STM32如何检测FLASH写保护

只看该作者 · 2012-8-30 17:19

以前做过STM32的IAP，没有能发现一些问题。可是今天再读IAP的软件包。不明白下面这段代码的原理。

  /* Get the number of block (4 or 2 pages) from where the user program will be loaded */

  BlockNbr = (FlashDestination - 0x08000000) >> 12;



  /* Compute the mask to test if the Flash memory, where the user program will be

     loaded, is write protected */

#if defined (STM32F10X_MD) || defined (STM32F10X_MD_VL)

  UserMemoryMask = ((uint32_t)~((1 << BlockNbr) - 1));

#else /* USE_STM3210E_EVAL */

  if (BlockNbr < 62)

  {

    UserMemoryMask = ((uint32_t)~((1 << BlockNbr) - 1));

  }

  else

  {

    UserMemoryMask = ((uint32_t)0x80000000);

  }

#endif /* (STM32F10X_MD) || (STM32F10X_MD_VL) */





  /* Test if any page of Flash memory where program user will be loaded is write protected */

  if ((FLASH_GetWriteProtectionOptionByte() & UserMemoryMask) != UserMemoryMask)

  {

    FlashProtection = 1;

  }

  else

  {

    FlashProtection = 0;

  }