MSP430FR5969: HWI dynamic enable/disable

It is better to do it to reduce any risk that some noise or unexpected operation in the r/w enabled FRAM area. But it is ok if the interrupt can't be disabled.

How about uart? It they should be disabled only at operations before write? DISABLE -something - ENABLED - write?

Disable interrupt--- enable FRAM write permission --- write data into FRAM --- disable FRAM write --- enable interrupt

To disable/enable interrupt you can use the function below

void __disable_interrupt(void);
void __enable_interrupt(void);