STM32L552ZE has set boot_ Lock and TZNE, and set RDP LEVEL=1, causing a deadlock. How to unlock

[星周.1]

Currently, my program cannot be executed, and it is useless to pull up the boot pin, and STLink cannot be linked. There is a way to reset the chip register boot_lock, TZNE, and RDP? or how to perform full chip erasure?

[Diane POMABIA]

Hi @星宇 周​ 

If i understand well , your sample is lock because your trust zone is Enable and your RDP is in level 1 and you would like to return to the basic configuration of your sample?

If it is the case, please refer to this wiki article : https://wiki.st.com/stm32mcu/wiki/Security:How_to_disable_TrustZone_in_STM32L5xx_devices_during_development_phase.

Regards

DianeP

[星周.1]

Thank you for your help. But my current problem is that I set boot_lock and RDP to 1, so I can not read the chip, nor can I call the system bootloader .

Can I reset the chip to factory settings or erase it completely? Please help me if you can!

[星周.1]

Thank you for your help. But my current problem is that I set boot_lock and RDP to 1, so I can not read the chip, nor can I call the system bootloader .

Can I reset the chip to factory settings or erase it completely? Please help me if you can!

[Diane POMABIA]

Hi @星周.1 

It willl depend. If your chip have in flash area an secure code that jump in non secure zone, you can do the regression by attaching the JTAG . But if it's not the case, you have definetly lost this chip.

Regards

DianeP

[星周.1]

OK,Thank you.I think i have lost this chip.