Computer Confluence 6/e Chapter 2 The Computer’s Core: The CPU and MemoryComputer Confluence 6/e Chapter 2 The Computer’s Core: The CPU and Memory (continued)Computer Confluence 6/e Chapter 2 CompatibilityComputer Confluence 6/e Chapter 2 PerformanceComputer Confluence 6/e Chapter 2 Performance (continued)Computer Confluence 6/e Chapter 2 The Computer’s MemoryComputer Confluence 6/e Chapter 2 The Computer’s Memory (continued)Computer Confluence 6/e Chapter 2 Buses, Ports, and PeripheralsComputer Confluence 6/e Chapter 2 Buses, Ports, and Peripherals (continued)Computer Confluence 6/e Chapter 2 Inventing the FutureComputer Confluence 6/e Chapter 2 Lesson SummaryComputer Confluence 6/e Chapter 2 Lesson Summary (continued)© 2005 Prentice-Hall, Inc. Slide 1Computer Confluence 6/e Chapter 2The Computer’s Core: The CPU and MemoryThe CPU: The Real ComputerCPU (microprocessor) Interprets and executes the instructions in each program Supervises arithmetic and logical data manipulations© 2005 Prentice-Hall, Inc. Slide 2Computer Confluence 6/e Chapter 2The Computer’s Core: The CPU and Memory (continued)Communicates with all the other parts of the computer system indirectly through memoryAn extraordinarily complex collection of electronic circuits Housed along with other chips and electronic components on the motherboard© 2005 Prentice-Hall, Inc. Slide 3Computer Confluence 6/e Chapter 2CompatibilityAll software is not necessarily compatible with every CPUSoftware written for the PowerPC family of processors used in Macintosh computers won’t run on Intel processorsPrograms written for Linux can’t run on WindowsBoth systems run on PCs powered by Intel’s microprocessor CPUs in the same family are generally designed to be backward compatible Newer processors can process all of the instructions handled by earlier models© 2005 Prentice-Hall, Inc. Slide 4Computer Confluence 6/e Chapter 2PerformanceApplications require faster machines to produce satisfactory resultsA computer’s overall performance isdetermined by:Its microprocessor’s internal clock speedMeasured in units called gigahertz (GHz)for billions of clock cycles per second The architecture and word size of the processorHigh-end workstations and servers use 64-bit processors Most PCs and Macintoshes use 32-bit processors Some embedded and special-purpose computers still use 8- and 16-bit processors© 2005 Prentice-Hall, Inc. Slide 5Computer Confluence 6/e Chapter 2Performance (continued)Techniques for speeding up a computer’s ability: Parallel processing Server clusters© 2005 Prentice-Hall, Inc. Slide 6Computer Confluence 6/e Chapter 2The Computer’s MemoryRAM (random access memory)Used to store program instructions and data temporarilyUnique addresses and data can be stored in any locationCan quickly retrieve information Will not remain if power goes off (volatile)© 2005 Prentice-Hall, Inc. Slide 7Computer Confluence 6/e Chapter 2The Computer’s Memory (continued)ROM (read-only memory) Information is stored permanently on a chipContains startup instructions and other permanent dataCMOS (complementary metal oxide semiconductor)Special low-energy kind of RAM Flash memory Used for phones, pagers, portable computers, handheld computers, PDAs© 2005 Prentice-Hall, Inc. Slide 8Computer Confluence 6/e Chapter 2Buses, Ports, and PeripheralsInformation travels between components on the motherboard through groups of wires called system buses, or just buses© 2005 Prentice-Hall, Inc. Slide 9Computer Confluence 6/e Chapter 2Buses, Ports, and Peripherals (continued)BusesTypically have 32 or 64 wires Connect to storage devices in baysConnect to expansion slotsConnect to external buses and portsSlots and ports Make it easy to add external devices, called peripherals© 2005 Prentice-Hall, Inc. Slide 10Computer Confluence 6/e Chapter 2Inventing the FutureNew laser etching technology called extreme ultraviolet lithography (EUVL) could reduce chip size and increase performance radically Superconductors that transmit electricity without heat could increase computer speed a hundredfold The optical computer transmits information in light waves rather than electrical pulses The only thing that has consistently grown faster than hardware in the last 40 years is human expectation.—Bjarne Stroustrup, AT&T Bell Labs, designer of the C++ programming language© 2005 Prentice-Hall, Inc. Slide 11Computer Confluence 6/e Chapter 2Lesson SummaryA computer manipulates patterns of bits—binary digits of information The CPU follows software instructions, reduced to strings of bits, to perform the calculations and logical manipulations that transform input data into output Not all CPUs are compatible with each other The great Information Age is really an explosion of non-information; it is an explosion of data. To deal with the increasing onslaught of data, it is imperative to distinguish between the two; information is that which leads to understanding.—Richard Saul Wurman, in Information Anxiety© 2005 Prentice-Hall, Inc. Slide 12Computer Confluence 6/e Chapter 2Lesson Summary (continued)The CPU uses: RAM (random access memory) as a temporary storage area—a scratch pad—for instructions and dataROM (read-only memory), which contains unchangeable information that serves as reference material for the CPU as it executes program instructionsThe CPU and main memory are housed in silicon chips on the