Module-3

Embedded System Components: Embedded Vs General computing system,

Classification of Embedded systems, Major applications and purpose of ES. Core of
an Embedded System including all types of processor/controller, Memory, Sensors,
Actuators, LED, 7 segment LED display, Optocoupler, Relay, Piezo buzzer, Push
button switch, Communication Interface (onboard and external types), Embedded
firmware, Other system components.
(Text 2: All the Topics from Ch-1 and Ch-2, excluding 2.3.3.4 (stepper motor), 2.3.3.8
(keyboard) and 2.3.3.9 (PPI) sections). L1, L2, L3

MODULE-3
EMBEDDED SYSTEM COMPONENTS:
 EMBEDDED VS GENERAL COMPUTING SYSTEM,
 CLASSIFICATION OF EMBEDDED SYSTEMS,
 MAJOR APPLICATIONS AND PURPOSE OF ES.
 CORE OF AN EMBEDDED SYSTEM INCLUDING ALL TYPES OF PROCESSOR/CONTROLLER,
 MEMORY,
 SENSORS,
 ACTUATORS,
 LED,
 7 SEGMENT LED DISPLAY,
 OPTOCOUPLER,
 RELAY,
 PIEZO BUZZER,
 PUSH BUTTON SWITCH,
 COMMUNICATION INTERFACE (ONBOARD AND EXTERNAL TYPES),
 EMBEDDED FIRMWARE,
 OTHER SYSTEM COMPONENTS.

(TEXT 2: ALL THE TOPICS FROM CH-1 AND CH-2, EXCLUDING 2.3.3.4 (STEPPER MOTOR), 2.3.3.8
(KEYBOARD) AND 2.3.3.9 (PPI) SECTIONS). L1, L2, L3

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 EMBEDDED VS GENERAL COMPUTING SYSTEM
1. What is an Embedded System?

2. Embedded System vs. General Computing System

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DETAILS OF THE TOPICS
1. What is an Embedded System?
It is the simple definition statement from which, we should be able to understand the meaning of
ES i.e. ES are ment for single functioned applications and they require both hardware and
software...
2. Embedded System vs. General Computing System
Here if you go through the above table, few highlighting comparisons are given; let us discuss them
one by one.
#1 and 2 are related to the software and hardware requirements, we can observe here that GPCS
can be built with a general hardware design ,with general OS like windows series or even Linux
OS, where as for ES the hardware should be specific and also OS required will be real-time OS
like Linux, Vx-works etc.
#3 and 4 are about are about application types
#5 is about power requirements i.e. in case of ES power can be used at different modes but GPCS
can also operate at different power levels but GPCS are not flexible in terms of power utility.
#6 and 7 are self explainatory.

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 CLASSIFICATION OF EMBEDDED SYSTEMS

1. Based on Generation
Generation CPU Capacity Coding Style/OS Hardware/Software Example
First 4/8 bit .ASM Simple/Simple 8085
Second 16 bit .ASM,.C Complicated/Updated SCADA
But yet better than
previous
Third 32 bit .ASM,.C Complicated/Updated ASICS/DSP
But yet better than
previous
Fourth >32 bit .ASM,.C and Complicated/Updated Soc, Smart
others But yet better than phones etc
previous
Next?

2. Complexity and Performance Requirements.

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 TEXT
SSE
MSE
LSE

Small Scale Embedded Systems: 

These types of embedded systems are designed with a single 8-bit or 16-bit microcontroller.
They have tiny scaled hardware, software complexities and involve board-level design.
They may even be battery operated.
When embedded software is developing for this tiny scaled hardware, an editor, an assembler or cross assembler,
specific to the microcontroller or processor used, are the main programming tools.
Usually, ‘C programming language’ is used for developing these systems. ‘C’ program compilation is done into
the assembly, and executable codes are then appropriately located in the system memory.
The software has to fit within the memory existing and keep in view the need to limit power dissipation when
system is running continuously.

Medium Scale Embedded Systems: 

These systems are usually designed with a single or few 16-bit or 32-bit microcontrollers or Digital Signal
Processor (DSPs) or Reduced Instruction Set Computers (RISCs) being used.
These system have both hardware and software complexities. For complex software design of medium scale
embedded system, there are the following programming tools: RTOS, Source code engineering tool, Simulator,
Debugger and Integrated Development Environment (IDE).
Software tools also give the clarifications to the hardware complexities.
An assembler is of slight use as a programming tool.
These systems may also utilize the readily available Application-Specific Standard Product (ASSPs) and IPs for
the various functions.
For example, for the bus interfacing, encrypting, deciphering, discrete cosine transformation and inverse
transformation, TCP/IP protocol is stacking and network connecting functions.

