Audio_playback_and_record example (STM32F4 Discovery)

[slee.121]

Hi.

First , I'm not good at English.​

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I am testing an example of Audio_palyback_and_recorder of STM32f4 Discovery.

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In the i2S setting of the microphone,

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hAudioInI2s.Init.AudioFreq = 2 * AudioFreq; where, AudioFreq = 16K

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Why did you multiply 2?

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And how do you decide the size of the PCM data buffer after converting the PCM from PDM?

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​Thank you.

Best regards,

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[Tesla DeLorean]

Is that how it deals with paired stereo samples? You'd likely want to look at how the Codec (manual/datasheet) describes frequencies and data sizes, and how they interrelate.

[slee.121]

Thank you for your response.

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Stm32f4 Discovery boards use one microphone.

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I'll look for more data and analyze it.

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Thank you.