RE: MCLK Frequency not available?

PS_d — Mon, 19 Sep 2022 14:03:02 GMT

Thanks for confirming, Ken.

We forwarded the issue up the chain earlier today.

Piet

RE: MCLK Frequency not available?

Kenneth — Mon, 19 Sep 2022 12:17:02 GMT

Hello,

You can find in the nRF52832 I2S specification that the maximum value for fMCK is 4MHz:
https://infocenter.nordicsemi.com/topic/ps_nrf52840/i2s.html#unique_356353441

In your use case you may consider using the nRF5340 instead, where maximum value for fMCK is 12.288MHz:
https://infocenter.nordicsemi.com/topic/ps_nrf5340/i2s.html#unique_653264788

The nRF5340 also have an improved I2S interface since the MCLK can be dynamically adjusted on-the-fly without stopping/starting the I2S. From the I2S peripheral description of the nRF5340:

The MCK frequency can be adjusted on-the-fly:
- For PCLK32M, by using MCKFREQ
- For ACLK, by adjusting the audio clock source, see CLOCK — Clock control.

Best regards,
Kenneth