STM32内部flash详解(1)(下)

简介: STM32内部flash详解(1)

2-清除标志位

* @brief  Clears the FLASH's pending flags.
  * @param  FLASH_FLAG: specifies the FLASH flags to clear.
  *          This parameter can be any combination of the following values:
  *            @arg FLASH_FLAG_EOP: FLASH End of Operation flag
  *            @arg FLASH_FLAG_OPERR: FLASH operation Error flag
  *            @arg FLASH_FLAG_WRPERR: FLASH Write protected error flag
  *            @arg FLASH_FLAG_PGAERR: FLASH Programming Alignment error flag
  *            @arg FLASH_FLAG_PGPERR: FLASH Programming Parallelism error flag
  *            @arg FLASH_FLAG_PGSERR: FLASH Programming Sequence error flag
  *            @arg FLASH_FLAG_RDERR: FLASH Read Protection error flag (STM32F42xx/43xxx and STM32F401xx/411xE devices)  
  * @retval None
  */
void FLASH_ClearFlag(uint32_t FLASH_FLAG)
{
  /* Check the parameters */
  assert_param(IS_FLASH_CLEAR_FLAG(FLASH_FLAG));
  /* Clear the flags */
  FLASH->SR = FLASH_FLAG;
}

3-擦除

STM32 擦除可以按照块擦除、扇区擦除、擦除全部扇区这三种情况,从上面就能理解这三个的不同

/**
  * @brief  Erases a specified FLASH Sector.
  *
  * @note   If an erase and a program operations are requested simultaneously, 
  *         the erase operation is performed before the program one.
  *
  * @param  FLASH_Sector: The Sector number to be erased.
  *
  *  @note  For STM32F405xx/407xx and STM32F415xx/417xx devices this parameter can
  *         be a value between FLASH_Sector_0 and FLASH_Sector_11.
  *
  *         For STM32F42xxx/43xxx devices this parameter can be a value between
  *         FLASH_Sector_0 and FLASH_Sector_23.
  *
  *         For STM32F401xx devices this parameter can be a value between
  *         FLASH_Sector_0 and FLASH_Sector_5.
  *
  *         For STM32F411xE devices this parameter can be a value between
  *         FLASH_Sector_0 and FLASH_Sector_7.
  *
  * @param  VoltageRange: The device voltage range which defines the erase parallelism. 
  *          This parameter can be one of the following values:
  *            @arg VoltageRange_1: when the device voltage range is 1.8V to 2.1V,
  *                                  the operation will be done by byte (8-bit)
  *            @arg VoltageRange_2: when the device voltage range is 2.1V to 2.7V,
  *                                  the operation will be done by half word (16-bit)
  *            @arg VoltageRange_3: when the device voltage range is 2.7V to 3.6V,
  *                                  the operation will be done by word (32-bit)
  *            @arg VoltageRange_4: when the device voltage range is 2.7V to 3.6V + External Vpp,
  *                                  the operation will be done by double word (64-bit)
  *  
  * @retval FLASH Status: The returned value can be: FLASH_BUSY, FLASH_ERROR_PROGRAM,
  *                       FLASH_ERROR_WRP, FLASH_ERROR_OPERATION or FLASH_COMPLETE.
  */
FLASH_Status FLASH_EraseSector(uint32_t FLASH_Sector, uint8_t VoltageRange)
{
  uint32_t tmp_psize = 0x0;
  FLASH_Status status = FLASH_COMPLETE;
  /* Check the parameters */
  assert_param(IS_FLASH_SECTOR(FLASH_Sector));
  assert_param(IS_VOLTAGERANGE(VoltageRange));
  if(VoltageRange == VoltageRange_1)
  {
     tmp_psize = FLASH_PSIZE_BYTE;
  }
  else if(VoltageRange == VoltageRange_2)
  {
    tmp_psize = FLASH_PSIZE_HALF_WORD;
  }
  else if(VoltageRange == VoltageRange_3)
  {
    tmp_psize = FLASH_PSIZE_WORD;
  }
  else
  {
    tmp_psize = FLASH_PSIZE_DOUBLE_WORD;
  }
  /* Wait for last operation to be completed */
  status = FLASH_WaitForLastOperation();
  if(status == FLASH_COMPLETE)
  {
    /* if the previous operation is completed, proceed to erase the sector */
    FLASH->CR &= CR_PSIZE_MASK;
    FLASH->CR |= tmp_psize;
    FLASH->CR &= SECTOR_MASK;
    FLASH->CR |= FLASH_CR_SER | FLASH_Sector;
    FLASH->CR |= FLASH_CR_STRT;
    /* Wait for last operation to be completed */
    status = FLASH_WaitForLastOperation();
