STM32CubeProgrammer cannot connect to board using ST-LINK V3

[SedCore]

Hi, I get the below error when trying to connect to my B-U585I-IOT02A board in "Hot plug" and "Hardware reset" modes, whatever is the frequency. I get the same error even with BOOT0 High.

I'm using STM32Cube Programmer v2.17.0

Connection is successful only when I keep on pressing the reset button, but there is no option byte set and any attempt to set option bytes fails.

Thanks in advance for your support.

[AScha.3]

Hi,

try with these settings:

SWD...software reset, debug in low power mode..

[SedCore]

Still this error:

[AScha.3]

Hmmm...

Was it working before ?

Did you set some protection or debug authent. ?

Power consumption ...normal ? Gets something hot ?

[SedCore]

Yes, it was working fine. I got this error after running the regression.sh script in the TF-M application as described in UM2851, which failed.

I don't know if this set some protection or debug auth. But power consumption is normal I think, since nothing is hot.

[AScha.3]

Oo...so try with hot plug mode.

Good luck.

Get any messages on serial terminal ?

Or did you activate RDP level 2 ?  Then be more careful with next board.

Debug: the debug protection consists in deactivating the DAP (debug access port). Once deactivated, the
JTAG pins are no longer connected to the STM32U5 internal bus. DAP is automatically disabled with RDP
level 2.

[SedCore]

I'm already working in Hot Plug mode, Hardware reset, as I mentioned in my initial post.

And there is nothing appearing on the serial terminal.

No, I didn't activate RDP level 2, I know it's a critical feature.

As I said in my initial post, connection is successful only when I keep on pressing the reset button, but there is no option byte set and any attempt to set option bytes fails. And the flash memory is fully erased. Is there anything we can do or modify in this board state to bring it back to its normal state?

[AScha.3]

Sorry, dont know. I always stay away from this protection-secure-never-know-what-happens experience.

+ yes, i read, what you wrote; cannot access bootloader also..so looks like "protected".

So my last 2 ideas :try connect under reset

- or ask STM for support ->

https://ols.st.com/s/

stm support

[TDK]

> is no option byte set

Given that each bit in the option bytes can only be 0 or 1, what does this mean? Screenshot?

Sounds like the board is doing something before the debugger can connect.

[SedCore]

@AScha.3 

- Trying to connect Under Reset raises the following error:

- Okay, thanks for having tried to help solve this issue.