[LAD] a little help with mutichannel alsa

Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]
From: <grekimj@...>
To: <linux-audio-dev@...>
Date: Sunday, October 7, 2012 - 8:03 pm

--=_d82de4d0496332092d62ca5f7257299f
Content-Transfer-Encoding: quoted-printable
Content-Type: text/plain; charset="utf-8"

BODY { font-family:Arial, Helvetica, sans-serif;font-size:12px;
First, what I would like to do is pick which channel I send audio to
on the RME 9632 card.=20
My RME card is device 0. =20
When I call this function:=20
snd_pcm_open(&handle,device,SND_PCM_STREAM_PLAYBACK,0)
And set device =3D plughw:0,0 I get playback across all the RME
outputs.
(Just using hw:0,0 without the "plug" prefix does not work for some
reason which may or may not matter.)
So, how do I access the subdevices/channels? =20
When I run aplay -l I only see 1/1 subdevices.
Shouldn't I be able to set my device to hw:0,0,1 or plughw:0,0,1 to
access channel 2, for example?
There's no .asoundrc. Do I need it for this?
Finally, when attempting multichannel alsa, I assume I need to
simply make an array of pointers to the same datatype as "handle" and
run through
initializing each handle separately. =20
In the first time thought the loop, I can get handle[0] and all its
parameters to initialize without errors. =20
When I try to initialize handle[1] on a new device such as
plughw:0,0,1 I get an error that the device or resource is busy.=20
I feel like I've hit a brick wall here. Perhaps I am out of my
league. But, it feels tantilizingly close to working.
Thanks guys/gals!!=20
Grekim
=20
--=_d82de4d0496332092d62ca5f7257299f
Content-Transfer-Encoding: quoted-printable
Content-Type: text/html; charset="utf-8"

BODY { font-family:Arial, Helvetica, sans-serif;font-size:12px; First, what I would like to do is pick which channel I send audio to o=
n the RME 9632 card.
My RME card is device 0. 
When I call this function:  snd_pcm_open(&handle,device,SND_PCM_ST=
REAM_PLAYBACK,0)

And set device =3D plughw:0,0   I get playback across all the RME=
outputs.
(Just using hw:0,0  without the "plug" prefix does not work for some r=
eason which may or may not matter.)

So, how do I access the subdevices/channels? 
When I run aplay -l I only see 1/1 subdevices.
Shouldn't I be able to set my device to hw:0,0,1 or plughw:0,0,1 to access =
channel 2, for example?
There's no .asoundrc.  Do I need it for this?

Finally, when attempting multichannel alsa, I assume I need to simply make =
an array of pointers to the same datatype as "handle" and run through
initializing each handle separately. 
In the first time thought the loop, I can get handle[0] and all its paramet=
ers to initialize without errors. 
When I try to initialize handle[1] on a new device such as plughw:0,0,1 I g=
et an error that the device or resource is busy.
I feel like I've hit  a brick wall here.  Perhaps I am out of my =
league.  But, it feels tantilizingly close to working.
Thanks guys/gals!!
Grekim

--=_d82de4d0496332092d62ca5f7257299f--

Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]

Messages in current thread:
[LAD] a little help with mutichannel alsa, , (Sun Oct 7, 8:03 pm)
Re: [LAD] a little help with mutichannel alsa, Paul Davis, (Sun Oct 7, 10:40 pm)
Re: [LAD] a little help with mutichannel alsa, Fons Adriaensen, (Mon Oct 8, 8:52 am)