CubeMX2, even when doing transmit or receive only I2S, both SDI and SDO are muxed

[av500]

e.g. select I2S with "Master transmit" which should only use I2S_CK, I2S_WS and I2S_SDO, yet the I2S_SDI pin is also muxed and blocked for other use (and both DMA directions are available)

[av500]

with old CubeMX, one could select a custom sample rate:

 

new CubeMX2 only provides a fixed list, it should also allow a user defined sample rate

[Saket_Om]

Hello @av500 

Thank you for bringing this issue to our attention.

I reported this internally.

Internal ticket number: CDM0061115

[Saket_Om]

Hello @av500 

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@av500 wrote:

with old CubeMX, one could select a custom sample rate:

 

new CubeMX2 only provides a fixed list, it should also allow a user defined sample rate

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Audio codec in the market use only frequencies that are listed in CubeMX2. Provide other frequencies does not really make sense according to existing devices.

If the purpose is to fine tune the real frequency on I2S bus, then the user can change in the clock tree the source clock frequency of his instance. The real frequency depends directly on this source clock and the computed prescalers. For instance, to reach 11kHZ on C5 product he can choose PSIK as source clock configured at 100MHz and the real frequency will be 11042Hz :

It is also possible to choose APB2 as source clock at 48MHz, then the real frequency will be 11029Hz :

This fine tune step must be done inside clock configuration panel :

If possible, please tell us your specific requirements, and we’ll provide the correct setup for your clock.

[av500]

"...Audio codec in the market use only frequencies that are listed in CubeMX2. Provide other frequencies does not really make sense according to existing devices..."

1. while the data sheets of current audio codecs only lists standard sample rates, they will happily work with whatever rate you feed them within a certain range.
   
   
2. when generating audio content within the CPU, one is free to pick a sample rate and thus might pick one that is exact with regards to what the I2S system can generate. Therefore being able to enter a user sample rate one can see which rate has 0% error.
   
   
3. furthermore, there are use cases where generated I2S signals are not passed to a typical I2S DAC/CODEC.

[Kraal]

I agree with @av500 , it is fine to have presets, but preventing users to select anything that the hardware can perfectly do is counter productive.

I can see situations where CubeMX2 is used as an evaluation tool to assess if the C5 family (for now) can be a good fit for a specific task, here generating a non standard I2S clock frequency for whatever reason.