Using both I2S and SDIO

[Nico3]

I want to play audio on STM32F4 Discovery board. Audio is stored in SD card which connected by SDIO. 

On discovery board, I see below connections.

I2S3_SCK -- PC10 -- (SCLK) CS43L22

I2S3_SD -- PC12  -- (SDIN) CS43L22

but PC10 & PC12 are also connected to SDIO_D2 and SDIO_CK.  SDIO has no alternate pins. 

Any suggestion on how to move I2S3_SCK and I2S3_SD to PB3 & PB5 alternate pins on discovery board.

[STTwo-32]

Hello @Nico3 

You can use PB5 for I2S3_SCK and the PB3 for I2S3_SCK.

Best Regards.

STTwo-32

[Nico3]

but audio codec CS43L22  is connected to PC10 and P12 as per schematic of discovery board.

[AScha.3]

So you have to cut the trace PC12 to CS43L22 (DIN) and solder a wire to PB5 .

Then SDIO in 1-bit mode is possible. (1-bit mode is fast enough for audio and more easy to get it running than 4-bit)

+

Or try using the spi-mode to access sd-card, dont need the sdio-pins then.

+

Other way to play audio: use the USB -> MSC host , play from usb-stick then .

[STTwo-32 · Accepted solution]

If you are looking to use the CS43L22, you should use the PC10 for I2S3_SCK and PC12 I2S3_SD. I think you will need to move to SPI for your SD card.

Best Regards.

STTwo-32