MSP430FR6989: MSP430FR6989 HFXTCLK High Frequency Clock

Hello Tobi,

You can output MCLK on the P4.0 pin or also out SMCLK somewhere.  There is an example close to what you are trying to do called msp430fr69xx_cs_01.c here:http://dev.ti.com/tirex/explore/node?node=ABBcbFOMS6iOgeIh.r-PAg__IOGqZri__LATEST 

This example generates an 8MHz MCLK and SMCLK from the DCO and output SMCLK on P7.4.  You can divide SMCLK by 2 to reach 4MHz or modify it to lower MCLK and output it on P4.0.    

As for the HFXT, this is an input for high-frequency crystal oscillators.  You can drive the MSP430FR6989 clocks with a HF crystal, but it is not always required.

Thanks,

JD