PC并行口I/O扩展的探讨

The I/O Expand Approach of the PC Parallel Port

利用3个TTL集成块,将一个PC并行口扩展成3个I/O口,该电路结构简单、易于实现,配备相应的控制软件后可方便地应用于各种控制电路中.

Using three TTL integrated circuits,we expand the single PC paralled port to three I/O ports.The circuit is simple and easy to realize.Fitted with controlled software,it is convenient to apply to each controlled circuit.