINE] = 0;
    refreshLeds();
}

void setup() {
    int i, j;
    
    MIDI.begin(MIDI_CHANNEL_OMNI);
    MIDI.setHandleNoteOn(handleNoteOn); 
    MIDI.setHandleNoteOff(handleNoteOff);
    pinMode(latchPin1, OUTPUT);
    pinMode(latchPin2, OUTPUT);
    pinMode(g3, OUTPUT);
    pinMode(gSharp3, OUTPUT);
    
    for (j = 0; j < CHANNELS; j++) {
        for (i = 0; i < NOTES; i++) {
            notes[j][i] = 0;
        }
    }
    
    dataArrayRED[0] = 0x01; //00000001
    dataArrayRED[1] = 0x02; //00000010
    dataArrayRED[2] = 0x04; //00000100
    dataArrayRED[3] = 0x08; //00001000
    dataArrayRED[4] = 0x10; //00010000
    dataArrayRED[5] = 0x20; //00100000
    dataArrayRED[6] = 0x40; //01000000
    dataArrayRED[7] = 0x80; //10000000
    
    dataArrayGREEN[0] = 0x01; //00000001
    dataArrayGREEN[1] = 0x02; //00000010
    dataArrayGREEN[2] = 0x04; //00000100
    dataArrayGREEN[3] = 0x08; //00001000
    dataArrayGREEN[4] = 0x10; //00010000
    dataArrayGREEN[5] = 0x20; //00100000
    dataArrayGREEN[6] = 0x40; //01000000
    dataArrayGREEN[7] = 0x80; //10000000
    
    dataArrayYELLOW[0] = 0x01; //00000001
    dataArrayYELLOW[1] = 0x02; //00000010
    dataArrayYELLOW[2] = 0x04; //00000100
    dataArrayYELLOW[3] = 0x08; //00001000
    dataArrayYELLOW[4] = 0x10; //00010000
    dataArrayYELLOW[5] = 0x20; //00100000
    dataArrayYELLOW[6] = 0x40; //01000000
    dataArrayYELLOW[7] = 0x80; //10000000
    
    digitalWrite(latchPin1, 0);
    shiftOut(dataPin1, clockPin1, 0x00);
    shiftOut(dataPin1, clockPin1, 0x00);
    digitalWrite(latchPin1, 1);
    digitalWrite(latchPin2, 0);
    shiftOut(dataPin2, clockPin2, 0x00);
    digitalWrite(latchPin2, 1);
    digitalWrite(g3, 0);
    digitalWrite(gSharp3, 0);
}

void loop() {
    MIDI.read();
}

void refreshLeds() {
    int i, j;
    byte dataRED = 0x00;
    byte dataGREEN = 0x00;
    byte dataYELLOW = 0x00;
    byte g3on = 0;
    byte gSharp3on = 0;
    
    for (j = 0; j < CHANNELS; j++) {
        for (i = 0; i < NOTES; i++) {
            if (i < 8) {
                if (notes[j][i]) {
                    dataRED |= dataArrayRED[i];
                }
            }
            else if (i < 16) {
                if (notes[j][i]) {
                    dataGREEN |= dataArrayGREEN[i % 8];
                }
            }
            else if (i < 24) {
                if (notes[j][i]) {
                    dataYELLOW |= dataArrayYELLOW[i % 8];
                }
            }
            else if (i == 24) {
                if (notes[j][i]) {
                    g3on = 1;
                }
            }
            else { // i == 25
                if (notes[j][i]) {
                    gSharp3on = 1;
                }
            }
        }
    }
    digitalWrite(latchPin1, 0);
    shiftOut(dataPin1, clockPin1, dataGREEN);
    shiftOut(dataPin1, clockPin1, dataRED);
    digitalWrite(latchPin1, 1);
    digitalWrite(latchPin2, 0);
    shiftOut(dataPin2, clockPin2, dataYELLOW);
    digitalWrite(latchPin2, 1);
    digitalWrite(g3, g3on);
    digitalWrite(gSharp3, gSharp3on);
}

void shiftOut(int myDataPin, int myClockPin, byte myDataOut) {
    int i = 0;
    int pinState;
    pinMode(myClockPin, OUTPUT);
    pinMode(myDataPin, OUTPUT);

    digitalWrite(myDataPin, 0);
    digitalWrite(myClockPin, 0);
    for (i = 7; i >= 0; i--)  {
        digitalWrite(myClockPin, 0);
        if ( myDataOut & (1<<i) ) {
            pinState= 1;
        }
        else {	
            pinState= 0;
        }
        digitalWrite(myDataPin, pinState);
        digitalWrite(myClockPin, 1);
        digitalWrite(myDataPin, 0);
    }
    digitalWrite(myClockPin, 0);
}