The Research Of Bottom Layer Middleware In New Type Integrated Services Terminal

The Integrated Services Terminal(IST) that researched in this topic is based on the new HFC network. The new HFC network has been improved the transmission mechanism and technology of the existing HFC network, caused the available bandwidth of user to be wide, provided the genuine broad band multimedia interactive services, satisfied the demand of each kind of comprehensive services, moreover fallen the expense of the network equipment and the subscriber's equipment. The equipment of IST can provide digital television services, internet services and IP telephone services which are universal requirement of subscriber.The middleware which exists as the application program interface API is software, located between the real-time operating system and the applications in IST. The entire APIs are saved in FLASH. The appearance of middleware causes each kind of applications no longer to rely on the different hardware platform, which is the pivotal technology of developing the increment services for digital TV. This paper puts emphasis on researching the bottom layer middleware, namely the core system module and the Java virtual machine.Firstly, by analyzing the requirement of the family integrated services terminal(IST), and linking the characteristic of middleware shielding the bottom difference, in order to shield the priority difference of operating system, real-time management module was added in the core system module, which guaranteed the real time of middleware with soft real-time. Based on the layered architecture of real-time middleware, the real-time management module and the adaptation layer were researched mainly.The real-time management module is the key of the real-time middleware. The processing data flow of real-time management module and FP module based on the queue simulation method were designed in this thesis. According to analyzing the factors of affecting the data processing, and referring to the literatures, the validity and the rationality of FP module were confirmed. And the codes of processing flow were edited.The realization of adaptation layer is a pivotal technology in middleware development. Whether its solution perfect or not will affect directly the middleware system can or can't seamless transplant to each kind of different hardware platforms, and have the important theory and the practical significance to the middleware technology development. A complete adaptation solution was recommended through researching a kind of open source middleware OpenMHP in this thesis. The resource management module and the resource management interfaces were carried out basing on the DAVIC resource management mechanism. Eventually, OpenMHP was transplanted to the embedded linux environment.For understanding between the real-time management module and the operating system, algorithms of priority mapping and preventing the priority turning over were introduced, which have guaranteed the right mapping form the middleware priorities to the operating system priorities.Java virtual machine which provides the explanation execution environment for Java language is also the important module of bottom middleware. In this thesis, linux CVM which SUN corporation provides was transplanted under the ARM9 experimental environment, and debugged in the S3c2410 hardware platform. So it can guarantee the applications which developed with the Java language can run successfully in the IST.This thesis puts emphasis on researching the bottom layer middleware, including the design of real-time management module, the realization of resource management module in adaptation layer and the transplantation of Java virtual machine.