Start PDM filter after initialization.

PDM down sampling rate.

PDM gain.

Ch 1 clock polarity.

Ch 0 clock polarity.

Enable stereo mode for channel pair CH0 and CH1.

FIFO Data valid level water-mark.

PDM filter data output format.

Number of PDM channels.

PDM filter order.

PDM clock prescaler, resulting PDM clock is input clock / (prescaler + 1).