How to change the CPU clock on MXRT595

[Wayne2]

Hello NXP team

Now I used the MXRT 595, I want to change the CPU clock from 192MHz to 96MHz.

I have referred some power examples, I didn't find the interface which can change the CPU clock.

And in the IDE clock table, there are two similar clocks, FRO and system clock. 

The FRO could be changed 192MHz to 96MHz, Is this the right place to modify the CPU clock?

[jay_heng]

You can refer to CLOCK_GetMainClkFreq() function in SDK fsl_clock.c driver to know the clock source of CPU, then set the divider value.

CPU Clk Source from MAINCLKSELA 2'b01 - FRODIVSEL Clock,      CLKCTL0->FRODIVSEL

CPU Clk Source from MAINCLKSELB 2'b01 - Main System PLL Clock,     CLKCTL0->MAINPLLCLKDIV

[Wayne2]

Hi NXP team

We have checked our CPU clock is from the MAINCLKSELB 2'b01 - Main System PLL Clock.

We want to change the CPU clock to 192MHz or 96MHz.

Could you tell me how to change it use the CLKCTL0->MAINPLLCLKDIV?

Thanks!

[jingpan · Accepted solution]

Hi @Wayne2 ,

You can set in this way.

You'd better use config tool to set clock if you are not familiar with RT600 clock tree.

Regards,

Jing