IT FOR Managers - They are notes provided by the University of Calicut PDF

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I T FORMANAGERSII SEMESTERInformation Technology for ManagersFundamentals of computers- Evolution of Computing Machines, Input/output devices, Microprocessors, binary number system, generation of computers and programming languages– Algorithms and Flowcharting - Hardware and Software, Classification...

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I T FOR MANAGERS II SEMESTER

Information Technology for Managers Fundamentals of computers- Evolution of Computing Machines, Input/output devices, Microprocessors, binary number system, generation of computers and programming languages– Algorithms and Flowcharting - Hardware and Software, Classification of software - Operating systems, Computer Block diagram. Networking of computers. LAN, WAN, Enterprise - wide networks, Internet technologies, WWW and Internet uses. E- mail, Electronic payment systems, Websites and their uses. WAP, VPN, E-commerce Information Systems for Management Decision Support Concepts of Data, Information and knowledge. Concepts of Database Management Systems, Processing of data using computers. Storage and Retrieval of massive data on computers. MIS, Phases in software Systems Life Cycle. Application of Information systems in Use in Business Use of Information systems in Business and their advantages. Application areas, problems Packages for Accounting and Finance, Decision Support Systems, Knowledge Based Systems., EIS, Cyber crimes and cyber laws. Computer viruses Computerization - Prospects and Problems - Information Technology as a strategic tool for achieving competitive edge in Business and Industry. Infrastructure Requirement, Selection of Hardware and Software, Implementation and transition problems. Skills up gradation and re-deployment of staff as a result of computerization. Implementing issues, opportunities, challenges, problems and managing changes.

COMPUTER Computer is an electronic device that can perform a variety of operations in accordance with a set of instructions called program. A computer is a device that can be instructed to carry out sequences of arithmetic or logical operations automatically via computer programming. Modern computers have the ability to follow generalized sets of operations, called programs. These programs enable computers to perform an extremely wide range of tasks. Computers are used as control systems for a wide variety of industrial and consumer devices. This includes simple special purpose devices like microwave ovens and remote controls, factory devices such as industrial robots and computer-aided design, and also general purpose devices like personal computers and mobile devices such as smartphones. Computers are generally classified by size and power as follows, although there is considerable overlap. The differences between computer classifications generally get smaller as technology advances, creating smaller and more powerful and costfriendly components. ฀ Personal computer: a small, single-user computer based on a microprocessor. In addition to the microprocessor, a personal computer has a keyboard for entering data, a monitor for displaying information, and a storage device for saving data. ฀ Workstation: a powerful, single-user computer. A workstation is like a personal computer, but it has a more powerful microprocessor and a higher-quality monitor. ฀ Minicomputer: a multi-user computer capable of supporting from 10 to hundreds of users simultaneously. ฀ Mainframe: a powerful multi-user computer capable of supporting many hundreds or thousands of users simultaneously. ฀ Supercomputer: an extremely fast computer that can perform hundreds of millions of instructions per second.

Functioning of computer

FUNCTIONING UNITS OF A COMPUTER 1.

INPUT UNITS

The input unit is formed by the input devices attached to the computer. E.g : mouse, keyboard, scanner, etc

2. CENTRAL PROCESSING UNITS The control unit (often called a control system or central controller) manages the computer's various components; it reads and interprets (decodes) the program instructions, transforming them into control signals that activate other parts of the computer.[63] Control systems in advanced computers may change the order of execution of some instructions to improve performance. Central processing unit (CPU) The control unit, ALU, and registers are collectively known as a central processing unit (CPU). Early CPUs were composed of many separate components but since the mid-1970s CPUs have typically been constructed on a single integrated circuit called a microprocessor. Arithmetic logic unit (ALU) The ALU is capable of performing two classes of operations: arithmetic and logic. The set of arithmetic operations that a particular ALU supports may be limited to

addition and subtraction, or might include multiplication, division, trigonometry functions such as sine, cosine, etc., and square roots. Memory A computer's memory can be viewed as a list of cells into which numbers can be placed or read. Each cell has a numbered "address" and can store a single number. Computer main memory comes in two principal varieties: random-access memory or RAM  read-only memory or ROM RAM can be read and written to anytime the CPU commands it, but ROM is preloaded with data and software that never changes, therefore the CPU can only read from it. ROM is typically used to store the computer's initial start-up instructions. In general, the contents of RAM are erased when the power to the computer is turned off, but ROM retains its data indefinitely. 

