Microcontroller with some kind of audio I/O capability ?

Ricko · ‎2026-04-15

Split from WiFi or WiFi+BT modules architecture and parts recommendations as that's really a separate question!

I didn’t explain myself very clearly. The part I’m mainly interested in is the audio side — specifically, a microcontroller with some kind of audio I/O capability, such as microphone input and speaker output, for recording (and then saving to uSD - perhaps using DMA if it makes sense). I’ve never worked with microcontrollers for audio recording before, so if such micro is not available, I’m also open to a low-cost solution/architecture that uses external components.

Thank you

mƎALLEm · ‎2026-04-15

Hello,

Look at STM32WBA65I-DK1 board.

STM32WBA65 features only Bluetooth Low Energy. No WIFI available.

From STM32WBA65I-DK1 board schematic:

It uses mems microphone and an audio Codec over SAI interface. Definitely you need an external codec for audio output. There is no audio codec integrated on STM32.

You can refer to the audio example available on the STM32WBA6 Cube package: https://github.com/STMicroelectronics/STM32CubeWBA/tree/main/Projects/STM32WBA65I-DK1/Examples/SAI/SAI_AudioPlay

If you are looking for WIFI you need to add an external module.

PS: other non-wireless MCUs feature SAI interface.

Example STM32F769. Look at the STM32F769-DISCO board schematic:

If are looking for a low cost product, make a search with STM32Finder tool or use the MCU product selector tool and make a search of products having SAI interface and inspire from what I proposed as reference designs.

To give better visibility on the answered topics, please click on "Accept as Solution" on the reply which solved your issue or answered your question.

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Andrew Neil · ‎2026-04-15

AFAIK, No ST MCUs have specific mic input or speaker output - you would have to add external (pre)amplifiers.

Maybe also external ADC/DAC - or a CODEC chip.

Some have I2S, etc for digital audio IO...

eg, see:

AN3997 Audio playback and recording using the STM32F4DISCOVERY

AN3998 PDM audio software decoding on STM32 microcontrollers

The STM32F4DISCOVERY has an external audio CODEC; also STM32F413HDISCOVERY

A complex system that works is invariably found to have evolved from a simple system that worked.
A complex system designed from scratch never works and cannot be patched up to make it work.

mƎALLEm · ‎2026-04-15

Hello,

Look at STM32WBA65I-DK1 board.

STM32WBA65 features only Bluetooth Low Energy. No WIFI available.

From STM32WBA65I-DK1 board schematic:

It uses mems microphone and an audio Codec over SAI interface. Definitely you need an external codec for audio output. There is no audio codec integrated on STM32.

You can refer to the audio example available on the STM32WBA6 Cube package: https://github.com/STMicroelectronics/STM32CubeWBA/tree/main/Projects/STM32WBA65I-DK1/Examples/SAI/SAI_AudioPlay

If you are looking for WIFI you need to add an external module.

PS: other non-wireless MCUs feature SAI interface.

Example STM32F769. Look at the STM32F769-DISCO board schematic:

If are looking for a low cost product, make a search with STM32Finder tool or use the MCU product selector tool and make a search of products having SAI interface and inspire from what I proposed as reference designs.

To give better visibility on the answered topics, please click on "Accept as Solution" on the reply which solved your issue or answered your question.

Andrew Neil · ‎2026-04-15

@mƎALLEm wrote:
only Bluetooth Low Energy.

@Ricko In particular, not Bluetooth "Classic"

A complex system that works is invariably found to have evolved from a simple system that worked.
A complex system designed from scratch never works and cannot be patched up to make it work.

MasterT · ‎2026-04-15

Since you mention low-cost & mic's input, than likely quality 24-bits and low distortion is not required.

You can use internal adc/ dac (almost all ST uCPU have, at least 12-bits, and some even better).

Still mic preamp 'd be necessary, amd power amp to drive speaker.

Eastech · ‎2026-04-16

The vast majority of MCUs do not feature an integrated audio codec.
STM32 + External Audio Codec
Recommended:
WM8960
CS43L22
TLV320AIC Series
WM8960 Stereo Audio Codec Module
A widely used audio codec module that supports both recording and playback, designed for compatibility with the STM32 I2S interface.

Andrew Neil · ‎2026-04-16

@Eastech wrote:
designed for compatibility with the STM32 I2S interface.

You mean, "designed for compatibility with I2S" ?

I2S is an industry standard - not specific to ST or STM32

https://en.wikipedia.org/wiki/I2S

I2S bus specification - NXP (nee Philips)

A complex system that works is invariably found to have evolved from a simple system that worked.
A complex system designed from scratch never works and cannot be patched up to make it work.

Ricko · ‎2026-04-22

Thank you @mƎALLEm for the detailed explanation, schematics and links.

And thank you all for the additional info! :)