如何为STM32L475板交换FLASH内存中的两个区域？

Question

我正在研究 STM32L475 物联网套件，这是一款 ARM M4 Cortex 设备。我想交换闪存的两个区域。我正在使用的电路板有两个闪存存储区，每个存储区的大小为 512KB.So 我有 1 MB 闪存。我读到要交换闪存的内容，你必须先解锁它，然后擦除它然后写入它并在操作结束后锁定闪存。

还有一个限制，一次只能复制2KB的内存，定义为一页。因此只能逐页复制内存。对于我的应用程序，如果满足某些条件，我必须交换存储在闪存中的应用程序 1 和 2。虽然这两个应用程序都被分配了 384 KB 的内存，但它们实际上使用的内存都比这少（例如 264 KB）。

我尝试按照上述步骤操作，但它不起作用。这是我试过的代码：-

    #define APPLICATION_ADDRESS     0x0800F000
    #define APPLICATION2_ADDRESS    0x0806F800
    #define SWAP_ADDRESS            0x0806F000

    boolean swap(void)
    {
      char *app_1=( char*) APPLICATION_ADDRESS;//points to the 1st address of application1
      char *app_2=(char*) APPLICATION2_ADDRESS;//points to the 1st address of application2

        int mem1 = getMemorySize((unsigned char*)APPLICATION_ADDRESS);//returns the number of bytes in Application1
        int mem2 = getMemorySize((unsigned char*)APPLICATION2_ADDRESS);//returns the number of bytes in Application2
        int limit;
        if(mem1>mem2)
            limit= mem1;
        else
            limit= mem2;

        Unlock_FLASH();

       int lm = limit/2048;

        for(int i=1; i<=lm; i++,app_1+=2048,app_2+=2048)
        {
            int *swap = (int *)SWAP_ADDRESS;

            Erase_FLASH(swap);
            Write_FLASH(app_1, swap);
            Erase_FLASH(app_1);
            Write_FLASH(app_2, app_1);
            Erase_FLASH(app_2);
            Write_FLASH(swap, app_2);
        }

            Lock_FLASH();
        return TRUE;
    }

    void Unlock_FLASH(void)
    {
        while ((FLASH->SR & FLASH_SR_BSY) != 0 );
            // Check if the controller is unlocked already
            if ((FLASH->CR & FLASH_CR_LOCK) != 0 ){
            // Write the first key
            FLASH->KEYR = FLASH_FKEY1;
            // Write the second key
            FLASH->KEYR = FLASH_FKEY2;
            }
    }

    void Erase_FLASH(int *c)
    {
        FLASH->CR |= FLASH_CR_PER; // Page erase operation
    FLASH->ACR = c;     // Set the address to the page to be written
    FLASH->CR |= FLASH_CR_STRT;// Start the page erase

    // Wait until page erase is done
    while ((FLASH->SR & FLASH_SR_BSY) != 0);
    // If the end of operation bit is set...
    if ((FLASH->SR & FLASH_SR_EOP) != 0){
        // Clear it, the operation was successful
        FLASH->SR |= FLASH_SR_EOP;
    }
    //Otherwise there was an error
    else{
        // Manage the error cases
    }
    // Get out of page erase mode
    FLASH->CR &= ~FLASH_CR_PER;
    }

    void Write_FLASH(int *a, int *b)
   {
    for(int i=1;i<=2048;i++,a++,b++)
    {
    FLASH->CR |= FLASH_CR_PG;                   // Programing mode
    *(__IO uint16_t*)(b) = *a;       // Write data

    // Wait until the end of the operation
    while ((FLASH->SR & FLASH_SR_BSY) != 0);
    // If the end of operation bit is set...
    if ((FLASH->SR & FLASH_SR_EOP) != 0){
        // Clear it, the operation was successful
         FLASH->SR |= FLASH_SR_EOP;
    }
    //Otherwise there was an error
    else{
        // Manage the error cases
    }
    }
    FLASH->CR &= ~FLASH_CR_PG;
}

    void Lock_FLASH(void)
    {
        FLASH->CR |= FLASH_CR_LOCK;
    }

这里swap buffer是用来临时存储每页（2KB）作为交换时的缓冲区。此外，变量 limit 存储应用程序 1 和 2 的最大大小，以便在如前所述的内存大小不相等的情况下交换时不会出现错误。所以基本上我是一页一页地交换，一次只有 2 KB。

谁能找出代码中的错误？

谢谢，
舍图

Answer 1

2K 是 2048 字节，而不是 2024。修复整个代码中的增量。

There is another restriction that at a time only 2KB of memory can be copied

还有一个，这些内存块必须对齐到 2KB。

这个地址

#define APPLICATION2_ADDRESS 0x08076400

未正确对齐，它的值应能被 2048 (0x800) 整除。

如何为STM32L475板交换FLASH内存中的两个区域？

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