3. OUTPUT UNIT The output unit is formed by the output devices attached to a computer. The output coming from the CPU is in the form of electronic binary signals which needs conversion in some form which can be easily understood by human beings i.e. graphics, audio, visual. E.g.: visual display unit(VDU)/monitor, speaker, printer.

Hardware Computer hardware includes the physical, tangible parts or components of a computer, such as the central processing unit, monitor, keyboard, computer data storage, graphic card, sound card, speakers and motherboard. Software Computer software, or simply software, is a collection of data or computer instructions that tell the computer how to work. This is in contrast to physical hardware, from which the system is built and actually performs the work.

In computer science and software engineering, computer software is all information processed by computer systems, programs and data. Computer software includes computer programs, libraries and related non-executable data, such as online documentation or digital media. Computer hardware and software require each other and neither can be realistically used on its own.

COMPUTER BLOCK DIAGRAM

1. Input: This is the process of entering data and programs in to the computer system. You should know that computer is an electronic machine like any other machine which takes as inputs raw data and performs some processing giving out processed data. Therefore, the input unit takes data from us to the computer in an organized manner for processing. 2. Storage: The process of saving data and instructions permanently is known as storage. Data has to be fed into the system before the actual processing starts. It is

because the processing speed of Central Processing Unit (CPU) is so fast that the data has to be provided to CPU with the same speed. Therefore the data is first stored in the storage unit for faster access and processing. This storage unit or the primary storage of the computer system is designed to do the above functionality. It provides space for storing data and instructions. The storage unit performs the following major functions: • All data and instructions are stored here before and after processing. • Intermediate results of processing are also stored here. 3. Processing: The task of performing operations like arithmetic and logical operations is called processing. The Central Processing Unit (CPU) takes data and instructions from the storage unit and makes all sorts of calculations based on the instructions given and the type of data provided. It is then sent back to the storage unit. 4. Output: This is the process of producing results from the data for getting useful information. Similarly the output produced by the computer after processing must also be kept somewhere inside the computer before being given to you in human readable form. Again the output is also stored inside the computer for further processing. 5. Control: The manner how instructions are executed and the above operations are performed. Controlling of all operations like input, processing and output are performed by control unit. It takes care of step by step processing of all operations inside the computer. FUNCTIONAL UNITS In order to carry out the operations mentioned in the previous section the computer allocates the task between its various functional units. The computer system is divided into three separate units for its operation. They are Arithmetic Logical Unit (ALU) Logical Unit: After you enter data through the input device it is stored in the primary storage unit. The actual processing of the data and instruction are performed by Arithmetic Logical Unit. The major operations performed by the ALU are addition, subtraction, multiplication, division, logic and comparison. Data is transferred to ALU from storage unit when required. After processing the output is returned back to storage unit for further processing or getting stored.

Control Unit (CU) The next component of computer is the Control Unit, which acts like the supervisor seeing that things are done in proper fashion. Control Unit is responsible for coordinating various operations using time signal. The control unit determines the sequence in which computer programs and instructions are executed. Things like processing of programs stored in the main memory, interpretation of the instructions and issuing of signals for other units of the computer to execute them. It also acts as a switch board operator when several users access the computer simultaneously. Thereby it coordinates the activities of computer’s peripheral equipment as they perform the input and output. Central Processing Unit (CPU) The ALU and the CU of a computer system are jointly known as the central processing unit. You may call CPU as the brain of any computer system. It is just like brain that takes all major decisions, makes all sorts of calculations and directs different parts of the computer functions by activating and controlling the operations.

