Inconsistent Coprocessor Flashing Behavior on STM32WB5MMG with Zephyr

[axel_le_programmeur]

Hello, I am currently programming on an STM32WB5MMG microcontroller using Zephyr, and I'm facing an issue with flashing the coprocessor. I am using STM32CubeProgrammer to flash the firmware stm32wb5x_BLE_HCILayer_extended_fw.bin. However, after flashing, the microcontroller gets stuck in Zephyr's bt_enable function, which tries to communicate with the coprocessor. After repeating the flashing process several times, the program sometimes works, but I am unsure why the behavior is inconsistent, even though I am using the exact same procedure. Do you know the cause of this issue, and could you suggest a solution to ensure the flashing procedure works every time?

[STTwo-32]

Hello @axel_le_programmeur and welcome to the ST Community 

Have you clicked on the "Start Wireless Stack" button after updating the stack. Also, have you installed the .bin file from the STM32CubeWB V1.22.0.

Best Regards.

STTwo-32

[Sarra.S]

Hello @axel_le_programmeur 

Zephyr wise, you have two options for coprocessor binaries: 'Full stack' and 'HCI Layer'. These binaries are available in the STM32WB Cube packages under Projects/STM32WB_Copro_Wireless_Binaries/STM32WB5x/.

Also, to check for compatibility with your binary version, refer to hal_stm32:lib/stm32wb/README.rst. 

Please note that starting from STM32WB Cube package V1.13.2, 'Full stack' binaries are no longer compatible with Zephyr. Therefore, you can only use the 'HCI Only' versions on the M0 side.

Hope that helps!