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From: Tim Blechmann <tim@klingt.org>
To: alsa-devel@alsa-project.org
Subject: pointer callback question
Date: Thu, 12 Feb 2009 18:50:45 +0100	[thread overview]
Message-ID: <49946175.5070008@klingt.org> (raw)


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hi all,

one question about the pointer callback.

the docs say:
>  This callback is called when the PCM middle layer inquires the current
>  hardware position on the buffer. The position must be returned in
frames,
>  ranging from 0 to buffer_size - 1.

i am using a ringbuffer to communicate with my audio device. but when
the position is reset to 0, alsa requests to stop the stream
(SNDRV_PCM_TRIGGER_STOP).

the brief log is (4 periods of 64 frames):
stream_pointer at 64
stream_pointer at 128
stream_pointer at 192
stream_pointer at 256
stream_pointer at 0

after returning 0, a stop is requested.

am i missing something?
thanks, tim

-- 
tim@klingt.org
http://tim.klingt.org

Contrary to general belief, an artist is never ahead of his time but
most people are far behind theirs.
  Edgar Varèse


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             reply	other threads:[~2009-02-12 17:50 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-02-12 17:50 Tim Blechmann [this message]
2009-02-12 17:54 ` pointer callback question Takashi Iwai
2009-02-12 17:55   ` Tim Blechmann
2009-02-12 17:58     ` Takashi Iwai
2009-02-12 18:04       ` Tim Blechmann
2009-02-13  6:26         ` Takashi Iwai
2009-02-26 14:44       ` Tim Blechmann
2009-02-28 12:48         ` Tim Blechmann

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