If I want to get 16kHz output sample rate of PDM,then what should I do? How to cofigure the register PDMCLKCTRL and the clock HFCLK? Could you give me more details? An example may be better.
If I want to get 16kHz output sample rate of PDM,then what should I do? How to cofigure the register PDMCLKCTRL and the clock HFCLK? Could you give me more details? An example may be better.
Hello
Unfortunately we do not have an example for the PDM module.
The PDMCLKCTRL should be set so that the PDM generates a clock, which is acceptable for the peripheral hardware you need to receive a PDM signal from.
As an example, if the microphone in question is a invensense INMP621, it accepts clock signals from 1MHz to 3.6MHz. So in this case any of the three clock speeds listed in the nRF52810 should work nicely.
The microphone will then generate a PDM signal whose sampling rate corresponds to the clock chosen, and the PDM module of the nRF52810 will convert this signal to a signal with 15.625kHz, 16.125kHz or 16.672kHz sampling rate depending on which of the three clocks you chose.
Best regards
Jørn Frøysa