RS 485

Common Communication Protocols in Power Systems: RS-232 as a Country Road, RS-485 as a Highway? A Systematic Discussion of Their Differences!

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Common Communication Protocols in Power Systems: RS-232 as a Country Road, RS-485 as a Highway? A Systematic Discussion of Their Differences!

In the previous article, we discussed the differences between Modbus and RS-485, which belong to different layers. If we use a language analogy, then Modbus determines which “language” to use, while RS-485 and RS-232 determine the method of communication, such as face-to-face or telephone communication. In this article, we will discuss the differences between RS-485 … Read more

Complete Guide to RS-485 Interface Circuits: Everything You Need to Know

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Complete Guide to RS-485 Interface Circuits: Everything You Need to Know

This design guide discusses how to design RS-485 interface circuits. It covers the necessity of balanced transmission line standards and provides an example of process control design. The article also discusses line loading, signal attenuation, failure protection, and current isolation under separate headings. 1. Why Balanced Transmission Line Standards are Necessary The focus of this … Read more

Detailed Explanation of RS-232, RS-485, and RS-422

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Detailed Explanation of RS-232, RS-485, and RS-422

RS-232, RS-485, and RS-422 are common serial communication standards, each with unique characteristics and applicable scenarios. Below is a detailed analysis of these three communication standards: 1. RS-232 1. Origin and Purpose: ● Established by the Electronic Industries Alliance (EIA) in 1962. ● Aimed at solving low-speed, short-distance communication issues between early computers and peripheral … Read more

RS-485 Multi-Slave Communication: How to Effectively Avoid Interference Between Devices?

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RS-485 Multi-Slave Communication: How to Effectively Avoid Interference Between Devices?

In scenarios such as industrial automation, building control, and energy monitoring, RS-485 serial communication is widely used for data transmission between devices due to itslong-distance transmission capability, strong anti-interference ability, and support for multi-node communication. Especially in a master-slave structure, RS-485 is an ideal choice for achieving centralized control and distributed sensing. However, during actual … Read more

RS-485 Communication Protocol

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RS-485 Communication Protocol

RS-485 Communication Protocol Overview The typical serial communication standards are RS-232 and RS-485, which define voltage, impedance, etc., but do not specify software protocols. The RS-485 bus standard defines the electrical characteristics of the bus interface, specifically the definitions for two logic states: a positive level between +2V and +6V represents one logic state, while … Read more

How to Choose Pull-Up and Pull-Down Resistors for RS-485?

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How to Choose Pull-Up and Pull-Down Resistors for RS-485?

The RS-485 bus is widely used in communication, industrial automation, and other fields. In practical applications, it is common to encounter questions about whether pull-up and pull-down resistors are needed and what resistance values are appropriate. Below, we will analyze these issues in detail. 1. Why are Pull-Up and Pull-Down Resistors Needed? 1) When the … Read more

Mastering RS-232, RS-485, and RS-422 Standards and Application Design

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Mastering RS-232, RS-485, and RS-422 Standards and Application Design

Follow our official account to receive timely updates on new articles. Introduction: RS-232, RS-485 and RS-422 are standards defined and published by the Electronic Industries Alliance (EIA). EIA is an American industry association focused on developing and promoting standards in the electronics and electrical industries. Among these, RS-485 is highly praised and widely used in … Read more

Introduction to RS-232, RS-422, and RS-485 and Their Differences

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Introduction to RS-232, RS-422, and RS-485 and Their Differences

1. RS-232 RS-232-C is a serial physical interface standard established by the Electronic Industry Association (EIA) in the United States. RS stands for “Recommended Standard,” 232 is the identification number, and C indicates the revision number. Its full name is “Serial binary data exchange interface technology standard between Data Terminal Equipment (DTE) and Data Communication … Read more

Detailed Explanation of Profibus-DP Termination Resistors: Correct Selection and Installation to Ensure Communication Reliability

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Detailed Explanation of Profibus-DP Termination Resistors: Correct Selection and Installation to Ensure Communication Reliability

To build a stable and reliable Profibus-DP network, termination resistors can be considered a “small component with a big role”! Many engineers often overlook their importance, resulting in spending several days troubleshooting inexplicable communication failures, only to find out that it was the termination resistors causing the trouble. Today, we will analyze this seemingly simple … Read more

RS-485 Protocol Overview

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RS-485 Protocol Overview

: Recently, I modified an old device that required communication control applications, from which I derived some insights: 1. FX2N-485-BD is economical to use; A./ (ASCII communication mode, operation, and frequency register address can be easily mistaken, but LRC checksum is easy to obtain)/ B../ (RTU communication mode, operation, and frequency register address is less … Read more