mirror of
https://github.com/alsa-project/alsa-utils
synced 2024-11-09 23:45:43 +01:00
151 lines
4.1 KiB
Groff
151 lines
4.1 KiB
Groff
.TH ALSACTL 1 "25 Nov 1998"
|
|
.SH NAME
|
|
alsactl \- advanced controls for ALSA soundcard driver
|
|
|
|
.SH SYNOPSIS
|
|
|
|
\fBalsactl\fP [\fIoptions\fP] [\fIstore\fP|\fIrestore\fP] <card #>
|
|
|
|
.SH DESCRIPTION
|
|
\fBalsactl\fP is used to control advanced settings for the ALSA
|
|
soundcard drivers. It supports multiple soundcards. If your card has
|
|
features that you can't seem to control from a mixer application,
|
|
you have come to the right place.
|
|
|
|
.SH INVOKING
|
|
|
|
\fBalsactl\fP [\fIoptions\fP] [\fIstore\fP|\fIrestore\fP] <card #>
|
|
|
|
.SS Commands
|
|
|
|
\fIstore\fP saves the current driver setup for the selected soundcard
|
|
to the configuration file.
|
|
|
|
\fIrestore\fP loads driver setup for the selected soundcard from the configuration file.
|
|
|
|
If no soundcards are specified, setup for all cards will be saved or
|
|
loaded.
|
|
|
|
.SS Options
|
|
|
|
.TP
|
|
\fI-h, --help\fP
|
|
Help: show available flags and commands.
|
|
|
|
.TP
|
|
\fI-f, --f\fP file
|
|
Select the configuration file to use. The default is /etc/asound.conf
|
|
|
|
.TP
|
|
\fI-d, --debug\fP
|
|
Use debug mode: a bit more verbose.
|
|
|
|
.TP
|
|
\fI-v, --version\fP
|
|
Print alsactl version number.
|
|
|
|
.SH FILES
|
|
\fI/etc/asound.conf\fP (or whatever file you specify with the
|
|
\fB-f\fP flag) is used to store current settings for your
|
|
soundcards. The settings include all the usual soundcard mixer
|
|
settings. More importantly, alsactl is
|
|
capable of controlling other card-specific features that mixer apps
|
|
usually don't know about.
|
|
|
|
The configuration file is generated automatically by running
|
|
\fBalsactl store\fP. Editing the configuration file by hand may be
|
|
necessary for some soundcard features (e.g. enabling/disabling
|
|
automatic mic gain, digital output, joystick/game ports, some future MIDI
|
|
routing options, etc).
|
|
|
|
.SS Configuration File Syntax
|
|
|
|
There are some terms in the config file that bear explaining. The
|
|
"capabilities" comments before each line tells you some
|
|
characteristics of each channel. This is purely informational; these
|
|
are not flags you can set. Capabilities are listed below.
|
|
|
|
.TP
|
|
\fIhardware-mute\fP
|
|
The soundcard itself is capable of muting the channel.
|
|
Otherwise, kernel midlevel code will set the volume to minimum when an
|
|
application requests muting on this channel.
|
|
|
|
.TP
|
|
\fIjoin-mute\fP
|
|
Muting this channel can \fBonly\fP be
|
|
toggled for left and right at the same time, \fBnot\fP independently
|
|
-- even if you can control the volumes for left and right independently!
|
|
|
|
.TP
|
|
\fIstereo\fP
|
|
The channel is stereo.
|
|
|
|
.TP
|
|
\fIrecord\fP
|
|
The channel may be used as a recording source.
|
|
|
|
.TP
|
|
\fIjoin-record\fP
|
|
Recording from this channel can only be toggled for \fBboth\fP left
|
|
and right at once; they cannot be toggled independently.
|
|
|
|
.TP
|
|
\fIrecord-by-mute\fP
|
|
This channel can be recorded even if it's muted, so you can avoid
|
|
feeding your record source back to the speakers.
|
|
|
|
.TP
|
|
\fIexternal-input\fP
|
|
The channel
|
|
controls a signal from an external input (like Line-In or CD). This
|
|
serves to distinguish external source channels from onboard
|
|
source channels (like OPL-3 synth).
|
|
|
|
.TP
|
|
\fIdigital\fP
|
|
This channel is fed to an onboard digital mixer for possible hardware
|
|
processing (for instance, surround-sound processing if your card has it).
|
|
|
|
.PP
|
|
The configuration file also has \fIboolean switches\fP
|
|
which are used to toggle certain card-specific advanced features. For
|
|
example:
|
|
|
|
; Type is 'bool'.
|
|
switch( "MIC Gain", false )
|
|
|
|
This shows that my card has a switchable mic gain, and that it's
|
|
currently turned off. To turn it on, just change "false" to "true,"
|
|
save the config file, and run \fBalsactl restore\fP.
|
|
|
|
|
|
.SH EXAMPLES
|
|
|
|
Let's say I have this entry in /etc/asound.conf for my PCM output.
|
|
|
|
; Capabilities: stereo hardware-mute digital.
|
|
; Accepted channel range is from 0 to 63.
|
|
channel( "PCM", stereo( 40 mute, 50 mute ))
|
|
|
|
When \fBalsactl restore\fP is run, the PCM volume will be set
|
|
to 40 for the left and 50 for the right, but both will be
|
|
muted. Since this card supports \fIhardware-mute\fP, muting will be done by
|
|
hardware rather than by zeroing the levels.
|
|
|
|
.SH SEE ALSO
|
|
\fB
|
|
amixer(1),
|
|
alsamixer(1),
|
|
aplay(1)
|
|
\fP
|
|
|
|
.SH BUGS
|
|
None known.
|
|
|
|
.SH AUTHOR
|
|
\fBalsactl\fP is by Jaroslav Kysela <perex@suse.cz>
|
|
This document is by Paul Winkler <zarmzarm@erols.com>.
|
|
|
|
|
|
|