©Brooks/Cole, 2003 Chapter 1 Introduction

©Brooks/Cole, 2003 Figure 1-1 Data processor model This model represents a specific-purpose computer not a general-purpose computer.

©Brooks/Cole, 2003 Figure 1-2 Programmable data processor model - A program is a set of instructions that tells the computer what to do with data. - Instructions are written in a computer language. - Output data depends on the input data and the program.

©Brooks/Cole, 2003 Figure 1-3 Same program, different data

©Brooks/Cole, 2003 Figure 1-4 Same data, different programs

©Brooks/Cole, 2003 Figure 1-5 von Neumann model -Memory is the storage area where data and program is stored -ALU is where calculation and logical operation take place. -CU controls the operations of memory, ALU and I/O devices -Input subsystem accepts input and the program from outside. -Output subsystem sends the result of processing to outside,

©Brooks/Cole, 2003 Figure 1-6 Program and data in memory -Both the data and programs should have the same format because they are stored in memory as binary pattern ( sequence of 0s & 1’s). -Control unit executes instructions sequentially as follows: fetches one instruction from memory, interprets it, and then executes it.

©Brooks/Cole, 2003 Figure 1-7 Program made of instructions -Before a programmer find the appropriate instructions of the program, he/she should first solve the problem in a step-by-step manner (Algorithm). -Programs are written using a computer language that has limited number of symbols and words. -