Powered by DeSiaMore3 Our Agenda Computer Organization Input and Output Devices Primary Storage The Central Processing Unit Secondary Storage
Powered by DeSiaMore4 Learning Objectives Describe the main components of the computer. List common input and output devices Describe how is data represented in a computer? Describe how primary storage is organized.
Powered by DeSiaMore5 Learning Objectives (contd.) Describe the structure and function of the central processing unit (CPU). Describe how is data stored and retrieved using common forms of secondary storage?
Powered by DeSiaMore6 Computer Organization Information System Hardware
Powered by DeSiaMore7 What is a computer A computer is a device that is 1.Electronic 2.Can store data 3.Can store and follow a set of software instructions, called a program.
Powered by DeSiaMore8 Input Devices An input device accepts data from outside the computer and converts it into an electronic form the computer can understand. Examples include a keyboard, mouse, scanner, digital pen, and digital tablet.
Powered by DeSiaMore9 Output Devices An output device converts data from an electronic form inside the computer to a form that can be used outside the computer. Examples include a screen, monitor, printer, and fax.
Powered by DeSiaMore10 Primary Storage Primary storage, also called internal storage, is the memory, or RAM, of the computer. Primary storage, which is temporary storage, is dependent upon continuous electrical power. Any interruption of electrical power causes the contents of primary storage to be lost.
Powered by DeSiaMore11 Central Processing Unit (CPU) The CPU, or processor, carries out the instructions of the program. It contains circuits that perform arithmetic and logical operations. Data is transferred from primary storage to the CPU with the results sent back to primary storage.
Powered by DeSiaMore12 Secondary Storage Secondary storage, also called auxiliary storage, stores data not currently being processed by the computer and represents permanent storage. Data is usually transferred to and from primary storage. Examples include hard disks, floppy disks, ZIP disks, CDROMs, and DVDs.
Powered by DeSiaMore13 Input and Output Devices Information System Hardware
Powered by DeSiaMore14 Keyboards Most widely used input device. Possible physical problems include Repetitive strain injuries Carpal tunnel syndrome Ergonomically designed keyboards may improve user comfort and efficiency and reduce risk of injury.
Powered by DeSiaMore15 Pointing Devices Mouse Trackball Trackpoint Trackpad, also called a touchpad Cursor
Powered by DeSiaMore16 Other input devices Touch screen Pen input Graphics tablet Digitizer tablet Light pen
Powered by DeSiaMore17 Optical Scanning Input Devices Bar-code scanner Universal Product Code (UPC) Flat bed, or page scanner Automatic document feeder (ADF) scanner Optical Character Recognition (OCR) Mark-sense readers
Powered by DeSiaMore18 Magnetic Scanning Input Devices Magnetic strip reader Credit cards ID Cards Magnetic Ink Character Recognition (MICR) – used at the bottom of all checks by the banking industry.
Powered by DeSiaMore19 Voice Input Devices Voice recognition software Dragon Naturally Speaking Via-Voice Uses a microphone connected to the computer and translates the spoken word to text output.
Powered by DeSiaMore20 Digital Input Devices Digital cameras that produce photographic quality images. Cameras connected to the computer for live images.
Powered by DeSiaMore21 Screens, or Monitor, or CRT Key elements of a screen include: Pixels – picture elements arranged as a pattern of dots. Screen resolution – the number of pixels that can be displayed on a screen at one time. Refresh rate – the number of times per second that screen repaints itself.
Powered by DeSiaMore22 Screens, or Monitor, or CRT (contd.) Types of monitors Traditional tube monitors, or cathode ray tube (CRT). Flat-panel screens – most common type is liquid crystal display (LCD). Screen projector used to display a computers output on a large screen.
Powered by DeSiaMore23 Printers Printer classifications Impact printer Nonimpact printer Serial printers Line printers Page printers Letter-quality printers Draft-quality printers
Powered by DeSiaMore24 Desktop printers Ink-jet, or bubble-jet printer Typically 200 to 300 characters per second Laser printers Typically between 4 and 24 pages per minute. Dot matrix printer Typically between 200 and 300 characters per second.
Powered by DeSiaMore25 High volume printers Line printers High end line printers can print as much as 3,600 lines per minute (at 60 lines per page, that is 60 page per minute) and can cost $50,000. Page printers High end page printers can print as much as 200 pages per minute and can cost $100,000.
Powered by DeSiaMore26 Other Output Devices Plotters Voice output devices – converting digitized data into synthesized speech Sound output devices – speakers Specialized devices for people with disabilities – can include large typeface screens, Braille display devices, special pointing devices, or headphones.
Powered by DeSiaMore27 Virtual Reality Virtual reality is the use of a computer to produce realistic images and sounds in such a way that the user senses that he or she is a part of the scene. Examples include architectural design, home remodeling, aircraft design, machine design, and more.
Powered by DeSiaMore28 Primary Storage Information System Hardware
Powered by DeSiaMore29 Primary Storage Structure Input data is stored in primary storage (memory) after it is received from an input device. Output data is stored in primary storage before it is sent to an output device. Without sufficient primary storage, it may not be possible to execute certain programs or use certain data.
