UNIT2_EMbedded_system5Gnsbsjxisiefcn.ppt

5G

1. Introduction to Introduction to
Embedded Embedded
SystemsSystems
ByBy
Dr. Sankari M.Dr. Sankari M.

2. 2
ObjectivesObjectives
•Introduction to embedded systemsIntroduction to embedded systems
•Embedded system componentsEmbedded system components
•HardwareHardware
•SoftwareSoftware
•Embedded system programmingEmbedded system programming
Introduction to Embedded Systems
Dr. Sankari M

3. 3
ContentsContents
•Introduction to embedded systemsIntroduction to embedded systems
•Software engineeringSoftware engineering
•Computer architectureComputer architecture
•Operating systemsOperating systems
•Digital systemsDigital systems
•Programming practiceProgramming practice
•Theory for practical worksTheory for practical works
Introduction to Embedded Systems
Dr. Sankari M

4. 4
Y. Williams Csci-339, Spring 2002 20
Wireless Communications
Hand-held GPS Units
Telematics System for Automobiles
Slide credit Y Williams, GWUSlide credit Y Williams, GWU
Introduction to Embedded Systems
Dr. Sankari M

5. 5
Y. Williams Csci-339, Spring 2002 22
Robotics Control
Spider robot –constructed with LEGO Mindstorms Components
Slide credit Y Williams, GWUSlide credit Y Williams, GWU
Introduction to Embedded Systems
Dr. Sankari M

6. 6
More examplesMore examples
Slide credit Y Williams, GWUSlide credit Y Williams, GWU
Y. Williams Csci-339, Spring 2002 24
Smart Toys
Introduction to Embedded Systems
Dr. Sankari M

7. 7
DefinitionDefinition

““Any sort of device which includes a Any sort of device which includes a
programmable computer but itself is not programmable computer but itself is not
intended to be a general-purpose intended to be a general-purpose
computercomputer””

Wayne WolfWayne Wolf
Introduction to Embedded Systems
Dr. Sankari M

8. 8
DefinitionDefinition
Slide credit P Koopman, CMUSlide credit P Koopman, CMU
Introduction to Embedded Systems
Dr. Sankari M

9. 9
Embedded systems overviewEmbedded systems overview

Computing systems are everywhereComputing systems are everywhere
Most of us think of “desktop” computersMost of us think of “desktop” computers
–PC’sPC’s
–LaptopsLaptops
–MainframesMainframes
–ServersServers
But there’s another type of computing systemBut there’s another type of computing system
–Far more common...Far more common...
Slide credit Vahid/Givargis, Embedded Systems Design: A Unified Hardware/Software Introduction, Slide credit Vahid/Givargis, Embedded Systems Design: A Unified Hardware/Software Introduction,
20002000
Introduction to Embedded Systems
Dr. Sankari M

10. 10
Embedded systems overviewEmbedded systems overview

Embedded computing systemsEmbedded computing systems
–Computing systems embedded Computing systems embedded
within electronic deviceswithin electronic devices
–Hard to define. Nearly any Hard to define. Nearly any
computing system other than a computing system other than a
desktop computerdesktop computer
–Billions of units produced yearly, Billions of units produced yearly,
versus millions of desktop unitsversus millions of desktop units
–Perhaps 50 per household and per Perhaps 50 per household and per
automobileautomobile
Slide credit Vahid/Givargis, Embedded Systems Design: A Unified Slide credit Vahid/Givargis, Embedded Systems Design: A Unified
Hardware/Software Introduction, 2000Hardware/Software Introduction, 2000
Computers are in here...
and here...
and even here...
Lots more of these,
though they cost a lot
less each.
Introduction to Embedded Systems
Dr. Sankari M