    /* if the erase operation is completed, disable the SER Bit */
    FLASH->CR &= (~FLASH_CR_SER);
    FLASH->CR &= SECTOR_MASK;
  }
  /* Return the Erase Status */
  return status;
}
/**
  * @brief  Erases all FLASH Sectors.
  *
  * @note   If an erase and a program operations are requested simultaneously, 
  *         the erase operation is performed before the program one.
  * 
  * @param  VoltageRange: The device voltage range which defines the erase parallelism. 
  *          This parameter can be one of the following values:
  *            @arg VoltageRange_1: when the device voltage range is 1.8V to 2.1V,
  *                                  the operation will be done by byte (8-bit)
  *            @arg VoltageRange_2: when the device voltage range is 2.1V to 2.7V,
  *                                  the operation will be done by half word (16-bit)
  *            @arg VoltageRange_3: when the device voltage range is 2.7V to 3.6V,
  *                                  the operation will be done by word (32-bit)
  *            @arg VoltageRange_4: when the device voltage range is 2.7V to 3.6V + External Vpp,
  *                                  the operation will be done by double word (64-bit)
  *  
  * @retval FLASH Status: The returned value can be: FLASH_BUSY, FLASH_ERROR_PROGRAM,
  *                       FLASH_ERROR_WRP, FLASH_ERROR_OPERATION or FLASH_COMPLETE.
  */
FLASH_Status FLASH_EraseAllSectors(uint8_t VoltageRange)
{
  uint32_t tmp_psize = 0x0;
  FLASH_Status status = FLASH_COMPLETE;
  /* Wait for last operation to be completed */
  status = FLASH_WaitForLastOperation();
  assert_param(IS_VOLTAGERANGE(VoltageRange));
  if(VoltageRange == VoltageRange_1)
  {
     tmp_psize = FLASH_PSIZE_BYTE;
  }
  else if(VoltageRange == VoltageRange_2)
  {
    tmp_psize = FLASH_PSIZE_HALF_WORD;
  }
  else if(VoltageRange == VoltageRange_3)
  {
    tmp_psize = FLASH_PSIZE_WORD;
  }
  else
  {
    tmp_psize = FLASH_PSIZE_DOUBLE_WORD;
  } 
  if(status == FLASH_COMPLETE)
  {
    /* if the previous operation is completed, proceed to erase all sectors */
#if defined(STM32F427_437xx) || defined(STM32F429_439xx)  
    FLASH->CR &= CR_PSIZE_MASK;
    FLASH->CR |= tmp_psize;
    FLASH->CR |= (FLASH_CR_MER1 | FLASH_CR_MER2);
    FLASH->CR |= FLASH_CR_STRT;
    /* Wait for last operation to be completed */
    status = FLASH_WaitForLastOperation();
    /* if the erase operation is completed, disable the MER Bit */
    FLASH->CR &= ~(FLASH_CR_MER1 | FLASH_CR_MER2);
#endif /* STM32F427_437xx ||  STM32F429_439xx */
#if defined(STM32F40_41xxx) || defined(STM32F401xx) || defined(STM32F411xE) || defined(STM32F446xx)
    FLASH->CR &= CR_PSIZE_MASK;
    FLASH->CR |= tmp_psize;
    FLASH->CR |= FLASH_CR_MER;
    FLASH->CR |= FLASH_CR_STRT;
    /* Wait for last operation to be completed */
    status = FLASH_WaitForLastOperation();
    /* if the erase operation is completed, disable the MER Bit */
    FLASH->CR &= (~FLASH_CR_MER);
#endif /* STM32F40_41xxx || STM32F401xx || STM32F411xE || STM32F446xx */
  }  
  /* Return the Erase Status */
  return status;
}
/**
  * @brief  Erases all FLASH Sectors in Bank 1.
  *
  * @note   This function can be used only for STM32F42xxx/43xxx devices.
  * 
  * @note   If an erase and a program operations are requested simultaneously, 
  *         the erase operation is performed before the program one.
  * 
  * @param  VoltageRange: The device voltage range which defines the erase parallelism. 
  *          This parameter can be one of the following values:
  *            @arg VoltageRange_1: when the device voltage range is 1.8V to 2.1V,
  *                                  the operation will be done by byte (8-bit)
  *            @arg VoltageRange_2: when the device voltage range is 2.1V to 2.7V,
  *                                  the operation will be done by half word (16-bit)
  *            @arg VoltageRange_3: when the device voltage range is 2.7V to 3.6V,
