Hardware e Software das Tecnologias de Informação
Transcription
Hardware e Software das Tecnologias de Informação
Hardware e Software das Tecnologias de Informação V 0.2, V.Lobo, EN/ISEGI, 2013 Hardware e Software das TI O mundo é apenas uma sequência de 0s e 1s Prof. Doutor Victor Lobo Licenciatura em Sistemas e Tecnologias de Informação Objectivo desta disciplina Programa (traços gerais) 1. Introdução às máquinas de computação Representação de dados 3. Álgebra de Boole 4. Sistemas Digitais 5. Arquitectura de Computadores 6. Microprocessadores 7. Sistemas de Memória 8. Periféricos 9. Sistemas Operativos e Linguagens de programação Compreender o HARDWARE 2. De que dispositivos são feitos os computadores ? que é a arquitectura de um computador ? O que é um microprocessador ? O Compreender os tipos de SOFTWARE Linguagem máquina de alto nível Sistemas operativos e “device drivers” Linguagens Porque é que é importante ? Para compreender o mundo que nos rodeia ! Porque só compreendendo como são as máquinas podemos compreender: As suas limitações As suas potencialidade Como escolhê-las e comprá-las, e fazer bom uso delas Porque faz parte do curriculum de STI… Para Bibliografia Livro de texto Computer Organization and Architecture, Linda Null & Julia Lobur, Jones and Bartlett, 2006 Outros Introdução às Ciências da Computação An Invitation to Computer Science, 5th Ed, G.Michael Schneider, Judith Gersting Breve introdução com hardware recente Introdução geral a S.I. acabar o curso é preciso saber isto (!) Tecnologias de Informação, Sérgio Sousa, FCA, 2009. Introduction to Information Systems, Rainer, Turban et al., John Wiley & Sons, 2011 1 Hardware e Software das Tecnologias de Informação V 0.2, V.Lobo, EN/ISEGI, 2013 Bibliografia (mais detalhada) Avaliação Sistemas Digitais e Microprocessaores Digital Fundamentals (10th Ed), Floyd, Prentice-Hall, 2010 Sistemas Digitais, Padilha, McGraw-Hill Exame Final Obrigatório Trabalhos Mini-Testes Sistemas Operativos Modern Operating Systems (3rd Ed), Tannenbaum, Prentice-Hall, 2007 Sistemas Operativos, Alves Marques et al., FCA, 2009. Datas: 23-Set 30-Set 7-Out 14-Out 4-Nov 11-Nov 18-Nov 25-Nov 2-Dez 9-Dez (recup) de pesquisa bibliográfica e apresentação (10%) Lista de temas disponível no site da cadeira Fazer uma apresentação de 10 min e relatório de 2 páginas. NOTA Apresentações dos trabalhos de Programação em Assembler (20%) Data de Entrega: 2 Janeiro Trabalho (10+10%) Datas: 3 de Outubro & 11 de Novembro Trabalho para todos (50 % da nota) MÍNIMA EM TODAS AS PROVAS – 9 valores Horário de dúvidas e contactos Email: vlobo@isegi.unl.pt Dúvidas 2ª Feira às 18:30 (ou quando combinarmos) Por mail em qualquer altura Sempre que estiver no ISEGI (!) Material de apoio www.isegi.unl.pt/docentes/vlobo Mudanças de aulas Não há aula de HSTI no dia 21 e 24 de Outubro 1.3 An Example System Um exemplo: Computadores e a sua história O que é isto tudo?? 2 Hardware e Software das Tecnologias de Informação V 0.2, V.Lobo, EN/ISEGI, 2013 Elementos básicos de um computador Arquitectura básica de Von Neumann Computadores Digitais Saída de dados Unidade de Processamento Manipular os dados, fazer as contas, processar a informação Guardar Operações Unidade de Armazenamento os dados Memória Controlo de aritmética e lógica (p/dados e programa) Unidade de Entrada/Saída (I/O) Comunicar com o exterior Entrada de dados Componentes do sistema Componentes do sistema Visão externa (rede, scanner, etc) Bus de sistema / bus de expansão Visão interna Memória principal CPU processamento dos dados e controlo do sistema Teclado Monitor (video) Ligação através de uma “placa controladora” e programa (“driver”) dedicado Impressora Disco/ Disquettes Outros História das máquinas de computação Máquinas que servem para processar informação História das máquinas de computação Fazer contas, guardar dados, automatizar processos Máquina de Turing, artigo “sobre os números computáveis” Primeiras máquinas “modernas” Antes dos computadores Ábacos Máquina de Pascal e de Leibniz Tabelas de logaritmos, e “computador moderno mecânico” Máquinas de Hollerith Leitura de cartões, e processamento rudimentar de informação Máquinas analógicas dedicadas 2ª Grande guerra ENIAC Máquinas de Babbage Somas e subtracções com rodas dentadas Calculadores de tiro para artilharia Trabalho teórico dos anos 30 / Colossus / outros Computadores de 1ª Geração Válvulas UNIVAC (Sperry), ERA, Aprox. 1945 - 1953 IBM 650 3 Hardware e Software das Tecnologias de Informação V 0.2, V.Lobo, EN/ISEGI, 2013 História das máquinas de computação Computadores de 2ª Geração Transistors discretos IBM 7095,1401, primeiros História das máquinas de computação Computadores de 4ª Geração VLSI, PDP 1954-1965 Cray 1.5 Historical Development workstations / minicomputadores / mainframes / supercomputadores Computadores de 3ª Geração Circuitos integrados IBM 360, PDP-8, DEC-10, 1965-1980 Moore’s Law (1965) Gordon 1.5 Historical Development Moore, Intel founder density of transistors in an integrated circuit will double every year.” cost of capital equipment to build semiconductors will double every four years.” In “The density of silicon chips doubles every 18 months.” Rock’s Law In 2005, a chip plants under construction cost over $2.5 billion. $2.5 billion is more than the gross domestic product of some small countries, including Belize, Bhutan, and the Republic of Sierra Leone. For Moore’s Law to hold, Rock’s Law must fall, or vice versa. But no one can say which will give out first. 