11. 11
A “short list” of embedded A “short list” of embedded
systemssystems
And the list goes on and onAnd the list goes on and on
Slide credit Vahid/Givargis, Embedded Systems Design: A Unified Hardware/Software Introduction, 2000Slide credit Vahid/Givargis, Embedded Systems Design: A Unified Hardware/Software Introduction, 2000
Anti-lock brakes
Auto-focus cameras
Automatic teller machines
Automatic toll systems
Automatic transmission
Avionic systems
Battery chargers
Camcorders
Cell phones
Cell-phone base stations
Cordless phones
Cruise control
Curbside check-in systems
Digital cameras
Disk drives
Electronic card readers
Electronic instruments
Electronic toys/games
Factory control
Fax machines
Fingerprint identifiers
Home security systems
Life-support systems
Medical testing systems
Modems
MPEG decoders
Network cards
Network switches/routers
On-board navigation
Pagers
Photocopiers
Point-of-sale systems
Portable video games
Printers
Satellite phones
Scanners
Smart ovens/dishwashers
Speech recognizers
Stereo systems
Teleconferencing systems
Televisions
Temperature controllers
Theft tracking systems
TV set-top boxes
VCR’s, DVD players
Video game consoles
Video phones
Washers and dryers
Introduction to Embedded Systems
Dr. Sankari M

12. 12
How many do we use?How many do we use?

Average middle-class home has 40 to 50 Average middle-class home has 40 to 50
embedded processors in it embedded processors in it
–Microwave, washer, dryer, dishwasher, TV, VCR, Microwave, washer, dryer, dishwasher, TV, VCR,
stereo, hair dryer, coffee maker, remote control, stereo, hair dryer, coffee maker, remote control,
humidifier, heater, toys, etc. humidifier, heater, toys, etc.

Luxury cars have over 60 embedded processorsLuxury cars have over 60 embedded processors
–Brakes, steering, windows, locks, ignition, dashboard Brakes, steering, windows, locks, ignition, dashboard
displays, transmission, mirrors, etc. displays, transmission, mirrors, etc.

Personal computers have over 10 embedded Personal computers have over 10 embedded
processors processors
–Graphics accelerator, mouse, keyboard, hard-drive, CD-Graphics accelerator, mouse, keyboard, hard-drive, CD-
ROM, bus interface, network card, etc. ROM, bus interface, network card, etc.
- Mike Schulte- Mike Schulte
Introduction to Embedded Systems
Dr. Sankari M

13. 13
Types of Embedded SystemsTypes of Embedded Systems
Introduction to Embedded Systems
Dr.
Sankari M
Embedded Systems
Dr. S
Introduction to Embedded Systems
Dr. Sankari M

14. 14
Types of Embedded SystemsTypes of Embedded Systems
Slide credit S. Kowalewski Aachen UniversitySlide credit S. Kowalewski Aachen University
Introduction to Embedded Systems
Dr. Sankari M

15. 15
Typical Embedded SystemsTypical Embedded Systems

Are designed to observed (through sensors) Are designed to observed (through sensors)
and control something (through actuators)and control something (through actuators)
E.g. air condition senses room temperature and E.g. air condition senses room temperature and
maintains it at set temperature via thermostat.maintains it at set temperature via thermostat.
Introduction to Embedded Systems
Dr. Sankari M

16. 16
Embedded System Block DiagramEmbedded System Block Diagram
Slide credit Y Williams, GWUSlide credit Y Williams, GWU
Processor
mem
Observe
(Input)
Control
(Output)
Motor/Light
Temperature
Sensor
S
y
s
t
e
m

B
u
s
Introduction to Embedded Systems
Dr. Sankari M

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ProcessorsProcessors

Microprocessors for PCsMicroprocessors for PCs

Embedded processors or Microcontrollers Embedded processors or Microcontrollers
for embedded systemsfor embedded systems
–Often with lower clock speeds Often with lower clock speeds
–Integrated with memory and Integrated with memory and
–I/O devices e.g. A/D D/A PWM CANI/O devices e.g. A/D D/A PWM CAN
–Higher environmental specsHigher environmental specs
Introduction to Embedded Systems
Dr. Sankari M

18. 18
Types of Embedded ProcessorsTypes of Embedded Processors

Computational micros (32- or 64-bit datapaths)Computational micros (32- or 64-bit datapaths)
–CPU of workstations, PCs, or high-end portable devices (PDAs)CPU of workstations, PCs, or high-end portable devices (PDAs)
–x86, PA-RISC, PowerPC, SPARC, etc. x86, PA-RISC, PowerPC, SPARC, etc.

