Re: [LAU] MIDI keyboard not recognized

Hi,

On Tuesday 11 September 2012, jy wrote:
> still no appearance of the midi keyboard.
>
> I also tried with all proposed audio cards in qjackctl setup but still no
> midi keyboard (even though the keyboard is correctly listed as an
> interface in the interface combo box)
>
> I'm starting to feel like this is hopeless (i'm gonna shed a tear) :-)
>
> just to know, how does jack know about the midi devices present. does it
> rely on ALSA ?

Yes. Jack depends on ALSA drivers to work with hardware MIDI devices, just
like it depends on ALSA drivers to work with hardware audio devices, except
for FireWire devices where jack depends on ffado/freebob. Jack does not have
its own hardware drivers.
 
> Would a message found in dmesg like :
> [ 782.208027] usb 7-1: new full-speed USB device number 8 using uhci_hcd
> when plugging in the keyboard be of any interest in my case ?

Yes, it is a good sign. Answering your previous question:

> Does anyone know from where qjackctl gets its MIDI device list ?

The ALSA tab is filled from the ALSA Sequencer list of ports, which can be
hardware devices or software applications.

The MIDI tab list comes from one of those bridges that provide MIDI support
to jack.

If you should solve the problem at the ALSA level, I guess that you will be
able to solve the problem with jack as well at the same time.

ALSA provides a number of kernel modules. You can list them with this
command:

$ lsmod | grep ^snd

My guess is that some modules are not automatically loaded in your system.

Summing up your previous diagnostics, the ALSA hardware driver (snd-usb-
audio) recognizes your device properly:

$ cat /proc/asound/cards
1 [v2 ]: USB-Audio - USB Oxygen 8 v2
                     M-Audio USB Oxygen 8 v2 at usb-0000:00:1d.1-1, full

And the ALSA raw MIDI interface (snd-rawmidi) is working properly as well:

$ amidi -l
Dir Device Name
IO hw:1,0,0 USB Oxygen 8 v2 MIDI 1

In your previous messages it is not clear if the ALSA Sequencer interface is
working or not for you. To verify, there are several tests that you can try.

$ cat /proc/asound/seq/drivers
snd-seq-midi,loaded,2

$ cat /proc/asound/seq/clients
Client info
  cur clients : 4
  peak clients : 5
  max clients : 192

Client 0 : "System" [Kernel]
  Port 0 : "Timer" (Rwe-)
  Port 1 : "Announce" (R-e-)
Client 14 : "Midi Through" [Kernel]
  Port 0 : "Midi Through Port-0" (RWe-)

Another way is the ALSA sequencer player (from the ALSA tools collection):

$ aplaymidi -l
 Port Client name Port name
 14:0 Midi Through Midi Through Port-0
 20:0 MidiSport 2x2 MidiSport 2x2 MIDI 1
[...]

Or the ALSA Sequencer event monitor/receiver:

$ aseqdump -l

If some or all the above tests failed, my guess is that the ALSA Sequencer
modules aren't loaded. In that case, you may try this command:

$ sudo modprobe snd-seq-midi

Regards,
Pedro
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Received on Tue Sep 11 12:15:03 2012