INPUT/OUTPUT DEVICES Input devices (a)Keyboard It is a text base input device that allows the user to input alphabets, numbers and other characters. It consists of a set of keys mounted on a board.

(b) Mouse The mouse is a small device used to point to a particular place on the screen and select in order to perform one or more actions. It can be used to select menu commands, size windows, start programs etc. The most conventional kind of mouse has two buttons on top: the left one being used most frequently.

(c) Joystick The joystick is a vertical stick which moves the graphic cursor in a direction the stick is moved. It typically has a button on top that is used to select the option pointed by the cursor. Joystick is used as an input device primarily used with video games, training simulators and controlling robots.

(d)Scanner Scanner is an input device used for direct data entry from the source document into the computer system. It converts the document image into digital form so that it can be fed into the computer. Capturing information like this reduces the possibility of errors typically experienced during large data entry.

(e) Bar codes A bar code is a set of lines of different thicknesses that represent a number. Bar Code Readers are used to input data from bar codes. Most products in shops have bar codes on them. Bar code readers work by shining a beam of light on the lines that make up the bar code and detecting the amount of light that is reflected back.

(f) Light Pen It is a pen shaped device used to select objects on a display screen. It is quite like the mouse (in its functionality) but uses a light pen to move the pointer and select any object on the screen by pointing to the object. Users of Computer Aided Design (CAD) applications commonly use the light pens to directly draw on screen.

(g) Touch Screen It allows the user to operate/make selections by simply touching the display screen. Common examples of touch screen include information kiosks, and bank ATMs.

(h) The Speech Input Device The “Microphones - Speech Recognition” is a speech Input device. To operate it we require using a microphone to talk to the computer. Also we need to add a sound card to the computer. The Sound card digitizes audio input into 0/1s .A speech recognition program can process the input and convert it into machinerecognized commands or input.

Output Devices (a) Monitor Monitor is an output device that resembles the television screen and uses a Cathode Ray Tube (CRT) to display information. The monitor is associated with a keyboard for manual input of characters and displays the information as it is keyed in. It also displays the program or application output. Like the television, monitors are also available in different sizes. Liquid Crystal Display (LCD) LCD was introduced in the 1970s and is now applied to display terminals also. Its advantages like low energy consumption, smaller and lighter have paved its way for usage in portable computers (laptops).

(b) Printer Printers are used to produce paper (commonly known as hardcopy) output. Based on the technology used, they can be classified as Impact or Non-impact printers. Impact printers use the typewriting printing mechanism wherein a hammer strikes the paper through a ribbon in order to produce output. Dot-matrix and Character printers fall under this category. Non-impact printers do not touch the paper while printing. They use chemical, heat or electrical signals to etch the symbols on paper. Inkjet, DeskJet, Laser, Thermal printers fall under this category of printers. When we talk about printers we refer to two basic qualities associated with printers: resolution, and speed. Print resolution is measured in terms of number of dots per inch (dpi).

Print speed is measured in terms of number of characters printed in a unit of time and is represented as characters-per-second (cps), lines-per-minute (lpm), or pagesper-minute (ppm).

(c) Plotter Plotters are used to print ggraphical output on paper. It interprets computer commands and makes linee drawings on paper using multicolored automated pens. It is capable of producing graphs, drawings, charts, maps etc. Computer Aided Enginee ring (CAE) applications like CAD (Coomputer Aided Design) and CAM (Compputer Aided Manufacturing) are typical usage areas for plotters.

(e) Audio Output: Soun d Cards and Speakers The Audio output is the a bility of the computer to output sound Two components are needed: Sound card – Plays contents of digitized recordings, Speakers – Attached to sound card.

