Solved
Where can I get STM32WBxx_SW_Architecture_and_Design.pdf ?
I read mac_802_15_4_api_wb.c and Inside it mentioned "Check STM32WBxx_SW_Architecture_and_Design.pdf for further information".
I searched this file, but I could not get it.
So,where can I get STM32WBxx_SW_Architecture_and_Design.pdf ?