Componentbasedembeddedsystems.pptVIP

Chapter 16 - Component based embedded systems Chapter 16Component based embedded systems Overview Introduction Component technology in embedded systems Case study – ABB’s Field Devices Prerequisites for effective development of Component-based embedded systems Summary Where is the problem? Huge market arises for embedded devices, and thus for software for them Similar basic functionalities are repeated New functionalities are added constantly Shorter development time is required Introduction Embedded vs. Component-based Monolithic approach requires re-implementing the functionalities Component based SE provides a mean to reuse the functionalities Component technology in embedded world Contractually specified interfaces Component as a unit of composition and independent deployment Explicit context dependencies Component granularity Reuse Location transparency Component wiring Portability, platform independence Contractually specified interfaces State-of-the-art technologies approach: Interfaces as pure collection of methods. Interfaces II Component interfaces support: Late binding, Polymorphism, Semantic specification Pre conditions, Post conditions, Invariants Unit of composition and independent deployment Run-time composition Component model, Run-time environment, Dynamic communication, Design-time composition Capable of generating monolithic firmware from component-based design, Optimization Explicit context dependencies What is a context in embedded world? Other components and interfaces Run-time environment CPU, RTOS, Component implementation language, Resource constraints Component granularity Coarse-grained components, Too heavy bag of unnecessary functionality, Too much resources used, Fine-grained components, Light, unneeded functionality reduced, Scarcer uses of resources, Greater communication overhead, Reuse Black-box reuse From component’s user point of view, White-box reuse From composition environment point of view Gray-box reuse (composition