How to operate the real time interrupts in the windows 9x is a difficult problem , because the security mechanisms of the windows system don " t allow win32 applications to operate the interrupts directly . through using vxd technology , the author solved the real time interrupts in the windows environment 在windows9x系统下开发cnc系统的一个难点在于如何实现实时中断。 windows系统是一个多任务操作系统，其安全机制不允许win32程序直接操作中断。作者采用vxd技术，解决了windows环境下的实时中断问题。
The status quo of aerospace computers in our country is that uniprocessor computers are very weak in data management and ca n ' t be reconfigured , and software is difficult to be maintained . so it is necessary to develop a kind of space computer which has high performance , reliability and reconfigurability 而从我国航天计算机的现状来看，单机处理能力低，不具备重构能力，软件的可维护性差，所以有必要设计一种采用实时多任务操作系统的、处理能力强的、高可靠、可重构计算机。
Base on the osi security model , the specific security mechanisms for embedded internet are analyzed , a set of security control protocols named eiscp ( embedded internet security communication protocol ) is developed , which is adapt to the 32bit processor and distributed network construction . 2 . the design of security communication protocol based on hash algorithm and block cipher algorithm suitable for 32bit processor is presented 基于osi安全体系架构，分析了适合为嵌入式internet提供安全服务的安全机制，设计并实现了适合在32位处理器和rtos (实时多任务操作系统)环境下实现的，支持多点访问的嵌入式internet安全通信协议eiscp ( embeddedinternetsecuritycommunicationprotocol ) 。
