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Principles of Information Systems Eighth Edition. Chapter 3 Hardware: Input, Processing, and Output Devices. Principles and Learning Objectives.
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Principles of Information SystemsEighth Edition Chapter 3 Hardware: Input, Processing, and Output Devices
Principles and Learning Objectives • Assembling an effective, efficient set of computer hardware devices requires understanding their role in supporting the underlying information systems and the needs of the organization; the computer hardware objectives are subordinate to, but supportive of, the information systems and the needs of the organization • Describe how to select and organize computer hardware components to support information system (IS) objectives and business needs Principles of Information Systems, Eighth Edition
Principles and Learning Objectives (continued) • When selecting computer hardware, you must consider the current and future needs of the information systems and the organization; your choice of a hardware device should always allow for later improvements to meet evolving organizational needs • Describe the power, speed, and capacity of central processing and memory devices • Describe the access methods, capacity, and portability of secondary storage devices Principles of Information Systems, Eighth Edition
Principles and Learning Objectives (continued) • Discuss the speed, functionality, and importance of input and output devices • Identify popular classes of computer systems and discuss the role of each Principles of Information Systems, Eighth Edition
Why Learn About Hardware? • Can improve productivity, increase revenue, reduce costs, and provide better service • Managers are expected to know about hardware • To help define business needs • To ask questions and evaluate options when buying equipment Principles of Information Systems, Eighth Edition
Introduction • Hardware: any machinery (most of which use digital circuits) that assists in the input, processing, storage, and output activities of an information system • When making hardware decisions, businesses must consider how the hardware can support: • Objectives of the information system • Goals of the organization Principles of Information Systems, Eighth Edition
Computer Systems: Integrating The Power of Technology • Choosing the right computer hardware requires understanding its relationship to the information system and needs of the organization • Hardware objectives are subordinate to, but supportive of, the information system and the current and future needs of the organization Principles of Information Systems, Eighth Edition
Hardware Components • Central processing unit (CPU) • Input devices • Output devices Principles of Information Systems, Eighth Edition
Hardware Components (continued) • Communications devices • Primary storage devices • Secondary storage devices Principles of Information Systems, Eighth Edition
Hardware Components (continued) Figure 3.1: Hardware Components Principles of Information Systems, Eighth Edition
Hardware Components in Action • Step 1: Fetch instruction • Step 2: Decode instruction • Step 3: Execute instruction • Step 4: Store results Principles of Information Systems, Eighth Edition
Hardware Components in Action (continued) Figure 3.2: Execution of an Instruction Principles of Information Systems, Eighth Edition
Processing and Memory Devices: Power, Speed, and Capacity • System unit • Houses the components responsible for processing (the CPU and memory) • All other computer system devices are linked either directly or indirectly into the system unit housing Principles of Information Systems, Eighth Edition
Processing Characteristics and Functions • Machine cycle time is measured in: • Nanoseconds (1 billionth of a second) • Picoseconds (1 trillionth of a second) • MIPS (millions of instructions per second) Principles of Information Systems, Eighth Edition
Processing Characteristics and Functions (continued) • Clock speed: series of electronic pulses produced at a predetermined rate that affects machine cycle time • Often measured in: • Megahertz (MHz): millions of cycles per second • Gigahertz (GHz): billions of cycles per second • Microcode: predefined, elementary circuits and logical operations that the processor performs when it executes an instruction Principles of Information Systems, Eighth Edition
Physical Characteristics of the CPU • Digital circuits on chips • Electrical current flows through silicon • Moore’s Law: transistor density of chips will double every 18 months Principles of Information Systems, Eighth Edition
Physical Characteristics of the CPU (continued) Figure 3.3: Moore’s Law Principles of Information Systems, Eighth Edition
Memory Characteristics and Functions • Main memory • Located physically close to the CPU, but not on the CPU chip itself • Rapidly provides data and instructions to the CPU Principles of Information Systems, Eighth Edition
Storage Capacity Table 3.1: Computer Storage Units Principles of Information Systems, Eighth Edition
Types of Memory • Random access memory (RAM) • Temporary and volatile • Types of RAM • EDO (Extended Data Out) • DRAM (Dynamic RAM) • SDRAM (Synchronous DRAM) Principles of Information Systems, Eighth Edition
Types of Memory (continued) • Types of nonvolatile memory • ROM (read-only memory) • PROM (programmable read-only memory) • EPROM (erasable programmable read-only memory) • Cache memory: high-speed memory that a processor can access more rapidly than main memory Principles of Information Systems, Eighth Edition
Types of Memory (continued) Figure 3.4: Basic Types of Memory Chips Principles of Information Systems, Eighth Edition
Types of Memory (continued) Figure 3.5: Cache Memory Principles of Information Systems, Eighth Edition
Multiprocessing • Multiprocessing: simultaneous execution of two or more instructions at the same time • Multiprocessing using coprocessors • Coprocessor: speeds processing by executing specific types of instructions while the CPU works on another processing activity Principles of Information Systems, Eighth Edition
