• STM32WB family
• Supported boards
  • NUCLEO_WB55RG (NUCLEO-WB55RG)
  • DISCO_WB5MMG (STM32WB5MM-DK)
• BLE
  • MBED-OS support
  • BLE FW
  • BLE FW update
  • BLE FW flashing procedure
  • mbed-trace support

STM32WB family

st.com STM32WB family page

This ST MCU family is dual-core : based on an Arm Cortex-M4 core and an Arm Cortex-M0+ core.

• M4 core is dedicated to application (mbed-os)
• M0 core is dedicated to BLE FW (only binary, source files not provided)

Supported boards

NUCLEO_WB55RG (NUCLEO-WB55RG)

st.com STM32WB55RG MCU page

st.com NUCLEO board page

st.com Pack board page

mbed.com platform page

• Total FLASH is 1MB

But FLASH is shared by M4 and M0 cores, see BLE FW

• RAM: 256 KB
  • SRAM1: 192 KB
  • SRAM2a: 32 KB
  • SRAM2b: 32 KB

SRAM1 is dedicated for M4 core, and then for mbed-os applications.

SRAM2 is dedicated for M0 core and inter CPU communication, and then can not be addressed.

DISCO_WB5MMG (STM32WB5MM-DK)

st.com STM32WB5MMG module page

st.com DISCO board page

mbed.com platform page

• Total FLASH is 1MB

But FLASH is shared by M4 and M0 cores, see BLE FW

• RAM: 256 KB
  • SRAM1: 192 KB
  • SRAM2a: 32 KB
  • SRAM2b: 32 KB

SRAM1 is dedicated for M4 core, and then for mbed-os applications.

SRAM2 is dedicated for M0 core and inter CPU communication, and then can not be addressed.

NB: MBED CLI1 tool can be used thanks to this command:

mbedls -m 0884:DISCO_WB5MMG

BLE

MBED-OS support

BLE feature is based on Cordio stack and API (above HCI) implementation.

Note that the BLE controller firmware running on the cortex-M0 is the same as in STcubeFW solution

• within mbed, the controller will run only the below-HCI part
• within STcubeFW (and STM32WPAN middleware), it can run also up to GATT / GAP layers ...

Official ST Application Note : AN5289: Building wireless applications with STM32WB Series microcontrollers

BLE FW

All available BLE FW for M0 core are provided in ths ST STM32CubeWB repo:

https://github.com/STMicroelectronics/STM32CubeWB/tree/master/Projects/STM32WB_Copro_Wireless_Binaries/STM32WB5x

Default BLE FW in ST boards is stm32wb5x_BLE_Stack_full_fw.bin

• As explained in Release_Notes.html, this FW is flashed at @ 0x080CA000
• Default "mbed_rom_size" in targets.json is then "0xCA000" (808K)

To optimize FLASH size, stm32wb5x_BLE_HCILayer_fw.bin is supported for MBED-OS use case

• As explained in Release_Notes.html, this FW is flashed at @ 0x080E0000
• Then "mbed_rom_size" can be updated to "0xE0000" (896K)

Example in your local mbed_app.json:

    "target_overrides": {
        "NUCLEO_WB55RG": {
            "target.mbed_rom_size": "0xE0000"
        }

BLE FW update

Official ST Application Note : AN5185: ST firmware upgrade services for STM32WB Series

BLE FW flashing procedure

STM32CubeProgrammer needs to be used:

https://www.st.com/en/development-tools/stm32cubeprog.html

Please check the Release Note and complete flashing procedure: https://htmlpreview.github.io/?https://github.com/STMicroelectronics/STM32CubeWB/blob/master/Projects/STM32WB_Copro_Wireless_Binaries/STM32WB5x/Release_Notes.html

• connect the board with ST-LINK
• In the left column, go to "Firmware Upgrade Services"
• "Start FUS"
• "Read FUS infos" => version v1.2.0 is expected
• Firmware Upgrade / "Browse" : select the chosen FW (see above)
• Firmware Upgrade / Start address : depends on the chosen FW (see above)
• Firmware Upgrade / "Firmware Upgrade"
• In the left column, go to "Option bytes"
• User Configuration => "Read"
• User Configuration / enable nSWBOOT0 => "Apply"

mbed-trace support

trace group: BLWB

example:

[INFO][BLWB]: WIRELESS COPROCESSOR FW VERSION ID = 1.11.1
[INFO][BLWB]: WIRELESS COPROCESSOR FW STACK TYPE = 1
[DBG ][BLWB]: mbox_write type:1, len:3
[INFO][BLWB]: TX>> BLE CMD
[DBG ][BLWB]:   Type 0x1
[DBG ][BLWB]:    Cmd 0xc03
[DBG ][BLWB]:    Len 0D]