  *                                  the operation will be done by word (32-bit)
  *            @arg VoltageRange_4: when the device voltage range is 2.7V to 3.6V + External Vpp,
  *                                  the operation will be done by double word (64-bit)
  *  
  * @retval FLASH Status: The returned value can be: FLASH_BUSY, FLASH_ERROR_PROGRAM,
  *                       FLASH_ERROR_WRP, FLASH_ERROR_OPERATION or FLASH_COMPLETE.
  */
FLASH_Status FLASH_EraseAllBank1Sectors(uint8_t VoltageRange)
{
  uint32_t tmp_psize = 0x0;
  FLASH_Status status = FLASH_COMPLETE;
  /* Wait for last operation to be completed */
  status = FLASH_WaitForLastOperation();
  assert_param(IS_VOLTAGERANGE(VoltageRange));
  if(VoltageRange == VoltageRange_1)
  {
     tmp_psize = FLASH_PSIZE_BYTE;
  }
  else if(VoltageRange == VoltageRange_2)
  {
    tmp_psize = FLASH_PSIZE_HALF_WORD;
  }
  else if(VoltageRange == VoltageRange_3)
  {
    tmp_psize = FLASH_PSIZE_WORD;
  }
  else
  {
    tmp_psize = FLASH_PSIZE_DOUBLE_WORD;
  } 
  if(status == FLASH_COMPLETE)
  {
    /* if the previous operation is completed, proceed to erase all sectors */
     FLASH->CR &= CR_PSIZE_MASK;
     FLASH->CR |= tmp_psize;
     FLASH->CR |= FLASH_CR_MER1;
     FLASH->CR |= FLASH_CR_STRT;
    /* Wait for last operation to be completed */
    status = FLASH_WaitForLastOperation();
    /* if the erase operation is completed, disable the MER Bit */
    FLASH->CR &= (~FLASH_CR_MER1);
  }  
  /* Return the Erase Status */
  return status;
}
/**
  * @brief  Erases all FLASH Sectors in Bank 2.
  *
  * @note   This function can be used only for STM32F42xxx/43xxx devices.
  *  
  * @note   If an erase and a program operations are requested simultaneously, 
  *         the erase operation is performed before the program one.
  *  
  * @param  VoltageRange: The device voltage range which defines the erase parallelism. 
  *          This parameter can be one of the following values:
  *            @arg VoltageRange_1: when the device voltage range is 1.8V to 2.1V,
  *                                  the operation will be done by byte (8-bit)
  *            @arg VoltageRange_2: when the device voltage range is 2.1V to 2.7V,
  *                                  the operation will be done by half word (16-bit)
  *            @arg VoltageRange_3: when the device voltage range is 2.7V to 3.6V,
  *                                  the operation will be done by word (32-bit)
  *            @arg VoltageRange_4: when the device voltage range is 2.7V to 3.6V + External Vpp,
  *                                  the operation will be done by double word (64-bit)
  *  
  * @retval FLASH Status: The returned value can be: FLASH_BUSY, FLASH_ERROR_PROGRAM,
  *                       FLASH_ERROR_WRP, FLASH_ERROR_OPERATION or FLASH_COMPLETE.
  */
FLASH_Status FLASH_EraseAllBank2Sectors(uint8_t VoltageRange)
{
  uint32_t tmp_psize = 0x0;
  FLASH_Status status = FLASH_COMPLETE;
  /* Wait for last operation to be completed */
  status = FLASH_WaitForLastOperation();
  assert_param(IS_VOLTAGERANGE(VoltageRange));
  if(VoltageRange == VoltageRange_1)
  {
     tmp_psize = FLASH_PSIZE_BYTE;
  }
  else if(VoltageRange == VoltageRange_2)
  {
    tmp_psize = FLASH_PSIZE_HALF_WORD;
  }
  else if(VoltageRange == VoltageRange_3)
  {
    tmp_psize = FLASH_PSIZE_WORD;
  }
  else
  {
    tmp_psize = FLASH_PSIZE_DOUBLE_WORD;
  } 
  if(status == FLASH_COMPLETE)
  {
    /* if the previous operation is completed, proceed to erase all sectors */
     FLASH->CR &= CR_PSIZE_MASK;
     FLASH->CR |= tmp_psize;
     FLASH->CR |= FLASH_CR_MER2;
     FLASH->CR |= FLASH_CR_STRT;
    /* Wait for last operation to be completed */
    status = FLASH_WaitForLastOperation();
    /* if the erase operation is completed, disable the MER Bit */
    FLASH->CR &= (~FLASH_CR_MER2);
  }  
  /* Return the Erase Status */
  return status;
}

