ICS 2101 Introduction- to- computer 2 PDF

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ICS 2101 Introduction- to- computer 2
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ICS 2101: COMPUTER ORGANIZATION Course Outline: 1. Classification of computers according to generation and size Super, main frame, micro and mini 2. Fundamentals of PCs: Hardware devices i. Mother board ii. Bus iii. Power supply iv. Input and output devices; v. Primary devices vi. Secondary storage devices 3. Processor architectures: i. Von Neumann and Non-Von Neumann architecture, ii. Reduced Instruction Set Computers (RISC), iii. Complex Instruction Set Computers (CISC), iv. Superscalar 4. Addressing modes 5. Instruction set 6. Memories Types and classification i.

Random access memory (RAM),

ii.

Read only memory (ROM),

iii.

Cache memory,

iv.

Virtual memory and

v.

Secondary memory (HDD vs SDD hard disk technologies) and the shift from IDE technology and SATA technology

Teaching and Learning Methodology: Lectures,

tutorials,

practical

sessions

in

Computer

Laboratory,

class

discussions,

individual/group projects. Instructional Materials/Equipment: Whiteboards/smart boards, whiteboard markers, duster, computers, projector, other computer laboratory resources, and hand-outs. Course Assessment Procedures: Continuous Assessment Tests (15%), Practicals (10%), Assignments (5%) and End-of-Semester Examination (70%). Course Textbooks: 1. Capron, H. L. & Johnson, J. A (2003), Computers: Tools for an Information Age, 8th ed., Prentice Hall, ISBN-10: 0131405640, ISBN-13: 978-0131405646. 2. John L. Hennessy & David A. Patterson (2007), Computer Architecture: A quantitative Approach, 4th ed., Morgan Kaufmann-Elsevier, ISBN-13:978-0123838728 3. Norton, P. (2006), Introduction to Computers, 6th ed., McGraw-Hill Technology Education, ISBN: 0072978902. 4. William Stalling (2001), Computer Organization and Architecture, 5th ed., Pearson Education, ISBN-13: 978-0130812940. Reference Textbooks: 1. David A. Patterson & John L. Hennessy (2013), Computer Organization and Design: The Hardware/Software Interface, 3rd ed., Morgan Kaufmann, ISBN-13:978-0124077263. 2. John D. Carpinelli (2000), Computer Systems Organization and Architecture, Addison Wesley, ISBN-10: 0201612534.

3. French, C. S. (1996), Computer Science, 5th ed., Thomson Learning, ISBN-13: 9780826454607, ISBN-10: 0826454607. 4. Karthikeyan, K. S. (2008), Guide to Computer Science, Sura Books, ISBN-10: 8184490453, ISBN-13: 9788184490459. Course Journals: 1. ACM Sigarch Computer Architecture News, ISSN: 0163-5964. 2. IEEE Transactions on Very Large Scale Integration Systems, ISSN: 1063-8210. Reference Journals: 1. Journal of Systems Architecture, ISSN: 1383-7621. 2. International Journal of Scientific Research and Management, ISSN: 2321-3418. 3. International Journal of Engineering and Computer Science, ISSN: 2319-7242.

CLASSIFICATION OF COMPUTERS Classification by generation and size Generations of Computers 1stGeneration 1945 - 1956 First generation of computers was constructed from vacuum tubes, relays, switches, crystal diodes and passive components. Drum memory was used for program storage. The typical example of the first generation computer was ENIAC (Electronic Numerical Integrator And Computer) computer mentioned earlier. Its technical parameters were: Up to 18,000 vacuum tubes and 7,200 crystal diodes, 70,000 resistors, 10,000 capacitors and inductors,1,500 relays, 6,000 switches and 5 million hand-soldered joints, Weight of 30 tonnes, power consumption of up to 200kW, Performance of up to 5,000 operations per second, Programmed in machine code, to change a program one week was required. 2ndGeneration 1956 - 1965 The replacement of vacuum tubes by transistors is characteristic for the second generation of computers. The transistor is a semiconductor invented in Bell Labs in 1947. Transistors allow computers to become smaller, faster, cheaper, more energy-efficient and more reliable than their first-generation predecessors.

