Design of information appliance control system based on XML

introduction

Information appliances are a new generation of home electronic products that are the result of the combination of information technology and traditional consumer appliance technology. Information appliances are home appliances that use computers as a platform and integrate sound, light, and images. They are neither computers nor traditional home appliances, but new home appliances that integrate certain computer functions, audio-visual functions, communication functions, and Internet access functions. Information appliances are essentially computerized home appliances, and are new products developed to meet the various needs of people's daily lives (such as entertainment, education, communication, Internet access, financial management, etc.).

How to realize interoperability and plug-and-play of information appliances has become the main research direction of information appliances.

1 Information Appliance Control Structure

There are three ways to control information appliances: centralized control, remote control, and universal remote control. Centralized control uses the computer at home as the control center. The operating status information of all appliances can be viewed on the computer, and information appliances can be controlled through graphical operations as needed. Remote control means that when you are working outside or on the way home, you can view the operating status information of home appliances through the office computer or PDA device, and you can also perform the desired operations on the appliances. Universal remote control controls information appliances through a specially designed universal remote control.

Regardless of the method used to control information appliances, the interface of information appliances must be defined first. The so-called interface mainly includes the state attributes and operation functions of information appliances. Secondly, the control command package must be defined. Various control methods form control command packages according to the operations to be performed and send them to the home network. Each appliance monitors its own port and parses and executes the control command package once it receives it. This article uses XML as the description language of information appliance interfaces and control commands, and provides a solution for information appliance control based on XML. As shown in Figure 1.

Information home appliance manufacturers must provide information that the interface definition file described in XML must be embedded in the information home appliance. When the user connects the information home appliance to the home network, the information home appliance will actively register the interface definition file in the centralized control device (gateway) and store it in the embedded database. The centralized control can generate control commands based on the interface definition to control each registered information home appliance.

Universal remote control and remote control are the same in principle, but the communication methods are different. Universal remote control generally communicates with centralized control via wireless, while remote control generally communicates with centralized control via the Internet.

Both of them first obtain the interface definition of the information appliance from the centralized control, and the built-in control command generator generates the control command and sends it to the centralized control, which is then forwarded to the information appliance. Finally, the built-in control command interpreter of the information appliance interprets and executes the control command.

2 Definition of Information Appliance Interface

The home appliance device interface is simply defined through XML, with the head node IA, and the IA node includes 4 child nodes, which represent the device name, device attributes, device status, and device operation set. These 4 nodes are fixed, but the nodes under these nodes will vary depending on the home appliance device and the home appliance manufacturer. For example:

IAName indicates the device name, and Attribution indicates the device attribute set, such as manufacturer, warranty date, etc. Status indicates the status of the device, such as power switch, temperature, humidity, wind speed, whether to sweep the air, etc. The control device can obtain the status information of the device through the content of these nodes. Operation indicates the operations that the device can perform, such as whether the air conditioner can increase or decrease the temperature, humidity, wind speed, switch the power, etc.

The interface definition file is provided by the manufacturer, and centralized control only needs to register it. Of course, the manufacturer can expand the interface definition of its information home appliance products according to the needs of development to meet the needs of safety and other aspects.

3 Control command definition

In order to describe the control command information and enable parsing and execution, we define a standard control command package through XML. When the control center or remote control operates a home appliance, a control command package in the following format is generated:

The root node is Command, and under it are 5 nodes: TolP, FmmIP, Time, OperationName, and OperationValue. TolP indicates which device the command is to be sent to, FmmIPI/IJ indicates who issued the command, Time is the time when the command is issued, and the following two nodes are the name of the operation to be performed and the operation parameters. In this example, the temperature of the device with IP 192.168.0.125 is increased by 2 degrees. The design here is just a simulation of basic functions. Due to the good extensibility of XML, the control command package can be expanded.

4 Centralized Control

In the centralized control mode, the control center stores the interface definition of registered information appliances, so that it can update the device status information through polling, or actively notify the control center when the device status changes. In the control center, users can view the information of all current devices and control the devices through graphical operations. At this time, the control center calls the command generator to package the user's operations into an XML format control data packet and send it to the home LAN. The information appliances connected to the home LAN will be able to receive the control command packet at its control packet receiving end. At this time, only the operated home appliance will call the built-in command parser to parse the control data packet and execute it, thus completing the control of the home appliance.

5 Remote control

In remote control mode, home appliances can be controlled by remote controllers. At present, different home appliances have different remote controllers, which are incompatible with each other. Now imagine a remote controller that can control all devices. This remote controller has a certain storage function, which stores the device interface files of the controlled devices. When controlling, the device to be controlled and the operation to be performed are selected through the menu. The built-in command generator of the remote controller will generate a command packet based on the selection and send it to the control center through the wireless network.

6 Remote Control

When you are at work or on your way home, if you want to control the information appliances at home, you need remote control. You can use a PC or PDA to view the status of home appliances and control their operation. How to achieve remote control? Generally, it can be achieved through the interconnection and communication between the client and the home gateway. You can also publish various operations and information viewing of home appliances as a service, introduce the concept of WebJlt service, and then add restrictions on submitting certificates to the objects of the request, so that only users with legal certificates can operate their home appliances, and can also be expanded to meet other more detailed requirements. Currently, WebHt service technology is being deeply studied and widely used. Compared with traditional Socket communication, the flexibility and loose coupling brought by WebBt service make remote control calls more convenient, flexible and extensible.

7 Conclusion

The purpose of the design is to propose a way to realize smart home and simulate it to deeply understand its feasibility, advantages and disadvantages. The key lies in the definition of device interface, the definition of control command, and the analysis and operation based on these definitions.