Running the Homework for the L5 Board a second time. Now i get errors

[DonPavlov]

Hi.,

Because i wanted to verify if the processes worked as well on my work provided Laptop. I ran the homework a second time.

The TFM Homework of course resulted in mutliple Errors and nothing worked. But now i can't even use the L5 Board anymore. I get no output on the Serial and the usb part shows a fail.txt with the following content:

The interface firmware FAILED to reset/halt the target MCU

Trying to connect the STCubeProgrammer also now fails with: DEV_TARGET_NOT_HALTED

So i can't manually wipe the device and restore it again.

Quick help would be appreciated.

[PYada.1]

Thank you so much @Frantz LEFRERE​ 

I am able to connect it by putting the board in boot mode. My RSS version(read from 0x0BF97FFE) is 0. I have tried to disable the trust zone, but it is not disabling it.

ALso I am following video but I am not able to disable trust zone

[Frantz LEFRERE]

If you're able to connect, you should be able to do a RDP regression. Do you confirm ?

To disable TZEN, you need to have a secure code that launch a non secure code. Once that's on you target, you can change RDP to level 0.5.

Then you should be able to connect (hotplug mode) .

Then at the same time you should change TZEN and RDP level to 0.

[PYada.1]

@Frantz LEFRERE​ ,

I have uploaded nonsecure images using loader images(Generated from TFM test named "tfm_ns_enc_sign.bin"). After that, I Have tried to reduce the RDP level to 0.5, that my board is again not able to connect, Then after I have followed the same procedure, and was able to connect the board again. But I am not able to disable trust Zone. Can you help me with it?

[PYada.1]

Now I am able to flash my normal application (without a bootloader).

The steps are as following

1) Connect the board to STM32 cube programmer

2) Change RDP level to 0 i.e.0xaa

3) Disable trust zone by unchecking TZEN in user configuration of option bytes

4) Click on APply

5) Remove write protection by changing write protection end location > start location

After following above steps I am able load demo application.

@Frantz LEFRERE​ , Thank you so much for your support.