Design and Architectures for Embedded Systems Prof. Dr. J. Henkel - PowerPoint PPT Presentation

ESII: Spec & Modeling PARTII 1 Design and Architectures for Embedded Systems Prof. Dr. J. Henkel Prof. Dr. J. Henkel CES CES - - Chair for Embedded Systems Chair for Embedded Systems University of Karlsruhe, Germany University of Karlsruhe, Germany University of Karlsruhe, Germany University of Karlsruhe, Germany Today: Specification and Modeling PART II Today: Specification and Modeling PART II - Model and system properties Model and system properties - - http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 2 Where are we ? - models of computation System specification -Spec languages Design space exploration Optimization -low power refine -low power -Performance -performance -Area -Area, … - … Estimation&Simulation -low power -low power System System -performance partitioning -Area, … embedded IP: Emb. Software Middleware, Embedded Hardware -PEs Optimization for: RTOS Processor Design -Memories -low power -Scheduling Design - synthesis -Communication -Performance - extens. Instruction -Peripherals -Area, … - Parameterization - … - … IC technology Integration Prototyping Tape out http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 3 Outline � Motivation � System and Model Properties � Rugby Meta Model � Case Study: A Design Project � Case Study: A Design Project (src: A. Jantsch) (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 4 What are models for? � => => perform various tasks of a design process: perform various tasks of a design process: � Performance modeling � Functional modeling and specification � Design and synthesis � Validation and verification � Validation and verification � Test vector generation � Test coverage analysis � Architecture evaluation and mapping � Technology mapping � Placement and routing (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 5 What is a model? � Model: A model is a simplification of another entity, which can be a physical thing or another model. The model contains exactly those characteristics and properties of the modeled entity which are relevant for a given task. A model is minimal with respect to a task, if it does not contain any other characteristics than those relevant for the task. other characteristics than those relevant for the task. � A model relates to an entity � A model is a simplification of that entity � A model is related to a task and an objective � A model may relate to a not yet existing entity (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 6 Property of models � Inherent property: The property is inherent in every model. E.g. the finite state space of a finite state machine model. � Static property: The property can be statically evaluated. E.g. the required memory of a finite state machine model. � Dynamic property: The property can only be dynamically � Dynamic property: The property can only be dynamically evaluated. E.g. the required memory of a C program. (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 7 Need for heterogeneous modeling � A system consists of different parts. E.g. data flow and control flow dominated parts. � Different objectives apply for different parts. E.g. the system and its environment. � Different parts are developed by different people and tools. � Different parts are developed by different people and tools. E.g. HW and SW. (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 8 So, what is a system? Some definitions: � “an aggregation or assemblage of things so combined by nature or man as to form an integral or complex whole” [Encyclopedia America] � “a regularly interacting or independent group of items “a regularly interacting or independent group of items forming a unified whole” [Webster’s Dictionary] � “a combination of components that act together to perform a function not possible with any of the individual parts” [IEEE Standard Dictionary of Electrical and Electronic Terms] (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 9 Input-Output modeling process (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 10 Mathematical models of real systems (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 11 Example: temperature controller (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 12 Static and dynamic systems � Definition: A static system is one where the output y(t) is independent of past values of the input u(t0), t0 < t for all t � Definition: A dynamic system is one where the output y(t) depends on the current input value u(t) and on at least another input value u(t0) with t0 < t, y(t) = f(u(t), u(t0)). (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 13 Time-varying and time-invariant systems (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 14 Example: time-invariant system (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 15 The concept of state (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 16 State space (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 17 State space model for continuous time, continuous state systems (i.e. differential equation; g - state function) (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 18 State space model for discrete time systems (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 19 State space model time-invariant discrete time (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 20 Linear and non-linear systems (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 21 Deterministic, stochastic and non-deterministic systems � Definition: A system model is deterministic if the output function f and the state function g are functions in the sense that they evaluate a given argument always and unambiguously to the same result. result. A system model is stochastic if at least one of their output variables is a random variable. A system model is nondeterministic if a given input may result in different outputs. (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 22 Events � Events are associated with a time instance and have no duration. � Arrival of a message; � Change of a signal value; Change of a signal value; � Change of a state; � A counter exceeding a given threshold value; � An elapsed time period; � etc. (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 23 Time-driven and event-driven systems � In time-driven systems the advance of time causes the system to become active. � In event-driven systems the occurrence of an event causes the system to become an event causes the system to become active. (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 24 Systems classification summary (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 25 The Rugby Meta-Model � Abstraction in four domains � Computation � Communication � Time � Data (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 26 Example of a hierarchy (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 27 Example of an abstraction (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 28 Ways to handle complexity (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 29 Hierarchy, Abstraction, Domain (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 30 Rugby (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708

ESII: Spec & Modeling PARTII 31 Domains in Rugby (src: A. Jantsch) http://ces.univ-karlsruhe.de J. Henkel, Univ. of Karlsruhe, WS0708