说明：  本论文提出的“基于PLC的工业以太网控制的实现”，是通过研究工业以太网与西门子S7-300系列PLC，最终实现交通灯信号控制。安装有STEP7软件的上位机通过以太网与CPU315-2DP的以太网部件连接，在CPU315之间实现硬件组态。并在计算机中利用STEP7软件编写程序。利用计时器、比较指令等方法模拟交通灯控制，并将此模拟程序下载到PLC的CPU中，实现基于PLC的工业以太网控制交通灯信号。
(the thesis of "PLC-based control of industrial Ethernet achieve," through research on industrial Ethernet and Siemens S7-300 Series PLC, the ultimate realization of traffic signal control. Installation of the software is STEP7 PC via Ethernet and CPU315- 2DP Ethernet connectivity components, CPU315 between hardware configuration. And in the computer software used STEP7 programming. Use timers, compare instructions simulation methods such as traffic lights control, this simulation program will be downloaded to the PLC CPU, PLC-based control of industrial Ethernet traffic light signals.)