BCCch1

Slide 1: 

Chapter 1 Introduction

Slide 2: 

After reading this chapter, the reader should be able to: OBJECTIVES

Slide 3: 

THE COMPUTER AS A BLACK BOX 1.1

Slide 4: 

Figure 1-1 Data processor model Data processor model

Slide 5: 

Figure 1-2 Programmable data processor model Programmable Data processor model Computers – general-purpose machines

Program : 

Program A program is a set of instructions that tells the computer what to do with data. written in a computer language.

Slide 7: 

Figure 1-3 Same program, different data Same program, different data

Slide 8: 

Figure 1-4 Same data, different programs Same data, different programs

Slide 9: 

von NEUMANN MODEL 1.2

von Neumann Model : 

von Neumann Model Every computer today is based on the von Neumann Model. It is based on 3 ideas: Four subsystems Stored Program Concept Sequential Execution of Instructions

Slide 11: 

Figure 1-5 von Neumann model Four subsystems: Memory – the storage area of programs and data. ALU – arithmetic/logic operations take place Control Unit – control Memory, ALU, and I/O I/O – accept input data/send output data

Input/Output Subsystem : 

Input/Output Subsystem The definition is very broad;it includes the secondary storage devices. Disk – stores data and programs for processing

Stored Program Concept : 

Stored Program Concept The von Neumann model states thatthe program must be stored in memory. The memory of modern computershosts both a program its corresponding data

Sequential Execution of Instructions : 

Sequential Execution of Instructions A program is made of a finite number of instructions. The control unit fetches one instruction from memory interpret it execute it The instructions are executed one after another.

Slide 15: 

COMPUTER HARDWARE 1.3

Slide 16: 

ALU Control unit Registers

Slide 17: 

DATA 1.4

Storing Data : 

Storing Data Store data in the form of an electrical signal, specially its presence or absence. This implies that a computer can store data in one of two states. Binary number system

Data organization : 

Data organization Although data should be stored only in one form (a binary pattern) inside a computer,data outside a computer can take many forms. Data come in different forms: Numbers Text Images Audio Video

Slide 20: 

COMPUTER SOFTWARE 1.5

Requirements of von Neumann model : 

Requirements of von Neumann model The programs must be stored in memory. (Fig. 1.6) The programs must be a sequence of instructions. (Fig. 1.7)

Slide 22: 

Figure 1-6 Program and data in memory Fig. 1.6

Slide 23: 

Figure 1-7 Program made of instructions Fig. 1.7 Program made of instructions

Algorithm : 

Algorithm A programmer should first solve the problem in a step-by-step manner and then try to find the appropriate sequence of instructions that solves the problem. The step-by-step solutionis called an algorithm

Operating Systems : 

Operating Systems An operating system originally worked as a manager to facilitate access of the computer components for a program.

Slide 26: 

HISTORY 1.6

Before 1950 : 

Before 1950 Mechanical machines (before 1930) Early electronic computers (1930-1950) ENIAC (Electronic Numerical Integrator and Calculator)first general-purpose, totally electronic computerUniversity of Pennsylvania, 1946

1950 : 

1950 The preceding computers used memory only for storing data. EDVACthe first computer based on von Neumann’s idea,University of Pennsylvania,1950

Computer generations(1950-present) : 

Computer generations(1950-present) 1st generation (1950-1959)vacuum tubes 2nd generation (1959-1965)transistors, High-level languages(FORTRAN, COBOL) 3rd generation (1965-1975)IC(Integrated Circuit), Minicomputer, software industry was born 4th generation (1975-1985)VLSI, microcomputer 5th generation (1985-)laptop and palmtop computer

Microcomputer : 

Microcomputer Microcomputers are designed to be used by individuals, whether in the form of PCs, workstations or notebook computers. A microcomputer contains a CPU on a microchip (the microprocessor), a memory system (typically ROM and RAM), a bus system and I/O ports, typically housed in a motherboard.