STM32H743 HCLK3 frequency error in Clock Configuration for HPRE=1

[koyodza]

There are error displays (red markings) in the following cases:

STM32Cube_FW_H7_V1.12.1

STM32H743VIT6

SYSCLK <= 240MHz (actually, for any frequencies from 225.5 to 240MHz)

HPRE Prescaller = 1

 

There are no errors in cases where HPRE >= 2, for example, for SYSCLK = 480MHz.

Please see the screenshot

 

 

[STTwo-32]

Hello @koyodza 

This error means you the clock after HPRe prescaler should be <=225MHz. to be able to set this clock to the max value, you have to go to RCC>Power Regulator Voltage Scale and set it to Power Regulator Voltage Scale 0:

Best Regards.

STTwo-32

[koyodza]

The default value for the Power Regulator Voltage Scale is 2 in this case, and it needs to be changed manually.

Thank a lot STTwo-32

[mƎALLEm]

Hello,

That's normal.

If you need to set the same frequency value for System clock and AXI-AHB, you need to take care of the voltage scale. Please refer to the RM0433 / Table 17. FLASH recommended number of wait states and programming delay

In your case you need to set VOS to 0. The issue will disappear.

Hope that answers your question.