EES01-Embeded Sys. Introduction

7/29/2019 EES01-Embeded Sys. Introduction

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Embedded Electronic Systems

G

raphics:

AlexandraNolte,GesineMarwedel,2003

Davide BrunelliDISI University of Trento

AA 2010-2011 P.Marwedel


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Motivation for Course (1)

According to forecasts characterizedby terms such as

Disappearing computer,

Ubiquitous computing,

Pervasive computing,

Ambient intelligence,

Post-PC era,

Cyber-physical systems.Basic technologies:

Embedded Systems

Communication technologies

P.Marwedel


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Universitt DortmundUniversitt DortmundUniversitt Dortmund

Motivation for Course (2)

Information technology (IT) is on the verge of anotherrevolution. Driven by the increasing capabilities and ever declining costsof computing and communications devices, IT is being embedded into agrowing range of physical devices linked together through networks andwill become ever more pervasive as the component technologies become

smaller, faster, and cheaper... These networked systems of embeddedcomputers ... have the potential to change radically the way people interactwith their environment by linking together a range of devices and sensorsthat will allow information to be collected, shared, and processed in

unprecedented ways. ... The use of [these embedded computers]

throughout society could well dwarf previous milestones in theinformation revolution.

National Research Council Report (US)Embedded Everywhere

Source. Ed Lee, UC Berkeley,ARTEMIS Embedded SystemsConference, Graz, 5/2006]

P.Marwedel


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Growing importance of embedded systems (1)

Spending on GPS units exceeded $100 mln during Thanksgivingweek, up 237% from 2006 More people bought GPS units thanbought PCs, NPD found. [www.itfacts.biz, Dec. 6th, 2007]

, the market forremote home health monitoringis expected to

generate $225mln revenue in 2011, up from less than $70mln in2006, according to Parks Associates. . [www.itfacts.biz, Sep. 4th, 2007]

According to IDC the identity and access management(IAM) marketin Australia and New Zealand (ANZ) is expected to increase at a

compound annual growth rate (CAGR) of13.1% to reach $189.3 mln

by 2012 [www.itfacts.biz, July 26th, 2008].

Accessing the Internet via a mobile device up by82% in the US, by49% in Europe, from May 2007 to May 2008 [www.itfacts.biz, July29th, 2008]

P.Marwedel


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Growing importance of embedded systems (2)

.. but embedded chips form the backbone of theelectronics driven world in which we live ... they arepart of almost everything that runs on electricity[Mary Ryan, EEDesign, 1995]

The future is embedded, Embedded is the future!

Foundation for the post PC era

ES hardly discussed in other CS coursesES important for Technical University

ES important for Europe

Scope: sets context for specialized courses

1.3 importance

Importanceof

education

P.Marwedel


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Where are the CPUs?

Estimated 98% of 8 Billion CPUs produced in 2000 used for embedded apps

Where Has CS Focused?

InteractiveComputers

Servers,etc.

200Mper Year

In Vehicles

Embedded

In Robots

Where Are the Processors?

Look for the CPUsthe Opportunities Will Follow!

8.5B Partsper Year

Robots6% Vehicles12%

Direct2%

Source: DARPA/Intel (Tennenhouse)

Copyright 2003 Mani Srivastava


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History of Computing

1960

1970

1980

1990

1995

19982000

Mainframe

Mini

Workstation

PCRouters

Cell phones, PDAs

Networked Embedded

Systems?

IBM

DEC

Sun, HP

Intel, DellCisco

Nokia, Palm

???

Increasing # of computers / personIncreasing connectivity

Technology discontinuities drive new computing paradigms and applications


U i ittD t dU i ittD t dU i ittD t d


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Embedded systems

and ubiquitous computing

Ubiquitous computing: Information anytime, anywhere.Embedded systems provide fundamental technology.