Powered by DeSiaMore30 Primary Storage Structure (contd.) Silicon chips – integrated circuits Volatile storage – dependent upon continuous power Random Access Memory (RAM) Non-volatile storage Read-Only Memory (ROM)
Powered by DeSiaMore31 Primary Storage Structure (contd.) Binary representation A combination of positive and negative electrical charges, represented by 1s and 0s when written to represent a character. One charge is called a bit. Eight bits are required to represent a single character, called a byte. The 256 possible (2 8 ) binary combinations are defined in character set.
Powered by DeSiaMore32 Primary Storage Structure (contd.) Personal computer character set ASCII – American Standard Code for Information Interchange Mainframe computer character set EBCDIC – Extended Binary Coded Decimal Interchange Code Though each contains 256 characters, the definitions are not the same, so a translator is required for one machine type to talk with the other machine type.
Powered by DeSiaMore33 Primary Storage Structure (contd.) Storage locations of the bytes are called allocation units each of which has a unique address. Storage capacities Kilobyte (KB) or 1024 bytes (2 10 ) – approximately 1,000 bytes, thus the kilo Megabyte (MB) or 1,048,756 bytes (2 20 ) Gigabyte (GB) or 1,073,741,824 bytes (2 30 ) Terabyte (TB) or 1,099,511,627,776 bytes (2 40 )
Powered by DeSiaMore34 The Central Processing Unit Information System Hardware
Powered by DeSiaMore35 Two Main Parts of a CPU Arithmetic-Logic Unit (ALU) May add, subtract, multiply and divide two numbers. More complex operations are are completed by using sequences of the four basic operations. Control Unit Analyzes and executes instructions in a program. Instructions are brought in one at a time from primary storage.
Powered by DeSiaMore36 CPU Speed Early CPUs processed 8 or 16 bits at a time. Current CPUs process 32 bits, and some can process 64 or 128 bits at a time. The roadway from primary storage to the CPU is the bus. Higher bus capacities mean faster computers.
Powered by DeSiaMore37 CPU Speed (contd.) Clock speed Measured in megahertz (MHz) or gigahertz (GHz). One MHz is one million cycles per second. One GHz is one billion cycles per second. Earliest IBM PCs ran at 4.77 MHz. Current PCs run at or above 1,000 MHz (1 GHz).
Powered by DeSiaMore38 Common CPUs Microcomputer Intel 4004 Intel 8088 Intel 8086 Intel 80286 Intel 80386 Intel 80486 Intel Pentium Intel Pentium Pro Intel Pentium II Intel Pentium III Apple/Macintosh Motorola 68000 Motorola 68020 Motorola 68030 Motorola 68040 Motorola Power PC G3 AMD
Powered by DeSiaMore39 Common CPUs (contd.) Minicomputer and Mainframe Developed by the manufacturer within a line of products HP3000 IBM System/390 DEC Alpha Supercomputers Generally specific to a single product
Powered by DeSiaMore40 Secondary Storage Information System Hardware
Powered by DeSiaMore41 Types of Secondary Storage Magnetic Disk Storage Floppy disk Hard disk ZIP disk Disk organization Disk Head (or side) Track Allocation Unit
Powered by DeSiaMore42 Optical Disk Storage Compact disks (CDROMs) Capacity of approximately 600MB Writable Compact Disks (CD-RWs) Capacity of approximately 600MB Digital Video Disks or Digital Versatile Disks (DVDs) Capacity of approximately 4.7GB to 17GB depending on how it is used.
Powered by DeSiaMore43 Magnetic Tape Storage Magnetic tape has a capacity of 200MB to over 40GB. Data transferred to the tape via a magnetic tape drive. Data on a tape can only be read sequentially.
Powered by DeSiaMore44 Information Systems Hardware Key Terms
Powered by DeSiaMore45 Key Terms Address Arithmetic-Logic-Unit (ALU) ASCII Backup Copy Bar-Code Scanner Binary Digit (Bit) Byte CD-R/CD-ROM/CD-RW Central Processing Unit (CPU) Chip Compact Disk Computer Control Unit VRT Cursor Disk Pack
Powered by DeSiaMore46 Key Terms (contd.) Dot-Matrix Printer Draft-Quality Printer DVD/DVD-ROM EBCDIC Ergonomics Flat Panel Screen Floppy Disk Gigabyte (GB) Gigahertz (GHz) Hard Disk Impact Printer Input Device Ink-Jet Printer Keyboard Kilobyte (KB) Laser Printer Letter-Quality Printer Line Printer
Powered by DeSiaMore47 Key Terms (contd.) Machine Language Magnetic Disk Magnetic Disk Drive Magnetic Ink Character Recognition (MICR) Magnetic Strip Reader Magnetic Tape Magnetic Tape Drive Massively Parallel Processing Megabyte (MB) Megahertz (MHz) Microprocessor Microsecond Millisecond Monitor Mouse
Powered by DeSiaMore48 Key Terms (contd.) Multifunction Printer Multimedia Multiprocessing Nanosecond Nonimpact Printer Nonvolatile Storage Optical Disk Optical Disk Drive Output Device Page Printer Parity Bit Pen Input Peripheral Equipment Pixel Plotter Primary (Internal) Storage Printer
Powered by DeSiaMore49 Key Terms (contd.) Processor Program RAID Random Access Memory (RAM) Random (Direct) Access Read Only Memory (ROM) Scanner Screen Screen Projector Screen Resolution Secondary (Auxiliary) Storage Sequential Access Serial Printer Storage Location Terabyte (TB)