Sophisticated Embedded Systems: 

Sophisticated embedded systems have massive hardware 32bit or 64bit controllers and software complexities and
may require ASIPs, IPs and PLAs scalable or configurable processors and programmable logic arrays.
They are used for cutting edge applications that require hardware and software co-design and integration in the
final system.

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 They are constrained by the processing speeds available in their hardware units. Certain software functions such
as encryption and deciphering algorithms Development tools for these systems may not be readily available at a
reasonable cost or may not be available at all.
In some cases, a compiler or retargetable (Compiler configures according to the specific target) compiler might
have to be developed for these.

 TOPICS COVERED HERE ARE TILL 23/03/2020

EMBEDDED VS GENERAL COMPUTING SYSTEM and CLASSIFICATION OF EMBEDDED

SYSTEMS.

Further notes will be attached by tomorrow morning.

24/03/2020

Major Application Area

[Page no 7 onwards in text or page 35 in pdf]

The embedded systems have a huge variety of application domains which varies from
very low cost to very high cost and from daily life consumer electronics to industry
automation equipments, from entertainment devices to academic equipments, and from
medical instruments to aerospace and weapon control systems. So, the embedded systems
span all aspects of our modern life. The following table gives the various applications of
embedded systems.

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The application areas and the products in the embedded domain are Countless. A few of the
important domains and products are listed below:

i. Consumer electronics: Camcorders, cameras, etc.

ii. Household appliances: Television, DVD players, washing machine, fridge,

microwave oven, etc.
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iii. Home automation and security systems: Air conditioners, sprinklers,
intruder detection alarms, closed circuit television cameras, fire alarms, etc.

iv. Automotive industry: Anti-lock breaking systems (ABS), engine control,

ignition systems, automatic navigation systems, etc.

v. Telecom: Cellular telephones, telephone switches, handset multimedia

applications, etc.

vi. Computer peripherals: Printers, scanners, fax machines, etc.

vii. Computer Networking systems: Network routers, switches, hubs,

firewalls, etc.

viii. Healthcare: Different kinds of scanners, EEG, ECG machines etc.

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 ix. Measurement & Instrumentation: Digital multi meters, digital CROs,
logic analyzers PLC systems, etc.

x. Banking & Retail: Automatic teller machines (ATM) and currency

counters, point of sales (POS).

xi. Card Readers: Barcode, smart card readers, hand held devices, etc.

Purpose of Embedded Systems

Embedded systems are used in various domains like consumer electronics, home
automation, telecommunications, automotive industry, healthcare, control &
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instrumentation, retail and banking applications, etc. Within the domain itself,
according to the application usage context, they may have different functionalities.
Each embedded system is designed to serve the purpose of any one or a combination of
the following tasks:
 Data collection/Storage/Representation
 Data Communication
 Data (signal) processing
 Monitoring
 Control
 Application specific user interface

1. Data Collection/Storage/Representation
 Embedded systems designed for the purpose of data collection perform
acquisition of data from the external world.
 Data collection is usually done for storage, analysis, manipulation and
transmission.
 The term “data” refers all kinds of information, such as text, voice, image,
video, electrical signals and any other measurable quantities.
 Data can be either analog (continuous) or digital (discrete).
 Embedded systems with analog data capturing techniques collect data directly
in the form of analog signal whereas embedded systems with digital data
collection mechanism converts the analog signal to the digital signal using
analog to digital (A/D) converters and then collects the binary equivalent of
the analog data.
 If the data is digital, it can be directly captured without any additional
interface by digital embedded systems.
 The collected data may be stored directly in the system or may be transmitted
to some other systems or it may be
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 processed by the system or it may be deleted instantly after giving a
meaningful representation.
 These actions are purely dependent on the purpose for which the embedded
system is designed.
 Embedded system designed for pure measurement applications without
storage, used in control and instrumentation domain, collects data and gives a
meaningful representation of the collected data by means of graphical
representation or quantity value and deletes the collected data when new
arrives at the data collection terminal.
 Analog and digital CROs without storage memory are typical examples of
this. Any measuring equipment used in the medical domain for monitoring
without storage functionality also comes under this category.
 A digital camera is a typical example of an embedded system with data
collection/storage/representation of data.Images is captured and the captured
image may be stored within the memory of the camera. The captured image
can also be presented to the user through a graphic LCD unit.