CommunicationTechnology

Optical networkingNetwork management

Distributed applicationsService provision

UMTS, DECT, Hiperlan, ATM

European Commission

EmbeddedSystems

RobotsControl systemsFeature extractionand recognitionSensors/actorsA/D-converters

Pervasive/Ubiquitous computingDistributed systems

Embedded web systems

Real-time

Dependability

Qualityof

service

P.Marwedel



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Welcome to EES

Logistic



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Structure of this course

Design Tools

AlgorithmsInfrastructureDesign flows

Architectures

Low-costLow-power

ctrlMSP430

EnergyEfficientMultimedia

proc.ARM-Cortex

UniversittDortmundUniversittDortmundUniversittDortmund


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Course Program (1)

MICROCONTROLLER-BASED SYSTEMS- Levels of abstraction in modern microprocessors- Microprocessor-based system architecture- CPU microarchitecture- I/O devices and techniques- Parallel/serial interfaces

- Asynchronous and synchronous communication- Timers- PWM and watchdog- CAN bus and AMBA bus

MICROPROCESSOR-BASED SYSTEMS

- Architecture- Pipelining

SENSORS- Definition of sensor; classification criteria- Active and passive sensors



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Course Program (2)

INFORMATION MANAGEMENT SYSTEMS (IMS)

Functional block diagram of a communication system; i/o relationshipIMS evolution- wireless sensor networks: organization and characteristics- node architecture

Functional units of a IMS:- sensor: definition, classification criteria, examples

- conditioning: definition, examples- information extraction: definition, examples- analog and digital signal processing: basic components

Analog section: characteristics and performanceA/D section:

- performed functions

- basic components- sampling-and-hold amplifier- quantizationDigital section:- characteristics and performance- definition of on-line and off-line processing- definition of real-time processing (both sequential and block)



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Course Logistics: Instructor Info

Email: [email protected]: +39 0461 28 5221

Office hours: by appointment Im very responsive by email

Please put [EES course] in mail subject line



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Exam

1-hour written examination.There will be two questions:a- general questionb- practical question(e.g. MCU configuration, experience in lab, )

each contributing up to 15 points to the total score.

You can consult your notes and datasheet

The exam is passed if the evaluation of the written test is

at least 18/30.

Final mark can be integrated with a short oral testThe oral test will contribute to the total score with up to amaximum of 3 points,



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Alternative Exam

(strongly encouraged)

Implementation Project work Groups of 1-2 students A set of possible project proposals will be available in the last part of the course.

If you have proposal, come and discuss possible project ideas with me!

Project work completion is not mandatory. The project will be evaluated mainly forthe diligence and the effort of the students

Up to 15 minute power point interactive presentation (slide in English)

like a conference talk with a demo

Up to 12 page report in the style of a technical conference paper (Italian or English)(e.g. IEEE style

www.ieee.org/web/publications/pubservices/confpub/AuthorTools/conferenceTemplates.html )



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Experimenters Board Integrated 12-bit ADC & DAC, Op-

Amps, DMA, Multiplier, LCD Controller

Board: mic, buzzer, LCD,touch-pad, buttons, proto space, RS232,JTAG, 3.5mm audio jack

Chipcon expansion: CCxxx0EMK EVMinteface

Interfaces:SPI, UART, I2C, IrDA

MSP-EXP430FG4618

Tools for Labs & Projects



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Kit includes:2 x eZ430-RF2500T target boards1 x eZ430-RF USB emulator

1 x AAA battery packIAR Kickstart Development ToolWireless Sensor Monitor DemoSimpliciTI preloaded

Documentation and source code

CC2500 Radio

MSP430F2274 MCU

eZ430-RF2500




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WSN, Body Sensors SDK

32 bit RISc architecture (ARC)

Onboard temperature

Light level and humidity sensors

Bitmapped LCD display 128x64

USB connection

Jennic




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Texas Instruments OMAP 3503 ApplicationProcessor with ARM Cortex-A8 CPU600 MHz

256MB RAM 256MB Flash 802.11(g) and Bluetooth

GumStix Overo Air


3.2 Mpixel camera board



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Some Books (for your interest only)

Embedded, Everywhere: A Research Agenda for Networked Systems of Embedded

Computers, National Research Council. http://www.nap.edu/books/0309075688/html/

G.D. Micheli, W. Wolf, R. Ernst, Readings in Hardware/Software Co-Design, Morgan

Kaufman.

