Phytec phyBoard Wega AM335x, Application Manual

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Accessing the phyBOARD-Wega Interfaces
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PHYTEC Messtechnik GmbH 2014 L-792e_1
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3.2.5.1 Software Implementation
Audio support on the module is done via the I
2
S interface and controlled via I
2
C.
On the phyBOARD-Wega the audio codec's registers can be accessed via the I2C0 interface
at address 0x18 (7-bit MSB addressing).
To check if your soundcard driver is loaded correctly and what the device is called, type:
aplay ‐ L
A wav file can be copied to the board using scp and then played through the sound
interface.
aplay ‐ vv file.wav
Not all wave formats are support by the sound interface. Use Audacity on your host to
convert any file into 44100:S16_LE wave format which should be supported on all
platforms.
To identify channel numbers run speaker-test :
speaker ‐ test ‐ c 2 ‐ t wav
An external audio source can be connected to the input, in order to record a sound file
which then can be played back.
arecord ‐ c 2 ‐ r 441000 ‐ f S16_LE test.wav;
aplay test.wav
Inspect your soundcards capabilities with:
alsamixer
You should see a lot of options as the audio-ICs have a lot of features you can play with. It
might be better to open
alsamixer via ssh instead of the serial console, as the console
graphical effects could be better. You have either mono or stereo gain controls for all the
mix points. "MM" means the feature is muted, which can be toggled by hitting m .