Mobile & embedded system:Introduction

Lin ZhongELEC424, Fall 2010

System vs. processor/IC vs. “chip” System

Ready to interface with the physical world, including human users

Usually has non-computing components Battery, display, microphone, motor, etc.

System > Chip >=processor/IC Non silicon components hard to integrate

into chip: “Board” vs. “Chip” System on a chip (SoC)

Processor + silicon components of a system2

Embedded systems Physical

Component of a larger system Functional

More or less fixed set of applications Programming

Foreign application development Code compile on a different computer

Not necessarily small, inexpensive or standalone

What are not embedded systems? Super computers, servers Personal computers

A rough definition of embedded systems A computing system that is not called super computer, server, or

personal computer3

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Mobile systems Great computing

capacity Established social

acceptance Individual ownership Unbeatable portability

Wireless

Display

HCIBattery

Moore’s Law

5

Samsung S5L8900 412MHz

128MB RAM/8-16GB Flash

WiFi, Bluetooth 2.0, 3G 4.7 oz

Intel Pentium MMX 233MHz

64MB RAM/4GB Disk Ethernet 14 pounds

IBM Thinkpad 770 (1998)

Computing capacity

Apple iPhone (2008)

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Established social acceptance

60% population have a cell phone (2009) 3.3 billions (ITU 2008) 800 millions accessed Internet through phones

80% population live under cellular network coverage (2006) 90% phone lines in Africa are mobile phones

1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 20100

1000

2000

3000

4000

5000

6000

7000

World population Mobile cellular subscribers

Personal computers Internet users

Nu

mb

er i

n m

illi

on

s

Source: ITU/Business Today

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But… Limited I/O capacity

Between the device & its physical context Especially its user! No Moore’s Law for human capacity

Limited battery capacity No Moore’s Law for battery capacity

Limited heat dissipation capacity No Moore’s Law for thermodynamics

Limited human attention

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Computing vs. human performance

Sources: intel.com and factmonster.com

1968 1972 1976 1980 1984 1988 1992 1996 2000 20041

10

100

1000

10000

100000

1000000

Olympic Gold Metal winner: 100m dash (men)Olympic God Metal winner: 100m dash (women)# of transistors for Intel processorProcessor performance measured in MIPS

Year

Tim

es

of

imp

rov

em

en

t

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Computing vs. humanity

1965 1970 1975 1980 1985 1990 1995 2000 20050.000001

0.00001

0.0001

0.001

0.01

0.1

1

10

USA Federal minimum wage in 2003 dollar

Average transistor price for Intel processors in contemporary dollar

US

A $

Source: Intel.com and dol.gov

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Text entry speed

Speaking mini hardware keyboard

Software key-board with stylus

Handwriting0

20

40

60

80

100

120

140

160

180

150

2313 15

25 2212 7

Raw speed

Corrected speed

Sp

ee

d (

wo

rds

pe

r m

inu

te)

Raw speeds do not improve

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Samsung S5L8900 412MHz

128MB RAM/8-16GB Flash

WiFi, Bluetooth 2.0, 3G 4.7 oz

Intel Pentium MMX 233MHz

64MB RAM/4GB Disk Ethernet 14 pounds

IBM Thinkpad 770 (1998)

If you could use only one computer

Apple iPhone (2008)

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Limited battery capacity Mobile devices are weight-sensitive Battery density increases about 10% annually

1950 Nickel Cadmium (NiCd) 1990 Nickel-metal Hydride (NiMH) 1991 Lithium Ion (Li-ion) 1999 Li-ion Polymer

Most devices have battery capacity within 1500mAh, typically slightly more than 1000mAh (@3-5V) Nokia 9500 communicator: 1300mAh (@3-5V) Li-ion

Polymer, 172 grams Dell Latitude D610: 4700mAh (@11V) Li-ion, 2300 grams

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Limited heat transfer capacity No active thermal management

Better packaging material Energy storage with phase-change

materials

Thermal management of a thin laptop

Source: Intel Technology JournalWater cooling of a high-end PC

Source: water-cooling.com

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A hot case: 3-Watt Nokia 3120

Phone case temperature will be 40 deg C higher.

Every one Watt increases surface temperature by about 13 deg C

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Design challenges Limited I/O capacity

No Moore’s Law for human capacity Limited battery capacity

No Moore’s Law for battery capacity Limited heat dissipation capacity

No Moore’s Law for thermodynamics Limited human attention

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Design challenges (Contd.) It is NOT about computing

1990 1992 1994 1996 1998 2000 2002 2004 200610

100

1000

10000

0

200

400

600

800

1000

24

33

66

150

Gateway highend desktopGateway laptopNokia 9xxx communicatorNokia 9xxx weight (g)Nokia 9xxx volume (cc)

Year of introduction

Pro

cess

or

spee

d in

MH

z

Wei

gh

t (g

)/V

olu

mn

e(cc

)

9000

91109210

9500

Source: Dr. Cutler and Nokia.com

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Design challenges (Contd.) It is about

Integrating heterogeneous components Making computing (energy) efficient

Low-power design Thermal management

Making computing useful Make users more productive Make users healthier Make them happier Get more users

ELEC424 in ECE curriculum

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User interfaceApplication software

(including domain-specific solutions, compilers, software engineering)

Operating system (including network, file system, device

drivers)

Processor Digital IC RF

circuit Display Battery etc

System

integration

Major components System

Board, system on chip, Embedded computing

ARM, TI MSP430 Low-power design Real-time concepts Control

Non-computing elements Sensors, batteries, displays etc. Human factors

System development Windows Mobile, Linux, iPhone

Applications Health, automobile, telecommunication, entertainment etc.

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From Tilt 1 to Tilt 2 Tilt 1 was a sensor node

Tilt 2 will be the control system for a Quadrotor

New this year (Contd.)

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Lectures & homework

Project building a complete embedded

system

Build a complete embedded system System and function design Printed circuit board design &

fabrication Board assembly Operating system installation Program

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Administrative info. Homework 10% Participation 10% Presentation 20% In class quiz 10% Mid term 20% Final 30%

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Blink check point http://www.youtube.com/watch?v=M

OJyYXPwe-E

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Tilt check point http://www.youtube.com/watch?v=s

7OANI1LelE

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Balance check point http://www.youtube.com/watch?v=4

kmJuIE8G8U

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Lift and balance http

://www.youtube.com/watch?v=n6uC6AasfJo

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