STM32F4(Flash读保护)


转载来源：STM32F4(Flash读保护)



1，目的
        在实际的产品发布中，如果不对储存在单片机Flash中的程序做一些保护的话，就有可能被一些不法公司，通过仿真器（J-Link，ST-Link等）把Flash中的程序读取回来，得到bin文件或hex文件，然后去山寨产品。所以我们需要对程序进行保护，一种比较简单可靠的方法就是把Flash设置成读保护。

2，开发环境
        1，适用芯片：STM32F4全部芯片
        2，固件库：STM32F4xx_DSP_StdPeriph_Lib_V1.8.0
        3，IDE：MDK517

3，程序源码
[mw_shl_code=c,true]/****************************************************************
* Function:    Flash_EnableReadProtection
* Description: Enable the read protection of user flash area.
* Input:
* Output:
* Return:      1: Read Protection successfully enable
*              2: Error: Flash read unprotection failed
*****************************************************************/
uint32_t Flash_EnableReadProtection(void)
{
  /* Returns the FLASH Read Protection level. */
  if( FLASH_OB_GetRDP() == RESET )
  {
    /* Unlock the Option Bytes */
    FLASH_OB_Unlock();
   
    /* Sets the read protection level. */
    FLASH_OB_RDPConfig(OB_RDP_Level_1);
   
    /* Start the Option Bytes programming process. */  
    if (FLASH_OB_Launch() != FLASH_COMPLETE)
    {
      /* Disable the Flash option control register access (recommended to protect
         the option Bytes against possible unwanted operations) */
      FLASH_OB_Lock();
      
      /* Error: Flash read unprotection failed */
      return (2);
    }
  
    /* Disable the Flash option control register access (recommended to protect
       the option Bytes against possible unwanted operations) */
    FLASH_OB_Lock();

    /* Read Protection successfully enable */
    return (1);
  }
  
  /* Read Protection successfully enable */
  return (1);
}

/****************************************************************
* Function:    Flash_DisableReadProtection
* Description: Disable the read protection of user flash area.
* Input:
* Output:
* Return:      1: Read Protection successfully disable
*              2: Error: Flash read unprotection failed
*****************************************************************/
uint32_t Flash_DisableReadProtection(void)
{
  /* Returns the FLASH Read Protection level. */
  if( FLASH_OB_GetRDP() != RESET )
  {
    /* Unlock the Option Bytes */
    FLASH_OB_Unlock();
   
    /* Sets the read protection level. */
    FLASH_OB_RDPConfig(OB_RDP_Level_0);
   
    /* Start the Option Bytes programming process. */  
    if (FLASH_OB_Launch() != FLASH_COMPLETE)
    {
      /* Disable the Flash option control register access (recommended to protect
         the option Bytes against possible unwanted operations) */
      FLASH_OB_Lock();
      
      /* Error: Flash read unprotection failed */
      return (2);
    }
  
    /* Disable the Flash option control register access (recommended to protect
       the option Bytes against possible unwanted operations) */
    FLASH_OB_Lock();

    /* Read Protection successfully disable */
    return (1);
  }
  
  /* Read Protection successfully disable */
  return (1);
}[/mw_shl_code]