   screen.tag = 'S';
   gshock.tag = 'G';
   sound.tag = 'A';  // for Audio
+  midi.tag = 'M';
 
   led_state = false;
   interrupts();

#define CMD_AUDIO               'A'
#define CMD_BEEP                'B'

#define CMD_NOTE                'N'



    }
  }

  // Probe MIDI
  if(midi.probe) {
    if(usbMIDI.read()) {
      midi.t = time_us;
      midi.count++;
      midi.probe = false;
      led_state = !led_state;
    }
  }

  // Probe screen
  if (screen.probe) {
    int v = analogRead(PD_SCREEN_PIN);
