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Associate III
April 30, 2024
Question

STM32F407: PLL is not working

  • April 30, 2024
  • 3 replies
  • 1887 views

I have build a code of Mcu driver for STM32F407 DISCOVERY board. During Flashing my HSE or HSI works fine but PLL doesn't works on. I will attach the the mcu.c and mai.c file for your reference.

Kindly have a look into this help me out.

3 replies

waclawek.jan
Super User
April 30, 2024

Your coding style is quite hard to penetrate. 

You may want to try setting up PLL using straightforward writes to RCC registers, first.

Do you set FLASH waitstates?

JW

Associate III
May 3, 2024

Yes, I have set the Flash 

Andrew Neil
Super User
April 30, 2024
A complex system that works is invariably found to have evolved from a simple system that worked.A complex system designed from scratch never works and cannot be patched up to make it work.
Technical Moderator
April 30, 2024

Hi @rohitkumarkv07 

To ensure that your clock configuration is correct and to isolate the issue with your controller,

Create a new project with CubeMX then enable your oscillator and configure your clock tree. 

After that enable an MCO pin to visualize your clock with analyzer/scope.

 

To give better visibility on the answered topics, please click on "Best answer" on the reply which solved your issue or answered your question.Best regards,FBL