Seeeduino XIAO MIDI

Support
1

I have a Seeeduino XIAO and it works well so far apart from trying to use MIDI. I am using the Adafruit_TinyUSB.h library and for basic note on / note off stuff it works fine. However, as soon as I send a CC message ( in my case CC 7 - volume ) strange things happen. Messages don’t appear to be sent until another note on message. So I will send a note off message followed by a CC message and nothing appears in the midi monitor. So the note is hanging. As soon as the next note on message comes along out pops the note off and the CC message followed by the note on message.

If you take the midi-test from the libraries’ example folder and change the step through time to one second, then replace the send section with:-
// Send Note On for current position at full velocity (127) on channel 1.
MIDI.sendNoteOn(note_sequence[position], 127, 1);
MIDI.sendControlChange(7, 100, 1) ;
delay(100);
MIDI.sendNoteOff(note_sequence[position], 0, 1);
// Increment position
position++;
You will here the notes hanging until replaced by the next one. If you comment out the sending of the CC message, it works as expected with just a short beep for each note.

Problem is it is not an Adafruit product so I don’t think they would be interested. So has anyone any suggestions?

2

So I’m not an expert on the midi thing but I did manage to get a Xiao working as a USB HID device with circuit python. It’s a bit of a faff to get Circuit Python onto the Xiao and it doesn’t have a lot of space for libraries but it might help you try an alternative approach instead of using it in Arduino?

3

btw forgot to mention, if the Xiao doesn’t work out the Adafruit QTPy will be out in the near future. It has the same form factor but the ability to increase the memory by adding an SPI flash chip to the bottom which solves the space for libraries issue. The day this thing comes out I’m ordering like five because it’s such an awesome little board!

4

Thanks for that, I saw it would work with Python but I am after something much faster than Python can delver.
I was after a quick demo for this evening but after two days of struggling with this I came to the conclusion that the library was bust. I have done tons of MIDI projects and even written a book about the subject so I should know what I am doing, but you never know.
Thanks anyway.
Mike