1 / 38

COMPUTER APPLICATIONS

COMPUTER APPLICATIONS THE CPU AND MEMORY COM 6 THE SYSTEM UNIT Common Components Processor (CPU) Interprets and carries out the basic instructions that operate a computer Memory module Houses the memory that temporarily holds data and instructions while they are being processed by the CPU

Gideon
Télécharger la présentation

COMPUTER APPLICATIONS

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. COMPUTER APPLICATIONS THE CPU AND MEMORY COM 6

  2. THE SYSTEM UNIT Common Components • Processor (CPU) • Interprets and carries out the basic instructions that operate a computer • Memory module • Houses the memory that temporarily holds data and instructions while they are being processed by the CPU • Expansion cards • Circuit board that adds devices or capabilities • Ex. Sound, modem, and video cards • Ports • Connectors

  3. Ports & Connectors Processor Sound, Modem, & Video Cards Memory Module

  4. THE SYSTEM UNIT • The Motherboard (aka System Board) • Contains many of the electronic components • Chips • A small piece of semiconducting material on which one or more integrated circuits are etched • (1) of the most important chips: CPU

  5. Motherboard Chips

  6. CPU AND MICROPROCESSOR • CPU (processor) • Interprets and carries out the basic instructions that operate a computer • Microprocessor - contains the CPU on a single chip in a PC • Ex. Pentium, Celeron, Athlon

  7. CPU AND MICROPROCESSOR • The Control Unit • A component of the CPU that directs and coordinates most of the operations in the computer • (4) Steps in Machine Cycle(aka Instruction Cycle) • Fetch - get the next instruction or data item from memory • Decode - translate the instruction • Execute - carry out the command • Store - write the result to memory • Speed - # of instructions processed per second • Measured in MIPS (Million Instructions Per Second) • Refers to CPU speed only

  8. Most of the devices connected to the computer communicate with the CPU in order to carry out a task. The arrows in this figure represent the flow of data, instructions, and information.

  9. The Machine Cycle:

  10. CPU AND MICROPROCESSOR • The Arithmetic/Logic Unit (aka ALU) • Performs the execution part of the machine cycle: • Arithmetic Operations (addition, subtraction, multiplication, division) • Comparison Operations (greater than, equal to, less than) • Logical Operations (AND, OR, NOT)

  11. CPU AND MICROPROCESSOR • Pipelining • The CPU begins execution of a second instruction before the first instruction is completed • Results in faster processing because the CPU does not have to wait for (1) instruction to complete the machine cycle before fetching the next • See Next Slide…

  12. CPU AND MICROPROCESSOR • Registers • Temporary storage locations used by the CPU • Holds data and instructions • Many types • Storing location of where instruction was fetched • Storing an instruction while it is being decoded • Storing data while the ALU processes it • Storing the results of a calculation

  13. CPU AND MICROPROCESSOR • The System Clock • Synchronizes all computer operations • Each tick is called a clock cycle • Faster clock means more instructions the CPU can execute each second • Speed measured in • Megahertz (MHz) = 1 million ticks of the system clock • Gigahertz (GHz) = 1 billion ticks of the system clock • Ex. 600 MHz has 600 million clock cycles per second • Speed ONLY affects the CPU & not the peripherals

  14. CPU AND MICROPROCESSOR • Microprocessor Comparison • Intel Pentium • Intel Celeron – for less expensive PCs • AMD (Intel-compatible) • Motorola PowerPC – found in Apple computers • Alpha – used primarily in workstations & high-end servers

  15. CPU AND MICROPROCESSOR • Microprocessor Comparison • Types of Intel processors: • Xeon • Pentium II with MMX • MMX allows the computer to manipulate and process multimedia data more efficiently • Celeron **Higher clock speed means faster processor and costs more $$ • See next slide for comparisons

  16. CPU AND MICROPROCESSOR • Processor Installation and Upgrades • Processor chips – inserted on motherboard • Zero-insertion force (ZIF) sockets – facilitate the installation & removal of processor chips • Upgrades: • Chip for chip – replace existing chip with a new one • Piggyback – new chip is stacked on top of the old one • Daughterboard – new chip is located on the daughterboard (small circuit board that plugs into the motherboard to add additional capabilities)

  17. CPU AND MICROPROCESSOR • Heat Sinks and Heat Pipes • Heat sink • Small ceramic or metal component with fins on its surface that is designed to absorb and ventilate heat produced by electrical components • Heat pipe • Like a heat sink, but used in laptops because there isn’t as much room as in a PC

