With the continuous development of Internet technology in recent years, the integration of electromechanical equipment into the Internet and its remote monitoring have become widely used. Embedded Web-based remote monitoring, building upon traditional remote monitoring by incorporating Web and embedded technologies, offers more powerful functions than traditional remote monitoring and will become the mainstream direction for future remote monitoring technology development. Web technology compensates for the shortcomings of traditional monitoring systems, making the use of Web technology for remote equipment monitoring an increasingly indispensable part of equipment monitoring systems. Web services for embedded devices open up a new field for data acquisition, monitoring, diagnosis, and maintenance of field equipment. An example is the remote monitoring model for industrial washing machines based on embedded Web technology. The concept of embedded Web-based remote monitoring is to implement HTTP services in electromechanical equipment, transforming them into a Web server embedded in the controlled equipment. This provides Internet or LAN users with a Web-based graphical management interface, eliminating the need for dedicated client management software and enabling unified management of various devices connected to the network. Users can directly access the Web server on the electromechanical equipment through existing public communication networks, without geographical limitations, using a standard Web browser as the interface to achieve remote monitoring, diagnosis, and maintenance of field equipment at various nodes in the network. The basic functions of a typical industrial washing machine include: human-machine interface, motor control, valve control, washing machine status detection, temperature detection, and water level detection. To achieve remote monitoring and remote fault diagnosis, the washing machine should also have network capabilities. To achieve intelligent control, meaning the controller can automatically provide the optimal washing plan based on the amount, degree of soiling, and nature of the soiling during the washing process, the washing machine needs turbidity detection and fabric type/weight detection functions. Based on the above analysis, to realize the basic functions of an industrial washing machine as well as its intelligent and networked capabilities, the embedded system must have at least the following interfaces: LCD interface, touchscreen interface (matrix keyboard interface, LED indicator interface), RS-232 or RS485 interface, UART interface, 3 AD inputs, 21 digital outputs, 8 digital inputs (two of which can be used as interrupt sources), and an Ethernet interface. The overall structure diagram of a remote monitoring system for an industrial washing machine based on an embedded web interface is shown in Figure 1. Hardware Design With the development of embedded microprocessors, a series of low-power, high-performance embedded CPUs such as PowerPC, 68K, MIPS, and ARM have emerged. Therefore, a low-cost 32-bit ARM series embedded processor was chosen, which is not only inexpensive but also has low power consumption, fast processing speed, and broad application prospects, making it suitable for remote monitoring needs. In the remote monitoring system for industrial washing machines, the HMS30C7202 (32-bit RISC microprocessor) from Hyundai Corporation of South Korea was selected. This is a high-performance chip with a competitive price-performance ratio. This chip integrates an ARM7TDMI CPU core, a memory management unit (MMU), 8KB of high-speed cache memory, and a write buffer. It also features rich interfaces: support for STN and TFT LCDs, touch screens, matrix keyboards, mice, LED indicators, LAN, CAN, USB, RS-232, RS-485, infrared, 24 relay outputs, 10 digital inputs, 3 analog inputs, and 2 PWM outputs. To achieve remote network monitoring, the system's underlying network interface chip, the CS8900A, and peripheral circuitry are used. In this system, the CS8900A network interface chip operates in 16-bit mode. The hardware block diagram of the intelligent control system for remote monitoring of industrial washing machines is shown in Figure 2. Software Design The core task of software design is to establish an embedded web server on the aforementioned hardware platform to respond to user requests in real time. In addition, intelligent control of the industrial washing machine must be implemented. The industrial washing machine system requires the detection of multiple parameters, using multiple sensors, each with different parameter detection and data transmission methods. Furthermore, many components need to be controlled during the washing process, such as frequency converters and various valves; the relationships between functional modules in the system are complex, with numerous tasks and concurrent relationships between various requirements. Additionally, network functionality is required. Therefore, it is necessary to introduce an embedded operating system. This system selects the μC/OS-II embedded operating system, a multi-tasking, high-real-time open-source operating system, which has been tailored, ported, and supplemented to form a dedicated real-time operating system for industrial washing machines. The network communication protocol TCP/IP adopts the open-source 1wIP protocol stack and has been optimized for specific requirements. To obtain a user-friendly local operating interface, an open-source graphical user interface, μC/GUI, is used, which has excellent interface cooperation with μC/OS-II and comprehensive functions. Therefore, the industrial washing machine intelligent controller software consists of four parts: the real-time operating system μC/OS-II, hardware drivers, API functions, and application programs. The specific structure is shown in Figure 3. The embedded operating system mC/OS-II is an open-source, preemptive, multitasking microkernel RTOS. Each task has a different priority, which can well meet real-time requirements. Compared with other real-time operating systems, mC/OS-II has a simple structure, is easy to port, and is widely used in various fields of industrial control. The main work in porting mC/OS-II (V2.51) to HMS30C7202 was modifying three files related to the ARM architecture: OS_CPU.H, OS_CPU_C.C, and OS_CPU_A.S. OS_CPU.H mainly contains the definitions of compiler-related data types, stack types, and several macro definitions and function descriptions. OS_CPU_C.C contains C functions related to porting, including stack initialization functions and implementations of some hook functions. OS_CPU_A.S contains assembly language functions related to porting, including enabling/disabling interrupts, context switching, clock interrupt service routines, etc. TCP/IP