Query about Playback device name

Query about Playback device name

[Irfan Shaikh]

Hello,

         aplay uses following device
"aplay -Dplug:mcasp3 411.2Kbps-44.1Khz-16bits-2CH-PCM.wav"
 Playing WAVE '411.2Kbps-44.1Khz-16bits-2CH-PCM.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo

         I want to use same device i.e "plug:mcasp3" in my plaback application

1) Earlier i use to use default device
   //alsaParams->playback_device = strdup("plughw:0,0");

2)  Can i use following section of code to use    "plug:mcasp3"  as playback device? Will following section of code work ??????

    alsaParams->playback_device = strdup("plug:mcasp3");                 <<<<<------------------------<<<<<<<-----------------<<<<<<<

    snd_pcm_hw_params_alloca(&alsaParams->hwparams_playback);

    /*Open PCM Playback device*/
    if (snd_pcm_open(&alsaParams->playback_handle,
                     alsaParams->playback_device,
                     alsaParams->stream,
                     alsaParams->device_mode) < 0)

Thanks and regards


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Re: Query about Playback device name

[Clemens Ladisch]

Irfan Shaikh wrote:
> aplay uses following device
> "aplay -Dplug:mcasp3 411.2Kbps-44.1Khz-16bits-2CH-PCM.wav"
> 
> I want to use same device i.e "plug:mcasp3" in my plaback application
> 
> Can i use following section of code to use "plug:mcasp3" as playback device?
> 
>     alsaParams->playback_device = strdup("plug:mcasp3");
>     if (snd_pcm_open(&alsaParams->playback_handle,
>                      alsaParams->playback_device,

Yes.

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Regards,
Clemens

Re: Query about Playback device name

[Irfan Shaikh]

Hello Clemens,


#################################################################################################################################

I get following error on console if i use  plug:mcasp3  instead  plughw:0,0
ALSA lib pcm.c:2211:(snd_pcm_open_noupdate) Unknown PCM mcasp3

/********************************************************/
     //alsaParams->playback_device = strdup("plughw:0,0");    /*commented*/
     alsaParams->playback_device = strdup("plug:mcasp3");
     snd_pcm_hw_params_alloca(&alsaParams->hwparams_playback);
     /*Open PCM Playback device*/
     if (snd_pcm_open(&alsaParams->playback_handle,   alsaParams->playback_device,  alsaParams->stream,    alsaParams->device_mode) < 0)
     {
        printf("Error opening PCM device %s\n", alsaParams->playback_device);
        return NULL;
     }

/********************************************************/

# aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: EVM [TI81XX EVM], device 0: McASP3 bdrsecodec-0 []
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: EVM [TI81XX EVM], device 1: McASP4 bdrsecodec-1 []
  Subdevices: 1/1
  Subdevice #0: subdevice #0

#################################################################################################################################

Regards
Irfan


________________________________________
From: Clemens Ladisch [clemens@ladisch.de]
Sent: Wednesday, March 09, 2011 5:15 PM
To: Irfan Shaikh
Cc: alsa-devel@alsa-project.org
Subject: Re: [alsa-devel] Query about Playback device name

Irfan Shaikh wrote:
> aplay uses following device
> "aplay -Dplug:mcasp3 411.2Kbps-44.1Khz-16bits-2CH-PCM.wav"
>
> I want to use same device i.e "plug:mcasp3" in my plaback application
>
> Can i use following section of code to use "plug:mcasp3" as playback device?
>
>     alsaParams->playback_device = strdup("plug:mcasp3");
>     if (snd_pcm_open(&alsaParams->playback_handle,
>                      alsaParams->playback_device,

Yes.

> SASKEN BUSINESS DISCLAIMER:

*** DISCLAIMER ***
This e-mail contains public information intended for any subscriber of
this mailing list and for anybody else who bothers to read it; it will
be copied, disclosed and distributed to the public.  If you think you
are not the intended recipient, please commit suicide immediately.
These terms apply also to any e-mails quoted in, referenced from, or
answering this e-mail, and supersede any disclaimers in those e-mails.
Additionally, disclaimers in those e-mails will incur legal processing
fees of $42 per line; you have agreed to this by reading this disclaimer.


Regards,
Clemens

Re: Query about Playback device name

[Clemens Ladisch]

Irfan Shaikh wrote:
> I get following error on console if i use  plug:mcasp3  instead  plughw:0,0
> ALSA lib pcm.c:2211:(snd_pcm_open_noupdate) Unknown PCM mcasp3

Do aplay and your program run on same computer as the same user?


Regards,
Clemens

Re: Query about Playback device name

[Irfan Shaikh]

YES....
I am running my application as well as aplay on the same embedded platform with same user

________________________________________
From: Clemens Ladisch [clemens@ladisch.de]
Sent: Wednesday, March 09, 2011 7:52 PM
To: Irfan Shaikh
Cc: alsa-devel@alsa-project.org
Subject: Re: [alsa-devel] Query about Playback device name

Irfan Shaikh wrote:
> I get following error on console if i use  plug:mcasp3  instead  plughw:0,0
> ALSA lib pcm.c:2211:(snd_pcm_open_noupdate) Unknown PCM mcasp3

Do aplay and your program run on same computer as the same user?


Regards,
Clemens

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 virus transmitted by this email.
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