[jack_umidi] baud rate when writing MIDI messages from USB to jack_umidi

[Hans Petter Selasky]

On 2019-05-29 16:52, Marcel Bonnet wrote:
> On Wed, 29 May 2019 at 11:27, Hans Petter Selasky <hps at selasky.org> wrote:
> 
>> On 2019-05-29 16:15, Marcel Bonnet wrote:
>>> Hello.
>>>
>>> I'm making a MIDI controller with Arduino UNO and I though somebody could
>>> help me on clarify if I should set a specific baud rate when writing MIDI
>>> messages from Arduino (from USB port) that are target to jack_umidi.
>>>
>>> I realize that whem I'm writing chars (debug messages) they are
>> interpreted
>>> as random MIDI notes. But when I turn debug off and write something like:
>>>
>>>         Serial.write(0x90);
>>>         Serial.write(0x30);
>>>         Serial.write(0x7F);
>>>         Serial.flush();
>>>
>>> no MIDI message is received (I used jack_midi_dump to check, it is
>> empty) .
>>>
>>> So I'm not asking about Arduino itself, but maybe it is something related
>>> to the baud rate?
>>>
>>
>> The USB protocol use a classification byte. Every USB MIDI command is
>> always 4-bytes long.
>>
>> Regular MIDI is using 64000 baud I think.
>>
>> --HPS
>>
>>
> Thanks a lot HPS!
> 
> BTW, I looked at
> http://www.gweep.net/~prefect/eng/reference/protocol/midispec.html : it
> states 31250 baud for MIDI.
> 
> I'm opening the arduino USB device as:
> $ jack_umidi -S -B -C /dev/cuaU0
> 
> In this case, 9600 baud is too slow? Should I set to 31250 next time?
> 
> Thanks in advance,
> 

I've never tested jack_umidi like this :-)

Maybe you'll need to patch it to set the baud rate.

--HPS