Skip to main content
OTudo.1
Associate
November 14, 2021
Solved

LSE enable for STM32WLE5CCU6

  • November 14, 2021
  • 4 replies
  • 2335 views

Hi,

I am trying to activate LSE in a project with STM32WLE5CCU6, the pins PC14 and PC15 are activated, but in the window with clock tree, the RTC clock mux does not alow me to select LSE (it is locked on LSI). This happens even if all other pins are unused. I am using CubeMX version 6.3.0.

Does anybody encounter this problem? I am doing something wrong? Can anyone check?

Thank you

This topic has been closed for replies.
Best answer by Mike_ST

Hello,

Please activate the RTC in the Timers section, and select, "activate clock source".

4 replies

TDK
November 14, 2021

You need to enable the LSE in System Core -> RCC first, then you can select it as a clock source.

"If you feel a post has answered your question, please click ""Accept as Solution""."
OTudo.1
OTudo.1Author
Associate
November 15, 2021

Thank you for answering,

That is exactly how I set it up, I selected Crystal for LSE clock, but in Clock configuration page RTC Clock Mux is still locked.

I had attached the ioc file.

Mike_ST
Mike_STBest answer
ST Technical Moderator
November 15, 2021

Hello,

Please activate the RTC in the Timers section, and select, "activate clock source".

In order to give better visibility on the answered topics, please click on 'Best answer' on the reply which solved your issue or answered your question. 
OTudo.1
OTudo.1Author
Associate
November 15, 2021

Thank you,

Now I understand how to activate it.