Basic Computer Fundamentals

Introduction A calculating machineis an electronic machine, operating under the control of operating instructions stored in its own memory, that can accept entropy, manipulate the data according to specified rules, produce results, and store the results for hereafter use. Computers process data to create information. Datais a collection of raw unprocessed facts, figures, and symbols. Informationis data that is organized, meaningful, and useful. To process data into information, a computer uses hardw be and software. Hardwareis the electric, electronic, and windup(prenominal) equipment that makes up a computer.Softwareis the serial of instructions that tells the hardware how to perform tasks. Characteristics of Computers 1 Automatic Requires human intervention to start any task, solve difficulty but once initiated, it continues the job until its completed. 2 Speed in terms of microseconds (10 might -6), nanoseconds(10 position -9), and even picoseconds (10 power -12). A powerf ul computer is capable of performing several billions simple arithmetic operations per second. restrict by hardware and software resources. 3 Accuracy garbage-in-garbage-out (GIGO).E. g. Human enter error, programmer logic error. 4 Diligence foreign human beings, a computer is free from monotony, tiredness, and lack of concentration. 5 Versatility Can perform multiple tasks at similar time. Limited by hardware and software resources. 6 Power of Remembering As long as exploiter desires, it can store any amount and type of information. Limited by hardware and software resources. No IQ Cannot make decisions until instructed. Cannot learn on its own. No Feelings No emotions, no taste, no knowledge. Instructions are required. 1. Evolution of Computers Necessity is the mother of invention and then who is the father? Curiosity, Vision, Idea 1642 Pascal invented first mechanical adding machine 1671 Baron Gottfried Wilhelm von Leibniz first calculator for multiplication 1880 Keyboards & Herman Hollerith used punch cards as input devices 19th century Charles Babbage, father of modern digital computer, Differential Engine, Analytical Engine 1. The Mark I Computer (1937-44) 2. The Atanasoff-Berry Computer (1939-42) 3. The ENIAC (1943-46) 4. The EDVAC (1946-52 5. The EDSAC (1947-49) . The UNIVAC I (1951) 1. 3 Computer Generations Overview of the major developments and technologies during the five generations of computers which include both hardware and software that together make up a computer system. 1. 3. 1 First Generation (1942-1955) utilize vacuum tubes(glass), performed calculations in milliseconds -Memory electromagnetic relays, Data & Instructions using Punch Card, Assembly Language schedule Characteristics Bulky in size, thousands of vacuum tubes, constant maintenance, costly, all circuits were man-made. . g. ENIAC, EDVAC, EDSAC, UNIVAC 1, and IBM 701 1. 3. 2 Second Generation (1955-1964) Used transistor, germanium semiconductor, magnetic disks and tape s, magnetic core memory faster, small in size, low cost, consume less power High level programming language like FORTRAN, COBOL, ALGOL, SNOBOL 1. 3. 3 Third Generation (1964-1975) -Integrated Circuits(IC) consists of transistors, resistors, capacitors, SSI(Small Scale Integration), MSI to a greater extent fast, performed one million instructions per second -low space, more reliable, less power consumption e. . Mini computers & mainframe computer computers 1. 3. 4 Fourth Generation (1975-1989) personal computer, IC- LSI, VLSI one million electronic components on a individual chip. Semiconductor memories less power, more fast, small in size Magnetic tapes, floppy disks, LAN, WAN, GUI, MS-DOS, Windows, Macintosh 1. 3. 5 Fifth Generation (1989-Present) VLSI & ULSI(Ultra Large Scale Integration) Microprocessor chips 10 millions electronic components Small, much faster, less power, portable, internet, www, email 1. 4 Block Diagram of Computer 1. 4. 1 Input Unit Accept data & I nstructions alter into digital form so that computer can accept and further bear upon can be done e. g. Mouse, Keyboard, Light Pen, Joystick, Scanner, Touch Screen 1. 4. 2 Storage Unit The reposition unit performs the pursual major functions All data and instructions are stored here before and after processing. Intermediate results of processing are also stored here. Primary Storage(Main Memory) This memory is generally used to hold the program being shortly executed in the computer, the data being received from the input unit, the intermediate and final results of the program. -Temporary in nature, i. e. inconstant memory -fast and cost is high than secondary storage -e. g. Random Access Memory(RAM) 2 Secondary Storage/ outside(a) Memory(Secondary Memory) Long term/ permanent storage of data. -slow and cost is low than primary memory -e. g.Floppy Disk(FDD),Hard disk drive(HDD), constrict Disk(CD), Digital Versatile/Video Disk, USB Drive, SDD 1. 4. 3 Memory size -Digital Computer uses the Binary System i. e. 0s and 1s severally character or a number is represented by an 8 bit code. -1 bit = either 0 or 1 4 bits= 1 nibble & 8 bits= 1 byte 1. 4. 4 turnout Unit Any peripheral devices that converts the stored binary coded data into convenient external forms as texts, pictures, sound e. g. Monitor, CD, Printer, Speaker, creative thinker phones, plotter, projector 1. 4. 5 Arithmetic Logical Unit All calculations(arithmetical +-x/ ), comparison(,=) and decisions Whenever calculations are required, the control unit transfers the data from storage unit to ALU once the computations are done, the results are transferred to the storage unit by the control unit and then it is send to the output unit for displaying results. 1. 4. 6 Control Unit -It controls all other units in the computer -The control unit instructs the input unit, where to store the data after receiving it from the user and how to output. It controls the flow of data and instructions(f etching of instructions from main memory and subsequent execution of these instructions) 1. 4. 7 Central Processing Unit 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. A PC may assume CPU-IC such as Intel 8085, 8086, 8088, 80286, 80386, 80486, Celeron, Pentium, Pentium Pro, Pentium II, Pentium III, Pentium IV, Dual Core, Core 2 Duo, Quad Core and AMD etc. 1. 5 abridgment