How to use the audio interface
From IGEP - ISEE Wiki
How to get sound out (audio out)
The amplifiers for the headset output are disabled by default, so the first thing you'll do is enable these amplifiers with:
amixer set -D hw:0 'Headset' 0dB amixer set -D hw:0 'HeadsetL Mixer AudioL2' on amixer set -D hw:0 'HeadsetR Mixer AudioR2' on
Then you can easily play a *.wav sound with the application Aplay, for example:
aplay sample.wav
How to get sound in (audio in)
Enable capture:
$ amixer -c 0 sset 'Analog Right AUXR' cap $ amixer -c 0 sset 'Analog Left AUXL' cap
You can record audio in with the application Arecord, for example:
arecord -t wav -c 2 -r 44100 -f S16_LE -v audio-in.wav
Following output is expected on console:
Recording WAVE 'audio-in.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo Plug PCM: Hardware PCM card 0 'TWL4030' device 0 subdevice 0 Its setup is: stream : CAPTURE access : RW_INTERLEAVED format : S16_LE subformat : STD channels : 2 rate : 44100 exact rate : 44100 (44100/1) msbits : 16 buffer_size : 32768 period_size : 2048 period_time : 46439 tick_time : 7812 tstamp_mode : NONE period_step : 1 sleep_min : 0 avail_min : 2048 xfer_align : 2048 start_threshold : 1 stop_threshold : 32768 silence_threshold: 0 silence_size : 0 boundary : 1073741824
When ever you think you want to stop recording just press CTRL+C
