基于CPLD的计算机并口EPP模式通讯实现

Implement of Parallel Port Communication in EPP Mode Based on CPLD

基于增强并行口(EPP)的数据通讯系统与基于SPP和RS232接口的数据通讯系统相比较,前者具有更高的数据传输速率。用CPLD开发的计算机并行口EPP模式通讯具备多项优点:高速度、灵活、功能齐全(得益于CPLD丰富的内部资源),引脚自定义为设计PCB板提供极大方便。针对EPP模式的WDM驱动程序设计方案,给出了基于CPLD的EPP模式接口电路的设计实例。

Compared to the digital communicational system based on the SPP and RS232 ports, improved digital communicational system based on parallel ports （EPP） has higher digital communicational speed. The computer parallel ports （telecommunication mode of EPP） developed by CPLD possess lots of advantages： high speed, flexibility, powerful function （which benefits from the various internal resource of CPLD）. Its customer-defined pins make it comfortable to design PCB. The paper discussed the design of WDW driver program which is specific to EPP mode; in the meantime, the paper supplied the practical examples of interface circuits based on EPP mode.