Magnetic drum memory was replaced by magnetic ferrite core memories technology. Up to16kB of core memory available. Program was read from punched card or tape, output printed. Magnetic tapes and discs were used as external memory. Programming moved from cryptic binary machine language to symbolic language or early version of FORTRAN and COBOL. First operating system was developed, batch processing used. 3rdGeneration 1965 - 1980 The usage of integrated circuit with small and medium scale integration is typical for the 3rdgeneration of computers. Miniaturized transistors on silicon drastically increased the speed and efficiency of computers. Fixed discs were used to save program from punched cards. Spooling – parallel I/O operation during process execution. First memory made from IC – higher capacity and speed. Multiprogramming to run more jobs at the same time. Timesharing to allow multi-users access to computer at the same time with keyboard and CRT monitors. Complex OS such as OS/360 (developed by IBM) were used. Used for various applications including scientific and business applications. First minicomputer was introduced. 4th Generation 1980 … The fourth generation of computer is characterized by VLSI IC usage. Computers were smaller, mainframes turned into workstations and desktops. Speed and efficiency is still growing up. Thousands of ICs were integrated to one silicon chip. First single chip CPUs (ALU with Control Unit) were developed. Semiconductor memory DRAM and SRAM were used as the main computer memory. Secondary memory was composed of hard discs and floppies. Multiuser OS with GUI, network OS, distributed OS developed. Parallelism, pipelining cache memory and virtual memory were applied in a better way.

Many new programming languages (C, Pascal,…).Color CRT monitors, keyboard and mouse. Beyond the 4th generation (1985 – Till date) E-commerce, E-banking, home office ARM, AMD, INTEL, MOTOROLA High speed processor – GHz speed Because of submicron IC technology lot of added features in small size The following classification is in order of decreasing power and size. Microcomputer They represent a further step in miniaturization in which the various integrated circuits and elements of a computer are replaced by a single integrated circuit called a “chip” Minicomputer Physically smaller computers compared with mainframes. They are used for special purposes or smaller scale general purpose work. Mainframe Mainframe is a very large in size and an expensive computer capable of supporting hundreds, or even thousands, of users simultaneously. Mainframe executes many programs concurrently. Mainframes support many simultaneous programs execution. Supercomputer Supercomputers are one of the fastest computers currently available. Supercomputers are very expensive and are employed for specialized applications that require immense amounts of mathematical calculations (number crunching). For example, weather forecasting, scientific simulations, (animated) graphics, fluid dynamic calculations, nuclear energy research, electronic design, and analysis of geological data (e.g. in petrochemical prospecting). MOTHERBOARD

BUSES

The CPU of personal computer has to send and receive various types of information and data to and from all other devices and components inside a computer and to devices connected to outer world of computer. If we remove the case of CPU then we will see that there is a mesh of wires or electronics pathways connected between motherboard and other components. These are the wires or electronics pathways that join various components together to communicate with each other. This network of wires or electronics pathways is known as 'BUS'. Thus BUS is simply a set of wires of lines that connects various components inside a computer.

Types of Buses: Mainly, Computer's BUS can be divided into two types: Internal Bus External Bus Internal Bus: A BUS or set of wires which connects the various components inside a computer is known as Internal Bus. As it is used for internal communication purposes. It connects various components inside the cabnet, like as CPU, Memory and Motherboard. It is also known as System Bus. External Bus: A Bus or set of wires which is used to connect outer peripherals or components to computer, is known as External Bus. It allows different external devices to be connected to computer. It is slower than Internal or System Bus. It is also known as Expansion Bus.

System Bus A system bus is a single computer bus that connects the major components of a computer system. The technique was developed to reduce costs and improve modularity. It combines the functions of a data bus to carry information, an address bus to determine where it should be sent, and a control bus to determine its operation. Although popular in the 1970s and 1980s, modern computers use a variety of separate buses adapted to more specific needs.

