打印口分析及应用扩展

对微机打印口的I／O特性进行了分析,叙述了打印口的各端口读写数据与25针D形接口引脚电平关系、通过一个应用实例,给出打印口的命令输出端口和状态输入端口用于8位数字量输入口时,外部信号与打印口引脚的连接方法及数据读取方法．打印口应用扩展在笔研制开发的“高炮激光射击训练模拟器”项目上得到验证,并收到较好的效果;为笔记本电脑(不能扩充I／O板)用于实时检测和控制开拓一条途径。

The Analysis and Applies Expanding of Printer Interface

I/O's property of the printer interface of microcomputer is analysed, the relation that each port read/write data of printer interface and the 25 needles D shape interface draws the foot level is explained . By way of an application example, give connection method as for external signal and printer interface foot, and method that the data are read taking. When command output port and state input port of the printer interface are used the 8 bit numbers word input ports, the extension of printer interface application gets the certification in the author's developes "air-defence artillery laser shooting training simulator" item, and better effect is received . For the notebook computer ( can not expand I/O's board ), the result can be used monitoring and the control of real time.