MSP430 RTOS CPU clock freq setting do not work

Lin,

The SYSBIOS Boot module only supports 2 options for setting the CPU frequency. 
Option 1:  Don't set it to anything
Option 2:  Set it to 8.192 Mhz.

If you don't want 8.192 Mhz then you should turn off the boost by Boot and in main() setup the clock frequencies as you want.
You can turn off the boost by doing the following:

var Boot = xdc.useModule('ti.catalog.msp430.init.Boot');
Boot.configureDCO = false;

See for more details:  http://processors.wiki.ti.com/index.php/SYS/BIOS_for_the_MSP430

Judah

Lin,

It is possible to change the CPU frequency (called MCLK).  Depending on the frequencies, you might need to also change the core voltage.  SYSBIOS does not provide APIs but you can find some TI examples and driverlib routines to help with this.

If you change MCLK you can call BIOS_setCpuFreq() afterwards so BIOS knows what the updated cpu frequency is.

You need to be careful if, along with the MCLK change, you change ACLK and SMCLK too.  That will cause a problem with any peripherals that are using these two clocks.   Any changes of ACLK and SMCLK before BIOS_start() are OK, if you tell ClockFreqs, but any changes to ACLK or SMCLK after BIOS_start() can cause a problem.

Judah