STM32WB55 Full flash erase made the chip unresponsive

[DaniStUser]

Hello.

I'm part of a team and we are developing an BLE application using the STM32WB55 chip.

We are using an STM32WB55 chip in our board and we also have the ST_Link interface so we can connect to it. We've tested this interface and used it many times without any issue. Also, we made sure that the connection to the ST_Link is stable and it works.

We also have more than 1 ST_Link and all work properly with STM32 chips.

An issue appeared while testing the system bootloader, we wanted to perform a full flash erase to reset the chip as factory, but it became unresponsive.

When connecting it to the STM32CubeProgrammer, the flash memory cannot be read, and when trying to read FUS version or to interact with it, it fails.

Full flash erase shouldn't have done this. What may have caused this?

Is there any way to restore the chip to the factory state?

It's a custom board and it becomes unusable if this chip doesn't work.

[STTwo-32]

Hello @DaniStUser and welcome to the ST Community.

Could you please send a screenshot of the values of your option bytes? Also, are you using the STM32CubeProgtammer V2.19.0 or an older one. If it is an older one, please make sure to try using the last version. Finally, please send a photo of your ST-Link.

Best Regards

STTwo-32

[DaniStUser]

Sorry I accidentally marked the previous answer as the solution, but we still have the problem present.

Here IS an image of the option bytes:

 

 

For erasing the flash we used the version 2.18, but we tested with the latest and got the dame result right now?

Is there any test that we can do in order to see if the chip answers?

EDIT: added more photos of the option bytes

[STTwo-32]

Please send a screenshot of all option bytes.

Best Regards.

STTwo-32