stm32f769i-DISCO audio line in

[Beaulier.Francois]

Posted on November 20, 2016 at 14:50

Hi,

I'am trying to get the audio from WM8994 line input.

The BSP driver seems rather incomplete, it works with the 4 mems mics but not with the line input from the codec.

Is there somewhere any source code example for that ? anyone facing the same problem ?

I can share some code that tries to do playback from line in to headphone out if someone interested.

Regards

Francois 

#stm32f769i-disco-audio-wm8994

[slimen]

Posted on November 21, 2016 at 09:47

Hello,

You can refer to the example under

http://http://www.st.com/content/st_com/en/products/embedded-software/mcus-embedded-software/stm32-embedded-software/stm32cube-embedded-software/stm32cubef7.html

in the path: 

\STM32Cube_FW_F7_V1.5.1\Projects\STM32F769I-Discovery\Applications\Audio\Audio_playback_and_record

You can check how this example was implemented and get inspiration to develop your application, it may helps you. You find more details on how to use the example in the readme.txt file.

Here is the STM32746G-Discovery user manual

http://www.st.com/content/ccc/resource/technical/document/user_manual/f0/14/c1/b9/95/6d/40/4d/DM00190424.pdf/files/DM00190424.pdf/jcr:content/translations/en.DM00190424.pdf

to have more information about Audio hardware features on the board.

You can share your application in our forum, it may be very helpful for Community users. 

Regards

[Beaulier.Francois]

Posted on November 21, 2016 at 13:49

The original post was too long to process during our migration. Please click on the provided URL to read the original post. https://st--c.eu10.content.force.com/sfc/dist/version/download/?oid=00Db0000000YtG6&ids=0680X000006I6pe&d=%2Fa%2F0X0000000bwP%2F7zGzXnfop2P4Pho4q.svQPSb9EMv8_WPtJaiUVeIK.g&asPdf=false

[Brian Kennedy]

Posted on December 06, 2016 at 17:28

Out of curiosity, how noisy is the audio in your line in to headphone out passthrough?  That configuration is unusable on the STM32F746 discovery board due to noise, so I've been considering moving to this dev kit for a proof of concept (even though it has more flash and peripherals than I need).  Thanks.

[Beaulier.Francois]

Posted on December 08, 2016 at 15:34

Unfortunatly i have the same problem, it's very noisy...

[john doe]

Posted on May 28, 2017 at 23:33

Thank you

Beaulier.Francois

https://github.com/ProjectsByJRP/audio_pass-through

[James Anderson]

Posted on March 25, 2018 at 07:36

thanks a lot for posting this code john. did you run into issues with noise on the codec's line in? I get enough noise to make the board unusable for audio processing with the code you posted, and with ST's audio loopback demo (which may be new.) I tried powering the board from an external linear Psu as well. gonna have a look at the hefty datasheet of the WM8994 to see if I can reduce the noise by changing some analog path settings or something.

[Adam L.]

I had a similar problem on my STM32F723E-disco board. Noise level on line-in input was unacceptable. Problem lied in wrong connection between PC and board. Supplying power from phone charger solved this issue. More can be found here: https://forum.cockos.com/showthread.php?t=113721