ModbusRTU通信在CP340系统上的实现.pdf

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2010 年第 08 期,第 43 卷通信技术 ,,2010
总第 224 munications Technology ,Totally
·其他·
Modbus RTU 通信在 CP340 系统上的实现

蒋天伟①, 赵京涛②
(①河北工业大学,天津 300130;②廊坊师范学院,河北廊坊 065001)

【摘要】S7—300/400PLC 在工业控制领域应用较为广泛,基于 S7—300/400PLC 的 Modbus RTU 协议通信数据采集一
般采用 CP341 模块配置 Dongle 的模式实现,系统构建成本较高。采用 CP340 模块配比常州维格 TCPC 协议装换模块,并利用
Modbus ASCII 协议,通过编程实现了面向 ModbusRTU 远程终端的协议通信,在 S7—300/400PLC 在工业控制应用中具有一定
的应用价值。
【关键词】Modbus—RTU;Modbus—ASCII;CP340;传输控制与协议转换
【中图分类号】 【文献标识码】A 【文章编号】1002-0802(2010)08-0253-02

Realization of Modbus munication on CP340 System

JIANG Tian-wei①, ZHAO Jing-tao②
(①Hebei University of Technology, Tianjin 300130, China;②Langfang Normal College, Langfang Hebei 065001, China)

【Abstract】S7-300/400 PLC is wildly applied in industrial measurement and control fields. The date acquisition
based on Modbus RTU protocol is usually realized by CP341 module configurated with Dongle, and however, this is
fairly expensive. So CP340 module with TCPC-based Modbus ASCII protocol is adopted, and the Modbus RTU remote
terminal-munication is thus realized by programming. This technology is of certain value for
S7-300/400PLC in industrial measurement and control application.
【Key words】Modbus-RTU; Modbus-ASCII; CP340; TCPC

0 引言可实现 S7300/400 与 ModbusRTU 远程终端的数据交换。
Modbus 协议作为一种串行总线通信协议,已广泛应用
于工业测控领域