Issues sending midi messages over DIN while also using bluetooth on esp32 c3 dev board

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1

I've been working on a project for a little while now attempting to create an interface box that can receive bluetooth MIDI commands and forward them along a DIN midi cable. I'm having issues with the DIN midi portion of the project specifically. When I attempt to send midi commands over serial it fails, and I get garbage messages when the dev board is starting up. I have succeeded in sending midi messages as raw serial when I initialize the port directly, but have not succeeded in getting midi library to work. I've tried a bunch of different approaches. I have two XIAO ESP32 c3 dev boards, one is for a simple controller attached to a 5-way switch. So far what works:

I can initialize BLE midi and connect the client and server and send BLE midi messages
I can send raw midi over serial

Things I've tried that don't work:
Sending messages using MIDI.h
Sending messages using Control_Surface.h
Sending messages using the default serial0
Sending messages using serial1 at all
Here is the code that works:

#include <MIDI.h>
#include <BLEMidi.h>
#include <HardwareSerial.h>
#include <Control_Surface.h>

void onNoteOn(uint8_t channel, uint8_t note, uint8_t velocity, uint16_t timestamp)
{
    // Code to test midi messages directly over serial
    int noteON = 144;//144 = 10010000 in binary, note on command
    int noteOFF = 128;//128 = 10000000 in binary, note off command
    MIDImessage(noteON, 51, velocity);//turn note on

    Serial.printf("Note on : channel %d, note %d, velocity %d (timestamp %dms)\n", channel, note, velocity, timestamp);

}
void setup() {
    Serial.begin(115200);
    Serial.println("Initializing Bluetooth...");
    BLEMidiClient.begin("MIDI Client");

   // Configure MySerial0 on pins TX=D6 and RX=D7 (-1, -1 means use the default)
    
    MySerial0.begin(31250, SERIAL_8N1, -1, -1);
    MySerial0.print("MySerial0");

    Serial.println("Waiting for connections...");
    
    // Register the Control Change callback
    BLEMidiClient.setControlChangeCallback(handleControlChange);
    BLEMidiClient.setOnDisconnectCallback([](){     // To show how to make a callback with a lambda function
        Serial.println("Disconnected");
        digitalWrite(led_pin, LOW);
    });
    BLEMidiClient.setOnConnectCallback([](){ 
        Serial.println("Connected");
        digitalWrite(led_pin, HIGH); 
    });
    BLEMidiClient.setNoteOnCallback(onNoteOn);
    
}

void loop() {
   
    if(!BLEMidiClient.isConnected()) {
        // If we are not already connected, we try te connect to the first BLE Midi device we find
        int nDevices = BLEMidiClient.scan();
        if(nDevices > 0) {
            if(BLEMidiClient.connect(0))
                Serial.println("Connection established");
            else {
                Serial.println("Connection failed");
                delay(3000);    // We wait 3s before attempting a new connection
            }
        }
    }
}

//send MIDI message
void MIDImessage(int command, int MIDInote, int MIDIvelocity) {
  MySerial0.write(command);//send note on or note off command 
  MySerial0.write(MIDInote);//send pitch data
  MySerial0.write(MIDIvelocity);//send velocity data
}

I'm pretty new to Arduino, but have beed coding for many years. I suppose I could roll my own midi library to send raw messages over serial, but seems like a lot of wheel re-invention. Anyone have thoughts?

2

Show the serial output, telling us it failed does not help.