Computing For Embedded System IEEE Instrumentation and Measurement Technology Conference Budapest, Hungary, May 21-23, 2001. Author ： Edward A. Lee UC

Computing For Computing For Embedded SystemEmbedded System

IEEE Instrumentation and MeasurementIEEE Instrumentation and MeasurementTechnology ConferenceTechnology Conference

Budapest, Hungary, May 21-23, 2001.Budapest, Hungary, May 21-23, 2001.

AuthorAuthor ：： Edward A. LeeEdward A. LeeUC Berkeley, Berkeley, CA 94720, USA UC Berkeley, Berkeley, CA 94720, USA

IDID ：： E9406010E9406010 InterpreterInterpreter ：： YU - HAU LIOUYU - HAU LIOU

Department of Department of Computer Science and Information EngineeringComputer Science and Information Engineering

Da-Yeh UniversityDa-Yeh University

Outline Embedded SystemOutline Embedded System

A general definition of embedded systems is: computing systems with tightly coupled hardware and software integration, that are designed to perform a dedicated function.


Embedded System needs the Embedded System needs the minimum code .minimum code .

Embedded System must have task Embedded System must have task

priority with scheduling threadpriority with scheduling thread

highly.highly. Embedded System needs the highestEmbedded System needs the highest

reliability .reliability .


Embedded System is different from Embedded System is different from general-purposegeneral-purpose processor processor considerably .considerably .

Computing For Embedded SystemComputing For Embedded System

Framework enforces the patterns and implements the models of computation .

Frameworks can be built to support useful architectural patterns .

The design pattern rather than as a language feature.


The framework is a set of constraints onThe framework is a set of constraints on

components and their interaction, and a components and their interaction, and a set of benefits that derive from those set of benefits that derive from those constraints.constraints.


We really want are architecture design languages rather than architecture description languages.

That is, their focus should not be on describing current practice, but rather on improving future practice.


VHDLVHDL ( V ( Very High Speed Integrated ery High Speed Integrated Circuit Circuit HHardware ardware DDescription ) escription ) LLanguage anguage

JAVAJAVA SYSTEM CSYSTEM C


State Machine

1. In finite state machines (FSMs) FSM models are amenable to in-depth formal analysis, using for

example model checking, and thus can be used to avoid surprising

behavior. Moreover, FSMs are easily mapped to either hardware or

software implementations.

2. 2. Abstract state machines (ASMs)


Models of computation 1. Synchronous/reactive models The components represent relations between input and output values at each tick, and are usually partial functions with certain technical restrictions to ensure determinacy.

2. Discrete-event models The components process events in chronological order, so is popular for specifying hardware and simulating telecommunications systems .

3. Cycle-driven models Cycle driven models associate components with clocks and stimulate computations regularly according to the clock ticks .

Are patterns suitable for Are patterns suitable for Embedded System ?Embedded System ?

Performance

Time Cost

What does this illustration meanWhat does this illustration mean ？？

─ ─ Implementation is momentous .Implementation is momentous .


CPSR ( CPSR ( http://http://www.cpsr.orgwww.cpsr.org/about//about/))　　 We now have 330 patterns (many nearly compl

ete and many still "placeholders" -- alas!) in the "Pattern Pool". There are more than 115 patterns in use .


Technical report

Dr.Michel J. Pont

http://www.le.ac.uk/eg/mjp9/ “Can patterns increase the reliability of embedded

hardware- software co-designs?”, IEE Colloquium on Hardware-Software Co-Design, Savoy Place, London, 8 December, 2000. IEE Colloquium Digests #111.

FinalFinal

We believe that the best way to learn deWe believe that the best way to learn design patterns is to be coached by by somsign patterns is to be coached by by someone who has used them while your teaeone who has used them while your team works on a real project. In this way, wm works on a real project. In this way, when they will be useful, your coach can shen they will be useful, your coach can see that, and help your team use them. ee that, and help your team use them.

FromFrom ：： http://www.netobjectives.com/design.htm

Documents

Computing For Embedded System IEEE Instrumentation and Measurement Technology Conference Budapest, Hungary, May 21-23, 2001. Author ： Edward A. Lee UC