在工业控制Modbus通讯过程中,当数据量较大,站点较多时容易产生通讯异常现象.此外,由于处理器无法从繁忙的数据通讯中解放出来,忽略其他任务,而降低其利用率.文中详细介绍了一种基于Modbus协议的RS485通讯中环形FIFO队列算法,并结合双缓冲区结构,完成对数据的接收与发送.该设计方法不仅使得CPU不在专注于数据通讯而提高其利用率,而且增加了系统的安全性和可靠性.该算法已成功应用于单主站多站点控制系统中,表现出了较高的优越性.%In the process of modbus communication, it was prone to anomaly when the data is large and the site was more. Besides, because of the processer cannot be liberated from the busy communication to ignore other tasks,the utilization of proces-ser was reduced. This paper introduced a kind of circular FIFO queue algorithm in RS485 communication based on Modbus proto-col. Combined with the double buffer structure, sending and receiving data were completed. This design method makes the CPU not only focused on data communication and improve its utilization, but also increase the safety and reliability of the system. And the algorithm has been successfully applied to a multi-site control system, showing a higher superiority.
展开▼
