GD32F103RCT6  FMC写入flash  读出来全是ffff  是什么问题？
#define FMC_PAGE_SIZE ((uint16_t)0x800)


#define FMC_WRITE_START_ADDR  ((uint32_t)0x0807F800)  //最后一页2KB
#define FMC_WRITE_END_ADDR    ((uint32_t)0x0807FFFF)   

uint32_t *ptrd;
uint32_t address = 0x00;
uint32_t data0   = 0x01234567U;


/* 计算有多少页要编程或擦除 */
uint32_t PageNum = (FMC_WRITE_END_ADDR - FMC_WRITE_START_ADDR) / FMC_PAGE_SIZE;
/* 计算有多少字要编程或擦除 */
uint32_t WordNum = ((FMC_WRITE_END_ADDR - FMC_WRITE_START_ADDR) >> 2);
/*!
    \brief      main function
    \param[in]  none
    \param[out] none
    \retval     none
*/
void fmc_erase_pages(void)
{
    uint32_t EraseCounter;

    /* unlock the flash program/erase controller */
    fmc_unlock();

    /* clear all pending flags */
    fmc_flag_clear(FMC_FLAG_BANK0_END);
    fmc_flag_clear(FMC_FLAG_BANK0_WPERR);
    fmc_flag_clear(FMC_FLAG_BANK0_PGERR);

    /* erase the flash pages */
    for(EraseCounter = 0; EraseCounter < PageNum; EraseCounter++){
        fmc_page_erase(FMC_WRITE_START_ADDR + (FMC_PAGE_SIZE * EraseCounter));
        fmc_flag_clear(FMC_FLAG_BANK0_END);
                                fmc_flag_clear(FMC_FLAG_BANK0_WPERR);
                                fmc_flag_clear(FMC_FLAG_BANK0_PGERR);
    }

    /* lock the main FMC after the erase operation */
    fmc_lock();
}
void fmc_program(void)
{
    /* unlock the flash program/erase controller */
    fmc_unlock();

    address = FMC_WRITE_START_ADDR;

    /* program flash */
    while(address < FMC_WRITE_END_ADDR){
        fmc_word_program(address, data0);
                                fmc_halfword_program(address,data0);
        address += 2;
        fmc_flag_clear(FMC_FLAG_BANK0_END);
                                fmc_flag_clear(FMC_FLAG_BANK0_WPERR);
                                fmc_flag_clear(FMC_FLAG_BANK0_PGERR);
    }

    /* lock the main FMC after the program operation */
    fmc_lock();
}


uint16_t gd32fmc_ReadWord(uint32_t addr)
{
        return *(volatile  uint32_t*)addr;
}

主函数
               
                        fmc_erase_pages();
                        fmc_program();
                        printf("%x \r\n",gd32fmc_ReadWord(0x0807f800));
                        //printf("%d \r\n",FMC_READ(FMC_WRITE_END_ADDR));