| The design of real-time system not only needs to ensure the reliability but also to ensure the accuracy of time.Time predictability is one of the important research directions to solve the system time accuracy.At present,traditional models such as threads model lack the timing predictability.Servant/Exe-flow model is a service-oriented model.The functional attributes in the SEFM are composed of a set of services.Services interact explicitly and avoid the problem that threads model lacks predictability because of the synchronization and competition.On the other hand,the system from modeling to implementation is related to the control engineer and the software engineer,and the traditional realization process is easy to lose the original syntax-semantics of the model.The model-driven development framework relies on its rigorous development process and modeling platform to maximize the semantic integrity of the model syntax in the process of system implementation.In this dissertation,the research focuses on embedded real-time system design and realization based on model driven method.The main work is as follows:(1)Designing TSEFM(Timed SEFM)model with time predictable attributes.Based on the original SEFM,the semantics of model time is added,and the concept of service is simplified,which makes the abstraction of TSEFM more suitable for embedded system design.Combined with the semantics of model time,the formal definition of the TSEFM is proposed.The new model is analyzed by time predictability and schedulability,which shows the feasibility and correctness of the model.(2)Implementing a model-driven development framework with time predictable attributes.By introducing the abstract syntax and concrete syntax of TSEFM,the core technology of model-driven development framework is realized.Combining the programming meta-template technology and compiling technology,the code generator mechanism of TSEFM is discussed.The realization of the model about the physical time and model time synchronization,memory management and scheduling in the model is proposed.(3)Proposing the system design flow framework based on TSEFM.Combined with the model-driven system design and implementation process,the system design flow framework based on TSEFM is proposed.The experiment of the following control system is designed,and the feasibility of the model and the feasibility of the system design process are analyzed and proved from the experimental results.In the dissertation,the design of TSEFM is described in detail,and the development framework based on TSEFM is realized.Finally,the correctness of new model and the feasibility of the design process framework are proved by the following vehicle control system experiment. |
