Example Code for Arduino-MIDI Send Receive Test

Sample Code

// SparkFun MIDI Sheild and MIDI Breakout test code
// Defines bare-bones routines for sending and receiving MIDI data
// Written 02/16/10


// defines for MIDI Shield components only
#define KNOB1  0
#define KNOB2  1

#define BUTTON1  2
#define BUTTON2  3
#define BUTTON3  4

#define STAT1  7
#define STAT2  6

#define OFF 1
#define ON 2
#define WAIT 3

byte incomingByte;
byte note;
byte velocity;
int pot;

byte byte1;
byte byte2;
byte byte3;

int action=2; //1 =note off ; 2=note on ; 3= wait



void setup() {

  pinMode(STAT1,OUTPUT);
  pinMode(STAT2,OUTPUT);

  pinMode(BUTTON1,INPUT);
  pinMode(BUTTON2,INPUT);
  pinMode(BUTTON3,INPUT);

  digitalWrite(BUTTON1,HIGH);
  digitalWrite(BUTTON2,HIGH);
  digitalWrite(BUTTON3,HIGH);

  for(int i = 0;i < 10;i++) // flash MIDI Sheild LED's on startup
  {
    digitalWrite(STAT1,HIGH);
    digitalWrite(STAT2,LOW);
    delay(30);
    digitalWrite(STAT1,LOW);
    digitalWrite(STAT2,HIGH);
    delay(30);
  }
  digitalWrite(STAT1,HIGH);
  digitalWrite(STAT2,HIGH);

  //start serial with midi baudrate 31250
  Serial.begin(31250);
}

void loop () {

  //*************** MIDI OUT ***************//

  pot = analogRead(0);
  note = pot/8;  // convert value to value 0-127
  if(button(BUTTON1) || button(BUTTON2) || button(BUTTON3))
  {
    Midi_Send(0x90,note,0x45);
    while(button(BUTTON1) || button(BUTTON2) || button(BUTTON3));
  }

  //*************** MIDI LOOPBACK ******************//
  if(Serial.available() > 0)
  {
    byte1 = Serial.read();
    byte2 = Serial.read();
    byte3 = Serial.read();

    Midi_Send(byte1, byte2, byte3);
  }

  //*************** MIDI IN ***************//
  if (Serial.available() > 0) {
    // read the incoming byte:
    incomingByte = Serial.read();

    // wait for as status-byte, channel 1, note on or off
    if (incomingByte== 144) // Note on
    {
      action = OFF;
    }
    else if (incomingByte== 128) // Note off
    {
      action = ON;
    }
    else if (note==0 && action != WAIT) // note on, wait for note value
    {
      note=incomingByte;
    }
    else if (note!=0 && action != WAIT)  // velocity
    {
      velocity=incomingByte;
      if(action == ON){
        Midi_Send(0x90,note,velocity);
      }
      if(action == OFF){
        Midi_Send(0x80,note,velocity);
      }
      note=0;
      velocity=0;
      action=WAIT;
    }
    else{
    }
  }

}

void Midi_Send(byte cmd, byte data1, byte data2) {
  Serial.print(cmd, BYTE);
  Serial.print(data1, BYTE);
  Serial.print(data2, BYTE);
}

void blink(){
  digitalWrite(STAT1, HIGH);
  delay(100);
  digitalWrite(STAT1, LOW);
  delay(100);
}

char button(char button_num)
{
  return (!(digitalRead(button_num)));
}