ELEC 562 (Embedded Systems Design)
Lecture note 1
By: Dr. Nabil Bastaki
OVERVIEW OF EMBEDDED SYSTEMS
1
DEFINITIONS

What is an embedded system?
 An
embedded system is a special-purpose
computer system designed to perform one or a
few dedicated functions, often with real-time
computing constraints. It is usually embedded
as part of a complete device including hardware
and mechanical parts.[1]
Example: MP3 players, DVD players, etc.,
 How about Mobile phones?

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DEFINITIONS
In computer science, real-time computing (RTC) is the study of
hardware and software systems that are subject to a "real-time
constraint"—i.e., operational deadlines from event to system
response. [1]
 Example: Anti-lock brake system (ABS)

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ROUTER

A router, an example of an embedded system.
Labeled parts include a microprocessor (4), RAM
(6), and flash memory (7). [1]
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CHARACTERISTICS OF EMBEDDED SYSTEMS[1]

Designed to do some specific task, rather than be a general-purpose
computer for multiple tasks. Some may have real-time performance
constraints that must be met.

They are not always standalone devices. Many embedded systems consist of
small, computerized parts within a larger device that serves a more general
purpose.

The program instructions written for embedded systems are referred to as
firmware and are stored in read-only memory or Flash memory. They run
with limited computer hardware resources: little memory, small or nonexistent keyboard and/or screen.
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SYSTEM ON A CHIP (SOC)

Microcontroller
based SOC
One or more
Microcontroller /
microprocessor
 Memory blocks
 PLL & oscillators
 Timers/ power-on
reset
 Voltage regulator
 ADC/DAC
 USB interface,
Firewire
…

Microcontroller Based SOC[1]
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MICROPROCESSOR BASED SYSTEMS
Microprocessor
Input / Output
Registers
…
Memory
Serial
Comm.
ROM
Flash
RAM
Microprocessor, Memory and I/O on separate chips
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WHAT IS A MICROCONTROLLER?

A Computer-on-a-Chip
 CPU
(microprocessor)
 Read/Write memory
 Flash memory
 Read Only Memory (EEPROM)
 Analog to digital converts
 Serial Communication
…
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MICROCONTROLLER ARCHITECTURE
All on a Single
Chip
CPU
Input / Output
Registers
Memory
…
Serial
Comm.
ROM
Flash
RAM
9
WHO MAKES MICROCONTROLLERS?[2]

Some of the companies that make
Microcontrollers include:
•Intel
•Microchip
•ATmel
•Motorola
•Freescale
•Altera
•National Semiconductor
•Texas Instruments
•Toshiba
•Xilinx
•Zilog
•NEC
•Parallax
•Philips
•...
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WHERE ARE MICROCONTROLLERS USED?

Embedded systems



Minimal requirement for Memory, program length and I/O,
low power (battery operated), real time deadlines
Size matters
Examples
•Washing machines
•Telephones
•Microwave ovens
•Toys
•Cars
•Refrigerators
•Camcorders
•Anti-lock brakes
•Cruise control
•Televisions
•VCRs
•DVD players
•Mobile phones
•. . .
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EARLY MICROCONTROLLERS[3]
TI TMS 1000 (1974)
 Features

 4-bit
MCU,
 $2
 Used
in Speak & Spell
 Used in calculators

Intel 8048/8035 (1976)
 Used
in early IBM PC and compatible keyboards
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SPEAK AND SPELL
Speak and Spell includes a single TI TMS 1000 MCU[3]
13
ATMEL ATMEGA32 MICROCONTROLLER[4]

Key Parameters
 8-bit,
low power, RISC architecture
 32KB Flash
 1KB EEPROM
 2KB Internal SRAM (1K X 16)
 32 (max) I/O pins
 8 channel 10-bit A/D-converter
 16 (max) MHz
 VCC 2.7 – 5.5 Volts
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PRODUCT DEVELOPMENT
a.
b.
c.
d.
Product definition based on product knowledge and market
Product formal specification
A project team is assigned to create the product based on the formal specification
The team goes through the sequence:
1)
2)
3)
4)
5)
6)
7)
8)
Designing
Developing
Debugging
Verifying
Production planning
Production
Test
Shipping the product
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REFERENCES
1.
2.
3.
4.
http://www.wikipedia.org
http://www.HowStuffWorks.com
http://www.computerhistory.org/semiconductor/timeline
http://www.atmel.com
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