4-编程(数据写入)

注意:STM32写入可以按照字、半字、字节单位写入(这点记住每个厂商写入的字节数有的并不相同,像华大的就和这不太一样)

* @brief  在指定地址上编程双字(64位)。

@note   This function must be used when the device voltage range is from
  *         2.7V to 3.6V and an External Vpp is present.
  *
  * @note   If an erase and a program operations are requested simultaneously, 
  *         the erase operation is performed before the program one.
  * 
  * @param  Address: specifies the address to be programmed.
  * @param  Data: specifies the data to be programmed.
  * @retval FLASH Status: The returned value can be: FLASH_BUSY, FLASH_ERROR_PROGRAM,
  *                       FLASH_ERROR_WRP, FLASH_ERROR_OPERATION or FLASH_COMPLETE.
  */
FLASH_Status FLASH_ProgramDoubleWord(uint32_t Address, uint64_t Data)
{
  FLASH_Status status = FLASH_COMPLETE;
  /* Check the parameters */
  assert_param(IS_FLASH_ADDRESS(Address));
  /* Wait for last operation to be completed */
  status = FLASH_WaitForLastOperation();
  if(status == FLASH_COMPLETE)
  {
    /* if the previous operation is completed, proceed to program the new data */
    FLASH->CR &= CR_PSIZE_MASK;
    FLASH->CR |= FLASH_PSIZE_DOUBLE_WORD;
    FLASH->CR |= FLASH_CR_PG;
    *(__IO uint64_t*)Address = Data;
    /* Wait for last operation to be completed */
    status = FLASH_WaitForLastOperation();
    /* if the program operation is completed, disable the PG Bit */
    FLASH->CR &= (~FLASH_CR_PG);
  }
  /* Return the Program Status */
  return status;
}
/**
  * @brief 在指定地址编程一个字(32位)。
  *
  * @note   This function must be used when the device voltage range is from 2.7V to 3.6V.
  *
  * @note   If an erase and a program operations are requested simultaneously, 
  *         the erase operation is performed before the program one.
  * 
  * @param  Address: specifies the address to be programmed.
  *         This parameter can be any address in Program memory zone or in OTP zone. 
  * @param  Data: specifies the data to be programmed.
  * @retval FLASH Status: The returned value can be: FLASH_BUSY, FLASH_ERROR_PROGRAM,
  *                       FLASH_ERROR_WRP, FLASH_ERROR_OPERATION or FLASH_COMPLETE.
  */
FLASH_Status FLASH_ProgramWord(uint32_t Address, uint32_t Data)
{
  FLASH_Status status = FLASH_COMPLETE;
  /* Check the parameters */
  assert_param(IS_FLASH_ADDRESS(Address));
  /* Wait for last operation to be completed */
  status = FLASH_WaitForLastOperation();
  if(status == FLASH_COMPLETE)
  {
    /* if the previous operation is completed, proceed to program the new data */
    FLASH->CR &= CR_PSIZE_MASK;
    FLASH->CR |= FLASH_PSIZE_WORD;
    FLASH->CR |= FLASH_CR_PG;
    *(__IO uint32_t*)Address = Data;
    /* Wait for last operation to be completed */
    status = FLASH_WaitForLastOperation();
    /* if the program operation is completed, disable the PG Bit */
    FLASH->CR &= (~FLASH_CR_PG);
  }
  /* Return the Program Status */