Protocol Stack The system uses the open-source TCP/IP protocol stack LWIP (Light Weight IP). LWIP is an open-source TCP/IP protocol stack for embedded systems developed by the Swedish Institute of Computer Science. The focus of LWIP implementation is to reduce RAM usage while maintaining the main functions of the TCP protocol. Generally, it only requires about 10kB of RAM and about 40kB of ROM to run, making it suitable for use in low-end embedded systems. The LWIP protocol stack was designed with future portability in mind, separating all hardware, OS, and compiler-related parts and placing them in the /src/arch directory. Therefore, implementing LWIP on uC/OS-II involves modifying files in this directory; other files generally do not need modification. This system uses LWIP version 1.1.0. The LWIP porting work mainly includes: modifying CPU- or compiler-related include files: cc.h, cpu.h, perf.h, correctly setting data length, word high and low bit order, etc.; modifying sys__arch.h and sys__arch.h. The C# code contains operating system-related parts. The LW1P protocol stack uses six external functions (libarch.c), which are dependent on the user's system or compiler and therefore need to be implemented manually. The /src/netif/ethernetif.c file is the network driver template, which we can refer to to implement the selected network device driver. After completing the above porting and modification work, we can create a task in uC/OS-II to initialize LW1P and create TCP, UDP, and HTTP tasks. The pseudocode is as follows: Create LWIP task { ■System initialization; ■Memory initialization; ■Packet memory initialization; ■Packet buffer initialization;; ■Network initialization; ■Create a system semaphore; ■Tcpip initialization; ■Wait for system semaphore; Release system semaphore; ■Set gateway; ■Set IP address; ■Set subnet mask; TCP initialization task; HTTP initialization task; UDP initialization task; while (1) {Delay;} } Embedded WEB server With the rapid development of Web technology, Browser/Server (B/S) mode has become a popular development mode. This method basically does not require the development of client programs. Only the server-side program needs to be developed. The client uses a browser such as IE to browse the data on the server. Functionally, the WEB server listens for service requests from the user and provides corresponding services according to the type of user request. The user uses a WEB browser to communicate with the WEB server. After receiving the user's request, the WEB server processes the user request and returns the required data. This data usually appears in the user's browser in a fixed format, containing text or images. HTTP (Hypertext Transfer Protocol) is the core protocol of the WWW (World Wide Web). The WWW uses the HTTP protocol and hypermedia technology to connect various types of information scattered around the world through URLs (Uniform Resource Locators) for user browsing. HTTP is an application-layer, object-oriented protocol. The HTTP protocol has two main functions: transferring files and implementing dynamic interactive applications. LWIP includes HTTP/1.0 in its source code. A simple HTTP/1.0 server running LWIP can respond to at least 10 page requests simultaneously, with a RAM usage of no more than 4KB. To reduce the negative impact of context switching on overall performance, all LWIP protocols are implemented separately from the operating system kernel within a single process. The HTTP program can be a standalone process or reside within a TCP/IP process. If HTTP is a standalone process, it can communicate with the TCP/IP process through the operating system's mailboxes, message queues, etc.; if HTTP resides within the TCP/IP process, the application-layer program communicates with the TCP/IP protocol stack using internal callback functions (Raw API). Due to the limited resources of embedded systems, remote monitoring systems for industrial washing machines based on embedded web require efficient data transmission, a graphical human-machine interface for monitoring, and automatic refresh capabilities. Simultaneously, the analysis and processing of measurement data necessitates local storage of the acquired data. Therefore, a combined browser/server (B/S) and client/server (C/S) architecture is adopted. On the server side, CGI (Common Gateway Interface) technology is used to enable interaction between the browser and the server. CGI defines the interface protocol standard for web servers to call other executable programs, providing a channel for web servers to execute external programs. This technology enables interactivity between the browser and the server. Java Applet technology is used to enhance the browser's functionality, enabling real-time browsing of dynamic data. By accessing web page data on the web server via the B/S method, when the client's IE browser browses this web page, the Java applet source code identified on the web page is downloaded and executed on the client. Within the Java applet source code, a socket is created to complete communication with the server (provided a corresponding server listener is running simultaneously on the web server), acquiring real-time data for display in the browser. In fact, socket communication in Java applets is a typical client/server access method. The system uses Java applets to balance the load between the server and the browser, offloading some tasks previously done on the server to the browser, thus reducing the server's workload. Control System Software Design Users transmit commands over the network to control the washing machine. Washing and spin-drying are completed according to user-set parameters such as water level and temperature. The washing machine needs to automatically detect the quality of the laundry, cotton content, degree of soiling, and soiling type, and use intelligent reasoning to derive the optimal washing plan and automatically complete the washing process. Therefore, the control system software design includes the following tasks: analog signal acquisition, digital signal detection, alarm, valve control, turbidity detection, washing control, motor control, and network tasks. Different priorities are set for each task based on their importance, and tasks communicate with each other via semaphores or mailboxes. Conclusion Embedded web technology is an emerging technology that adopts a thin server model, greatly reducing construction costs. This paper uses an ARM+RTOS+LWIP+HTTP architecture to implement remote monitoring of industrial washing machines, greatly facilitating after-sales service for washing machine manufacturers and management of laundry rooms and factories. The washing machine system software can be remotely upgraded via the network, further improving and enhancing the system's performance.