S.A. Edwards, Languages for Digital Embedded Systems, Kluwer, 2000.

R. Melhem and R. Graybill, Power Aware Computing, Plenum, 2002.

M. Pedram and J. Rabaey, Power Aware Design Methodologies, Kluwer, 2002.

Hassan Gomaa, "Software Design Methods for Concurrent and Real-Time Systems," Addison-

Wesley, 1993.

P. Lapsley, J. Bier, A. Shoham, and E.A. Lee, DSP Processor Fundamentals: Architecturesand Features, Berkeley Design technology Inc,, 2001.

R. Gupta, "Co-synthesis of Hardware & Software for Embedded Systems," Kluwer, 1995.

Felice Balarin, Massimiliano Chiodo, and Paolo Giusto, "Hardware-Software Co-Design of

Embedded Systems : The Polis Approach," Kluwer, 1997.

P. Marwedel, "Embedded System Design, Kluwer Academic Publishers.

No books required

unfortunately NO single adequate book existsId mention books as we go along



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Embedded Electronic Systems

Scenarios & Examples



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Application areas (1)

Automotive electronics

Avionics

Trains

Telecommunication

1.2 Application areas P.Marwedel



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Medical systemsFor example:

Artificial eye: severalapproaches, e.g.: Camera attached to

glasses; computer worn atbelt; output directly

connected to the brain,pioneering work by WilliamDobelle. Previously at[www.dobelle.com]

Translation into sound; claimingmuch better resolution.[http://www.seeingwithsound.com/etumble.htm]

P.Marwedel



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Authentication

Military applications

http://www.submarine.co.mp/wallpaper/submarine_640.jpg

P.Marwedel



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Consumerelectronics

P.Marwedel



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Smart buildings

Industrial automation

Show movie http://www.date-conference.com/conference/2003/keynotes/index.htm P.Marwedel

http://www.date-conference.com/conference/http://www.date-conference.com/conference/http://www.date-conference.com/conference/http://www.date-conference.com/conference/http://www.date-conference.com/conference/


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Robotics

Pipe-climber RobotJohnnie(Courtesy

and :H.Ulbrich, F.Pfeiffer, TUMnchen)

Show movie of 2-legged robot(s) P.Marwedel



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Application Examples

Some embedded systems fromreal life



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Smart Beer Glass

8-bit processor

Capacitive sensor

for fluid level

Inductive coil for RF

ID activation &

power

CPU and reading coil in the table.Reports the level of fluid in the glass,alerts servers when close to empty

Contact less

transmission

of power and

readings

Jakob Engblom

Integrates several technologies:

Radio transmissions Sensor technology Magnetic inductance for

power Computer used for

calibrationImpossible without the computerMeaningless without the

electronics

P.Marwedel



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Pedometer

Obvious computer work: Count steps

Keep time

Averages

etc.

Hard computer work:

Actually identify when a step is

taken Sensor feels motion of device,

not of user feet

Jakob Engblom

P.Marwedel



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Mobile phones

Multiprocessor

8-bit/32-bit for UI

DSP for signals

32-bit in IR port

32-bit in Bluetooth

8-100 MB of memory

All custom chips

Power consumption & battery lifedepends on software

Jakob Engblom

P.Marwedel



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If you want to play

Lego mindstorms robotics kit

Standard controller

8-bit processor

64 kB of memory

Electronics to interface tomotors and sensors

Good way to learnembedded systems

Jakob Engblom P.Marwedel



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Mobile base station

Massive signal processing

Several processing tasks per connectedmobile phone

Based on DSPs

Standard or custom

100s of processors

Jakob Engblom

P.Marwedel



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Telecom Switch

Rack-based Control cards IO cards

DSP cards ...

