[PlanetCCRMA] MidiMan 2x2 Question

Mark Knecht markknecht@attbi.com
Fri Dec 13 15:48:01 2002


On Fri, 2002-12-13 at 15:32, Fernando Pablo Lopez-Lezcano wrote:
> >    I have been continuing to work on this HDSP 9652 MIDI stuff and ran
> > across one piece of data that confused me a bit. It is my understanding
> > that the MidiMan 2x2 is a 2 port MIDI device, and it acts like a two
> > port device inside of Rosegarden as far as I can tell. However, I'm
> > puzzled over the entries I see in /dev/snd.
> > 
> >    If I boot my PC with the 2x2 disconnected and then do an ls of
> > /dev/snd, I see what appears to be the two ports on the HDSP 9652. When
> > I plug in the MidiMan, I only see a single port added. Is this correct
> > operation?
> 
> I think it is. The two ports appears as subdevices of the device that
> gets created. Apparently it is not possible to create individual devices
> for midi ports because there are not enough free device numbers. I don't
> know why the hdsp creates two devices. This was discussed a bit on
> alsa-dev (I think) until Jaroslav pointed out the limitation on the
> number of device numbers (it is a problem with bigger interfaces, for
> example 8 port midi devices). 
> 

Fernando,
   Thanks. I'm just studying and trying to understand how all of this
works.

   There are a couple of other thing that I'm seeing with the 2X2 when I
watch it and test it:

1) Sometimes, if I boot with the 2X2 plugged in, I get a boot time
message about Alsa failing to start.

2) Right now, if I unplug and plug in the 2X2 a couple fo times, the
system no longer sees it and doesn't create the /dev/snd devices at all.

   So, hot plugging the device too many times seems like not such a good
idea right now...

Mark