STM32 Read-Out Protection geht nicht?

void __boot FW_UU_Reset(void)

{

    FW_Flash_Busy();

    FLASH->OPTKEYR = FLASH_KEY1;

    FLASH->OPTKEYR = FLASH_KEY2;

    FLASH->CR |= 0x20;  // CR_OPTER_Set

    FLASH->CR |= 0x40;  // CR_STRT_Set

    FW_Flash_Busy();

    FLASH->CR &= 0x1FDF;// CR_OPTER_Reset

    FLASH->CR |= 0x10;  // CR_OPTPG_Set

    OB->RDP = 0x00;  // Read-Out-Protection

    FW_Flash_Busy();

    FLASH->CR &= 0x1FEF;

    *(u32*)0xE000ED0C = 0x05FA0001; // Application Interrupt and Reset Control Register vom Cortex-M3

    while(1);

}