STM32 内部Flash带缓存读写程序源码 [已验证]

STM32 内部Flash带缓存读写程序源码

由于STM32 系列Flash的Erase操作很多是按Page擦除，如果往Flash写入的数据或余数不够一个整Page，那么该Page其他数据也会被擦除掉。
所以这种情况想保持其他未操作数据不变的话，就要做缓存读写，既将要擦除Page的数据全读出来，与新写入的数据Merge后，再写入。这一块目前ST没有给出Demo，需要现写。

注意到Programming in the Flash memory performed by word or half-page 所以，Write API使用了按Word写入

测试程序使用的单片机为STM32L0系列，PageSize为128B，

Memory map如下：

下面是我以前写的API，首先是相关宏定义：

0 Macro

读写API内部调用的是STM32xx_hal_flash.c中的HAL_FLASH_Program API，如果使用不一样的Hal库，可以直接替换下方的Flash_WriteOneWord宏定义：

#define  TRUE    1
#define  FALSE   0

typedef unsigned char   BOOL;       /* boolean data */
typedef unsigned char   FLAG;       /* boolean data */
typedef unsigned char   U8BIT;      /* unsigned 8 bit data */
typedef unsigned short  U16BIT;     /* unsigned 16 bit data */
typedef unsigned long   U32BIT;     /* unsigned 32 bit data */
typedef unsigned long   WORD;       /* unsigned 32 bit data */

#define PAGE_SIZE              FLASH_PAGE_SIZE  

#define Flash_WriteOneWord(a, b)	    HAL_FLASH_Program(FLASH_TYPEPROGRAM_WORD, a, b)
#define Flash_WriteOneHalfWord(a, b)	HAL_FLASH_Program(FLASH_TYPEPROGRAM_HALFWORD, a, b)

1.Flash_Erase

Erase主要负责写入之前清空的操作，由Wirte API判断要Erase多少Page

/*****************************************************************************
 @Name : Flash_Erase
 @Brief : Erase the whole page by NumtoErase
 @Param In : U32BIT StartAddr         
                     uint16_t PageNumtoErase  
 @Param Out : 
 @Return : TURE for Success, FALSE for Failed
 
History      :
  1.Date   : Tuesday, June 04, 2018
    Author   : Howard Xue

*****************************************************************************/
BOOL Flash_Erase(uint32_t StartAddr, uint16_t PageNumtoErase)
{

	if(HAL_FLASH_Unlock() != HAL_OK)
		return FALSE;
	
	uint32_t PageError_Tmp = 0;
	FLASH_EraseInitTypeDef Eras;
	Eras.NbPages = PageNumtoErase;
	Eras.PageAddress = StartAddr;
	Eras.TypeErase = FLASH_TYPEERASE_PAGES;
	
	if(HAL_FLASHEx_Erase(&Eras , &PageError_Tmp) != HAL_OK)
		return FALSE;


	if(HAL_FLASH_Lock() != HAL_OK)
		  return FALSE;

	return TRUE;


}

2. Flash_Read_Byte

/*****************************************************************************
@Name : Flash_Read_Byte
@Brief : Read Internal Falsh data by address
@Param In : uint32_t StartAddr         
                      uint8_t  *ReadBuf
                      uint32_t NumToRead
@Param Out :   uint8_t  *ReadBuf
@Return : TURE for Success, FALSE for Failed
 
History      :
  1.Date   : Tuesday, June 04, 2018
    Author   : Howard Xue

*****************************************************************************/
BOOL Flash_Read_Byte(uint32_t StartAddr, uint8_t  *ReadBuf, uint32_t NumToRead)
{
	if(NumToRead== 0)
		return FALSE;
		
	uint32_t DataNum = 0;
	uint32_t ReadAddress = StartAddr;
	
	while(DataNum < NumToRead)
	{
		*(ReadBuf + DataNum) = *(__IO uint8_t  *)ReadAddress++;
		DataNum++;
	}
		return TRUE;
}

3.Flash_Write_WithBuffer

BufferWrite其实就是先根据要写多少数据，算出相应需Erase的page数，之后将这些Page的数据全读出来，与新要写入的数据合并覆盖后，再写入。这样就实现除了要写入的地址数据，其他的数据不被Erase更改。

注意Wite传入参数如果是U8的需要强制转换成U32

/*****************************************************************************
@Name : Flash_Write_WithBuffer
@Brief : Read Buffer from Flash ,Then Merge New Data and Write
@Param In : uint32_t StartAddr         
                      uint32_t  *pBufferToWrite
                      uint32_t NumToWrite
@Param Out :   uint32_t  *pBufferToWrite
@Return : TURE for Success, FALSE for Failed
 
History      :
  1.Date   : Tuesday, June 04, 2018
    Author   : Howard Xue

*****************************************************************************/
BOOL Flash_Write_WithBuffer(uint32_t StartAddr, uint32_t *pBufferToWrite, uint32_t NumToWrite)
{

	uint8_t PageNumtoErase = 1;//default is erase 1 page.
    uint32_t i;
	uint32_t ReadBuffer_Length = 0;
//	uint8_t ReadBuffer[FLASH_PAGE_SIZE] = {0};

	if(NumToWrite == 0)
		return FALSE;
	
