Embedded Systems: Block diagram, applications, advantages and disadvantages

 

Embedded Systems: Block diagram, applications/examples, advantages and disadvantages, 

 (Embedded system basics)

Definition of embedded system:

         Embedded system is the dedicated system which performs specific tasks and is the combination of hardware and software. In another words embedded system is the system in which software is embedded in to computer which is used for a dedicated purpose. Embedded system is used in plenty of applications, some applications are listed below.

 

Applications of embedded system:

        1. Smart cards (like ATM card, RC card of vehicle, swipe card for attendance etc.)

        2. Mobile phones

        3. Digital cameras

        4. Washing machine and microwave oven

        5. Vending machine (coffee/tea/chocolate/soft drink vending machines)

        6. Robots

        7. Digital clocks

        8. Point of sales terminals (POS)

        9. CD/DVD players

        10.  ATM machines

        11.  Set top box

        12.  HD TV’s

        13.  Security systems

        14.  Telephone and banking

        15.  Motor and cruise control systems in automobiles

        16.  Defense systems

        17.  wireless communication systems

        18.  Multitasking toys

        19.  Network and printers

        20.  Missiles

        21.  Satellites

        22.  Consumer electronics products

        23.  PDA (Personal digital assistant)

        24.  Pager

   And so on.

 

Block diagram of embedded system:

This section is about different components of embedded systems. 

Figure: Block diagram of embedded systems

As we seen the definition of embedded system in previous section, here is the block diagram of embedded system which consists of input and output devices, memory and communication interfaces. Now functions of blocks.

            1.      CPU (Processors): In embedded systems, CPU i.e central processing unit is most important and plays vital role of all arithmetic and logical operations. It consists of registers (to store the data) and logic units. Depending upon the application, 8-bit, 16-bit, 32-bit or 64-bit processors are used.

            2.      Input and output devices: As name indicates, input and output devices (I/O devices) are used in give the input and produce the output according to given input. I/O devices consists of keyboard, mouse, touch screen etc, and output devices like monitor, printer, plotter, displays etc.

            3.      Memory: In general sense, ROM (read only memory) and RAM (Random Access Memory) are used to store program instructions and user data respectively. As embedded systems are used for dedicated applications and do not need frequent programming, one time programmable (OTP) memories are used.

            4.      Communication interfaces: As embedded system consists of different devices, communication interfaces like USB, Ethernet, RS232 etc. communication interfaces are used which provide facility to connect I/O devices easily.

        Some features of embedded systems

            1.      These are specific purpose and dedicated computer systems.

            2.      Generally configured as Non User Programmable.

            3.      Produced in bulk which trims the cost.

          4.      The mobile and remotely operated devices which works on battery usually needs severe power budget constraints to enhance their battery life.

           5.      All such systems are usually application specific hence general purpose peripheral interfaces are absent.

            6.      Any Embedded System should have less Memory Requirement.

Advantages and disadvantages of embedded system:

Advantages:

            1.      Design and Efficiency

            2.      Cost

            3.      Accessibility

            4.      Maintenance

            5.      Redundancies

 1.      Design and Efficiency: As embedded systems are used for specific/dedicated applications hence CPU used in embedded system is less complicated which makes its design simple. The limited functions of embedded systems make design simple and efficient to perform their function.

2.      Cost: The simplified design of most embedded system allows their parts to be smaller less expensive to produce.

3.      Accessibility: In case of malfunction with a certain embedded systems, they cannot be too accessible to repair. This problem is solved in the design stage by programming an embedded system. 

4.      Maintenance: Embedded systems are easier to maintain because the supplied power is embedded in the system and does not required remote maintenance.

5.      Redundancies: Embedded system does not involve the redundant programming.

Disadvantages:

        1.      It is designed to perform specific task only, multitasking operations are not possible.

        2.      It is difficult to upgrade the machine

        3.      Harder to carry files from one machine to another

       4.      Most of the systems are battery operated hence there is big issue of life of battery and performance.

        Outcome of this topic: To understand the embedded system and its different aspects.