[alsa-devel] Query regarding sampling rates etc
Hi, This is a very vague question, just thought of asking it after hours of debugging.
I am testing my alsa driver, written for omap 730/850 based board. I am testing it by using aplay.
Despite checking clocks, sampling rates etc many times and after doing many combinations thereof, I cant hear anything more than a noise which changes and becomes more like the original .wav file as I change various params like sampling rates/clocks etc. It becomes close to the actual thing, but not better.
Any idea what are the params I should be tweaking? I know this is h/w dependent.
-pharaoh
On Tue, 2007-07-10 at 19:32 +0530, Pharaoh . wrote:
Hi, This is a very vague question, just thought of asking it after hours of debugging.
I am testing my alsa driver, written for omap 730/850 based board. I am testing it by using aplay.
Despite checking clocks, sampling rates etc many times and after doing many combinations thereof, I cant hear anything more than a noise which changes and becomes more like the original .wav file as I change various params like sampling rates/clocks etc. It becomes close to the actual thing, but not better.
Any idea what are the params I should be tweaking? I know this is h/w dependent.
Sounds like (no pun intended) your digital audio interface is not set up correctly between your codec and CPU. It's probably best to make sure they are both using the same I2S or PCM modes.
Liam
Exactly, this sounds like when I was sending left-aligned serial audio instead of I2S format from ice1724 to the codec. Low volumes were OK, higner distorted.
Pavel.
------------ Původní zpráva ------------ Od: Liam Girdwood lg@opensource.wolfsonmicro.com Předmět: Re: [alsa-devel] Query regarding sampling rates etc Datum: 10.7.2007 23:18:21
On Tue, 2007-07-10 at 19:32 +0530, Pharaoh . wrote:
Hi, This is a very vague question, just thought of asking it after hours of debugging.
I am testing my alsa driver, written for omap 730/850 based board. I am testing it by using aplay.
Despite checking clocks, sampling rates etc many times and after doing many combinations thereof, I cant hear anything more than a noise which changes and becomes more like the original .wav file as I change various params like sampling rates/clocks etc. It becomes close to the actual thing, but not better.
Any idea what are the params I should be tweaking? I know this is h/w dependent.
Sounds like (no pun intended) your digital audio interface is not set up correctly between your codec and CPU. It's probably best to make sure they are both using the same I2S or PCM modes.
Liam
Alsa-devel mailing list Alsa-devel@alsa-project.org http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
On 7/11/07, dustin@seznam.cz dustin@seznam.cz wrote:
Exactly, this sounds like when I was sending left-aligned serial audio instead of I2S format from ice1724 to the codec. Low volumes were OK, higner distorted.
Pavel.
------------ Původní zpráva ------------ Od: Liam Girdwood lg@opensource.wolfsonmicro.com Předmět: Re: [alsa-devel] Query regarding sampling rates etc Datum: 10.7.2007 23:18:21
On Tue, 2007-07-10 at 19:32 +0530, Pharaoh . wrote:
Hi, This is a very vague question, just thought of asking it after hours
of
debugging.
I am testing my alsa driver, written for omap 730/850 based board. I
am
testing it by using aplay.
Despite checking clocks, sampling rates etc many times and after
doing many
combinations thereof, I cant hear anything more than a noise which
changes
and becomes more like the original .wav file as I change various
params like
sampling rates/clocks etc. It becomes close to the actual thing, but
not
better.
Any idea what are the params I should be tweaking? I know this is h/w dependent.
Sounds like (no pun intended) your digital audio interface is not set
up
correctly between your codec and CPU. It's probably best to make sure they are both using the same I2S or PCM modes.
Liam
Alsa-devel mailing list Alsa-devel@alsa-project.org http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
Okay, got it. But in this case wont the data on i2s line get corrupted? I could see correct data being passed on i2s data line, I tried with some unique patterns and the 2's compliment was visible on the data line.
participants (3)
-
dustin＠seznam.cz -
Liam Girdwood -
Pharaoh .