Embedded general purpose micros (32-bit datapaths)Embedded general purpose micros (32-bit datapaths)
–Designed for a wide range of embedded applicationsDesigned for a wide range of embedded applications
–Often scaled-down version of computational microsOften scaled-down version of computational micros
–ARM, PowerPC, MIPS, x86, 68K, etc. ARM, PowerPC, MIPS, x86, 68K, etc.

Microcontrollers (4-, 8-, or 16-bit datapaths)Microcontrollers (4-, 8-, or 16-bit datapaths)
–Integrate processing unit, memory, I/O buses, and peripheralsIntegrate processing unit, memory, I/O buses, and peripherals
–Often low-cost, high-volume devicesOften low-cost, high-volume devices

Domain-specific processors (datapath size varies greatly)Domain-specific processors (datapath size varies greatly)
–Designed for a particular application domainDesigned for a particular application domain
–Digital signal processors, multimedia processors, graphics Digital signal processors, multimedia processors, graphics
processors, network processors, security processors, etc. processors, network processors, security processors, etc.
Slide credit - Mike SchulteSlide credit - Mike Schulte
Introduction to Embedded Systems
Dr. Sankari M

19. 19
Processor MarketProcessor Market

2001 processor market by volume:2001 processor market by volume:
–Computational micros: 2%Computational micros: 2%
–Embedded general-purpose micros: 11%Embedded general-purpose micros: 11%
–DSPs: 10%DSPs: 10%
–Microcontrollers: 80%Microcontrollers: 80%
2001 processor market by revenue:2001 processor market by revenue:
–Computational micros: 51%Computational micros: 51%
–Embedded general-purpose micros: 8%Embedded general-purpose micros: 8%
–DSPs: 13%DSPs: 13%
–Microcontrollers: 28%Microcontrollers: 28%

Higher growth expected for embedded micros, DSPs, and Higher growth expected for embedded micros, DSPs, and
microcontrollersmicrocontrollers
Slide credit - Mike SchulteSlide credit - Mike Schulte
Introduction to Embedded Systems
Dr. Sankari M

20. 20
Some common characteristics of embedded Some common characteristics of embedded
systemssystems
Single-functionedSingle-functioned
–Executes a single program, repeatedlyExecutes a single program, repeatedly
Tightly-constrainedTightly-constrained
–Low cost, low power, small, fast, etc.Low cost, low power, small, fast, etc.

Reactive and real-timeReactive and real-time
–Continually reacts to changes in the system’s Continually reacts to changes in the system’s
environmentenvironment
–Must compute certain results in real-time Must compute certain results in real-time
without delaywithout delay
Slide credit Vahid/Givargis, Embedded Systems Design: A Unified Hardware/Software Introduction, 2000Slide credit Vahid/Givargis, Embedded Systems Design: A Unified Hardware/Software Introduction, 2000
Introduction to Embedded Systems
Dr. Sankari M

21. 21
Characteristics of Embedded SystemsCharacteristics of Embedded Systems

Application-specific functionality – specialized for one or one Application-specific functionality – specialized for one or one
class of applicationsclass of applications

Deadline constrained operation – system may have to perform Deadline constrained operation – system may have to perform
its function(s) within specific time periods to achieve successful its function(s) within specific time periods to achieve successful
resultsresults

Resource challenged – systems typically are configured with a Resource challenged – systems typically are configured with a
modest set of resources to meet the performance objectivesmodest set of resources to meet the performance objectives

Power efficient – many systems are battery-powered and must Power efficient – many systems are battery-powered and must
conserve power to maximize the usable life of the system.conserve power to maximize the usable life of the system.

Form factor – many systems are light weight and low volume to Form factor – many systems are light weight and low volume to
be used as components in host systemsbe used as components in host systems

Manufacturable – usually small and inexpensive to manufacture Manufacturable – usually small and inexpensive to manufacture
based on the size and low complexity of the hardware.based on the size and low complexity of the hardware.
Slide credit Y William, GWUSlide credit Y William, GWU
Introduction to Embedded Systems
Dr. Sankari M

22. 22
Design ConstraintsDesign Constraints
Slide credit – P Koopman, CMUSlide credit – P Koopman, CMU
Introduction to Embedded Systems
Dr. Sankari M

