自动转换收发状态的RS-485信号分配器的设计  

Design of RS-485 Hub for Automatically Switching the Transmitting and Receiving Status

作　　者：张红兵[1] 黄石生[1] 周漪清[1] 

机构地区：[1]华南理工大学机械工程学院,广州510640

出　　处：《电测与仪表》2005年第3期51-54,共4页Electrical Measurement & Instrumentation

摘　　要：RS-485信号分配器将一路RS-485总线扩展成多路输入输出总线,它兼具信号中继、信号隔离、终端数量扩充、拓扑结构扩充等方面的功能。介绍了三种典型的RS-485信号分配器的电路设计。利用偏置电路和反相器使得扩展的收发器能在发送状态和接收状态之间自动转换,因而无论单向还是双向传输,均无需单片机的控制。RS-485 Hub expands one RS-485 bus to multi-channel buses. It can repeat signals, isolate signals, expand number of terminators and topologies etc. Three typical RS-485 Hub circuits are introduced. Transceiver can automatically change between transmitting and receiving status by using bias resistors and reversers, thus Hubs with whether one direction or bidirection needn't microcontrollers.

关 键 词：RS-485 信号 扩展 单向 双向 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]