保护方式程序与实方式程序之间的数据交换

The Exchange of Data between Protection Mode Program and Real Mode Program

随着微机及其操作系统的不断升级和发展，在系统中经常涉及到实方式程序和保护方式程序之间进行切换的问题．本文提出一种用三个子程序来完成这种切换的方法．文中具体介绍了这种从实方式进入保护方式以及从保护方式切换到实方式的子程序结构，介绍了两种方式之间进行数据交换的方法，还给出了具体实现的例子．所述方法对于已有软件成果的继承和发展很有实际意义．

With the development of microcomputer and it's operating system, we often deal with the switchover between red mode program and protection mode program. In this paper we use three subprograms to accomplish this switchover. The structures of these subprograms and the method of data exchange between the two modes are physically introduced along with an example. The method provided in this paper has very practical meaning for the succeeding and development of many available sofeware achivements.