STM32WB55RGV6 – BLE stack stopped working after switching projects (even old examples fail)

[OussamaBousselmi]

Hello,

I am working with an STM32WB55RGV6 on a custom board powered by battery (always connected).

I successfully ran the Proximity example (non-RTOS) with BLE stack before, but after I worked on another project that used BLE stack + FreeRTOS, the BLE stack no longer works — even the old Proximity example stopped advertising.

Current status

• FUS Info (read via CubeProgrammer):

  • FUS State: FUS_IDLE

  • FUS Status: FUS_NO_ERROR

  • FUS Version: v2.1.0.0

  • Wireless Stack Version: v1.23.0.3

  • Stack address: 0x080D0000

  • FUS Operator: v3.1.0

• Option Bytes:

  • RDP = 0xAA

  • SFSA = 0xD0 (0x080D0000)

• Boot config (nBOOT0, nSWBOOT0) 

I already tried:

• Upgrading FUS and reinstalling BLE stack.

• Mass erase + reflashing the Proximity example.

Result: No advertising, no BLE activity.

What is the recommended way to fully recover BLE stack on a custom board (always battery powered) after using another project?

[STTwo-32]

Aslema @OussamaBousselmi W Marahba fel ST Community.

I suggest you to update the FUS and Stack using the .bin files available on the STM32CubeWB V1.23.0 and the STM32CubeProgtammer V2.20.0. After that, Click on the ´Start wireless stack’ button of the STM32CubeProgrammer. Finally, go and upload your application.

Liltek zina.

STTwo-32

[OussamaBousselmi]

Aslema @STTwo-32, aychek :D

thank you for your quick response.
Unfortunately, I have already tried that, but it does not solve the problem.

[FilipKremen]

Hello,

can you please try to debug the project? Any hardfaults?

Also, can you please try to delete the stack before installing a new one?

Thank you.

Best regards,

Filip Kremen

[Remy ISSALYS]

Hello,

Can you please share the SBRV option byte value? 

Best Regards

[OussamaBousselmi]

Hello,

Thanks for your follow-up.

@FilipKremen 
I’ve already deleted the stack and reinstalled a fresh one, but the issue remains unchanged. There are no hardfaults, and the function Adv_Request() is still never reached during execution.

@Remy ISSALYS 
Regarding your request, the SBRV option byte value is set to 0x34000.

Please let me know if there’s anything else I should check or modify.

Best regards,
Oussama.

[OussamaBousselmi · Accepted solution]

Hello, 
it turns out that a full power cycle is mandatory after operations involving FUS, wireless stack installation/removal, or related option-byte changes on the STM32WB series. A simple reset is not enough to properly reinitialize the system.
In my case, I forced the battery to discharge and tested it again, and it works perfectly.
Thank you.

Best regards,
Oussama.

[OussamaBousselmi]

Hello again,
is there another way to perform a full power cycle without draining/disconnecting the battery? 

Best regards,
Oussama.