	//GetPageNum to erase
	if(NumToWrite > FLASH_PAGE_SIZE)
	{
		PageNumtoErase = NumToWrite/FLASH_PAGE_SIZE + 1; 
	}

	ReadBuffer_Length = PageNumtoErase*FLASH_PAGE_SIZE;

	U32BIT *pReadBuffer = (U32BIT *)calloc(1, ReadBuffer_Length);
	U32BIT *pReadBufferCount = pReadBuffer;
	
	//1.Read orginal data from flash
	Flash_Read_Byte(StartAddr,(U8BIT *)pReadBuffer,ReadBuffer_Length);

	//2.Merge New Data for Write
	memcpy(pReadBufferCount,pBufferToWrite,NumToWrite);

	//3.Erase whole page
	if(Flash_Erase(StartAddr, PageNumtoErase) != TRUE)
		return FALSE;

	//4.Write Buffer to Flash, Unlock -> write -> lock
	if(HAL_FLASH_Unlock() != HAL_OK)
		return FALSE;
		
    for ( i = 0 ; i < (ReadBuffer_Length/4) ; i++ )
    {
        if(Flash_WriteOneWord(StartAddr + i * sizeof(uint32_t ), *pReadBufferCount) != HAL_OK)
			return FALSE;
		
		pReadBufferCount++;
    }

	 
	if(HAL_FLASH_Lock() != HAL_OK)
		return FALSE;

	 free(pReadBuffer);
	 return TRUE;
	

}

4.Flash_Write_NoBuffer

/*****************************************************************************
@Name : Flash_Write_NoBuffer
@Brief : Write Flash without Buffer
@Param In : uint32_t StartAddr         
                      uint32_t  *pBufferToWrite
                      uint32_t NumToWrite
@Param Out :   uint32_t  *pBufferToWrite
@Return : TURE for Success, FALSE for Failed
 
History      :
  1.Date   : Tuesday, June 04, 2018
    Author   : Howard Xue

*****************************************************************************/
BOOL Flash_Write_NoBuffer(uint32_t StartAddr, uint32_t *pBufferToWrite, uint32_t NumToWrite)
{

	uint32_t PageNumtoErase = 1;//default
    uint32_t i;

	if(NumToWrite == 0)
		return FALSE;
	
	//GetPageNum to erase
	if(NumToWrite > FLASH_PAGE_SIZE)
	{
		PageNumtoErase = NumToWrite/FLASH_PAGE_SIZE + 1; 
	}
	
	//Erase whole page
	if(Flash_Erase(StartAddr, PageNumtoErase) != TRUE)
		return FALSE;
	
		//4.Write Buffer to Flash, Unlock -> write -> lock
	if(HAL_FLASH_Unlock() != HAL_OK)
		return FALSE;
		
    for ( i = 0 ; i < (NumToWrite/4) ; i++ )
    {
		if(Flash_WriteOneWord(StartAddr + i * sizeof(uint32_t ), *pBufferToWrite) != HAL_OK)
			return FALSE;
			
        pBufferToWrite++;
    }

	 	if(HAL_FLASH_Lock() != HAL_OK)
		  return FALSE;

		return TRUE;

}

5. Test

Test程序中，先Flash_Write_NoBuffer将Data全部写入Flash，然后更改几个下次要写入的数值，只写入更改的数据，这样FlashBufferWrite就会仅更新更改的数值，其他数值不变（如果不使用BufferWrite，Flash同一Page其他数据都会被Erase）
注意Wite传入参数如果是U8的需要强制转换成U32





void FlashTest()
{
	U8BIT Data_W[64] = {0xFA,0xFA,0xFE,0xFE,0xFA,0xFA,0xFE,0xFE,0xFA,0xFA,0xFE,0xFE,0xFA,0xFA,0xFE,0xFE,0xFA,0xFA,0xFE,0xFE,0xFA,0xFA,0xFE,0xFE};
	U8BIT Data_R[64] = {0};
    U32BIT FLASH_DATAZONE_BASE_ADDR = 0x08028000; //Address for test

	Flash_Read_Byte（FLASH_DATAZONE_BASE_ADDR, Data_R,sizeof(Data_R));

	Flash_Write_NoBuffer(FLASH_DATAZONE_BASE_ADDR,(U32BIT *)&Data_W[0],sizeof(Data_W));

	Flash_Read_Byte(FLASH_DATAZONE_BASE_ADDR, Data_R,sizeof(Data_R));

	Data_W[0] = 0;
	Data_W[1] = 1;
	//Merge new data and write, ohter data will contained
	Flash_Write_WithBuffer(FLASH_DATAZONE_BASE_ADDR,(U32BIT *)&Data_W[0],4);
	
	Flash_Read_Byte(FLASH_DATAZONE_BASE_ADDR, Data_R,sizeof(Data_R));
}

STM32 内部Flash带缓存读写程序源码 [已验证]