Chapter 1: Introduction1-1 CPSC-352 CPSC 352Computer OrganizationChapter 1: IntroductionChapter 1: Introduction1-2 CPSC-352Chapter Contents1.1 Overview1.2 A Brief History1.3 The Von Neumann Model1.4 The System Bus Model1.5 Levels of Machines1.6 Upward Compatibility1.7 The Levels1.8 A Typical Computer System1.9 Organization of the Book1.10 Case Study: What Happened to SupercomputersChapter 1: Introduction1-3 CPSC -352Some Definitions•Computer architecture deals with the functional behavior of acomputer system as viewed by a programmer (like the size of adata type – 32 bits to an integer).•Computer organization deals with structural relationships that arenot visible to the programmer (like clock frequency or the size ofthe physical memory).•There is a concept of levels in computer architecture. The basicidea is that there are many levels at which a computer can be con-sidered, from the highest level, where the user is running pro-grams, to the lowest level, consisting of transistors and wires.Chapter 1: Introduction1-4 CPSC -352Pascal’s Calculating Machine•Performs basic arithmetic operations (early to mid 1600’s). Doesnot have what may be considered the basic parts of a computer.•It would not be until the 1800’s until Babbage put the concepts ofmechanical control and mechanical calculation together into amachine that has the basic parts of a digital computer.(Source: IBMArchivesphotograph.)Chapter 1: Introduction1-5 CPSC -352Input UnitArithmetic and Logic Unit (ALU)Output UnitMemory UnitControl UnitThe von Neumann Model•The von Neumann model consists of five major components:(1) input unit; (2) output unit; (3) arithmetic logic unit; (4) memoryunit; (5) control unit.Chapter 1: Introduction1-6 CPSC -352System BusData BusAddress BusControl Bus(ALU, Registers,and Control)MemoryInput and Output (I/O)CPUThe System Bus Model•A refinement of the von Neumann model, the system bus modelhas a CPU (ALU and control), memory, and an input/output unit.•Communication among components is handled by a shared path-way called the system bus, which is made up of the data bus, theaddress bus, and the control bus. There is also a power bus, andsome architectures may also have a separate I/O bus.Chapter 1: Introduction1-7 CPSC -352High LevelHigh Level LanguagesUser Level: Application ProgramsLow LevelFunctional Units (Memory, ALU, etc.)Logic GatesTransistors and WiresAssembly Language / Machine CodeMicroprogrammed / Hardwired ControlLevels of Machines•There are a number of levels in a computer (the exact number isopen to debate), from the user level down to the transistor level.•Progressing from the top level downward, the levels become lessabstract as more of the internal structure of the computer be-comes visible.Chapter 1: Introduction1-8 CPSC -352MonitorCD-ROM driveHard disk driveKeyboardSockets for internal memoryCPU (Microprocessor beneath heat sink)Sockets for plug-in expansion cardsDiskette driveA Typical Computer SystemChapter 1: Introduction1-9 CPSC -352MemoryInput / outputBatteryPlug-in expansion card slotsPower supply connectorPentium II processor slot (ALU/control)The Motherboard•The five von Neumann components are visible in this examplemotherboard, in the context of the system bus model.(Source: TYAN Computer,http://www.tyan.com)Chapter 1: Introduction1-10 CPSC -352Manchester University Mark I•Supercomputers, which are produced in low volume and have ahigh price, have been largely displaced by, high-volume low-priced machines that offer a better price-to-performance ratio.(Source: http://www.paralogos.com/DeadSuper)Chapter 1: Introduction1-11 CPSC -352Moore’s Law•Computing power doubles every 18 months for the same price.•Project planning needs to take this observation seriously: an ar-chitectural innovation that is being developed for a projected ben-efit that quadruples performance in three years may no longer berelevant: the architectures that exist by then may already offerquadrupled performance and may look entirely different fromwhat the innovation needs to be