Midi filtertering of stop start messages

Projects Programming
9

The midi-thru connection does exactly what it is supposed to, It passes all thru. (it is actually just hardware)

Just draw us how you've connected the devices and cables please. I think we can trust that the midi shield connects properly to the arduino.

Your code should work, though if you want to keep passing midi-sync (most clocks will stop sending that after sending stop though, but this is a different matter)
then your case for clock should look like this

      case midi::Clock:
        MIDI.sendRealTime(midi::Clock);
        break;

Is it still receiving midi clock messages ?
Best practice is to use the onboard LED on the Arduino to show midi-clock messages coming in. For that you need to count them as they come in,
so

void setup() {
  MIDI.begin(MIDI_CHANNEL_OMNI);  // all channels
  MIDI.turnThruOff();             // MIDI Thru Off
 pinMode(13, OUTPUT);
}

void loop() {
  static uint8_t clk = 0;
  if (MIDI.read())                //receive msg
  {
    switch (MIDI.getType()) {     //recognize MIDI Type as MIDI Clock and MIDI Clock start, stop, continue msg's
      case midi::Clock:
        MIDI.sendRealTime(midi::Clock);
        clk++;
        clk = clk % 24;                                 // 24 clock messages per beat
        if (clk / 6) digitalWrite(13, LOW);  // this should light it up for 25% of the time
        else digitalWrite(13, HIGH);
        break;
      case midi::Start:
        break;
      case midi::Continue:
        break;
      case midi::Stop:
        break;
      default:                    //sends other types of msg's
        MIDI.send(
          MIDI.getType(),
          MIDI.getData1(),
          MIDI.getData2(),
          MIDI.getChannel()
          );
        break;
    }
  }
}