23. 23
Design ChallengesDesign Challenges
Does it really work?Does it really work?
–Is the specification correct?Is the specification correct?
–Does the implementation meet the spec?Does the implementation meet the spec?
–How do we test for real-time characteristics?How do we test for real-time characteristics?
–How do we test on real data?How do we test on real data?
How do we work on the system?How do we work on the system?
–Observability, controllability?Observability, controllability?
–What is our development platform?What is our development platform?
Slide credit – P Koopman, CMUSlide credit – P Koopman, CMU
More importantly – optimising design More importantly – optimising design
metrics!!metrics!!
Introduction to Embedded Systems
Dr. Sankari M

24. 24
Design MetricsDesign Metrics
•Common metricsCommon metrics
•Unit cost: Unit cost: the monetary cost of manufacturing each copy of the monetary cost of manufacturing each copy of
the system, excluding NRE costthe system, excluding NRE cost
•NRE cost (Non-Recurring Engineering cost): NRE cost (Non-Recurring Engineering cost):
The one-time monetary cost of designing the systemThe one-time monetary cost of designing the system
•Size: Size: the physical space required by the systemthe physical space required by the system
•Performance: Performance: the execution time or throughput of the systemthe execution time or throughput of the system
•Power: Power: the amount of power consumed by the systemthe amount of power consumed by the system
•Flexibility: Flexibility: the ability to change the functionality of the the ability to change the functionality of the
system without incurring heavy NRE costsystem without incurring heavy NRE cost
Slide credit Vahid/Givargis, Embedded Systems Design: A Unified Hardware/Software IntroductionSlide credit Vahid/Givargis, Embedded Systems Design: A Unified Hardware/Software Introduction
Introduction to Embedded Systems
Dr. Sankari M

25. 25
Design MetricsDesign Metrics
•Common metrics (continued)Common metrics (continued)
•Time-to-prototype: Time-to-prototype: the time needed to build a working the time needed to build a working
version of the systemversion of the system
•Time-to-market: Time-to-market: the time required to develop a system to the time required to develop a system to
the point that it can be released and sold to customersthe point that it can be released and sold to customers
•Maintainability: Maintainability: the ability to modify the system after its the ability to modify the system after its
initial releaseinitial release
•Correctness, safety, many moreCorrectness, safety, many more
Slide credit Vahid/Givargis, Embedded Systems Design: A Unified Hardware/Software IntroductionSlide credit Vahid/Givargis, Embedded Systems Design: A Unified Hardware/Software Introduction
Introduction to Embedded Systems
Dr. Sankari M

26. 26
Trade-off in Design MetricsTrade-off in Design Metrics

Expertise with both Expertise with both
software and hardwaresoftware and hardware
is needed to optimize is needed to optimize
design metricsdesign metrics
–Not just a hardware or Not just a hardware or
software expert, as is software expert, as is
commoncommon
–A designer must be A designer must be
comfortable with various comfortable with various
technologies in order to technologies in order to
choose the best for a given choose the best for a given
application and constraintsapplication and constraints
Slide credit Vahid/Givargis, Embedded Systems Design: Slide credit Vahid/Givargis, Embedded Systems Design:
A Unified Hardware/Software IntroductionA Unified Hardware/Software Introduction
SizePerformance
Power
NRE cost
Introduction to Embedded Systems
Dr. Sankari M

27. 27
Time-to-market: a demanding design Time-to-market: a demanding design
metricmetric

Time required to develop Time required to develop
a product to the point it a product to the point it
can be sold to customerscan be sold to customers

Market windowMarket window
–Period during which the Period during which the
product would have highest product would have highest
salessales

Average time-to-market Average time-to-market
constraint is about 8 constraint is about 8
monthsmonths

Delays can be costlyDelays can be costly
Slide credit Vahid/Givargis, Embedded Systems Design: A Slide credit Vahid/Givargis, Embedded Systems Design: A
Unified Hardware/Software IntroductionUnified Hardware/Software Introduction
R
e
v
e
n
u
e
s
(
$
)
Time (months)
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Dr. Sankari M

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Losses due to delayed market Losses due to delayed market
entryentry

