[LAD] "Open midi-keyboard"

Ralf Mardorf ralf.mardorf at alice-dsl.net
Sat Sep 26 21:03:40 UTC 2009


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



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