On Wednesday 01 April 2009 at 19:46:30 Clemens Ladisch wrote: > Justin Smith wrote: > > On Wed, Apr 1, 2009 at 3:32 AM, Clemens Ladisch <cladisch@xxxxxxxxxxxx> wrote: > > > Please note that neither the USB MIDI protocol nor ALSA's sequencer > > > messages can use running status. > > > > If I understand correctly, running status is not an alternative to the > > MIDI protocol, > > It is a part of the MIDI protocol. > > > it is an alternative way of interpreting the bytes (comparable to > > nrpn or such), so there should be no issue of MIDI or ALSA > > incompatibility. > > Running status is a feature of the encoding used by MIDI. > > USB MIDI and the ALSA sequencer use different encodings. > > A USB MIDI adapter converts from MIDI to the USB MIDI protocol, and the > USB MIDI driver converts that data back to MIDI. It is not possible to > detect from the result whether the original MIDI data used running > status. Sorry, I do not get it. I have checked the ports using aseqdump connecting to the two UM2 ports of the external USB MIDI interface. aseqdump did not report any error message, so I think I can assume that at this connection there is no problem running status vs. normal status. I connected the two UM2 ports to the MIDI Thru port and checked to see if merging works, got no error messages from aseqdump either. I checked this both UM2 connectors at a time, then both merged into one output. I am also not sure if I got the USB MIDI part correctly: what I have is an external USB device that offers two IN/OUT ports having standard 5 pin DIN connectors each to connect to other standard MIDI devices. So this device is not transferring USB MIDI data - it is imho simply converting ordinary MIDI data into USB data without further manipulation, then inside the notebook ALSA applications see the UM2 connectors as a standard MIDI hardware port each. So the hardware ports that I see denoted as UM2 have got to be ALSA sequencer ports. I have never had any issues related to running status vs. normal status before until I wanted to use keykit to work on incoming MIDI data. This is where I cannot find what causes the error. I suspect it is keykit that needs more than one IN port and it is keykit which cannot merge two different MIDI streams that come in at its IN port - but I am not yet 101% sure about that. So in contrast to what is normally possible (connect more than one OUT port to one IN port) keykit cannot do this. Kind regards, Crypto. _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/mailman/listinfo/linux-audio-user