Simplified revenue modelSimplified revenue model
–Product life = 2W, peak at WProduct life = 2W, peak at W
–Time of market entry defines Time of market entry defines
a triangle, representing a triangle, representing
market penetrationmarket penetration
–Triangle area equals revenueTriangle area equals revenue

Loss Loss
–The difference between the The difference between the
on-time and delayed triangle on-time and delayed triangle
areasareas
Slide credit Vahid/Givargis, Embedded Systems Slide credit Vahid/Givargis, Embedded Systems
Design: A Unified Hardware/Software Design: A Unified Hardware/Software
IntroductionIntroduction
On-time Delayed
entry entry
Peak revenue
Peak revenue from
delayed entry
Market rise Market fall
W 2W
Time
D
On-time
Delayed
R
e
v
e
n
u
e
s
(
$
)
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Other Design ConsiderationsOther Design Considerations

DependabilityDependability
–Reliability: probability of system working Reliability: probability of system working
correctly provided that it worked at time t=0correctly provided that it worked at time t=0
–Maintainability: probability of system working Maintainability: probability of system working
correctly d time units after error occurred. correctly d time units after error occurred.
[[Some systems require no maintenance Some systems require no maintenance
throughout their operating lives (e.g. electric throughout their operating lives (e.g. electric
kettles, computer keyboards), while some may kettles, computer keyboards), while some may
need it such as mobile phones and airplane need it such as mobile phones and airplane
flight control (software upgrade)flight control (software upgrade)]]
Introduction to Embedded Systems
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30. 30
Other Design ConsiderationsOther Design Considerations

DependabilityDependability
–Availability: probability of system working at Availability: probability of system working at
time ttime t
–SafetySafety
–Security: in communicationSecurity: in communication
Basically, cBasically, critical applications have to operate ritical applications have to operate
correctly at all time e.g. airplane flight control correctly at all time e.g. airplane flight control
computer. This includes both computer. This includes both hardware and hardware and
softwaresoftware aspects. aspects.
Introduction to Embedded Systems
Dr. Sankari M

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Example of System FaultExample of System Fault
Slide credit B. PahamiSlide credit B. Pahami
Introduction to Embedded Systems
Dr. Sankari M

32. 32
Other Design ConsiderationsOther Design Considerations

OOperating environmentperating environment
Some engine Electronic Control Units (ECUs) in Some engine Electronic Control Units (ECUs) in
cars are located under the bonnets. So they have cars are located under the bonnets. So they have
to work at high temperature, as well as dusty to work at high temperature, as well as dusty
and wet environment.and wet environment.

EMI (Electromagnetic Interference)EMI (Electromagnetic Interference)
Introduction to Embedded Systems
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Real-Time ConsiderationReal-Time Consideration

Correct operation of real-time systems Correct operation of real-time systems
means:means:
–Working correctly (functionally correct)Working correctly (functionally correct)
–Producing outputs Producing outputs in timein time!!

i.e. correct result at the right timei.e. correct result at the right time
Introduction to Embedded Systems
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Hard Real-timeHard Real-time
System designed to meet all deadlinesSystem designed to meet all deadlines
A missed deadline is a design flawA missed deadline is a design flaw
For examples: ABS brake, nuclear reactor For examples: ABS brake, nuclear reactor
monitoring systemmonitoring system
System hardware (over) designed for worst-System hardware (over) designed for worst-
case performancecase performance
System software rigorously testedSystem software rigorously tested
Formal proofs used to guarantee timing Formal proofs used to guarantee timing
correctnesscorrectness
Slide credit – T GivargisSlide credit – T Givargis
Introduction to Embedded Systems
Dr. Sankari M

35. 35
Firm Real-timeFirm Real-time

System designed to meet all deadlines, but System designed to meet all deadlines, but
occasional missed deadline is allowedoccasional missed deadline is allowed
–Sometimes statistically quantified (e.g. 5% Sometimes statistically quantified (e.g. 5%
misses)misses)

For examples: multimedia systemsFor examples: multimedia systems

System hardware designed for average case System hardware designed for average case
performanceperformance
System software tested under average System software tested under average
(ideal) conditions(ideal) conditions
Slide credit – T GivargisSlide credit – T Givargis
Introduction to Embedded Systems
Dr. Sankari M

