程序 DEMOCRW 和 DEMOPRO 是用于学习 80X86 CPU 的保护模式特性，核心都在常规内存中，方便查看内部数据和堆栈。

本程序必须运行在纯 DOS 下（如 Windows 98 的 启动 DOS ），运行后驻留内存，再运行 DEBUG 实验。

出现保护异常会用黑底黄字显示当前信息（错误代码、中断号（实际是中断号*4）、V86 堆栈）并退出异常程序。

启动时会报告各数据的地址，以及再要显示报告数据的程序地址。

2 RDRXSGEE 程序原为用于 STC89C52 小系统，P0 口输出控制 LED 灯条，P1 接 LED 灯指示，P2 接 4 位键盘。

有特点 可用串口命令，经串口回传 RAM、XRAM、SFG、EEPROM 内容，有利于观察运行时系统的状态，也有助学习。-Program DEMOCRW and DEMOPRO is used to study the protected mode features 80X86 CPU core in conventional memory, internal data and stack for easy viewing.　 This program must be run in pure DOS (such as Windows 98 boot DOS), after running memory-resident, then run DEBUG experiment.　 Protection exception will occur with yellow on black display current information (error code, interrupt number (actually interrupt number* 4), V86 stack) and exit abnormal program.　 Will report addresses data at startup, and then to display the program address the report data. 2 RDRXSGEE program originally used STC89C52 small systems, P0 port output control LED light bar, P1 access LED indicator, P2 pick four keyboard.　 There are features available serial commands via serial backhaul RAM, XRAM, SFG, EEPROM content, is conducive to observe the state of the runtime system will also help to learn.