Background Many early electronic computers were based on the First Draft of a Report on the EDVAC report published in 1945. In what became known as the Von Neumann architecture, a central control unit and arithmetic logic unit (ALU, which he called the central arithmetic part) were combined with computer memory and input and output functions to form a stored program computer. The Report presented a general organization and theoretical model of the computer, however, not the implementation of that model. Soon designs integrated the control unit and ALU into what became known as the central processing unit (CPU). Computers in the 1950s and 1960s were generally constructed in an ad-hoc fashion. For example, the CPU, memory, and input/output units were each one or more cabinets connected by cables. Engineers used the common techniques of standardized bundles of wires and extended the concept as backplanes were used to hold printed circuit boards in these early machines. The name "bus" was already used for "bus bars" that carried electrical power to the various parts of electric machines, including early mechanical calculators. The advent of integrated circuits vastly reduced the size of each computer unit, and buses became more standardized. Standard modules could be interconnected in more uniform ways and were easier to develop and maintain. Description To provide even more modularity with reduced cost, memory and I/O buses (and the required control and power buses) were sometimes combined into a single unified system bus. Modularity and cost became important as computers became small enough to fit in a single cabinet (and customers expected similar price reductions). Digital Equipment Corporation (DEC)

further reduced cost for mass-produced minicomputers, and memory-mapped I/O into the memory bus, so that the devices appeared to be memory locations. This was implemented in the Unibus of the PDP-11around 1969, eliminating the need for a separate I/O bus. Even computers such as the PDP-8 without memory-mapped I/O were soon implemented with a system bus, which allowed modules to be plugged into any slot. Some authors called this a new streamlined "model" of computer architecture. Many early microcomputers (with a CPU generally on a single integrated circuit) were built with a single system bus, starting with the S-100 bus in the Altair 8800 computer system in about 1975. The IBM PC used the Industry Standard Architecture (ISA) bus as its system bus in 1981. The passive backplanes of early models were replaced with the standard of putting the CPU on a motherboard, with only optional daughter boards or expansion cards in system bus slots. The Multibus became a standard of the Institute of Electrical and Electronics Engineers as IEEE standard 796 in 1983. Sun Microsystems developed the SBus in 1989 to support smaller expansion cards. The easiest way to implement symmetric multiprocessing was to plug in more than one CPU into the shared system bus, which was used through the 1980s. However, the shared bus quickly became the bottleneck and more sophisticated connection techniques were explored

Dual independent bus As CPU design evolved into using faster local buses and slower peripheral buses, Intel adopted the dual independent bus (DIB) terminology, using the external front-side bus to the main system memory, and the internal back-side bus between one or more CPUs and the CPU caches. This was introduced in the Pentium Pro and Pentium II products in the mid to late 1990s.

The primary bus for communicating data between the CPU and main memory and input and output devices is called the front-side bus, and the back-side bus accesses the level 2 cache. Modern personal and server computers use higher-performance interconnection technologies such as Hyper Transport and Intel Quick Path Interconnect, while the system bus architecture continued to be used on simpler embedded microprocessors. The systems bus can even be internal to a single integrated circuit, producing a system-on-a-chip. Examples include AMBA, Core Connect, and Wishbone.

Power supply A power supply is a device that supplies electric power to an electrical load. The term is most commonly applied to electric power converters that convert one form of electrical energy to another, though it may also refer to devices that convert another form of energy (mechanical, chemical, solar) to electrical energy. A regulated power supply is one that controls the output voltage or current to a specific value; the controlled value is held nearly constant despite variations in either load current or the voltage supplied by the power supply's energy source. Every power supply must obtain the energy it supplies to its load, as well as any energy it consumes while performing that task, from an energy source. Depending on its design, a power supply may obtain energy from: 

Electrical energy transmission systems. Common examples of this include power supplies that convert AC line voltage to DC voltage.



Energy storage devices such as batteries and fuel cells.



Electromechanical systems such as generators and alternators.



Solar power.

A power supply may be implemented as a discrete, stand-alone device or as an integral device that is hardwired to its load. Examples of the latter case include the low voltage DC power supplies that are part of desktop computers and consumer electronics devices. Commonly specified power supply attributes include: 

The amount of voltage and current it can supply to its load.



How stable its output voltage or current is under varying line and load conditions.



How long it can supply energy without refueling or recharging (applies to power supplies that employ portable energy sources).

