Research And Design Of Application Upgrade Mechanism Based On Embeded Linux

With the development of technology and the introduction of new technology, embeded system has been widely used in life, and the embeded products had played an important role in people’s daily life. Embeded Linux system has been widely applied to many fields such as medical electronics, information appliances, remote communication, STB and so on. The source code of embeded linux system is open, many linux lovers become powerful technical supporters. Linux is a free operation system, and has attractive features including smaller kernel, high efficiency and can be cut. Embeded linux is a system that modified on the basis of ordinary linux, which can work on the embeded system stable and efficiently. Embeded linux surpport many kinds of CPU, that make embeded products easy to use and develop. The topic in this thesis is focused on digital TV set-top box which is developed on embeded linux, a typical application of embeded system.With the development of digital television, digital television industry is developing. Every country, accrording to their own conditions, has developed the transfer plan from analogue television to digital television. The key to the development of digital TV is how to provide users with richer digital TV applications through the teminal equipment, this demands continuously upgrade of STB software system to meet the growning market demand.To design a complete application upgrade system of set-top box which is based on embeded linux is the main content of this thesis, including the production of upgrade data stream and the design and implemention of a terminal Loader system.In the begainning of this article, we firstly introduced the System Software Upgrade agreement which is developed by DVB system, and studied the ways to carry the upgrade data——Data Caroul and achieve it. On this basis, combined with the features of linux designed a upgrade data production proposal of front-end and achive it. Including the struct design of upgrade data, the package of upgrade data and the PSI/SI signalling. Next, on the basis of the package solution, combined with the features of STB hardware platform, we design and implement each module of the Loader system, including search module, filter module, download module and memory control module.Finally, the application upgrading system is tested. The test results show that the function of the application upgrade system is perfect. The Loader system can locate the upgrade fata stream quickly and accurately and can detect a variety of upgrade error. The system has a good performance.