Optical & copperconnections

Digital & analog signals

Jakob Engblom

P.Marwedel



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Smart Welding Machine

Electronics control voltage & speed ofwire feed

Adjusts to operator

kHz sample rate 1000s of decisions/second

Perfect weld even for quite clumsyoperators

Easier-to-use product, but no obviouscomputer

Jakob Engblom

P.Marwedel



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Sewing Machine

User interface Embroidery patterns Touch-screen control

Smart Sets pressure of foot depending

on task Raise foot when stopped

New functions added by upgradingthe software

Jakob Engblom

P.Marwedel



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Inside your PC

Custom processors Graphics, sound

32-bit processors

IR, Bluetooth

Network, WLAN

Harddisk

RAID controllers

8-bit processors USB

Keyboard, mouse

Jakob Engblom

P.Marwedel



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Forestry Machines

Jakob Engblom

Networked computersystem

Controlling arms &tools

Navigating the forest Recording the trees

harvested

Crucial to efficient

workTough enough to be outin the woods

P.Marwedel



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Cars

Multiple networks Body, engine, telematics,

media, safety

Multiple processors Up to 100 Networked together

Jakob Engblom

Functions by embeddedprocessing: ABS: Anti-lock braking

systems ESP: Electronic stability

control Airbags Efficient automatic

gearboxes

Theft prevention with smartkeys

Blind-angle alert systems ... etc ...

P.Marwedel



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Automobiles as distributed embedded systems

P.Marwedel



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How many CPUs in a car?

Todays high-end automobile may have more than 100 microprocessors:

4-bit microcontroller checks seat belt;

8-bit for door locks, lights, etc.

16-bit for most functions (e.g. Microcontrollers run dashboard

devices);

16/32-bit microprocessor controls engine, airbags...

DSP for Automatic stability control

16/32-bit microprocessor for Automatic stability control

Intelligent Sensors and actuators distributed all over the vehicle



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Extremely Large

Functions requiring computers: Radar

Weapons

Damage control

Navigation

basically everything

Computers:

Large servers 1000s of processors

Jakob Engblom

P.Marwedel



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Networks and embedded systems

An increasing number of embedded systems connect to theInternet. Resource management. Security.

Many specialized networks have been developed forembedded systems: Automotive. Device control.

P.Marwedel



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Embedded system at glance

Real-Time Operation

Reactive: computations must occur in response to external events

Correctness is partially a function of time

Small Size, Low Weight

Hand- held electronics and Transportation applications -- weight costsmoney

Low Power

Battery power for several hours (laptops often last only 2 hours)

Harsh environment

Heat, vibration, shock, power fluctuations, RF interference, lightning,corrosion

Safety- critical operation Must function correctly and Must notfunction in correctly

Extreme cost sensitivity

$. 05 adds up over 1,000, 000 units

Universitt DortmundUniversitt DortmundUniversitt Dortmund Copyright 2003 Mani Srivastava


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An Embedded Control System Designers View



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Complexity and Heterogeneity

Heterogeneity within H/W & S/W parts as well S/W: control oriented, DSP oriented H/W: ASICs, COTS ICs

controller

control panel

Real-timeOS

controllerprocesses

UIprocesses

ASIC

ProgrammableDSP

ProgrammableDSP

DSPAssembly

Code

DSPAssembly

Code

Dual-portedRAM

CODEC



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Increasingly on the Same Chip

System-on-Chip (SoC)



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Many Types of Programmable Processors

Past

Microprocessor

MicrocontrollerDSP

Graphics

Processor

Now / Future

Network Processor

Sensor ProcessorCryptoprocessor

Game Processor

Wearable ProcessorMobile Processor



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More SoCs

Camera-on-chip (Bell Labs) Solar-power Wireless Sensor (Berkeley)



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SoCs with Mechanics: Berkeleys Smart Dust


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Characteristics

Graphics:

AlexandraNolte

,GesineMarwedel,2003

P.Marwedel



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Many Implementation Choices

MicroprocessorsDomain-specific processors

DSP

Network processors

Microcontrollers

ASIPsApplication-specific instruction-set processor

Reconfigurable SoC

FPGA

Gatearray

ASICApplication-specific integrated circuit

Speed Power Cost

High LowVolume



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Characteristics of Embedded Systems (1)

Must be dependable,

Reliability R(t) = probability of system working correctlyprovided that is was working at t=0

Maintainability M(d) = probability of system workingcorrectly dtime units after error occurred.

