Little changes...

This commit is contained in:
Jaroslav Kysela 1998-12-10 09:12:59 +00:00
parent 883bce0b96
commit 511d11e583

View file

@ -8,7 +8,9 @@ alsactl \- advanced controls for ALSA soundcard driver
.SH DESCRIPTION
\fBalsactl\fP is used to control advanced settings for the ALSA
soundcard drivers. It supports multiple soundcards.
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
@ -53,15 +55,15 @@ 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 outputs, joystick/game ports, some MIDI
routing options, etc.).
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 will tell you which flags you
can set for each channel. The comments start with semicolons. To set a
flag, simply add it to the channel() line you want.
"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
@ -81,7 +83,7 @@ The channel is stereo.
.TP
\fIrecord\fP
Use the channel as a recording source.
The channel may be used as a recording source.
.TP
\fIjoin-record\fP
@ -90,23 +92,23 @@ and right at once; they cannot be toggled independently.
.TP
\fIrecord-by-mute\fP
Allow recording the channel even if it's muted, so you can avoid
feeding your record source to the speakers. Not all hardware supports this.
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
This flag is purely informational: it tells you that the channel
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), which don't have this flag set.
source channels (like OPL-3 synth).
.TP
\fIdigital\fP
If you have a card with digital outputs and/or inputs, this flag
toggles digital output/input for the channel.
This channel is fed to an onboard digital mixer for possible hardware
processing (for instance, surround-sound processing if your card has it).
.PP
Another feature of the configuration file is the \fIboolean\fP switches
The configuration file also has \fIboolean switches\fP
which are used to toggle certain card-specific advanced features. For
example:
@ -114,8 +116,8 @@ example:
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" and
run \fBalsactl restore\fP.
currently turned off. To turn it on, just change "false" to "true,"
save the config file, and run \fBalsactl restore\fP.
.SH EXAMPLES
@ -124,11 +126,12 @@ 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, volume will be set to 40 for the left
and 50 for the right, but both will be muted (by hardware).
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
@ -143,3 +146,6 @@ None known.
.SH AUTHOR
\fBalsactl\fP is by Jaroslav Kysela <perex@jcu.cz>
This document is by Paul Winkler <zarmzarm@erols.com>.