How to access I/O ports based on WDM driver is intensively analyzed on the foundation of hardware protection technology of IOPM and program example is given.

• 在屏蔽位矩阵IOPM硬件保护技术的基础上,重点分析了基于WDM驱动程序对I/O端口的访问方法,并给出了程序实例。