Brief Introduction to UDP UDP is a transport layer protocol, sitting in the same layer as the TCP protocol. However, unlike TCP, UDP does not provide features such as timeout retransmission or error retransmission, meaning it is an unreliable protocol. UDP Protocol Header UDP Port Number Many applications require the use of UDP, so it … Read more
The TCP/IP technology, considered one of the great inventions of the Internet era, has profoundly impacted today’s world. After nearly a month of study and exploration, I have a basic understanding of TCP/IP. Since TCP/IP operates in kernel mode within the OS, many details are not perceptible to users, leading to some confusion about TCP/IP. … Read more
This article is a prequel to “The Ming Dynasty Postman of TCP/IP”, discussing how the ministers of the Ming Dynasty’s cabinet designed the TCP/IP network. During the Tianqi period of the Ming Dynasty, Emperor Zhu Youjiao was obsessed with carpentry and heavily relied on the eunuch Wei Zhongxian, having not attended court for a long … Read more
From: Juejin, Author: Ruheng Link: https://juejin.im/post/6844903490595061767 1. TCP/IP Model The TCP/IP protocol model (Transmission Control Protocol/Internet Protocol) consists of a series of network protocols that form the foundation of the Internet and are the core protocols of the Internet. The reference model based on TCP/IP divides protocols into four layers: Link Layer, Network Layer, Transport … Read more
Basic Concepts of Ethernet Before performing Ethernet communication, it is necessary to understand several basic concepts of Ethernet communication, such as IP address allocation, PC network address and settings, etc. Allocating IP Address If the programming device (such as PC) connects to the factory LAN (or the Internet) using a network card, then the programming … Read more
1. Introduction As application layer developers, the network protocol we most often encounter is typically the transport layer’s TCP (another important protocol at this layer is UDP). However, when it comes to the IP protocol, application programmers are more familiar with the concept of an IP address, and it becomes difficult to delve deeper. This … Read more
When it comes to the protocols we encounter most in computer networks, we cannot ignore the TCP/IP protocol. The TCP/IP protocol is also the most famous protocol on the Internet, so let’s discuss the TCP/IP protocol together. Historical Background of TCP/IP Before the TCP/IP protocol existed, back in the 1960s, many countries and regions recognized … Read more
PXB-6021 is a Modbus to CANopen protocol converter launched by ZLG Zhiyuan Electronics, featuring 1 CAN channel, 1 100M Ethernet, and 1 RS485. This product supports Modbus RTU and Modbus TCP, enabling data conversion from Modbus master to CANopen slave. The PXB-6021 supports up to 12 groups of TPDO and 12 groups of RPDO, and … Read more
Modicon M241 is a compact, high-performance, and scalable mid-range PLC, fully embodying Schneider Electric’s concept of “flexible device control.” It is designed specifically for industrial control applications, primarily targeting engineering project applications, providing high-performance electrical control solutions for logical control, speed control, positioning control, and complex network construction. Lexium 28 is a newly launched bus-type … Read more
Canopen is an open and widely used fieldbus. This article mainly introduces the various products from Schneider that support Canopen communication. Canopen Master Stations: Twido, M238, M258, M241, M251, LMC058/LMC078, M340, Premium (The number of supported slave devices varies for each master station; please refer to the manual for details.) Canopen Slave Stations: ATV312/61/71 IMC … Read more