PROCESSOR ARCHITECTURES VON-NEUMANN MACHINES: 1. The invention of stored program computers has been described by a mathematician, John von Neumann, who was a contemporary of Mauchley and Eckert. 2. Stored-program computers have become known as von Neumann Architecture systems. Today’s stored-program computers have the following characteristics: – Three hardware systems: • A central processing unit (CPU) • A main memory system • An I/O system -The capacity to carry out sequential instruction processing. -A single data path between the CPU and main memory. This single path is known as the von Neumann bottleneck.

o A main memory, which stores both data and instructions. o An arithmetic-logical unit (ALU) capable of operating on binary data. o A control unit, which interprets the instructions in memory and causes them to be executed. o Input and output (I/O) equipment operated by the control unit.

NON-VON-NEUMANN MACHINES • Conventional stored-program computers have undergone many incremental improvements over the years. • These improvements include adding specialized buses, floating-point units, and cache memories etc. • But enormous improvements in computational power require departure from the classic von Neumann architecture. • Adding processors is one approach. The term non-von Neumann computers refer to the class of machines that are not based upon the architecture of a sequential machine. A non von Neumann machine may thus be without the concept of sequential flow of control (i.e. without any register corresponding to a “program counter” that indicates the current point that has been reached in execution of a program) and/or without the concept of a variable (i.e. without “named” storage locations in which a value may be stored and subsequently referenced or changed). RISC (Reduced Instruction Set Computer): • Microprocessor architecture. • Designed to perform a set of smaller computer instructions so that it can operate at higher speeds. • It is also called hard-wired approach • Small, highly optimized set of instructions • Uses a load-store architecture • Short execution time • Pipelining • Many registers

Examples of RISC processors: • IBM RS6000, MC88100. • DEC’s Alpha 21064, 21164 and 21264 processors Features of RISC Processors: The standard features of RISC processors are listed below: • RISC processors use a small and limited number of instructions. • RISC machines mostly uses hardwired control unit. • RISC processors consume less power and are having high performance. • Each instruction is very simple and consistent. • RISC processors use simple addressing modes. • RISC instruction is of uniform fixed length. CISC (Complex Instruction Set Computer): A complex instruction set computer (CISC) is a microprocessor instruction set architecture (ISA) in which each instruction can execute several low-level operations, such as a load from memory, an arithmetic operation, and a memory store, all in a single instruction.

Examples of CISC processors are:  Intel 386, 486, Pentium, Pentium Pro, Pentium II, Pentium III  Motorola’s 68000, 68020, 68040, etc.

Features of CISC Processors: The standard features of CISC processors are listed below:  CISC chips have a large amount of different and complex instructions.  CISC machines generally make use of complex addressing modes.  Different machine programs can be executed on CISC machine.  CISC machines uses micro-program control unit.  CISC processors are having limited number of registers. Difference between CISC and RISC

CISC  Primary goal is to complete a task in as few lines of assembly as possible  Emphasis on hardware  Includes multi-clock complex instructions  Memory-to-memory: "LOAD" and "STORE" incorporated in instructions  Difficult to apply pipelining.  Small code sizes, high cycles per second

RISC  Primary goal is to speedup individual instruction  Emphasis on software  Single-clock, reduced instruction only  Register to register: "LOAD" and "STORE" are independent instructions  Easy to apply pipelining.  Low cycles per second, large code sizes

SUPERSCALAR PROCESSORS Several instructions are executed in the same clock cycle by the processor. Such processors are capable of achieving an instruction execution throughput of more than one instruction per cycle. They are known as superscalar processors. Superscalar processing is used for fast microprocessors. By exploiting instruction-level parallelism, superscalar processors are capable of executing more than one instruction in a clock cycle. Superscalar processing, the ability to initiate multiple instructions during the same clock cycle, is known as latest architectural innovations aimed at producing fast microprocessors. Superscalar microprocessors are now being designed and produced by all the microprocessor vendors for high-end-products. The superscalar methods have been applied to a spectrum of instruction sets, ranging from the Digital Equipment. ADDRESSING MODES The address field or fields in a typical instruction format are relatively small. We should be able to reference a large range of locations in main memory. For this, a variety of addressing techniques has been employed. The most common addressing techniques are: • ...