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Explorer II
September 6, 2024
Solved

STM32L431 brown out.

  • September 6, 2024
  • 2 replies
  • 1063 views

Hello.

How can we enable brown out for this processor and the brown out voltage?

Thank you.

    This topic has been closed for replies.
    Best answer by Tesla DeLorean

    Some mechanics along the lines of..

     // Read the option byte
     FLASH_OBProgramInitTypeDef OBInit;
     HAL_FLASHEx_OBGetConfig(&OBInit);
    
     // Check bitwise if the brownout level is not 3
     if ((OBInit.USERConfig & OB_BOR_LEVEL_3) != OB_BOR_LEVEL_3)
     {
     // Set the brownout level to 3
     OBInit.OptionType = OPTIONBYTE_USER;
     OBInit.USERType = OB_USER_BOR_LEV;
     OBInit.USERConfig |= OB_BOR_LEVEL_3;
    
     HAL_FLASH_Unlock();
     HAL_FLASH_OB_Unlock();
     HAL_FLASHEx_OBProgram(&OBInit);
     // This function needs to be called Unlocked Flash and OB state.
     HAL_FLASH_OB_Launch();
     HAL_FLASH_OB_Lock();
     HAL_FLASH_Lock();
     HAL_FLASH_OB_Launch();
     }

    2 replies

    Graduate II
    September 6, 2024

    Perhaps it's covered in the Reference Manual, or there are examples in the code trees of CubeL4 ?

    Graduate II
    September 6, 2024

    Some mechanics along the lines of..

     // Read the option byte
     FLASH_OBProgramInitTypeDef OBInit;
     HAL_FLASHEx_OBGetConfig(&OBInit);
    
     // Check bitwise if the brownout level is not 3
     if ((OBInit.USERConfig & OB_BOR_LEVEL_3) != OB_BOR_LEVEL_3)
     {
     // Set the brownout level to 3
     OBInit.OptionType = OPTIONBYTE_USER;
     OBInit.USERType = OB_USER_BOR_LEV;
     OBInit.USERConfig |= OB_BOR_LEVEL_3;
    
     HAL_FLASH_Unlock();
     HAL_FLASH_OB_Unlock();
     HAL_FLASHEx_OBProgram(&OBInit);
     // This function needs to be called Unlocked Flash and OB state.
     HAL_FLASH_OB_Launch();
     HAL_FLASH_OB_Lock();
     HAL_FLASH_Lock();
     HAL_FLASH_OB_Launch();
     }
    Super User
    September 6, 2024

    You can adjust it in STM32CubeProgrammer along with other option bytes.

    TDK_0-1725644023758.png