Raspberry PI 聲音控制
指令
- amixer
amixer controls
amixer cget numid=3
amixer cset numid=3 50%
amixer cset numid=3 50%,100% // 左聲道 50% 右聲道 100%
amixer cset numid=4 off // 靜音
vi /etc/init.d/alsa-utils 主要用來控制 ALSA script
vi /var/lib/alsa/asound.state // ALSA 資料儲存地方執行完下列動作後：
$ amixer cset numid=3 100%
numid=3,iface=MIXER,name='Master Playback Volume'
; type=INTEGER,access=rw------,values=2,min=0,max=65536,step=1
: values=65536,65536
$ amixer cset numid=4 on
numid=4,iface=MIXER,name='Master Playback Switch'
; type=BOOLEAN,access=rw------,values=1
: values=on
$ sudo alsactl store/var/lib/alsa/asound.state 會被儲存為：
state.ALSA {
control.1 {
iface MIXER
name 'PCM Playback Volume'
value 399
comment {
access 'read write'
type INTEGER
count 1
range '-10239 - 400'
dbmin -9999999
dbmax 400
dbvalue.0 399
}
}
control.2 {
iface MIXER
name 'PCM Playback Switch'
value true
comment {
access 'read write'
type BOOLEAN
count 1
}
}
control.3 {
iface MIXER
name 'PCM Playback Route'
value 2
comment {
access 'read write'
type INTEGER
count 1
range '0 - 2'
}
}
}
- alsamixer 圖形化控制聲音工具
- alsactl
- aplay
aplay /usr/share/scratch/Media/Sounds/Vocals/Singer2.wav
aplay /usr/share/scratch/Media/Sounds/Vocals/Singer2.wav -v -V mono
aplay -l- speaker-test
重新載入工具程式
sudo /etc/init.d/alsa-utils reset
