Download pdf - Module 5 Input Output Storage Devices

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�� !!!!!!!!�� COMPUTER PARTS & COMPONENTS

INPUT DEVICES OUTPUT DEVICES

STORAGE DEVICES

PUSAT PERKEMBANGAN KURIKULUM KEMENTERIAN PELAJARAN MALAYSIA

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MODULE 5

INPUT DEVICES OUTPUT DEVICES

STORAGE DEVICES

Curriculum Development Centre Ministry of Education Malaysia

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1. Name of Module : Computer Parts and Components –Input Devices, Output Devices and Storage Devices. 2. Learning Outcomes: Students should be able to:

a. identify and list the input devices

b. state the respective functions of input devices

c. identify and list the output devices

d. state the respective functions of output devices

e. identify and list the storage devices

f. state the functions of storage devices

g. identify the differences between primary and secondary storage

devices

h. state the units for data measurement

3. Knowledge and Skills

a. identify main components of computer system

b. state the computer system unit

c. identify the different types of peripheral

4. Module Summary: At the end of the module, students should be able to identify

input, output and storage devices and their functions respectively.

This module contains 3 activities:

Activity 1: Input devices

Activity 2: Output devices

Activity 3: Storage devices

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Activity 1: INPUT DEVICES Input devices are electronic devices connected to a computer that produce input signals. Below are some of the examples of input devices.

A keyboard is an example of input device for typing text. Figure 1.1 - Keyboard A scanner is an example of input device for copying graphic as well as text input. Figure 1.2 - Scanner

A microphone (Figure 1.3) is an example of input device used for audio input. A webcam (Figure 1.4) is an example of an input device for video input. Figure 1.3 - Microphone

A mouse is also an input device but it is called a pointing device used to input data into a computer. Figure 1.5 - Mouse

Figure 1.4 - webcam

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a. Input Devices for Texts Input devices for text is used to enter information into the computer by pressing the keys on a keyboard (Figure 1.6), virtual keyboard (Figure 1.7) on the screen, Optical reader (Figure 1.8) or Bar Code reader (Figure 1.9).

An optical reader is a device that uses a light source to read characters, marks and codes and then converts them into digital data, that a computer can process.

b. Input Devices for Graphics

Input devices for graphics are used to capture images. For example, a scanner (Figure 1.10) is an input device that captures images from photographic prints, posters, magazine pages and similar sources for computer editing and display. A digital camera (Figure 1.11) is used to take pictures and store the photographed images digitally.

Figure 1.11 - DIGITAL CAMERA Figure 1.10 - SCANNER

Figure 1.6 - KEYBOARD Figure 1.7 - VIRTUAL KEYBOARD

Figure 1.8 OPTICAL READER &

Figure 1.9 BAR CODE READER

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c. Input Devices for Audio

Audio input is the speech, music and sound effects entered into the computer. This can be done using input devices such as a microphone (Figure 1.12) and digital musical instruments like the Musical Instrument Digital Interface (MIDI) keyboard (Figure 1.13).

d. Input Devices for Video

Video input are motion images captured into the computer by special input devices. A Closed-Circuit Television (CCTV) (Figure 1.14) video camera is a type of digital video camera that enables a home or small business user to capture video and still images. A webcam (Figure 1.15) is a video camera that displays its output on a web page, in the internet. A digital video camera (Figure 1.16) allows the user to record full motion and store the captured motion digitally.

Figure 1.12 - Microphone Figure 1.13 – Midi Keyboard

Figure 1.14 – CCTV Camera Figure 16 – Digital Video Camera Figure 1.15 – Webcam

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e. Pointing Devices

A pointing device is another form of input device. Pointing devices such as a mouse, trackball, graphics tablet and touch screen are used to input spatial data into the computer. Spatial data refers to data that is continuous and multi-dimensional.

Figure 1.17 - mouse

Figure 1.18 - trackball Figure 1.19 – graphics tablet

Figure 1.20 – touch screen

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Activity 2: OUTPUT DEVICES

An output device is hardware that is capable of delivering or showing information to one or more users. An output device shows, prints and presents the results of a computer’s work.

