STM32 going into system memory area when debugging starts

[alexxs]

Hi,

I'm running a fresh board on an STM32L431RCT6. I'm able to successfully run and debug a simple application that I created with STM Cube, but, when flashing our ported application (we have moved from Kinetis, due to the chip shortage), the stack frame looks like it jumped from 0xFFFF FFFE to 0x800 0008 to 0xFFFF FFF9 and then to 0x1FFF 3EEC. I've shorted PH3/BOOT0 pin to ground and checked the 0x800 0000 memory to make sure the first 8 bytes contain the top of the RAM and the address of the main function. They do.

As you can probably tell, I'm not very familiar with the STM32 architecture, coming from Kinetis.

Thank you!

[DPrie.1]

Hello Alexxs, 

Maybe the answer is late, but something similar happened to me, and maybe this could help someone.

I am using a custom bootloader, and when debugging the application (in 0x8005000, with the vector table displaced) I couldn't restart in debug mode, and I had to go out of the session and debug again.

In my case, I needed to declare the same peripherals (I2C and UARTS) in the bootloader and in the app, that's all!