how to record sound from GPIO analog microphone using STM32MP157C-DK2

[l_Homme]

Hello everyone,

as part of a personal project, i would like to capture analog audio signals from multiple microphones. for this I use a stm32mp157C-dk2 card.

my questions are:

• how to record audio streams from an analog microphone connected to the gpio pins?
• how to interface an analog microphone with a STM32MP157C card

PS: I use openstlinux

Best regards

[PatrickF]

Hello,

maybe this page would be interesting for you: https://wiki.st.com/stm32mpu/wiki/How_to_record_audio

ADC first target is not audio, and need external biasing and pre-amplifier to be used for microphones.

SPI/I2S or SAI are ok, but need external codec (See STM32MP157C-EV1 board).

Digital Microphone should be the more adapted (Using DFSDM). You could have up to 6 microphones with just using 3/4 wires, see AN5027 and STM32MP157C-EV1 board (there is 4 microphones embedded).

Regards