STM32l476 boot inquiry

[ksd4692]

Hello,

The STM32L476 MCU is not booting, and it seems to be stuck at address 0x08000228, as shown in the attached image.

• It used to boot and work correctly before.
• At some point, it stopped booting and no longer functions as expected.

What could be the reason for this behavior?

[TDK]

There's no image attached. What code is it executing when it's stopped?

A common scenario is where the HSE or LSE crystal doesn't boot up properly. Choosing the right crystal is important there. If that is why it is stuck, see tips here:

Guidelines for oscillator design on STM8AF/AL/S and STM32 MCUs/MPUs - Application note

[ksd4692]

When running in debug mode, it doesn’t stop at a specific line of code but keeps looping endlessly.

[TDK]

What lines of code does it loop through?

[ksd4692]

The code is stuck at the following point after pressing "RUN" in debug mode.

It was working well with the same bootloader, but at some point, it stopped functioning.

The same issue occurs on two identical MCUs.

[TDK]

Disassembly isn't too helpful here. I don't think I can help any more without seeing the code where it's hanging. My guess is the HSE or LSE crystal is failing to start.

[ksd4692]

Problem solved. There was an error in the boot->app process.
Thank you for your response.