How to configure External SAI MCLK source in Peripherals Config Tool

[gh78731]

I need to connect an I2S ADC to SAI1 on an iMX RT1050. I am currently using a hacked iMX RT1050 EVK as the hardware. The I2S ADC will be the master clock source for all three I2S clocks.  The Peripherals config Tool allows me to set the RX_SYNC clock and the RX_BCLK to an external source, but I can't find any setting to set the SAI1_MCLK to an external clock source.

How and where do I do this?

Is it sufficient to set the SAI1_MCLK pin to input? Or is there more to it than that?

Thanks, --- Graham

[Sabina_Bruce · Accepted solution]

Hello ,

Hope you are doing well.

From my understanding to your description you are using the SAI module as a slave. If this is the case, then when using SAI as a slave, there usually is no need to select an MCLK, because
bit clock and frame sync are generated externally. 

Best Regards,

Sabina