RS485通信技术(MAXIM)

1. RS485 Basics

2. Application Issues

3. Maxim RS-485 Overview

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RS-485 标准最初由电子工业协会（ EIA ）于 1983 年制

订并发布，后由 TIA— 通讯工业协会修订后命名为 TIA/

EIA-485-A ，不过工程师还是习惯地称之为 RS-

485 。 RS-485 由 RS-422 发展而来，后者是为弥补 RS-

双向通信能力，即允许多个发送器连接到同一条总线上，

同时增加了发送器的驱动能力和冲突保护特性，扩展了总

线共模范围，这就是后来的 EIA RS-485 标准。

What Is a RS485/RS422 Transceiver?

RS485/RS422 is a Physical Layer Shifts Digital Signals to Differential Analog Signals

and Shifts Differential Analog Signals to Digital Signals

Digital Signal (TTL/CMOS)

Analog Diff. Signals

• RS-422 – Primarily Point-to-Point, often used to