TDM pins, which to use

[sonaben]

Hi,

What are the specific characteristics of the TDM pins for the Teensy 4.1?
If I wanted to generate another TDM signal on top of the the embedded ones, which pins should I use?
I guess it may have to do with the PLL but I don't know enough to understand what is involved.

Thanks, Ben

 

[PaulStoffregen]

I don't quite understand what you mean by "generate another TDM signal on top of the the embedded ones". While being specific about technical matters is always good, this sort of question might be easier to understand if you gave the context of what sort of project you're try to create.

But I can tell you all of the existing TDM support in the audio library runs in master mode, where Teensy generates all the clock signals. There is currently no slave mode (Teensy receives external clocks) for TDM. But we do have I2S in slave mode, so if you need slave mode TDM, maybe it could be possible with a deep dive into the SAI hardware registers while looking at the I2S slave code for some inspiration.