Parallel Computing • Parallel computing: simultaneous execution of the same task on multiple processors to obtain results faster • Massively parallel processing: • Speeds processing by linking hundreds or thousands of processors to operate at the same time, or in parallel • Each processor has its own bus, memory, disks, copy of the operating system, and applications Principles of Information Systems, Eighth Edition
Parallel Computing (continued) • Different approaches to achieving parallel computing • Single instruction/multiple data (SIMD) parallel processors • Multiple instruction/multiple data (MIMD) parallel processors • Grid computing: use of a collection of computers, often owned by multiple individuals or organizations, to work in a coordinated manner to solve a common problem Principles of Information Systems, Eighth Edition
Secondary Storage • Compared with memory, offers the advantages of nonvolatility, greater capacity, and greater economy • Access methods, storage capacities, and portability required are determined by the information system’s objectives Principles of Information Systems, Eighth Edition
Access Methods • Sequential access: records must be retrieved in order • Devices used are called sequential access storage devices (SASDs) • Direct access: records can be retrieved in any order • Devices used are called direct access storage devices (DASDs) Principles of Information Systems, Eighth Edition
Devices • Magnetic tapes • Magnetic disks • RAID • Virtual tape • Optical disks Principles of Information Systems, Eighth Edition
Devices (continued) • Digital video disk (DVD) • Holographic Versatile Disc (HVD) • Memory cards • Flash memory Principles of Information Systems, Eighth Edition
Enterprise Storage Options • Attached storage • Network-attached storage (NAS) • Storage area network (SAN) Principles of Information Systems, Eighth Edition
Enterprise Storage Options (continued) Figure 3.9: Storage Area Network Principles of Information Systems, Eighth Edition
Input and Output Devices: The Gateway to Computer Systems • Through input and output devices, people provide data and instructions to the computer and receive results from it • Selection of input and output devices depends on organizational goals and IS objectives Principles of Information Systems, Eighth Edition
Characteristics and Functionality • Data can be human-readable or machine-readable • Data entry: converts human-readable data into machine-readable form • Data input: transfers machine-readable data into system • Source data automation: capturing and editing data where the data is initially created and in a form that can be directly input to a computer Principles of Information Systems, Eighth Edition
Input Devices • Personal computer input devices • Keyboard • Mouse • Speech-recognition technology • Digital cameras • Terminals Principles of Information Systems, Eighth Edition
Input Devices (continued) • Scanning devices • Optical data readers • Magnetic ink character recognition (MICR) devices • Magnetic stripe card • Point-of-sale (POS) devices Principles of Information Systems, Eighth Edition
Input Devices (continued) • Automated teller machine (ATM) devices • Pen input devices • Touch-sensitive screens • Bar-code scanners • Radio Frequency Identification (RFID) Principles of Information Systems, Eighth Edition
Output Devices • Display monitors • Liquid crystal displays (LCDs) • Organic light-emitting diodes (OLEDs) • Printers and plotters • Digital audio player Principles of Information Systems, Eighth Edition
Special-Purpose Input and Output Devices • Computer-based navigation systems • Multiple function printers • Eyebud screens Principles of Information Systems, Eighth Edition
Computer System Types, Selection, and Upgrading • Special-purpose computers: used for limited applications by military and scientific research groups • General-purpose computers: used for a wide variety of applications Principles of Information Systems, Eighth Edition
Computer System Types • Handheld computers • Portable computers • Thin client • Desktop computers Principles of Information Systems, Eighth Edition
Computer System Types (continued) • Workstations • Servers • Mainframe computers • Supercomputers Principles of Information Systems, Eighth Edition
Selecting and Upgrading Computer Systems • Dispose of old equipment properly • Consider factors such as speed, cost, and performance when upgrading • Hard drive • Main memory • Printer • DVD burners Principles of Information Systems, Eighth Edition
Summary • Hardware: machinery that assists in the input, processing, storage, and output activities of an information system • Hardware components: central processing unit (CPU), input and output devices, communications devices, primary storage devices, and secondary storage devices • Random access memory (RAM): temporary and volatile • ROM (read-only memory): nonvolatile Principles of Information Systems, Eighth Edition
Summary (continued) • Multiprocessing: simultaneous execution of two or more instructions at the same time • Sequential access: records must be retrieved in order • Direct access: records can be retrieved in any order • Examples of secondary storage devices: magnetic tapes and disks, DVDs, memory cards, etc. • Enterprise storage options: attached storage, network-attached storage (NAS), and storage area network (SAN) Principles of Information Systems, Eighth Edition
Summary (continued) • Examples of input devices: keyboards, mice, voice-recognition devices, terminals, scanning devices, and touch-sensitive screens • Examples of output devices: display monitors, liquid crystal displays (LCDs), printers, and plotters • Computers can be classified as either special-purpose or general-purpose • Computer system types: handheld computers, portable computers, desktop computers, workstations, servers, etc. Principles of Information Systems, Eighth Edition