Code of Receiving MIDI Data from USB Host Shield

Projects Programming
1

Using : Arduino UNO with USB Host Shield, A MIDI device sends MIDI through USB.

Here is the function I'm using to receive MIDI from USB and sends it to serial : (USB Host Shield 2.0 Library)

void MIDI_poll()
{
  uint8_t outBuf[ 3 ];
  uint8_t size;

  do {
    if ( (size = Midi.RecvData(outBuf)) > 0 ) { 
      //MIDI Output
      Serial.write(outBuf, size);
    }
  } while (size > 0);
}

"uint8_t RecvData(uint8_t *outBuf)"
Receive MIDI message (3 bytes)
return value is MIDI message length(0-3)

And I used MIDI Library, so my void loop looks like this:

void loop()
{
  Usb.Task();
  if ( Usb.getUsbTaskState() == USB_STATE_RUNNING )
  {
    MIDI_poll();
  }
  MIDI.read();
}

But I can't get MIDI data read from the serial.

What should I do? Is it code problem or my MIDI device not working correctly?