error in disabling trustzone on B-U585I-IOT02A Discovery Kit

[amolchor25]

Hi team,

I have followed the steps given (407) Disabling TrustZone on STM32U5 - YouTube

while disabling trustzone on B-U585I-IOT02A Discovery Kit it shows below errors in snapshot

Please let me know any solution on this asap !!

Thanks in advance !!

[Imen.D]

Hello @amolchor25,

I recommend you follow the steps to disable the TrustZone as mentioned in the following resources:

• Security:How to disable TrustZone in STM32L5xx devices during development phase
• Arm TrustZone features for STM32L5 and STM32U5 Series application note.

 Imen

[amolchor25]

Thanks for reply @Imen.D !!

Here I have followed the steps mentioned in the video(https://www.youtube.com/watch?v=LG474meMnag), In that first step is select level 0 from option bytes by selecting DC option from Read out Protection by using hot plug mode but I kept in normal mode after that in the programmer the board is not detecting

below is the screen shot when i select the device in hot plug mode but not able to see the option bytes 

let me know if any other option to enable option bytes

here is the error message in the screen shot.

[Aziz BRIGUI]

Hello @amolchor25,

It seems that you forgot the step where you download a TrustZone enabled project to be able to do the regression when booting from user flash. So as suggested by @Imen.D., you can follow Arm TrustZone features for STM32L5 and STM32U5 Series. page 21 (TZEN/RDP regression with a boot from RSS).

Aziz

[amolchor25 · Accepted solution]

Thank you @Aziz BRIGUI !!

I have change the switch SW1 position of B-U585I-IOT02A  board to "1" then I am able to see the Option bytes in the STMCubeProgrammer.

after that I am able to debug the code from STMCubeIDE.

Thank you all for the reply and suggestions !!

[Diane POMABIA]

Hello @amolchor25 

Thanks you for this feedback. For information , There is an article dedicated to this topic for U5: How to disable Trustzone on STM32U5 Series.

Best Regards

Diane