Types of Output Devices a. Monitor

A display device is an output device that visually conveys texts, graphics and video information. A monitor is an example of an output device that can be used to display text. It can also display graphics and video. It is similar to a television set that accepts video signals from a computer and displays information on its screen. LCD Monitor (Figure 2.1) is an example of output device.

Figure 2.1 - LCD MONITOR

Figure 2.0 – Examples of output devices

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b. Printer

A printer is an output device that can be used to print text, apart from graphics, on mediums such as paper, transparency film or even cloths. A photo printer is a colour printer that produces photo quality pictures. An image setter produces high quality output compared to an ordinary laser printer. An image setter is a high resolution output device that can transfer electronic text and graphics directly to film, plates, or photo-sensitive paper.

c. Audio

An audio output device produces music, speech or other sounds. A pair of speakers is an audio output device that generates sound. The headphone is a pair of small speakers placed over the ears and plugged into a port on the sound card. A woofer or subwoofer is used to boost the low bass sound and is connected to the port on the sound card.

Figure 2.2 - Examples of output devices

SPEAKER HEADPHONE WOOFER

Figure 2.3 – Examples of audio devices

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d. Other output devices

Other output devices include Liquid Crystal Display (LCD) projectors and facsimile (fax) machines. A Liquid Crystal Display (LCD) projector uses its own light source to project what is displayed on the computer on a wall or projection screen. A digital light processing (DLP) projector uses tiny mirrors to reflect light which can be seen clearly in a well-lit room.

Figure 2.4 - Liquid Crystal Display (LCD)

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Activity 3: STORAGE DEVICES What Is Computer Storage? Information and documents are stored in a computer storage so that it can be retrieved whenever they are needed later on. Computer storage holds of data in an electromagnetic form to be accessed by a computer processor.

Types of Computer Storage

1. Primary storage 2. Secondary storage

a. PRIMARY STORAGE

Primary storage is the main memory in a computer. It stores data and programs that can be accessed directly by the processor.

Types Of Primary Storage

There are two types of primary storage which are RAM and ROM. RAM is a short form for Random-Access Memory which means the data and program in RAM can be read and written.

Figure 3.1

ROM is a short form for Read-Only Memory. The data or program in ROM can just be read but cannot be written at all. Figure 3.2

PENDRIVE DISKETT HARD DISK CD-ROM

Figure 3.0 – Storage Devices

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Random-Access Memory (RAM)

RAM is installed inside computers. RAM is also known as a working memory.

The data in RAM can be read (retrieved) or written (stored). RAM is volatile which means the programs and data in RAM

are lost when the computer is powered off. A computer uses RAM to hold temporary instructions and

data needed to complete tasks. This enables the computer CPU (Central Processing Unit) to access instructions and data stored in the memory very quickly.

RAM stores data during and after processing. Read-Only Memory (ROM)

ROM is another type of memory permanently stored inside the computer.

ROM is non-volatile. It holds the programs and data when the computer is powered off.

Programs in ROM have been pre-recorded. It can only be stored by the manufacturer once done, it cannot be changed.

It has complex functions such as start up operating instructions, translators for high-level languages and operating systems are placed in ROM memory.

All the contents in ROM can be accessed and read but cannot be changed.

b. SECONDARY STORAGE

Secondary storage is another alternative storage to keep your work and documents. It is very useful to store programs and data for future use. It is non-volatile, which means that it does not need power to maintain the information stored in it. It will store the information until it is erased.

Figure 3.3 - RAM

Figure 3.4 - ROM

Figure 3.5 – Secondary Storage

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Types Of Secondary Storage

Figure 3.6 Examples of Secondary Storage

Magnetic Medium Magnetic Medium is a non-volatile storage medium. It can be any type of storage medium that utilizes magnetic patterns to represent information. The devices use disks that are coated with magnetically sensitive material. Example of magnetic storage are:

magnetic disk such as: a floppy disk, used for off-line storage hard disk, used for secondary storage magnetic tape; including video cassette, audio

storage reel-to-reel tape and others.

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Optical Medium

Optical Medium is a non-volatile storage media that holds content in digital form that are written and read by a laser. These media include various types of CDs and DVDs. These following forms are often commonly used :

CD, CD-ROM, and DVD: Read only storage, used for distribution of digital information such as music, video and computer programmes.

