FPGA purpose question

[superslot]

hi all,

I have a simple/trivial question about the functionality of the fpga.
I've seen the data sheet of the cirrus codec and also broadcom I2S output ... it seems to me that they should support TDM correctly.

my understanding is that we use the FPGA to handle IS2 between the raspberry and the cirrus coded.

can someone explain what kind of re-formatting is needed?
somehow I don't see the missing link and why we need an fpga to handle the i2s protocol...


thanks in advance