/* unlock the FMC bank1 operation this function can be used for GD32F10x_XD and GD32F10x_CL with flash more than 512KB.  */
void fmc_bank1_unlock(void)
/* unlock the FMC bank1 operation this function can be used for GD32F10x_XD and GD32F10x_CL with flash more than 512KB.  */
void fmc_bank1_unlock(void)
{
    if((RESET != (FMC_CTL1 & FMC_CTL1_LK))){
        FMC_KEY1 = UNLOCK_KEY0;
        FMC_KEY1 = UNLOCK_KEY1;
    }
}