方法1：代码解密
FLASH_OBProgramInitTypeDef OBInit;
__HAL_FLASH_PREFETCH_BUFFER_DISABLE();
HAL_FLASHEx_OBGetConfig(&OBInit);
if(OBInit.RDPLevel ！= OB_RDP_LEVEL_0)
{
OBInit.OptionType = OPTIONBYTE_RDP;
OBInit.RDPLevel = OB_RDP_LEVEL_0;
(void)HAL_FLASH_Unlock();
(void)HAL_FLASH_OB_Unlock();
(void)HAL_FLASHEx_OBProgram(&OBInit);
(void)HAL_FLASH_OB_Lock();
(void)HAL_FLASH_Lock();
}
__HAL_FLASH_PREFETCH_BUFFER_ENABLE();
方法1：STVP 命令行解密
1）如下图配置后，save as unlock.hex
2）通过stvp界面或命令行烧写OPTION BYTE（unlock.hex）。
STVP_CmdLine -port=USB -BoardName=ST-LINK -Device=stm32L073xB -ProgMode=SWD -progress -no_warn_protect -no_loop -FileOption=unlock.hex