After standby LSE not work

[ZZH]

I'm using the STM32G030FP6 in standby mode with WKUP2 for wakeup and the system has a backup battery. I'm facing the following issues:

1. When using the LSI clock, standby entry and WKUP2 wakeup work normally.
2. When using the LSE clock, after entering standby and then waking up with WKUP2, the LSE fails to oscillate. I've already extended the timeout period to 10 seconds, but after a reset, the LSE still does not oscillate, and the system gets stuck at the LSE clock initialization part and reports a hardfault. The LSE starts up normally the first time the system is powered on, but once it goes into sleep mode, the LSE cannot start up again. I referred to the standby routine in the LL_example, which only includes the LSI clock mode, with no LSE clock mode. Is there a demo for the LSE clock mode, or did I miss some configuration?

[Quentin_27]

Hi, i don't think if i can resolve your problem but did you use the PC13 GPIO on your board ?

because on the erratasheet i found this issue:

 https://www.st.com/resource/en/errata_sheet/es0486-stm32g030x6x8-device-errata-stmicroelectronics.pdf

2.2.7 PC13 signal transitions disturb LSE
Description
The PC13 port toggling disturbs the LSE clock.
Workaround
None

QM

[ZZH]

On my system, PC13 is not utilized (STM32G030FP6 doesn't have PC13), and during debugging, I've discovered that I can't enable the LSEON bit of the BDCP register during abnormal startup.

[Kmax18]

Hello @ZZH, I trust that your issue is resolved by now.

Your post suggests that you can successfully put the STM32G0 into Standby Mode. I have difficulties with that, and posted about it (STMG0B1RET output pin does not pull down in Standby Mode) and studied several posts, to no avail.

Not sure if you can share a code snippet? Or perhaps comment on my code? I really appreciate it.