STM32WB5MMG: Both HCI Layer and Full BLE Stack Extended firmware return 0x01 errors after flashing

[fariba-r7]

After flashing firmware to STM32WB5MMG, commands return error codes regardless of which firmware type is flashed:

With HCI Layer firmware (stm32wb5x_BLE_HCILayer_fw.bin):

HCI commands return 0x01 (Unknown HCI Command)

With Full BLE Stack Extended firmware (stm32wb5x_BLE_Stack_full_extended_fw.bin):

aci_gap_set_non_discoverable();       // Returns 0x0C (Command Disallowed)
aci_gap_ext_start_scan(...);          // Returns 0x01 (Unknown HCI Command)
aci_gap_start_observation_proc(...);  // Returns 0x01 (Unknown HCI Command)

Configuration

• Device: STM32WB5MMG
• FUS: 1.2.0
• Both firmware files flashed to 0x080CA000 and verified
• App Config: Adjusted appropriately for each firmware type
• Result: Both report "Wireless Firmware version 1.20.0 build 2"

What Works

• Non-connectable advertising (ADV_NONCONN_IND) works fine with both firmware types
• Basic BLE stack initialization succeeds

1. Why do both firmware types fail to activate despite successful flashing?
2. Is FUS 1.2.0 incompatible with both modern firmware types?
3. What could prevent firmware activation after successful flash verification?
4. Why does advertising work but scanning/HCI commands don't?

The fact that non-connectable advertising works suggests basic BLE functionality exists, but neither HCI commands nor GAP scanning commands are recognized.