  return status;
}
/**
  * @brief 在指定地址上编程半字(16位)。
  * @note   This function must be used when the device voltage range is from 2.1V to 3.6V.
  *
  * @note   If an erase and a program operations are requested simultaneously, 
  *         the erase operation is performed before the program one.
  *
  * @param  Address: specifies the address to be programmed.
  *         This parameter can be any address in Program memory zone or in OTP zone. 
  * @param  Data: specifies the data to be programmed.
  * @retval FLASH Status: The returned value can be: FLASH_BUSY, FLASH_ERROR_PROGRAM,
  *                       FLASH_ERROR_WRP, FLASH_ERROR_OPERATION or FLASH_COMPLETE.
  */
FLASH_Status FLASH_ProgramHalfWord(uint32_t Address, uint16_t Data)
{
  FLASH_Status status = FLASH_COMPLETE;
  /* Check the parameters */
  assert_param(IS_FLASH_ADDRESS(Address));
  /* Wait for last operation to be completed */
  status = FLASH_WaitForLastOperation();
  if(status == FLASH_COMPLETE)
  {
    /* if the previous operation is completed, proceed to program the new data */
    FLASH->CR &= CR_PSIZE_MASK;
    FLASH->CR |= FLASH_PSIZE_HALF_WORD;
    FLASH->CR |= FLASH_CR_PG;
    *(__IO uint16_t*)Address = Data;
    /* Wait for last operation to be completed */
    status = FLASH_WaitForLastOperation();
    /* if the program operation is completed, disable the PG Bit */
    FLASH->CR &= (~FLASH_CR_PG);
  }
  /* Return the Program Status */
  return status;
}
/**
  * @brief  在指定地址编程序一个字节(8位)。
  * @note   This function can be used within all the device supply voltage ranges. 
  *
  * @note   If an erase and a program operations are requested simultaneously, 
  *         the erase operation is performed before the program one.
  *
  * @param  Address: specifies the address to be programmed.
  *         This parameter can be any address in Program memory zone or in OTP zone. 
  * @param  Data: specifies the data to be programmed.
  * @retval FLASH Status: The returned value can be: FLASH_BUSY, FLASH_ERROR_PROGRAM,
  *                       FLASH_ERROR_WRP, FLASH_ERROR_OPERATION or FLASH_COMPLETE.
  */
FLASH_Status FLASH_ProgramByte(uint32_t Address, uint8_t Data)
{
  FLASH_Status status = FLASH_COMPLETE;
  /* Check the parameters */
  assert_param(IS_FLASH_ADDRESS(Address));
  /* Wait for last operation to be completed */
  status = FLASH_WaitForLastOperation();
  if(status == FLASH_COMPLETE)
  {
    /* if the previous operation is completed, proceed to program the new data */
    FLASH->CR &= CR_PSIZE_MASK;
    FLASH->CR |= FLASH_PSIZE_BYTE;
    FLASH->CR |= FLASH_CR_PG;
    *(__IO uint8_t*)Address = Data;
    /* Wait for last operation to be completed */
    status = FLASH_WaitForLastOperation();
    /* if the program operation is completed, disable the PG Bit */
    FLASH->CR &= (~FLASH_CR_PG);
  }
  /* Return the Program Status */
  return status;
}