2. Data Communication

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 Embedded data communication systems are deployed in applications from
complex satellite communication systems to simple home networking systems.
 The data collected by an embedded terminal may require transferring of the same
to some other system located remotely.
 The transmission is achieved either by a wire-line medium or by a wire-less
medium.
 Wire-line medium was the most common choice in all olden days embedded
systems.
 As technology is changing, wireless medium is becoming the standard for data
communication in embedded systems. It offers cheaper connectivity solutions
and make the communication link free from the hassle of wire bundles.
 The data collecting embedded terminal itself can incorporate data communication
units like Wireless modules (Bluetooth, ZigBee, Wi-Fi, EDGE, GPRS, etc.) or
wire-line modules (RS-232C, USB, TCP/IP, PS2,etc).

 Certain embedded systems act as a dedicated transmission unit between the

sending and receiving terminals, offering sophisticated functionalities like data
packetizing, encrypting and decrypting.
 Network hubs, routers, switches, etc. are typical examples of dedicated data
transmission embedded systems.

 They act as mediators in data communication and provide various features like
data security, monitoring etc.

3. Data (Signal) Processing

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 The data (voice, image, video, electrical signals and other measurable quantities)
collected by embedded systems may be used for various kinds of data
processing.
 Embedded systems with signal processing functionalities are employed in
applications demanding signal processing like speech coding, synthesis, audio
video codec, transmission applications, etc.
 A digital hearing aid is a typical example of an embedded system employing
data processing. Digital hearingaid improves the hearing capacity of hearing
impaired persons.

4. Monitoring
 Almost all embedded products coming under the medical domain are with
monitoring functions only.
 They are used for determining the state of some variables using input sensors.
They cannot impose control over variables.
 A very good example is the electro cardiogram (ECG) machine for monitoring
the heartbeat of a patient. The machine is intended to do the monitoring of the
heartbeat of a patient but it cannot impose control over the heartbeat. The sensors
used in ECG are the different electrodes connected to the patient’s body.

 Other examples with monitoring function are measuring instruments like digital
CRO, digital multimeters, logic analyzers., etc. used in control & instrumentation
applications. They are used for knowing (monitoring) the status of some
variables like current, voltage, etc. They cannot control the variables in turn.

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5. Control

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6. Applications specific user interface

ASSIGNMENT BASED ON ABOVE TOPICS

1. What is an embedded system? Explain the different
applications of embedded systems.
2. Difference between embedded systems and general
computing systems
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 3. Describe the various purposes of embedded systems. Explain
any two in detail with illustrative examples.

27/03/2020
2.1 CORE OF THE EMBEDDED SYSTEM
Objectives
1. Introduction
2. Core of embedded systems
  General purpose and domain specific processor.
Microprocessors
Microcontrollers.
Digital signal processors
Application Specific Integrated Circuits. (ASIC)
Programmable logic devices (PLD’s)
Commercial off-the-shelf components(COTs)
3. Memory, Sensors & Actuators
4. Communication Interface

After reading this chapter you will be able to:

Understand the different types of core i.e. processor
Understand difference between microprocessor & microcontroller
  Understand the classification of processors based on Bus Architecture, Instruction set
Architecture and Endianness.

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 Have an overview of processors from most simple and cheap to most expensive and
complex, powerful
  Understand what are sensors and actuators, communication interfaces

Introduction
The first two chapters attempted on explain what an embedded system is about
and what the working parts are. This chapter attempts to go deeper and explain the core
of embedded system along with other related topics.

CORE OF EMBEDDED SYSTEMS

Embedded systems are domain and application specific and are built around a central
core. The core of the embedded system falls into any of the following categories:
 
1. General purpose and Domain Specific Processors
Microprocessors
1.2 Microcontrollers
Digital Signal Processors
2. Application Specific Integrated Circuits. (ASIC)
3. Programmable logic devices (PLD’s)
4. Commercial off-the-shelf components (COTs)

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