CD-R: Write once storage, the data cannot be erased or written over once it is saved. CD-RW, DVD-RW and DVD-RAM: Slow to write but fast reading storage; it allows

data that has been saved to be erased and rewritten. Optical media has more advantages over magnetic media such as the disk capacity. One optical disk holds about the equivalent of 500 floppy disks worth of data. Durability is another feature of optical media, they are able to last for up to seven times as long as traditional storage media.

Flash Memory Flash Memory is a solid-state, non-volatile, rewritable memory that functions like RAM and a hard disk drive. Flash memory store bits of electronic data in memory cells just like DRAM (Dynamic RAM), but it also works like a hard disk drive. Flash memory cards and flash memory sticks are examples of flash memory. Flash memory cards are also used with digital cellular phones, MP3 players, digital video cameras and other portable digital devices. Flash memory is also called USB drives, thumb drives, pen drives or flash drives which are the up-and coming players in the portable storage market.

The advantages of flash memory are: offers fast reading access times among the secondary storage devices (though not as fast as RAM) it is durable and requires low voltage. It is also light and small. The disadvantage is, it is more expensive than the magnetic disk of the same capacity.

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c. THE DIFFERENCES BETWEEN PRIMARY AND SECONDARY STORAGE

PRIMARY STORAGE SECONDARY STORAGE

Known as the main memory of a computer. Alternative storage in a computer.

RAM / ROM. Examples : Floppy disc, Hard disk, CD-ROM, USB drive

Storage capacity is limited. Storage capacity is larger.

An internal memory (inside the CPU) that can be accessed directly by the processor.

Refers to various ways a computer can store program and data.

Has a volatile memory for RAM and non-volatile memory for ROM.

Is non-volatile, which means that it does not need power to maintain the information stored in it.

Units for data measurement

• Bit • Byte • Kilobyte (KB) • Megabyte (MB) • Gigabyte (GB)

Basic terminology

• 8 Bits = 1 Byte • 1024 Byte = 1 KB • 1,048,576 Bytes = 1024 KB = 1 MB • 1,073,741,824 Bytes = 1024 MB = 1 GB

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Laser printer Output device Flash card Tape Bar code Pen drive Flat panel monitor

1. Identification code consists of vertical line and spaces of different width is known

as _________________________ 2. __________ storage requires sequential access. 3. A _____________ is commonly used as the ‘film’ for digital cameras. 4. __________________ is any type of hardware component that conveys information

to one or more people.

5. An LCD monitor is also called _______________ that produces harp, flicker free images.

6. A ______________ is a flash memory storage device that plugs in a USB port. 7. _____________ is a high speed, high quality non impact printer.

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Exercise 2 Identify the type of input these devices produce. Tick (/) in the appropriate column

Devices Text Audio Graphics Video Pointing

1. Microphone

2. Keyboard

3. Webcam

4. Scanner

5. Bar Code Scanner

6. Mouse

Exercise 3 Mark on the types of output each device produces.

Device

Text

Graphic

Audio

Video

Monitor

Printer

LCD Projector

Speakers

Headphone

Facsimile Machine

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�Tick (/) the correct answer.

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A display device is an output device that visually conveys text.

2

Microphone produces music.

3 A Photo printer is a colour printer that produces photo

quality pictures.

4 Output is the result of raw input data that has been processed by

the Central Processing Unit into meaningful information.

5 A Liquid Crystal Display (LCD) projector uses its own light

source to project what is displayed on the computer on a wall or projection screen

6 A digital light processing (DLP) projector uses large mirrors to

reflect light which can be seen clearly in a well-lit room.

7 A video camera is an electronic device used to capture and

store photographs digitally

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Reference Cashman, S. (2006) Discovering Computers 2006. USA : Thomson Course Technology. Ibrahim Ahmad, Mohd Hafiz et al (2007) Information and Communication Technology (ICT) Based on SPM Syllabus. Selangor: Venton Publishing (M) Sdn Bhd. NCC Education (2002) Computer Studies, Computer Ace. Sri Lanka : Computer Pioneers. Basic Computing (2003) by TMEdu Tech (M) Sdn Bhd http://www.wikipedia.org http://images.search.yahoo.com http://www.google.com.my CD courseware ICT, PPK KPM