Availability A(t): probability of system working at time t

Safety: no harm to be caused

Security: confidential and authentic communication

Even perfectly designed systems can fail if the assumptionsabout the workload and possible errors turn out to be wrong.Making the system dependable must not be an after-thought,it must be considered from the very beginning

1.1 terms and scope P.Marwedel



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Must be efficient

Energy efficient

Code-size efficient(especially for systems on a chip)

Run-time efficient Weight efficient

Cost efficient

Dedicated towards a certain applicationKnowledge about behavior at design time can be used tominimize resources and to maximize robustness

Dedicated user interface (no mouse, keyboard and screen)

P.Marwedel



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Many ES must meet real-time constraints A real-time system must react to stimuli from the controlled

object (or the operator) within the time interval dictated by theenvironment.

For real-time systems, right answers arriving too late are wrong.

A real-time constraint is called hard, if not meeting that

constraint could result in a catastrophe [Kopetz, 1997].

All other time-constraints are called soft.

A guaranteed system response has to be explained withoutstatistical arguments

P.Marwedel



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Real-Time Systems

Embedded and Real-Time Synonymous?

Most embedded

systems arereal-time

Most real-time

systems areembedded

embedded

real-time

embedded

real-time

Jakob Engblom

P.Marwedel



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Frequently connected to physical environmentthrough sensors and actuators

Hybrid systems (analog + digital parts).

Typically, ES are reactive systems:

A reactive system is one which is in continual

interaction with is environment and executes at a

pace determined by that environment [Berg, 1995]Behavior depends on input and current state.

automata model appropriate,

model of computable functions inappropriate.

P.Marwedel



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Quite a number of challenges, e.g. dependability

Dependability?

Non-real time protocols used for real-time applications

Over-simplification of models(e.g. aircraft anti-collision system)

Using unsafe systems for safety-critical missions(e.g. voice control system in Los Angeles; ~ 800planes without voice connection to tower for > 3 hrs

P.Marwedel


M L


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Moores Law

In 1965, Gordon Moore noted that the number of transistors on a chipdoubled every 18 to 24 months

He made a prediction that semiconductortechnology will double itseffectiveness every 18 months

16

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

1959

1960

1961

1962

1963

1964

1965

1966

1967

1968

1969

1970

1971

1972

1973

1974

1975

LOG2

OFT

HENUMBER

OF

COMPONENTSPER

INTEGRATED

FUNCTION

Electronics, April 19, 1965.


Moores law in Microprocessors


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Moore s law in Microprocessors

4004

80088080

8085 8086

286386

486Pentium proc

P6

0.001

0.01

0.1

1

10

100

1000

1970 1980 1990 2000 2010

Year

Transisto

rs(MT)

2X growth in 1.96 years!

Transistors on Lead Microprocessors double every 2 years

Courtesy, Intel


Die Size Growth


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Die Size Growth

40048008

80808085

8086286

386 486

Pentium procP6

1

10

100

1970 1980 1990 2000 2010

Year

Diesiz

e(mm)

~7% growth per year

~2X growth in 10 years

Die size grows by 14% to satisfy Moores Law

Courtesy, Intel


E b dd d HW M L


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Embedded HW: Moores Law

Margarshack03

65nm1400Kgates/mm2

45nm

2600Kgates/mm

2

STMicroelectronicsRoadmap

P.Marwedel


F


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Frequency

P6

Pentium proc486

38628680868085

8080

80084004

0.1

1

10

100

1000

10000

1970 1980 1990 2000 2010

Year

Frequen

cy(Mhz)

Lead Microprocessors frequency doubles every 2 years

Doubles every2 years

Courtesy, Intel

Now its over!