36. 36
Soft Real-timeSoft Real-time
System designed to meet as many deadlines System designed to meet as many deadlines
as possibleas possible
–Best effort to complete within specified time, Best effort to complete within specified time,
but may be latebut may be late
For examples: network switch or routerFor examples: network switch or router
System hardware designed for average case System hardware designed for average case
performanceperformance
System software tested under averaged System software tested under averaged
(ideal) conditions(ideal) conditions
Slide credit – T GivargisSlide credit – T Givargis
Introduction to Embedded Systems
Dr. Sankari M

37. 37
Deadlines
•Deadline: maximum time before
a task must complete
•The profit associated with execution of a task
is after the deadline:
–Hard deadline: negative
–Firm deadline: 0 (either make
it or just don’t do it)
–Soft deadline: decreasing
with time
time
d
task
p
r
o
fi
t d
time
soft
firm
hardSlide taken from J.J Lukkien
Real-time Systems DeadlinesReal-time Systems Deadlines
Introduction to Embedded Systems
Dr. Sankari M

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Levels of Embedded System DesignLevels of Embedded System Design
Slide credit – Ingo SanderSlide credit – Ingo Sander
Introduction to Embedded Systems
Dr. Sankari M

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Design AbstractionDesign Abstraction
Slide credit – Ingo SanderSlide credit – Ingo Sander
Introduction to Embedded Systems
Dr. Sankari M

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Abstraction LevelsAbstraction Levels
Slide credit – Ingo SanderSlide credit – Ingo Sander
Introduction to Embedded Systems
Dr. Sankari M

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Abstraction LevelsAbstraction Levels
Slide credit – Ingo SanderSlide credit – Ingo Sander
Introduction to Embedded Systems
Dr. Sankari M

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Abstraction LevelsAbstraction Levels
Slide credit – Ingo SanderSlide credit – Ingo Sander
Introduction to Embedded Systems
Dr. Sankari M

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Abstraction LevelAbstraction Level
Slide credit – Ingo SanderSlide credit – Ingo Sander
Introduction to Embedded Systems
Dr. Sankari M

44. 44
Hardware vs SoftwareHardware vs Software

Many functions can be done by Many functions can be done by softwaresoftware on on
a general purpose microprocessor a general purpose microprocessor OROR by by
hardwarehardware on an application specific ICs on an application specific ICs
(ASICs)(ASICs)

For examples: game console graphic, For examples: game console graphic,
PWM, PID controlPWM, PID control

Leads to Hardware/Software Co-design Leads to Hardware/Software Co-design
conceptconcept
Introduction to Embedded Systems
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Hardware or Software?Hardware or Software?
Where to place functionality?Where to place functionality?
–ex: A Sort algorithmex: A Sort algorithm
»Faster in hardware, but more expensive. Faster in hardware, but more expensive.
»More flexible in software but slower.More flexible in software but slower.
»Other examples?Other examples?

Must be able to explore these various trade-offs:Must be able to explore these various trade-offs:
–Cost.Cost.
–Speed.Speed.
–Reliability.Reliability.
–Form (size, weight, and power constraints.)Form (size, weight, and power constraints.)
Slide credit - Slide credit - W. McUmberW. McUmber,, MSU MSU
Introduction to Embedded Systems
Dr. Sankari M

46. 46
Hardware vs SoftwareHardware vs Software
Slide credit - Slide credit - Mike SchulteMike Schulte
Embedded
Application-Specific
Processors
Embedded
Domain-Specific
Processors
General-Purpose
Processors
FFT Processors
MPEG Processors
FIR Processors
Graphics Processors
DSP Processors
Network Processors
Workstations
Personal Computers
P
o
w
e
r
/
P
e
r
f
o
r
m
a
n
c
e
Programmability and Flexibility
Introduction to Embedded Systems
Dr. Sankari M

47. 47
Hardware vs SoftwareHardware vs Software
Slide credit – Ingo SanderSlide credit – Ingo Sander
Introduction to Embedded Systems
Dr. Sankari M

48. 48
General-purpose processorsGeneral-purpose processors
Slide credit Vahid/Givargis, Embedded Systems Design: A Unified Hardware/Software Introduction, 2000Slide credit Vahid/Givargis, Embedded Systems Design: A Unified Hardware/Software Introduction, 2000

