What does Data length and channel length mean both in Master and Slave mode?

[CLeo.1]

Hi guys, been working on an I2S project for a while now and I am having such confusion on this bit registers "CHLEN" and "DATLEN".

In Master mode it seems like CHLEN determines the frequency of the SLCK by

2 * CHLEN length * FS and data length I have no idea what it does

and in slave no idea how they both work as the master will provide these signals now.

I had times where it works with CHLEN = 16bit and DATLENGTH = 16bit same with CHLEN = 32BIT And DATALENGTH = 32bit and I have no idea.

Would anyone please explain to me how these registers purpose and how should they set up?

[waclawek.jan]

The RM is not very clear in the details and it may well be that both these fields are simply ignored in Slave mode.

JW

[Piranha]

To me RM0433 figure 624 (Waveform examples) seems very clear. And as always - why don't you use the much better SAI peripheral? Is it some collective insanity? =)

[CLeo.1]

@Community member​ 

I dont believe these fields are ignored as in slave mode, if I change the datalength from 16 - 32 same with Channel length my audio works, if I leave it at 16 it sounds distorted.

@Piranha​ 

Good suggestion Ill look into it thats for sure, and ill check that RM0433 note