Chapter 2 - CC1 -.pptx

15th Edition Understanding Computers Today and Tomorrow Comprehensive Chapter 2 The Systems...

15th Edition Understanding Computers Today and Tomorrow Comprehensive Chapter 2 The Systems Unit: Processing and Memory Deborah Morley Charles S. Copyright 2015 Cengage Learning  Learning Objectives 1. Understand how data and programs are represented to a computer and be able to identify a few of the coding systems used to accomplish this. 2. Explain the functions of the hardware components commonly found inside the system unit, such as the CPU, GPU, memory, buses, and expansion cards. 3. Describe how peripheral devices or other hardware can be added to a computer. 4. Understand how a computer’s CPU and memory components process program instructions and data. Understanding Computers: Today and Tomorrow, 15th 2 Edition  Learning Objectives 5. Name and evaluate several strategies that can be used today for speeding up the operations of a computer. 6. List some processing technologies that may be used in future computers. Understanding Computers: Today and Tomorrow, 15th 3 Edition  Overview Explain how computers represent data and program instructions. Explain how the CPU and memory are arranged with other components inside the system unit. Explain how a CPU performs processing tasks. Identify strategies that can be used today to create faster and better computers in the future. Understanding Computers: Today and Tomorrow, 15th 4 Edition  Data and Program Representation Digital Data Representation – Coding Systems Used to represent data and programs in a manner understood by the computer – Digital Computers Can only understand two states, off and on (0 and 1) – Digital Data Representation The process of representing data in Edition digital form so it can be Understanding Computers: Today and Tomorrow, 15th 5  Digital Data Representation – Bit The smallest unit of data that a binary computer can recognize (a single 1 or 0) – Byte = 8 bits Byte terminology used to express the size of documents and other files, programs, etc. – Prefixes are often used to express larger quantities of bytes: kilobyte (KB), megabyte (MB), gigabyte (GB), terabyte (TB), petabyte (PB), exabyte (EB), zettabyte (ZB), yottabyte Understanding Computers: Today and Tomorrow, 15th Edition (YB). 6  Representing Numerical Data The Binary Numbering System – Numbering system A way of representing numbers – Decimal numbering system Uses 10 symbols (0-9) – Binary numbering system Uses only two symbols (1 and 0) to represent all possible numbers – In both systems, the position of the digits determines the power to which the base number (such Understanding Computers: Today and Tomorrow, 15th 7 Edition as 10 or 2) is raised  Representing Numerical Data Understanding Computers: Today and Tomorrow, 15th 8 Edition  Coding Systems for Text-Based Data ASCII (American Standard Code for Information Interchange) – Coding system traditionally used with personal computers EBCDIC (Extended Binary-Coded Decimal Interchange Code) – Developed by IBM, primarily for mainframes Understanding Computers: Today and Tomorrow, 15th 9 Edition  Coding Systems for Text-Based Data Unicode – Newer code (32 bits per character is common) – Universal coding standard designed to represent text- based data written in any ancient or modern language – Replacing ASCII as the primary text-coding system Understanding Computers: Today and Tomorrow, 15th 10 Edition  Coding Systems for Other Types of Data Graphics Data (still images such as photos or drawings) – Bitmapped images Image made of up of a grid of small dots called pixels Monochrome graphic can only be one of two colors – Requires just one bit for color storage Images with more than two colors – Can use 4, 8, or 24 bits to store the color data for each pixel – More bits = more colors Understanding Computers: Today and Tomorrow, 15th 12 Edition  Coding Systems for Other Types of Data Understanding Computers: Today and Tomorrow, 15th 13 Edition  Coding Systems for Other Types of Data Audio Data – Must be in digital form in order to be stored on or processed by a computer – Often compressed when sent over the Internet MP3 files are 10 times smaller than their uncompressed digital versions Download more quickly and take up less storage space Video Data – Displayed using a collection of frames, each frame contains a still image – Amount of data can be substantial, but can be Understanding Computers: Today and Tomorrow, 15th Edition compressed 14  Representing Software Programs Machine language – Binary-based language for representing computer programs the computer can execute directly – Early programs were written in machine language – Today’s programs still need to be translated into machine language in order to be understood by the computer Understanding Computers: Today and Tomorrow, 15th 15 Edition  Inside the System Unit System Unit – The main case of a computer – Houses the processing hardware for a computer – Also contains storage devices, the power supply, and cooling fans – Houses processor, memory, interfaces to connect to peripheral devices (printers, etc), and other components – With a desktop computer, usually looks like a rectangular box Understanding Computers: Today and Tomorrow, 15th 16 Edition  Inside the System Unit Understanding Computers: Today and Tomorrow, 15th 17 Edition Motherboard  Inside the System Unit The Motherboard – Computer Chip Very small pieces of silicon or other semi- conducti ng material onto Understanding Computers: Today and Tomorrow, 15th 19 Edition which  Inside the System Unit External devices (monitors, keyboards, mice, printers) Wireless devices (e.g., Bluetooth) Power Supply – Connects to the motherboard to deliver electricity (personal computer) – Portable computers use rechargeable battery pack Nonremovable batteries more difficult and expensive to replace Understanding Computers: Today and Tomorrow, 15th 20 Edition  Inside the System Unit Drive Bays – Rectangular metal racks inside the system unit that house storage devices Hard drive, CD/DVD drive, flash memory card reader Connected to the motherboard with a cable Processors – The CPU (Central Processing Unit) Circuitry and components packaged together and connected directly to the motherboard Does the vast majority of processing for a computer Also called a processor; called a microprocessor when talking about personal computers Understanding Computers: Today and Tomorrow, 15th 21 Edition  Inside the System Unit – Dual-core CPU Contains the processing components (cores) of two separate processors on a single CPU – Quad-core CPU Contains four cores – Multi-core processors allow computers to work on more than one task at a time – Typically different CPUs for desktop computers, portable computers, servers, mobile devices, consumer devices, etc. Personal computer CPU often made by Intel or AMD Edition Understanding Media tablets and mobile phones use Computers: Today and Tomorrow, 15th 22  Inside the System Unit Understanding Computers: Today and Tomorrow, 15th 23 Edition  Inside the System Unit – The GPU (graphics processing unit) Takes care of the processing needed to display images (including still images, animations) on the screen Can be located on the motherboard, on a video graphics board, on in the CPU package Understanding Computers: Today and Tomorrow, 15th 24 Edition  Inside the System Unit Processing Speed – CPU clock speed is one measurement of processing speed – Rated in megahertz (MHz) or gigahertz (GHz) – Higher CPU clock speed = more instructions processed per second – Alternate measure of processing speed is the number of instructions a CPU can process per second Megaflops (millions), gigaflops (billions), teraflops (trillions) – Benchmark tests can be used to Edition evaluate overall processing speed Understanding Computers: Today and Tomorrow, 15th 25  Inside the System Unit Word Size – The amount of data that a CPU can manipulate at one time – Typically 32 or 64 bits Cache Memory – Special group of very fast memory chips located on or close to the CPU – Level 1 is fastest, then Level 2, then Level 3 – More cache memory typically means faster processing – Usually internal cache (built into the CPU) Understanding Computers: Today and Tomorrow, 15th 26 Edition  Inside the System Unit Bus Width, Bus Speed, and Bandwidth – A bus is an electronic path over which data can travel – Found inside the CPU and on the motherboard – Bus width is the number of wires in the bus over which data can travel A wider bus allows more data to be transferred at one time Understanding Computers: Today and Tomorrow, 15th 27 Edition  Inside the System Unit Bus width and speed determine the throughput or bandwidth of the bus – The amount of data that can be transferred by the bus in a given time period Understanding Computers: Today and Tomorrow, 15th 28 Edition  Memory Memory – Refers to chip-based storage located inside the system unit – Storage refers to the amount of long-term storage available to a computer – Random Access Memory (RAM) Computer’s main memory Consists of chips arranged on a circuit board called a memory module which are plugged into the motherboard Stores essential parts of operating system, Edition programs, and data the computer is Understanding Computers: Today and Tomorrow, 15th 29  Memory Understanding Computers: Today and Tomorrow, 15th 30 Edition