If you are really stubborn enough to get this audio processing thing going on a STM32 MCU you might have discovered the excellent series of videos by YetAnotherElectronicChannel
He is using one of these relatively cheap i2s boards from Pmod stocked with Cirrus Logic chips. The big advantage of these tiny ADDA convertors is that they don't need any extra programming (by i2c or spi)
Sonically they are not the most brilliant and rather susceptible to all kinds of weird interference. But to get the concept going: just fine!
I will not repeat everything mentioned in his videos about circular buffers or data type casting. So check these first. However, there is some problems:
One of the most commonly used group of STM chips is the STM32F407 (and 405). If you are going to use the HAL libraries (yes, you will) be aware that there is 1 bug and 1 conceptual error in the libraries used in full duplex modus.
For future reference:
1. The DMA complete doesn't trigger the Hal_CompleteCallback
2. Both DMA interrupts (both send and receive) do trigger the Callback (if you get 1. going)
https://github.com/STMicroelectronics/stm32f4xx_hal_driver/issues/1
In my comments to the yetanotherelectronic videos and in the above bug report you can find the work around. Be aware that if you do change the HAL libraries, CubeMX will change them back if you use the cube-regenerate-code options!
Edit feb 2022: somebody did finally rewrite the Hal_i2s_ex libraries..yeee!!
This is one of my early attempts with some never heard of chinese brand of ADDA that do actually work quite well.
Again the mix between 'audiophile' capacitor in THT and SMD components. Which is way more easy nowadays as these PCB manufactures also provide SMD assembly services.