flash的初始化，解锁flash和清除一些flash的异常状态标识

uint16_t MEM_If_Init_FS(void) 

{

    HAL_FLASH_Unlock(); 

    __HAL_FLASH_CLEAR_FLAG(FLASH_FLAG_EOP | FLASH_FLAG_OPERR | FLASH_FLAG_WRPERR | 

                          FLASH_FLAG_PGAERR | FLASH_FLAG_PGPERR | FLASH_FLAG_PGSERR);

}

uint16_t MEM_If_DeInit_FS(void) 

{

    HAL_FLASH_Lock();

}

flash 的檫除操作

uint16_t MEM_If_Erase_FS(uint32_t start_Add,uint32_t end_Add)

{

    /* USER CODE BEGIN 3 */

    uint32_t UserStartSector;

    uint32_t SectorError;

    FLASH_EraseInitTypeDef pEraseInit;

    /* Unlock the Flash to enable the flash control register access *************/

    MEM_If_Init_FS();

    /* Get the sector where start the user flash area */

    UserStartSector = GetSector(start_Add);

    pEraseInit.TypeErase = TYPEERASE_SECTORS;

    pEraseInit.Sector = UserStartSector;

    pEraseInit.NbSectors = GetSector(end_Add)-UserStartSector+1 ;

    pEraseInit.VoltageRange = VOLTAGE_RANGE_3;

    if (HAL_FLASHEx_Erase(&pEraseInit, &SectorError) != HAL_OK)

    {

        /* Error occurred while page erase */

        return (1);

    }

    return (USBD_OK);

    /* USER CODE END 3 */

}

擦除操作,先解锁,然后清空所需flash所在sector。注意这里的sector使用GetSector()函数获取的，是一个整型数字（对于F4就是0~11）。

其中的NbSectors是需要清除的sector的个数。

下面是获取sector的编号

我们先按照用户手册上写的在文件usbd_dfu_if.h中define一些需要用到的sector起始地址

#define ADDR_FLASH_SECTOR_0     ((uint32_t)0x08000000) /* Base @ of Sector 0, 16 Kbyte */

#define ADDR_FLASH_SECTOR_1     ((uint32_t)0x08004000) /* Base @ of Sector 1, 16 Kbyte */

#define ADDR_FLASH_SECTOR_2     ((uint32_t)0x08008000) /* Base @ of Sector 2, 16 Kbyte */

#define ADDR_FLASH_SECTOR_3     ((uint32_t)0x0800C000) /* Base @ of Sector 3, 16 Kbyte */

#define ADDR_FLASH_SECTOR_4     ((uint32_t)0x08010000) /* Base @ of Sector 4, 64 Kbyte */

#define ADDR_FLASH_SECTOR_5     ((uint32_t)0x08020000) /* Base @ of Sector 5, 128 Kbyte */

#define ADDR_FLASH_SECTOR_6     ((uint32_t)0x08040000) /* Base @ of Sector 6, 128 Kbyte */

#define ADDR_FLASH_SECTOR_7     ((uint32_t)0x08060000) /* Base @ of Sector 7, 128 Kbyte */

#define ADDR_FLASH_SECTOR_8     ((uint32_t)0x08080000) /* Base @ of Sector 8, 128 Kbyte */

#define ADDR_FLASH_SECTOR_9     ((uint32_t)0x080A0000) /* Base @ of Sector 9, 128 Kbyte */

#define ADDR_FLASH_SECTOR_10    ((uint32_t)0x080C0000) /* Base @ of Sector 10, 128 Kbyte */

#define ADDR_FLASH_SECTOR_11    ((uint32_t)0x080E0000) /* Base @ of Sector 11, 128 Kbyte */

再在usbd_dfu_if.c文件末尾添加函数:

/**

  * @brief  Gets the sector of a given address

  * @param  Address: Flash address

  * @retval The sector of a given address

  */

static uint32_t GetSector(uint32_t Address)

{

  uint32_t sector = 0;

  if((Address < ADDR_FLASH_SECTOR_1) && (Address >= ADDR_FLASH_SECTOR_0))

  {

    sector = FLASH_SECTOR_0;  

  }

  else if((Address < ADDR_FLASH_SECTOR_2) && (Address >= ADDR_FLASH_SECTOR_1))

  {

    sector = FLASH_SECTOR_1;  

  }

  else if((Address < ADDR_FLASH_SECTOR_3) && (Address >= ADDR_FLASH_SECTOR_2))

  {

    sector = FLASH_SECTOR_2;  

  }

  else if((Address < ADDR_FLASH_SECTOR_4) && (Address >= ADDR_FLASH_SECTOR_3))

  {

    sector = FLASH_SECTOR_3;  

  }

  else if((Address < ADDR_FLASH_SECTOR_5) && (Address >= ADDR_FLASH_SECTOR_4))

  {

    sector = FLASH_SECTOR_4;  

  }

  else if((Address < ADDR_FLASH_SECTOR_6) && (Address >= ADDR_FLASH_SECTOR_5))

  {

    sector = FLASH_SECTOR_5;  

  }

  else if((Address < ADDR_FLASH_SECTOR_7) && (Address >= ADDR_FLASH_SECTOR_6))

  {

    sector = FLASH_SECTOR_6;  

  }

  else if((Address < ADDR_FLASH_SECTOR_8) && (Address >= ADDR_FLASH_SECTOR_7))

  {

    sector = FLASH_SECTOR_7;  

  }

  else if((Address < ADDR_FLASH_SECTOR_9) && (Address >= ADDR_FLASH_SECTOR_8))

  {

    sector = FLASH_SECTOR_8;  

  }

  else if((Address < ADDR_FLASH_SECTOR_10) && (Address >= ADDR_FLASH_SECTOR_9))

  {

    sector = FLASH_SECTOR_9;  

  }

  else if((Address < ADDR_FLASH_SECTOR_11) && (Address >= ADDR_FLASH_SECTOR_10))

  {

    sector = FLASH_SECTOR_10;  

  }

  else

  {

    sector = FLASH_SECTOR_11;  

  }

  return sector;

}

flash写入操作

uint16_t MEM_If_Write_FS(uint8_t *src, uint8_t *dest, uint32_t Len)

{

    /* USER CODE BEGIN 3 */

    uint32_t i = 0;

    for(i = 0; i < Len; i+=4)

    {

        /* Device voltage range supposed to be [2.7V to 3.6V], the operation will

           be done by byte */

        if(HAL_FLASH_Program(FLASH_TYPEPROGRAM_WORD, (uint32_t)(dest+i), *(uint32_t*)(src+i)) == HAL_OK)

        {

            /* Check the written value */

            if(*(uint32_t *)(src + i) != *(uint32_t*)(dest+i))

            {

                /* Flash content doesn't match SRAM content */

                return 2;

            }

        }

        else

        {

            /* Error occurred while writing data in Flash memory */

            return 1;

        }

    }

    return (HAL_OK);

    /* USER CODE END 3 */

}

flash读出操作

uint8_t *MEM_If_Read_FS (uint8_t *src, uint8_t *dest, uint32_t Len)

{

    /* Return a valid address to avoid HardFault */

    /* USER CODE BEGIN 4 */

    uint32_t i = 0;

    uint8_t *psrc = src;

    for(i = 0; i < Len; i++)

    {

        dest[i] = *psrc++;

    }

    return HAL_OK;

    /* USER CODE END 4 */

}