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4) If you are still having problems try disconnecting items from the board (such as
keyboard, mouse, monitor, hard drives, CD-ROM drives, floppy drives, or serial
peripheral devices) sometimes they can prevent the board from booting.
Q. How do I get my single board computer to play or record sound?
A. On the base SiB, no audio devices exist. In order to create them, you must press "W"
on startup when prompted, so that the root filesystem is mounted read/write. Then, go to
a command prompt as root and issue the following commands, one per line:
mknod /dev/mixer c 14 0
mknod /dev/sequencer c 14 1
mknod /dev/midi c 14 2
mknod /dev/dsp c 14 3
mknod /dev/audio c 14 4
mknod /dev/sndstat c 14 6
sync
shutdown -r now
The SiB should reboot, and you should then see the sound device files in
/dev (/dev/mixer, /dev/sequencer, etc).
Q. Would adding just these basic modules and nothing else make the SiB work with
ALSA?
A. No, in addition, you must compile the ALSA sound kernel modules against a 2.2.14
kernel (present on the SiB). Compile **just** the kernel modules, and move them to the
appropriate place on the SiB, which is /lib/modules/2.2.14/??. In addition, from my
ALSA needs some additional devices, which you will need to create via the mknod
command.
Q. I have a single board computer which I am using for a VoIP application. However my
problem is that the application is written to be compatible with the ALSA package and I
cannot compile the ALSA package on the SBC because of storage limitations and lack of
a development environment. I need to know if I can export only the required modules and
binaries from the already compiled package on a PC and make it work
A. Off course you can. The alsa-drivers are just kernel-modules. So the way to go is:
compile the right kernel; compile the Alsa-modules; copy kernel and specific modules to
the board and test.
Please be aware of the fact that you need not only the specific sound card module, but
also a couple of generic modules. You might want to dry-run it on a regular PC, just to
see what gets loaded when you load an Alsa sound card module.
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