Re: [LAD] "Open midi-keyboard"

> Jens M Andreasen wrote:
>> On Sat, 2009-09-26 at 14:03 +0200, Ralf Mardorf wrote:
>>
>>
>>> When using several MIDI ports even a lot of SysEx can be sent
>>> real-time, but using only one MIDI port even aftertouch can cause
>>> timing problems.
>>
>> A stream of channel-aftertouch is single bytes, and can at any point be
>> interrupted by more important data (note-on) with at most 0.3
>> miliseconds delay ...
>
> When interrupted it's 2 bytes, one byte only when running status can
> take effect. To be honest, I don't know if aftertouch will be
> interrupted by applications and devices by default. Is this MIDI
> standard? And to be honest, much more data is produced by the pitch
> wheel, because of the low and high byte. I never had any timing issues
> because of aftertouch and pitch bend, but I noticed that they produce
> much more traffic than real-time SysEx for filters. IIRC I had 4 MIDI
> outputs for the Atari ST, I guess using just one MIDI output can cause
> trouble for pure MIDI music.
>
> Ralf

Yes, the Midex had 4 MIDI outs.

Have you tested heavy traffic with just one MIDI port?

I can't speak for aftertouch, but SysEx can become problematic. Okay,
SysEx always needs to be transmitted from $F0 to $F7, while aftertouch
can be interrupted, anyway, aftertouch can cause really a lot of data,
much more than SysEx for filters.
_______________________________________________
Linux-audio-dev mailing list
Linux-audio-dev@email-addr-hidden
http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
Received on Sun Sep 27 00:15:09 2009