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Power is a major problem

5KW18KW

1.5KW

500W

40048008

80808085

8086286

386486

Pentium proc

0.1

1

10

100

1000

10000

100000

1971 1974 1978 1985 1992 2000 2004 2008

Year

Power(Watts)

Power delivery and dissipation will be prohibitive

Courtesy, Intel

Hard bound


Power density


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Power density

40048008

8080

8085

8086

286386

486Pentium proc

P6

1

10

100

1000

10000

1970 1980 1990 2000 2010

Year

PowerDens

ity(W/cm2)

Hot Plate

Nuclear

Reactor

RocketNozzle

Power density too high to keep junctions at low temp

Courtesy, Intel



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Not Only Microprocessors

Digital Cellular Market

(Phones Shipped)

1996 1997 1998 1999 2000

Units 48M 86M 162M 260M 435MAnalog

Baseband

Digital Baseband

(DSP + MCU)

Power

Management

Small

Signal RFPower

RF

(data from Texas Instruments)

CellPhone



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Challenges in Digital Design

Microscopic Problems Ultra-high speed design

Interconnect Noise, Crosstalk

Reliability, Manufacturability

Power Dissipation

Clock distribution.

Everything Looks a Little Different

Macroscopic Issues Time-to-Market

Millions of Gates High-Level Abstractions

Reuse & IP: Portability

Predictability

Verification

and Theres a Lot of Them!

DSM 1/DSM

?


Design productivity gap


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1

10

100

1,000

10,000

100,000

1,000,000

10,000,000

2003

1981

1983

1985

1987

1989

1991

1993

1995

1997

1999

2001

2005

2007

2009

10

100

1,000

10,000

100,000

1,000,000

10,000,000

100,000,000

Logic Tr./Chip

Tr./Staff Month.

xxx

xxx

x

21%/Yr. compound

Productivity growth rate

x

58%/Yr. compoundedComplexity growth rate

10,000

1,000

100

10

1

0.1

0.01

0.001

Logic

Trans

istorper

Ch

ip(M)

0.01

0.1

1

10

100

1,000

10,000

100,000

Pro

duc

tiv

ity

(K)Trans./

Staff-

Mo

.

Source: Sematech

Complexity outpaces design productivity

Comp

lex

ity

ITRS Roadmap

1981 leading edge chip required 100 designer months 10,000 transistors / 100 transistors/month

2002 leading edge chip requires 30,000 designer months 150,000,000 / 5000 transistors/month

Designer cost increase from $1M to $300M

Design productivity gap


The mythical man month


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The mythical man-month

The situation is even worse than the productivity gap indicatesIn theory, adding designers to team reduces project completion timeIn reality, productivity per designer decreases due to complexities of team

management and communicationIn the software community, known as the mythical man-month (Brooks 1975)At some point, can actually lengthen project completion time! (Too many cooks)

10 20 30 400

10000

20000

30000

40000

50000

60000

43

24

19

1615

1618

23

Team

Individual

Months until completion

Number of designers

1M transistors, 1 designer=5000trans/month

Each additional designer reducesfor 100 trans/month

So 2 designers produce 4900trans/month each

P.Marwedel


Challenges for implementation in hard are


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Challenges for implementation in hardware

Lack of flexibility (changing standards).

Mask cost for specialized HW becomes very expensive

[http://www.molecularimprints.com/Technology/tech_articles/MII_COO_NIST_2001.PDF9]

Trendtowardsimplementationin Software

P.Marwedel


Situation Worse in S/W



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Situation Worse in S/W

0

5

10

15

20

25

30

35

40

45

1980 1982 1984 1986 1988 1990 1992 1994

Hardware

Software

Embedded System Costs

Billion$/Y

ear


Software complexity is a challenge


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Software complexity is a challenge

Rob van Ommering, COPA Tutorial, as cited by: Gerrit Mller:

Opportunities and challenges in embedded systems,Eindhoven Embedded Systems Institute, 2004

Exponential increase in softwarecomplexity

In some areas code size isdoubling every 9 months [STMicroelectronics, Medea Workshop, Fall2003]

... > 70% of the development costfor complex systems such asautomotive electronics and

communication systems are dueto software development[A. Sangiovanni-Vincentelli, 1999]

P.Marwedel


Challenges for Embedded Software


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Challenges for Embedded Software

Dynamic environments

Capture the required behaviour!

