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一、概述在现代化的工业自动控制系统中往往要对过程的各种参数进行测量及控制,在现代的大型计算机系统中一般都是多个用户同时使用同一台计算机。所有这些应用场合中都存在着大量的信息传递和人机通信。在这些过程中通常消息和数据是以拜特或字符的形式串行传输的。每一参数的测量控制电路或每一计算机用户的信息连接一般采用EIA的RS—232C标准。 RS—232C标准是串行数据传输的接口
I. Overview In the modern industrial automation systems often have to process a variety of parameters to measure and control, in modern large-scale computer systems are generally multiple users simultaneously using the same computer. In all these applications there is a great deal of information transfer and human-machine communication. Often, messages and data are transmitted serially in the form of Beit or characters during these processes. The measurement control circuit for each parameter or the information connection for each computer user generally uses the EIA RS-232C standard. The RS-232C standard is the serial data transfer interface