1968, a new chip plant cost about $12,000. At the time, $12,000 would buy a nice home in the suburbs. An executive earning $12,000 per year was “making a very comfortable living.” But this “law” cannot hold forever ... Rock, Intel financier “The Contemporary version: 1.5 Historical Development Rock’s Law Arthur “The microprocessadores 1980 - …(1ºp em 1974) Computadores pessoais / 1.6 The Computer Level Hierarchy Computers consist of many things besides chips. Before a computer can do anything worthwhile, it must also use software. Writing complex programs requires a “divide and conquer” approach, where each program module solves a smaller problem. Complex computer systems employ a similar technique through a series of virtual machine layers. 4 Hardware e Software das Tecnologias de Informação V 0.2, V.Lobo, EN/ISEGI, 2013 1.6 The Computer Level Hierarchy Each virtual machine layer is an abstraction of the level below it. The machines at each level execute their own particular instructions, calling upon machines at lower levels to perform tasks as required. Level 4: Assembly Language Level The 1.6 The Computer Level Hierarchy Level 2: Machine Level Also known as the Instruction Set Architecture (ISA) Level. Consists of instructions that are particular to the architecture of the machine. Level 3: System Software Level Controls executing processes on the system. Protects system resources. Assembly language instructions often pass through Level 3 without modification. Level 1: Control Level A control unit decodes and executes instructions and moves data through the system. Control units can be microprogrammed or hardwired. A microprogram is a program written in a lowlevel language that is implemented by the hardware. Hardwired control units consist of hardware that directly executes machine instructions. Level 5: High-Level Language Level level with which we interact when we write programs in languages such as C, Pascal, Lisp, and Java. upon assembly language produced from Level 5, as well as instructions programmed directly at this level. 1.6 The Computer Level Hierarchy execution and user interface level. level with which we are most familiar. The Acts Level 6: The User Level Program Computer circuits ultimately carry out the work. 1.6 The Computer Level Hierarchy 1.6 The Computer Level Hierarchy Programs written in machine language need no compilers, interpreters, or assemblers. 1.6 The Computer Level Hierarchy Level 0: Digital Logic Level This level is where we find digital circuits (the chips). Digital circuits consist of gates and wires. These components implement the mathematical logic of all other levels. 5 Hardware e Software das Tecnologias de Informação V 0.2, V.Lobo, EN/ISEGI, 2013 1.7 The von Neumann Model On the ENIAC, all programming was done at the digital logic level. Programming the computer involved moving plugs and wires. A different hardware configuration was needed to solve every unique problem type. Configuring the ENIAC to solve a “simple” problem required many days labor by skilled technicians. 1.7 The von Neumann Model 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 1.7 The von Neumann Model Inventors of the ENIAC, John Mauchley and J. Presper Eckert, conceived of a computer that could store instructions in memory. The invention of this idea has since been ascribed to a mathematician, John von Neumann, who was a contemporary of Mauchley and Eckert. Stored-program computers have become known as von Neumann Architecture systems. 1.7 The von Neumann Model This is a general depiction of a von Neumann system: These computers employ a fetchdecode-execute cycle to run programs as follows . . . 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. 1.7 The von Neumann Model The control unit fetches the next instruction from memory using the program counter to determine where the instruction is located. 1.7 The von Neumann Model The instruction is decoded into a language that the ALU can understand. 6 Hardware e Software das Tecnologias de Informação V 0.2, V.Lobo, EN/ISEGI, 2013 1.7 The von Neumann Model Any data operands required to execute the instruction are fetched from memory and placed into registers within the CPU. 1.8 Non-von Neumann Models 1.7 The von Neumann Model The ALU executes the instruction and places results in registers or memory. 1.8 Non-von Neumann Models Conventional stored-program computers have undergone many incremental improvements over the years. In the late 1960s, high-performance computer systems were equipped with dual processors to increase computational throughput. These improvements include adding specialized buses, floating-point units, and cache memories, to name only a few. In the 1970s supercomputer systems were introduced with 32 processors. But enormous improvements in computational power require departure from the classic von Neumann architecture. Supercomputers with 1,000 processors were built in the 1980s. In 1999, IBM announced its Blue Gene system containing over 1 million processors. Adding processors is one approach. 1.8 Non-von Neumann Models Conclusion Parallel processing is only one method of providing increased computational power. More radical systems have reinvented the fundamental concepts of computation. This chapter has given you an overview of the subject of computer architecture. These advanced systems include genetic computers, quantum computers, and dataflow systems. You should now be sufficiently familiar with general system structure to guide your studies throughout the remainder of this course. At this point, it is unclear whether any of these systems will provide the basis for the next generation of computers. Subsequent chapters will explore many of these topics in great detail. 7