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[linrad] Re: Knoppix 4.01

Hello Roger, sorry, I think I misunderstood you problem. I understand
that you need to get two cards working at the same time.

Look at this insteresting file. I do not know if you have it on the
knoppix, it is located at /usr/share/doc/alsa-base/README.Debian.gz

Note this sentence:

"alsaconf can only detect one sound card and is generally
a poorly written program."

Here you have the clues to configure two different sound cards by hand.
It is very easy if you know what modules to load. It is not the complete
file, if you need it complete I can send it to you.

Depending on what kernel Knoppix uses, the file that you must edit can
change its name.  /etc/modprobe.d/alsa-base will probably be right name.
You can edit it and add the "alias" and "options" for your modules at
the end of that file. In this document, it uses the name "sound" for
that file, but if you put the "sound" file it can be messed with the
"alsa-base" file, so a conflict must be avoided.

loading modules
You can arrange for ALSA modules to be loaded at boot time by installing
the discover or hotplug packages or by adding the names of sound card
driver modules to /etc/modules in order of increasing index.

ALSA has a special built-in module autoloading system.  You do not have
to make use of it, but in case you do, here is a brief explanation of
how it is supposed to work.

When the "snd" module is loaded and the user tries to open a sound device
file with a minor number that indicates that card number N is wanted, snd
modprobes "snd-card-N".  Thus, if you set up module loader configuration
file /etc/modutils/sound or /etc/modprobe.d/sound to look like this:

    alias snd-card-0 snd-cs46xx
    options snd-cs46xx index=0

then snd-cs46xx will be automagically loaded when it is needed to handle
the attempted open() of the sound device.  The "index=0" option ensures
that when snd-cs46xx is loaded the first card that it registers is given
index 0.

If you have an additional sound card of the same type then make the file
look like this:

    alias snd-card-0    snd-cs46xx
    alias snd-card-1    snd-cs46xx
    options snd-cs46xx  index=0,1

If you have, instead, an additional sound card of a different type then
make the file look like this:

    alias snd-card-0    snd-cs46xx
    options snd-cs46xx  index=0
    alias snd-card-1    snd-emu10k1
    options snd-emu10k1 index=1

ALSA supports up to eight sound cards.

The alsaconf program, available in the alsa-utils package (in Debian
(but not in Ubuntu), performs hardware detection and can write out a
module loader configuration file that looks like the above.
Unfortunately, alsaconf can only detect one sound card and is generally
a poorly written program.  Another way of discovering what module(s)
you need is to install the "discover" package and to run the following
command as root:

  discover --data-path=linux/module/name --data-version=$(uname -r) audio

This will print out the name of the sound card driver module(s) that
you need to use.

The module loader configuration files just described are additional to
the files /etc/modutils/alsa-base and /etc/modprobe.d/alsa-base which are
shipped as conffiles with the alsa-base package.  The latter files
contain basic configuration entries which don't normally need to be
customized.  The entries are of several kinds:

* entries for the "snd" module;
* ALSA autoloader aliases;
* entries that install OSS-emulation and other drivers above drivers
  upon which these depend;
* an entry for each normal sound card driver that will cause a script
  to be run after the driver has initialized;
* an entry for each abnormal driver (i.e., a driver that drives
  hardware such as a TV card or modem that is not suited to be the
  primary sound card) preventing it from grabbing index 0;

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