This document provides an introduction to embedded systems. It begins with defining what an embedded system and gives examples like televisions, cellphones, and GPS devices. It describes the typical components of an embedded system like a microprocessor, memory, I/O units. It discusses system designer considerations for choosing processors and constraints like available memory and power. It also categorizes different types of embedded systems such as stand-alone, real-time, networked, mobile, small-scale, and sophisticated embedded systems. Finally, it provides a task for writing the components and rules for some example embedded systems like a refrigerator, washing machine, air conditioner and ATM machine.

1. Introduction
to Embedded
Systems
Session 1
SURYAPRAKASH S
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2. Agenda
• Embedded System Definition
• Examples of Embedded System
• Component of Embedded System
• System Designer Consideration
• Categories of Embedded System
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3. Basics of Embedded System
System:
• A system is a way of working, organizing or doing one or many task according to a
fixed plan, program or set of rules.
Examples of Systems:
• Time display system – A watch
• Automatic cloth washing system – A washing machine
Embedded system:
• An embedded system is a system that has software embedded into computer-
hardware, which makes a system dedicated for an application (s) or specific part of
an application or product or part of a larger system.
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4. Examples of Embedded
System
• Television, Automobiles
• MP3, Cellphones
• GPS
• Microwave, home alarms
• Thermostats
• Network Router, Game Consoles
• ATM Machines
• Aircraft and Satellite,
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5. Components of Embedded System
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Microprocessor
Memory (primary + Secondary
I/O Units
Networking Units
Operating System

6. Components of Embedded System
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7. Components of Embedded System
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8. Characteristics of Embedded System
Real time and
Multirate
Operation
(control over
the latencies to
meet the
deadlines)
Complex
Algorithms
Complex
Graphics User
Interface(GUI)
and other user
interfaces
Dedicated
Function
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9. Constraints of Embedded System
Available
System
Memory
Available
Speed
Power Performance
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10. Components of Embedded System- Processor
Program Flow and data path Control Unit (CU) —includes a fetch
unit for fetching instructions from the memory
Execution Unit (EU) —includes circuits for arithmetic and logical
unit (ALU), and for instructions for a program control task, say,
data transfer instructions, halt, interrupt, or jump to another set
of instructions or call to another routine or sleep or reset
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11. System designer considerations
Processor Instructions in the Instruction set
Processor ability to solve the complex algorithms used in
meeting the deadlines for their processing.
Maximum bits in operand (8 or 16 or 32) in a single
arithmetic or logical operation.
Internal and External bus-widths in the data-path
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12. SYSTEM DESIGNER CONSIDERATIONS
Clock frequency in MHz and processing speed
Million
Instructions Per
Second (MIPS) or
Million Floating
Point Instructions
Per Second
(MFLOPS) or
Dhrystone– an
alternate metric
for measuring
processing
performance.
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13. What makes embedded systems different?
Real-time
operation
Size
cost
timeReliability
safety
energy
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14. Types of Embedded Systems
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15. Stand Alone Embedded Systems
• Stand alone embedded systems do not require a host system like a computer, it works by itself. It takes
the input from the input ports either analog or digital and processes, calculates and converts the data and
gives the resulting data through the connected device-Which either controls, drives and displays the
connected devices. Examples for the stand alone embedded systems are mp3 players, digital cameras,
video game consoles, microwave ovens and temperature measurement systems.
Real Time Embedded Systems
• A real time embedded system is defined as, a system which gives a required o/p in a particular time.
These types of embedded systems follow the time deadlines for completion of a task. Real time
embedded systems are classified into two types such as soft and hard real time systems.
Networked Embedded Systems
• These types of embedded systems are related to a network to access the resources. The connected
network can be LAN, WAN or the internet. The connection can be any wired or wireless. This type of
embedded system is the fastest growing area in embedded system applications. The embedded web
server is a type of system wherein all embedded devices are connected to a web server and accessed and
controlled by a web-browser. Example for the LAN networked embedded system is a home security
system wherein all sensors are connected and run on the protocol TCP/IP
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16. Mobile Embedded Systems
• Mobile embedded systems are used in portable embedded devices like cell phones, mobiles,
digital cameras, mp3 players and personal digital assistants, etc. The basic limitation of these
devices is the other resources and limitation of memory.
Small Scale Embedded Systems
• These types of embedded systems are designed with a single 8 or 16-bit microcontroller,
that may even be activated by a battery. For developing embedded software for small scale
embedded systems, the main programming tools are an editor, assembler, cross assembler
and integrated development environment (IDE).
Medium Scale Embedded Systems
• These types of embedded systems design with a single or 16 or 32 bit microcontroller, RISCs or
DSPs. These types of embedded systems have both hardware and software complexities. For
developing embedded software for medium scale embedded systems, the main programming
tools are C, C++, JAVA, Visual C++, RTOS, debugger, source code engineering tool, simulator
and IDE.
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17. Sophisticated Embedded Systems
• These types of embedded systems have enormous
hardware and software complexities, that may need ASIPs,
IPs, PLAs, scalable or configurable processors. They are used
for cutting-edge applications that need hardware and
software Co-design and components which have to
assemble in the final system.
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18. TASK
Write the list of components and the rules for the
following embedded system
1. Refrigerator
2. Washing machine
3. Air Conditioner
4. ATM Machine
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