The Researches Of The Methods Of Embedded Software Development

With the rapid growth of the applications of embedded system,the traditional development method of embedded system is no longer suitable for the growing requirement of product design from the market.More and more people put much emphasis on the development method of embedded system to improve its efficiency and quality for the embedded software development.Using the component software development technology,based on the practical requirement of the embedded software development,this paper focuses on the research of the development method of embedded software,and then gives out an example which develops the application of Pocket-Opening Machine.First,the paper tries to use the component software development technology in the field of embedded system.After making the research of the characteristics of the embedded system and analyzing the current situation of the component software development technology of the embedded software,the paper extends the concept of the common software component and gives out a component model for the embedded system.And then,the paper designs a six-layer architecture.It not only makes the separation of software and hardware,but also the separation of functionality.Based on such component models and architecture,the paper designs a visible development environment.it can make the configuration,management,self joint and self source code generation of component.It greatly makes it simple for the management of the components.Second,the paper details the componented process of embedded system and gives out its flow—define the component object,analyze the composition of component system,define the component granularity,design the component and implement the component system,establish the component library and then make the maintenance of the system.Meanwhile,the paper makes the component for the common I/O embedded modules which verifies the feasibility of the embedded component models and architecture.Third,the paper makes research on programming design technology and method based on RTOS.Based on the application of the RTOS kernel,the paper researches the characteristics of task and the method of task separation.It points out that task separation is the premise of the application programming which based on RTOS.The software modules based on RTOS exists as the forms of tasks.The method discussed above has been verified validly during the application programming development of the Pocket-Opening machine.Last but not least,the paper analyzes the schedulability of the tasks based on EDF.Real-time task scheduling theory is the core and key of the real-time process technology.It makes it possible for the theoretical predictability of scheduling algorithm's schedulability.Based on the analysis of EDF schedulability algorithm,the paper establishes a sporadic model and breaks the limitation of the periodicity task.A more general necessary and sufficient condition for schedulabilityis proposed—an algorithm based on the task maximum demand.Through the theoretical verification, this algorithm is proved to be feasible.The improved algorithm provides the basis for implementation of the EDF in the practical application.The embedded controller has been completed on the whole and it's validated in the lab.The research work of this paper,including application and method research of embedded system,provides a helpful guidance to the embedded system development in othe application fields.