Click 👆 aboveFollowEngineer Yan Ji and ★ Star Mark ★. Modbus-RTU Protocol The RTU ADU is shown in the figure below. In addition to the core PDU, this ADU contains only two pieces of information. First, the address is used to define the slave device corresponding to the PDU. In most networks, address 0 is … Read more
Introduction MQTT (Message Queuing Telemetry Transport) is a lightweight messaging protocol widely used in the Internet of Things (IoT), mobile applications, and other fields. It is based on a publish/subscribe model, providing an efficient messaging mechanism. This article will provide a detailed analysis of the fixed header, variable header, and payload in the MQTT protocol, … Read more
Recently, while testing the integration of Mobotix cameras with HomeAssistant, I found that the Mobotix camera images could be successfully integrated into HomeAssistant via the Onvif protocol or RTSP. So how can the alarm signals from the Mobotix camera be integrated into HA? Since the Mobotix camera supports the MQTT protocol, and HA also supports … Read more
Click 👆 above to follow Engineer Yan Ji and ★star★. Protocol Definition 1. Modbus is a request-response protocol implemented using a master-slave relationship. 2. The Modbus protocol introduces different application data units to change the packet format used in serial communication or to allow the use of TCP/IP and User Datagram Protocol (UDP) networks. Its … Read more
Recently, I needed to implement an HTTP interface for a project. So, I took this opportunity to explain the relationship between HTTP and sockets, as well as their connection to TCP. First, it’s essential to understand that in the network layer architecture, the HTTP protocol belongs to the application layer, while the TCP protocol belongs … Read more
Author l Hollis Source l Hollis (ID: hollischuang) Since HTTP/1.0 and up to HTTP/2, regardless of how the application layer protocol has improved, TCP has always been the foundation of the HTTP protocol mainly because it provides a reliable connection. However, starting from HTTP 3.0, this situation has changed. Because, in the newly released HTTP … Read more
URL: is a type of URI that identifies an Internet resource and specifies how to operate on or retrieve that resource. It can be identified either through the description of the primary access method or through its “location” on the network. Most URLs follow a standard format that consists of three parts: First part: scheme, … Read more
This article mainly introduces some improvements and new features of HTTP2 compared to HTTP1.1. 1. Shortcomings of HTTP1.1 The HTTP protocol adopts a “request-response” model. When using the normal mode, i.e., non-KeepAlive mode, a new connection must be established for each request/response between the client and server, and the connection is immediately closed after completion … Read more
Click the blue text above to follow us 1xx: Informational This class of status codes indicates a temporary response. The client should be prepared to receive one or more 1xx responses before receiving a regular response. HTTP Status Code Description 100 Continue. 101 Switching Protocols. 2xx: Success This class of status codes indicates that the … Read more
What Is USB? USB is a universal serial bus interface standard used to connect computer systems and external devices for data transmission and power supply. Advantages: High-Speed Transmission: The USB interface provides high-speed data transfer rates, suitable for quickly transferring large volumes of data. Hot Swappable: USB devices can be plugged and unplugged while the … Read more