PC机和以太网转串口设备通讯例子，Visual Basic 6.0环境。-PC and Ethernet to serial communications equipment example, Visual Basic 6.0 environment.

本设计要求使用微机与可编程控制器通过串行通信接口进行连接，采用VB编写通信应用程序，使微机与可编程控制器进行数据交换-This design requires the use of computer and programmable logic controller through the serial communication interface to connect, using the preparation of communications VB application, so th