1. 10 nov 1999SEESCOA Applicability of UML/RT to Embedded Systems Programming Technology Lab (PROG) System & Software Engineering Lab (SSEL) Dept. of Computer Sciences (DINF) Vrije Universiteit Brussel (VUB) Werner Van Belle (WVB) Tom Toutenel (TT)

2. 2 10 nov 1999SEESCOA Design Issues Concurrency Timing Constraints Hardware Constraints memory constraints input/output are different OS Constraints event handling interface diversification (RTOS, minikernels) Correctness

3. 3 10 nov 1999SEESCOA Real-Time UML Developed by ObjecTime & Rational Rose Douglass, Bruce Powel. Real-Time UML: Developing Efficient Objects for Embedded Systems. Addison Wesley 1998. A language for expressing the constructs and relationships of complex real-time systems.

4. 4 10 nov 1999SEESCOA The UML Meta-Model Feature visibility:{public, protected, private} * Composition association Generalization association Class isActive:Boolean Classifier (Meta)class GeneralizeableElement isRoot:Boolean

5. 5 10 nov 1999SEESCOA Concurrency in UML/RT Actors already are concurrent in UML Interaction Primitives: asynchronous balking call waiting timed

6. 6 10 nov 1999SEESCOA Concurrency in UML/RT (2) message queues, rendezvous, RPC guards, transactions only rudimentary support

7. 7 10 nov 1999SEESCOA Real-Time Constraints UML: no timing information UML/RT: possibility to add timing constraints sequence diagram with timing annotations timing diagram

8. 8 10 nov 1999SEESCOA Sequence Diagram call ack time number call ack talk transfer CallerOperatorCallee a b { b - a < 1 s }

9. 9 10 nov 1999SEESCOA Timing Diagram time Connected Not Connected Establishing deadline

10. 10 10 nov 1999SEESCOA Hardware Memory Constraints (Resource Constraints): no specific support in UML/RT Input/Output Variations: annotated with ports and signal lines in UML/RT OS Interfacing & Event Handling huge impact on design, but very hardware dependent

11. 11 10 nov 1999SEESCOA Seamlessness Design to Implementation correctness robustness (cfr exceptions) Impact Analysis problem is even more prominent for embedded systems

12. 12 10 nov 1999SEESCOA Problems Bare-To-The-Metal Coding Not Portable Abstraction Layers More Resource Consumption Conflict of Interests

13. 13 10 nov 1999SEESCOA Solution Abstraction at the design level: reuse/evolution should be easy (cfr variation points) patterns based upon implemented architectures never too implementation oriented should be compilable

14. 14 10 nov 1999SEESCOA Conclusion Instead of making hardware-specific abstractions, we envision tools with ready-made compilable architectures.