5- 上锁

* @brief  Locks the FLASH control register access
  * @param  None
  * @retval None
  */
void FLASH_Lock(void)
{
  /* Set the LOCK Bit to lock the FLASH Registers access */
  FLASH->CR |= FLASH_CR_LOCK;
}

所以根据以上总结如下步骤(严格来说中间还有一些过程,但是常用的就这几步骤,当然库函数不知这几个,还有获得标志位什么的,这点后面再讲)。

(1) 调用 FLASH_Unlock 解锁;

(2) 调用 FLASH_ClearFlag 清除各种标志位;

(3) 根据起始地址及结束地址计算要擦除的扇区;

(4) 调用 FLASH_EraseSector (或FLASH_EraseAllSectors、FLASH_EraseAllBank1Sectors、FLASH_EraseAllBank2Sectors,一般情况下都是按照扇区删除,有时也会按照块删除)擦除扇区,擦除时按字为单位进行操作;

(5) 调用 FLASH_ProgramWord(或其他都可以) 函数向起始地址至结束地址的存储区域都写入数值

(6) 调用 FLASH_Lock 上锁;

(7) 使用指针读取数据内容并校验。

咱们来看一下官网给出的例子

例子

/* 解锁Flash *********************************************************/
  /* 启用flash控制寄存器访问 */
  FLASH_Unlock();
  /* 擦除用户Flash区域************************************************/
  /* area defined by FLASH_USER_START_ADDR and FLASH_USER_END_ADDR */
  /* 清除挂起的标志(如果有) */ 
  FLASH_ClearFlag(FLASH_FLAG_EOP | FLASH_FLAG_OPERR | FLASH_FLAG_WRPERR |
                  FLASH_FLAG_PGAERR | FLASH_FLAG_PGPERR|FLASH_FLAG_PGSERR);
  /* 获取开始扇区和结束扇区的数量 */
  uwStartSector = GetSector(FLASH_USER_START_ADDR);
  uwEndSector = GetSector(FLASH_USER_END_ADDR);
  /*开始擦除操作 */
  uwSectorCounter = uwStartSector;
  while (uwSectorCounter <= uwEndSector)
  {
    /* 设备电压范围假定为[2.7V ~ 3.6V],操作将通过字完成*/
    if (FLASH_EraseSector(uwSectorCounter, VoltageRange_3) != FLASH_COMPLETE)
    {
      /* 扇区擦除时发生错误。.
        用户可以在这里添加一些代码来处理这个错误  */
      while (1)
      {
      }
    }
    /* 跳到下一个扇区 */
    if (uwSectorCounter == FLASH_Sector_11)
    {
      uwSectorCounter += 40;
    }
    else
    {
      uwSectorCounter += 8;
    }
  }
  /* 按照字写入Flash区 ********************************/
  /* area defined by FLASH_USER_START_ADDR and FLASH_USER_END_ADDR */
  uwAddress = FLASH_USER_START_ADDR;
  while (uwAddress < FLASH_USER_END_ADDR)
  {
    if (FLASH_ProgramWord(uwAddress, DATA_32) == FLASH_COMPLETE)
    {
      uwAddress = uwAddress + 4;
    }
    else
    {
      /* Error occurred while writing data in Flash memory.
         User can add here some code to deal with this error */
      while (1)
      {
      }
    }
  }
  /* Lock the Flash to disable the flash control register access (recommended
     to protect the FLASH memory against possible unwanted operation) */
  FLASH_Lock();

还有一些下章介绍。


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CPU:STM32F103RCT6,LQFP64,FLASH:64KB,RAM:20KB flash起始地址为0x8000000,大小为0x10000(16进制)—>65536字节(10进制)—>64KB RAM起始地址为0x2000000,大小为0x5000(16进制)—>20480字节(10进制)—>20KB
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STM32F103系列单片机的FLASH和RAM大小