Why Modbus RTU Always Appears with RS-485?

Why Modbus RTU Always Appears with RS-485?

In the field of industrial communication, Modbus RTU and RS-485 are often mentioned together. Many people mistakenly believe they are the same thing, but in reality, these two concepts are entirely different; they are simply used in close conjunction in industrial control. What is RS-485? RS-485 is a physical layer communication standard that defines how … Read more

In-Depth Analysis of MODBUS Protocol: Understanding Serial Communication Transmission (What are the Differences Between MODBUS RTU and MODBUS ASCII?)

In-Depth Analysis of MODBUS Protocol: Understanding Serial Communication Transmission (What are the Differences Between MODBUS RTU and MODBUS ASCII?)

Click to follow and stay on track in your learning journey! Last time, we delved into the core elements of the MODBUS protocol. I wonder if you have memorized those key points and successfully established a foothold in the world of MODBUS? If you haven’t fully digested the information yet, make sure to review it … Read more

How to Select TVS Diodes for RS-232, RS-485, and CAN Based on Rated Voltage

How to Select TVS Diodes for RS-232, RS-485, and CAN Based on Rated Voltage

In many industrial and automotive applications, protecting interface transceivers from various electrical overstress events is a major concern. Transient Voltage Suppressor (TVS) diodes are commonly used for this purpose as they can clamp voltage spikes by creating a low-impedance current path. The electrical characteristics of TVS diodes are determined by several process factors. These parameters … Read more

Complete Guide to RS-485 System Design

Complete Guide to RS-485 System Design

【Motor Drive | 5G RF | Signal Conditioning | Circuit Design | Power Supply Design | Circuit Layout | High-Speed Interfaces】Join the AI Robot group to access the above practical technical documents, and interact with industry peers👆👆👆The purpose of this application report is to introduce the key aspects of RS-485 system design, providing a comprehensive … Read more

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

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

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

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?

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

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?

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