BINARY CODE A binary code represents text, computer processor instructions, or any other data using a two-symbol system. The two-symbol system used is often "0" and "1" from the binary number system. The binary code assigns a pattern of binary digits, also known as bits, to each character, instruction, etc. For example, a binary string of eight bits can represent any of 256 possible values and can, therefore, represent a wide variety of different items. In computing and telecommunications, binary codes are used for various methods of encoding data, such as character strings, into bit strings. Those methods may use fixed-width or variable-width strings. In a fixed-width binary code, each letter, digit, or other character is represented by a bit string of the same length; that bit string, interpreted as a binary number, is usually displayed in code tables in octal, decimal or hexadecimal notation. There are many character sets and many character encodings for them. A bit string, interpreted as a binary number, can be translated into a decimal number. For example, the lower case a, if represented by the bit string 01100001 (as it is in the standard ASCII code), can also be represented as the decimal number "97". Most modern computers use binary encoding for instructions and data. CDs, DVDs, and Blu-ray Discs represent sound and video digitally in binary form. Telephone calls are carried digitally on long-distance and mobile phone networks using pulse-code modulation, and on voice over IP networks.

MICROPROCESSOR A microprocessor is a computer processor that incorporates the functions of a central processing unit on a single integrated circuit (IC), or at most a few integrated circuits. The microprocessor is a multipurpose, clock driven, register based, digital integrated circuit that accepts binary data as input, processes it according to instructions stored in its memory and provides results as output. Microprocessors contain both combinational logic and sequential digital logic. Microprocessors operate on numbers and symbols represented in the binary number system. The integration of a whole CPU onto a single or a few integrated circuits greatly reduced the cost of processing power. Integrated circuit processors are produced in large numbers by highly automated processes, resulting in a low unit price. Singlechip processors increase reliability because there are many fewer electrical connections that could fail. As microprocessor designs improve, the cost of manufacturing a chip (with smaller components built on a semiconductor chip the same size) generally stays the same according to Rock's law. Before microprocessors, small computers had been built using racks of circuit boards with many medium- and small-scale integrated circuits. Microprocessors combined this into one or a few large-scale ICs. Continued increases in microprocessor capacity have since rendered other forms of computers almost completely obsolete (see history of computing hardware), with one or more microprocessors used in everything from the smallest embedded systems and handheld devices to the largest mainframes and supercomputers. INSHORT: Microprocessor is a controlling unit of a micro-computer, fabricated on a small chip capable of performing ALU (Arithmetic Logical Unit) operations and communicating with the other devices connected to it. Microprocessor consists of an ALU, register array, and a control unit. ALU performs arithmetical and logical operations on the data received from the memory or an input device. Register array consists of registers identified by letters like B, C, D, E, H, L and accumulator. The control unit controls the flow of data and instructions within the computer.

Block Diagram of a Basicc Microcomputer

How does a microp processor work? The microprocessor folloows a sequence: Fetch, Decode, and theen Execute Initially, the instructionss are stored in the memory in a seqquential order. The microprocessor fetches th hose instructions from the memory, then decodes it and executes those instructio ons till STOP instruction is reached. Later, it sends the result in binary to the output port. Between these processes, the register stores the temporarily data and ALU U performs the computing functions List of Terms Used in a M Microprocessor Here is a list of some of tthe frequently used terms in a micropro ocessor − 

Instruction Set − It is the set of instructions that the microprocessor m can understand.

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Bandwidth − It is the t number of bits processed in a single instruction.

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Clock Speed − It determines the number of operations per second the processor can perform. It is expressed in megahertz (MHz) or gigahertz (GHz).It is also known as Clock Rate.

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Word Length − It depends upon the width of internal data bus, registers, ALU, etc. An 8-bit microprocessor can process 8-bit data at a time. The word length ranges from 4 bits to 64 bits depending upon the type of the microcomputer.

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Data Types − The microprocessor has multiple data type formats like binary, BCD, ASCII, signed and unsigned numbers.

Special-purpose designs A microprocessor is a general-purpose ...