  18. CPU AND MICROPROCESSOR • Coprocessors • Increases computer performance • Special processor chip or circuit board designed to assist the processor in performing specific tasks • Floating-point coprocessor (aka math or numeric coprocessors) • Beneficial in engineering, scientific, or graphics applications

  19. CPU AND MICROPROCESSOR • Parallel Processing • Using multiple processors simultaneously to execute a program • Speeds execution of the problem • Requires special software designed to recognize how to divide up the problem and then bring the results back together again • Ex. Supercomputers use it for weather forecasting

  20. Parallel processing divides up a problem so that multiple processors work on their assigned portion of a problem at the same time.

  21. DATA REPRESENTATION • Analog (human speech) vs. Digital • Digital • Only understand two states (On and Off) • Binary number system • Combination of ones and zeroes represent characters • Bit – smallest unit of data a computer can handle; is each on or off digital value • 8 bits = 1 byte

  22. DATA REPRESENTATION • ASCII (American Standard Code for Information Interchange)vs. EBCDIC (Extended Binary Coded Decimal Interchange Code) • Both are sufficient for English and Western European languages • Unicode often used for other languages • Sending a character from the keyboard to the computer - Press key on keyboard computer converts it to binary & stores it  after processing, converts binary code back to an image image displayed on screen

  23. ASCII & EBCDIC Coding Schemes

  24. MEMORY • Used to store data, instructions, and information • Stores (3) basic items: • The operating system and other system software • Application programs • Data being processed by application programs • Bytes – the basic storage unit • Are stored at specific locations or addresses

  25. Seats in a stadium are like addresses in memory… • Both: • Hold only (1) person/byte at a time • Can be empty • Have a unique identifying number

  26. MEMORY • Size of memory is measured by the number of bytes available • Kilobyte (KB or K) - 1,024 bytes • Megabyte (MB) - one million bytes • Two memory types: • Volatile - contents lost when power is off; ex. RAM • Nonvolatile - not lost when power is off; ex. ROM

  27. MEMORY • RAM (Random Access Memory) • Are the memory chips in the system unit • When the computer starts, operating system files are loaded from a hard disk into RAM • Information stays in RAM while computer is running • RAM Types: • Dynamic RAM (DRAM) • Must be re-energized constantly or it loses its contents • Synchronous DRAM (SDRAM) – much faster than DRAM because it’s synchronized to the system clock • Static RAM (SRAM) • Faster and more reliable than any DRAM • Doesn’t have to be re-energized as often as DRAM • More expensive than DRAM

  28. MEMORY • RAM Chips • Smaller in size than processor chips • Packaged on circuit boards called single inline memory modules (SIMMs) or dual inline memory modules (DIMMs) • Found on the motherboard

  29. MEMORY • Configuring RAM • The more RAM, the more programs and files a computer can work on at once • Software usually tells you how much RAM is required • Amount of RAM needed depends on what type of work the computer is used for • Amount of RAM determines how many programs & how much data a computer can handle

  30. MEMORY • Cache • Helps speed the processing time of the computer by storing frequently used instructions and data • Most modern computers have two types of cache: • Level 1 - small capacity (8-64KB); built into processor chip • Level 2 - larger capacity (64KB-2MB), but slower; not part of the processor chip • When the processor needs an instruction, it searches memory in this order: • L1 Cache L2 cache  RAM

  31. More Cache = More Speed L2 Cache

  32. MEMORY • ROM (Read-only memory) • Cannot be modified • Contents not lost when the computer is turned off (Nonvolatile memory) • Contain data, instructions, or information that is recorded permanently • Programmable read-only memory (PROM) – program once and then it’s permanently on the chip • Flash Memory – can be erased and re-programmed

  33. MEMORY • CMOS • Complementary metal-oxide semiconductor • Another type of memory chip in the system unit • Stores configuration information about the computer such as type of disk drives, keyboard, and monitor • Uses a battery to retain the information when the computer is turned off • Keeps the calendar, date, and time current when computer is off • Information can be changed – unlike ROM

  34. MEMORY • Memory Access Times • Access Time - Speed at which the processor can access data from memory directly • Measured in fractions of a second • Measured in nanoseconds (ns) which is one billionth of a second Ten million operations in one blink

More Related