Usb-usx2y

From the ALSA wiki

1 Getting Tascam soundcards to work with ALSA
2 MIDI support
3 Audio support
4 Bugs
5 Comments
6 See also

Getting Tascam soundcards to work with ALSA

The new Tascam soundcards now have ALSA drivers, thanks to the work done by Martin Langer [1]. You will need a recent kernels (>= 2.6.5 ?) have the usx2y driver. You will also need to have the and the alsa-firmware package. The most recent version of the driver are available in the alsa-driver package. You will also need the hotplug scripts and the usx2yloader utility, which are found in alsa-firmware. The hotplug scripts execute the following at "plug" time:

modprobe snd-usb-usx2y
/sbin/fxload -s ${prefix}/share/alsa/firmware/usx2yloader/tascam_loader.ihx \
        -I ${prefix}/share/alsa/firmware/usx2yloader/us122fw.ihx \
        -D /proc/bus/usb/001/002

You will still need to manually run :

usx2yloader

On debian, the cards work with current kernel-image 2.6.10 along with:

firmware (${prefix}/share/alsa/firmware/usx2yloader/)
loader (${prefix}/bin/usx2yloader)
hotplug (/etc/hotplug/usb/tascam_{fpga,fw,fw.usermap})

MIDI support

Midi support is provided by the usb-audio module.

Audio support

The usb-usx2y module is in charge of the audio. Note there is no software mixer. The following is an example for .asoundrc file:

pcm.us122 {
    type hw;
    card 3;
}                                                                                                  
pcm.usx {
    type plug;
    slave.pcm us122;
}

Bugs

Kernel version must be >=2.6.1 (otherwise audio would not work at all, and trying to remove the module would freeze the machine). MIDI seem to work ok (provided snd-seq is loaded). Right now, still a few bugs, where the sync is lost:

ALSA /usr/src/modules/alsa-driver/usb/usx2y/usbusx2yaudio.c:363: play urb->status = -63

The card does not seem to work well when plugged to an ohci usb bus.

Comments

I could not have jack working using directly the alsa drivers. Instead, jack worked in OSS mode, playback only with a 128 long buffer. Trying to have jack in alsa mode give the following error, and jackd crashes soon after:

Mar 10 11:53:58 localhost kernel: -28
Mar 10 11:53:58 localhost kernel: Sequence Error!(ep=10;nuc=1,frame=106)
Mar 10 11:53:58 localhost kernel: Sequence Error!(ep=8;nuc=0,frame=106)