Validate specifications

Efficient translation of specificationsinto implementations!

How can we check that we meet real-time constraints?

How do we validate embedded real-time software? (large volumes of data,testing may be safety-critical)

P.Marwedel


It is not sufficient to consider ES


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just as a special case of software engineering

CS EE

EE knowledge must be available,Walls between EE and CS must be torn down

P.Marwedel


Hardware/software design flow


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Hardware/software design flow

requirements and

specification

architecture

hardware design software design

integration

testing

P.Marwedel


Co-design methodology


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Co-design methodology

Must architect hardware and software together: provide sufficient resources; avoid software bottlenecks.

Can build pieces somewhat independently, butintegration is major step.

Also requires bottom-up feedback.

P.Marwedel


Hierarchical design flow


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Hierarchical design flow

Embedded systems must be designed across multiplelevels of abstraction: system architecture; hardware and software systems; hardware and software components.

Often need design flows within design flows.

P.Marwedel


Hierarchical HW/SW flow


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Hierarchical HW/SW flow

spec

architecture

HW SW

integrate

test

system

spec

HW architecture

detailed design

integration

test

hardware

spec

SW architecture

detailed design

integration

test

software

P.Marwedel


Codesign in time


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Fabrication Test

Codesign in time

Systemdesign

ASIC design

SW design

PCB test

SW test

Time

Tasks

Copyright J. Madsen,

some modifications applied

Traditional System Design Process


Codesign in time II


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Codesign in time II

Shared Design

Co-Design Process

SW design

ASIC design Fabrication Test

PCB test

SW test

Time

Tasks

Systemdesign

System-Level Partitioning


Goals of computer-aidedhardware/software co design


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hardware/software co-design

Explore different design alternatives Search for the best solution

Reduce system design time Reduce product time to market

Support coherent design specification Facilitate hardware and software reuse

Provide integrated environment for synthesis and validationof hardware and software components


Synthesis


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Synthesis

Specification

Detailed Representationof Implementation

Synthesis

HW: HDL(Behavioral,

DataFlow, Structural),Schematic

RTL, Gate level,

Transistors,Layout

SW:Algorithm,

Textual/Graphicalrepresentation

Executable orCompilable

code: Theprogram(s), OS

routines

Co-Synthesis


System architecture


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System architecture

CPU

accelerator

memory

I/OSoftware

Hardware


HW/SW co-design process


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/S co des g p ocess

co-design & synthesis

evaluation (co-simulation)

architecture design,

HW/SW partitioning

and interfacing

HW design SW design

co-specification

reused functions

and processes

process impl. &

transformations

HW architecture

and components

high-level

transformation

system

architect

results

customer/marketing

systems architect

SW

developer

HW

developer

system analysis

reused and

manually optimized

HW and SW components


Example: GPS moving map requirements


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p g p q

Moving map obtains

position from GPS,paints map from local

database.

lat: 40 13 lon: 32 19

I-78

ScotchRoad


GPS moving map needs


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g p

Functionality: For automotive use. Show major roads andlandmarks.

Userinterface: At least 400 x 600 pixel screen. Three buttonsmax. Pop-up menu.

Performance: Map should scroll smoothly. No more than 1 secpower-up. Lock onto GPS within 15 seconds.

Cost: $500 street price = approx. $100 cost of goods sold.

Physical size/weight: Should fit in hand.

Power consumption: Should run for 8 hours on four AA batteries.


GPS moving map block diagram


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g p g

GPS

receiver

search

enginerenderer

user

interfacedatabase

display


GPS moving map hardware architecture


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g p

GPS

receiver

CPU

panel I/O

display frame

buffer

memory


GPS moving map software architecture


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g p

position database

searchrenderer

timeruser

interface

pixels


System integration


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Must spend time architecting the system before you start

coding.

Some components are ready-made, some can be modifiedfrom existing designs, others must be designed from

scratch.

Put together the components.Many bugs appear only at this stage.

Have a plan for integrating components to uncover bugsquickly, test as much functionality as early as possible.

EES01-Embeded Sys. Introduction

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