Modbus RTU从站通信协议在嵌入式系统中的实现

摘要

According to GB/Z 19582, the design method of communication protocol for modbus RTU slave in imbedded system is described. The time sequence of modbus RTU is analyzed in details, and the universal time sequential control scheme is designed, and the key design element is defined, which ensures reliable communication protocol with modbus RTU slave can be implemented with the design method for any imbedded system with different MCU. The configuration of hardware and software resource for modbus RTU slave communication is disclosed with the example of MCU of MCS-51series with simpler function.%依据GB/Z 19582,给出了嵌入式系统中的Modbus RTU从站通信协议的设计方法。详细分析了Modbus RTU的工作时序,设计了通用的时序控制方案,给出了设计要点,保证使用不同MCU的嵌入式系统均能够使用该设计方法实现可靠的Modbus RTU从站通信。以功能较为简单的MCS-51系列MCU为例,给出了实现Modbus RTU从站通信的硬件及软件资源配置方法。