摘要
以一种污水监测系统为例,提出了采用S7-200型PLC作为现场数据采集终端的方案,通过PLC的自由口模式,同时实现了与上位机的自定义协议通信以及与电磁流量计的HART协议通信。介绍了PLC的通信参数设置和程序设计,给出了自定义串行通信协议格式以及部分采用VB6.0编写的上位机串行通信程序。
Taking a waste-water monitoring system as an example,the method which used S7-200 PLC as field data collection terminal was proposed.The communication between PLC and host computer with user-defined protocol,as well as between PLC and electromagnetic flowmeter based on HART protocol were achieved by PLC＇s freeport mode.The communication parameter settings and program design of PLC were introduced and the user-defined serial communication protocol and some upper-computer serial communication program programmed by VB6.0 were given.
出处
《仪表技术与传感器》
CSCD
北大核心
2010年第10期69-71,共3页
Instrument Technique and Sensor
