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STM32H743 HCLK3 frequency error in Clock Configuration for HPRE=1

koyodza
Associate

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

 

 

1 ACCEPTED SOLUTION

Accepted Solutions
STTwo-32
ST Employee

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:

STTwo32_1-1735221426975.png

Best Regards.

STTwo-32

To give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.

View solution in original post

3 REPLIES 3
STTwo-32
ST Employee

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:

STTwo32_1-1735221426975.png

Best Regards.

STTwo-32

To give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.

SofLit
ST Employee

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

SofLit_0-1735222069224.png

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

Hope that answers your question.

To give better visibility on the answered topics, please click on "Accept as Solution" on the reply which solved your issue or answered your question.

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