Hi all,
I've written an application on the PC that works with alsa, it uses 8 mono 22050Hz 16 bit audio channels via alsa.
I'm trying to port the application to an Arm board with only a CM109 via USB.
I have a working alsa library, I can play raw audio via the aplay utility and record via arecord ok.
My problem is I don't understand the alsa configuration in enough detail to get it right. At the moment I have an alsa.conf cribbed from google, seems to work but only as a passthough.
# cat /usr/share/alsa/alsa.conf_old pcm.!default { type hw card 0 } ctl.!default { type hw card 0 }
ARM / # lsmod snd_usb_audio 65715 0 - Live 0xbf082000 snd_hwdep 4756 1 snd_usb_audio, Live 0xbf07b000 snd_pcm 54351 1 snd_usb_audio, Live 0xbf062000 snd_timer 14870 1 snd_pcm, Live 0xbf058000 snd_page_alloc 3336 1 snd_pcm, Live 0xbf052000 snd_usbmidi_lib 14853 1 snd_usb_audio, Live 0xbf048000 snd_rawmidi 14657 1 snd_usbmidi_lib, Live 0xbf03d000 snd_seq_device 4675 1 snd_rawmidi, Live 0xbf036000 cm109 6943 0 - Live 0xbf011000 dm9601 5583 0 - Live 0xbf00a000 usbnet 11888 1 dm9601, Live 0xbf000000 ARM / # cat /proc/asound/cards 0 [default ]: USB-Audio - Generic USB Audio Device Generic USB Audio Device at usb-ep93xx-3, full speed ARM / # cat /proc/asound/devices 0: [ 0] : control 16: [ 0- 0]: digital audio playback 24: [ 0- 0]: digital audio capture 33: : timer ARM / #
I do not have enough of a machine or distribution to use the alsaconf utility. Could someone help me with an alsa.conf that will do what roughly what I am after :
IE to allow an application to open N channels each 22050Hz 16 bit mono to be mixed and resampled for an output via a CM109 that only provides 44.1 or 48Khz 16 bit interleaved ... phew ...
Thanks, Jon