摘要
RS485接口具有良好的抗噪声干扰性能、长传输距离和多站能力等特点,使其成为工业控制的首选串行接口。嵌入式系统中也广泛采用RS485接口作为设备控制的串行接口。RS485采用两线差分的接线方式进行串口数据的传输。由于发送和接收都是采用这两根差分线进行,因此它是半双工工作模式。基于RS485的特点,分别讲述了通过硬件方式和软件方式来实现RS485发送和接收方向的切换,重点解决了DM8168嵌入式平台上软件实现RS485方向切换的功能。
RS485 interface with good noise immunity,long transmission distance and multi-station capacity and other characteristics, makes it the first choice for industrial control serial interface.It is also widely used in embedded systems as a serial interface to control the device.Two-wire differential wiring mode is used in RS485 for serial data transmission.Sending and receiving are carried out using these two differential lines,so it is half-duplex mode.Based on the characteristics of RS485,this paper describes the way through hard-ware and software means to achieve the switch.This article focuses on RS485 direction switching function with the embedded platform DM8168.
出处
《单片机与嵌入式系统应用》
2014年第4期13-16,共4页
Microcontrollers & Embedded Systems