Programmable device used in a variety of Programmable device used in a variety of
applicationsapplications
–Also known as “microprocessor”Also known as “microprocessor”

FeaturesFeatures
–Program memoryProgram memory
–General datapath with large register file and General datapath with large register file and
general ALUgeneral ALU

User benefitsUser benefits
–Low time-to-market and NRE costsLow time-to-market and NRE costs
–High flexibilityHigh flexibility

““Pentium” the most well-known, but Pentium” the most well-known, but
there are hundreds of othersthere are hundreds of others
IR PC
Register
file
General
ALU
DatapathController
Program memory
Assembly code for:
total = 0
for i =1 to …
Control
logic and
State
register
Data
memory
Introduction to Embedded Systems
Dr. Sankari M

49. 49
Single-purpose processorsSingle-purpose processors
Slide credit Vahid/Givargis, Embedded Systems Design: A Unified Hardware/Software Introduction, 2000Slide credit Vahid/Givargis, Embedded Systems Design: A Unified Hardware/Software Introduction, 2000

Digital circuit designed to execute exactly Digital circuit designed to execute exactly
one programone program
–a.k.a. coprocessor, accelerator or peripherala.k.a. coprocessor, accelerator or peripheral

FeaturesFeatures
–Contains only the components needed to Contains only the components needed to
execute a single programexecute a single program
–No program memoryNo program memory

BenefitsBenefits
–FastFast
–Low powerLow power
–Small sizeSmall size
DatapathController
Control
logic
State
register
Data
memory
index
total
+
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50. 50
Application-specific processorsApplication-specific processors
Slide credit Vahid/Givargis, Embedded Systems Design: A Unified Hardware/Software Introduction, 2000Slide credit Vahid/Givargis, Embedded Systems Design: A Unified Hardware/Software Introduction, 2000

Programmable processor optimized for a Programmable processor optimized for a
particular class of applications having particular class of applications having
common characteristicscommon characteristics
–Compromise between general-purpose and Compromise between general-purpose and
single-purpose processorssingle-purpose processors

FeaturesFeatures
–Program memoryProgram memory
–Optimized datapathOptimized datapath
–Special functional unitsSpecial functional units

BenefitsBenefits
–Some flexibility, good performance, size and Some flexibility, good performance, size and
powerpower
DSPDSP จัดอยู่ในประเภทนี
้ด้วย
จัดอยู่ในประเภทนี
้ด้วย
IR PC
Registers
Custom
ALU
DatapathController
Program memory
Assembly code for:
total = 0
for i =1 to …
Control
logic and
State
register
Data
memory
Introduction to Embedded Systems
Dr. Sankari M

51. 51
FPGA ArchitectureFPGA Architecture
FPGA layout with Configurable Logic Blocks (CLB) and I/O Blocks (IOB) FPGA layout with Configurable Logic Blocks (CLB) and I/O Blocks (IOB) (credit: Katz’s Contemporary Logic Design)(credit: Katz’s Contemporary Logic Design)
IOB IOB IOB IOB
CLB CLB
CLB CLB
I
O
B
I
O
B
I
O
B
I
O
B
Wiring Channels
Typical CLB (credit: www.wikipedia.com)
Programmable switch at wiring intersection
(credit: www.wikipedia.com)
Introduction to Embedded Systems
Dr. Sankari M

52. 52

Highly constrained products tend to use Highly constrained products tend to use
application specific processorsapplication specific processors
–Many mobile phones (power&size constrained) Many mobile phones (power&size constrained)
contain ARM chipscontain ARM chips
–Hi-Fi (high performance&time constrained) Hi-Fi (high performance&time constrained)
contain DSP chipscontain DSP chips
Introduction to Embedded Systems
Dr. Sankari M

53. 53
Software CostsSoftware Costs
Slide credit – P Koopman, CMUSlide credit – P Koopman, CMU
Introduction to Embedded Systems
Dr. Sankari M

54. 54
Future Embedded SystemsFuture Embedded Systems
Slide credit – P Koopman, CMUSlide credit – P Koopman, CMU
Introduction to Embedded Systems
Dr. Sankari M