Câu hỏi về máy tính

Question 1. What is a computer?A computer may be defined as a machine which accepts data from an input device, processes it by performing arithmetical and logic operations in accordance with a program of instructions and returns the results through an output unit.
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Câu hỏi về máy tính 1 Computer system Computer SystemBook I: computer system fundamentals.Chapter 1: INTRODUCTION TO COMPUTER.Question 1. What is a computer?A computer may be defined as a machine which accepts data froman input device, processes it by performing arithmetical andlogic operations in accordance with a program of instructionsand returns the results through an output unit.A computer is basically an electronic machine operating oncurrent.Question 2. Components of a Computer system?A computer system comprises of the following components: 2 1. Central Processing Unit (CPU). - CPU is the heart of the whole sys - CPU consists of the : • control unit (CU) • arithmetic logic unit (ALU) • accumulator (ACC) • program counter (PC) • instruction register (IR) • memory address register (MAR) • memory data register (MDR) • status register (SR) • general purpose register - The function of each components of CPU: • Control unit: control and co_ordinate all hardware functions of the CS. examine and decode all program instructions to the computer and initiate their execution by sending the appropriate signals. • ALU: performs all arithmetic and logic comparision two values functions required by computer. • ACC: holds the first operand of the temporary result of the ALU. • PC: contains the add of the next instruction to be excuted. • IR: contains the current instruction to be executed.Main memory • MAR: holds the address location to or from which data is to be transferred • MDR: contains the data to be written to or read out of the addressed location. • SR: keeps track of the status of the accumalator. • General Purpose Register: for general purpose procedures. 3Please refer to diagram for an illustratin of the basiccomponents of the CPU. CPU I N Control unit T E Arithmetic Logic Unit R Accumulator N A Program Couter L to main Instruction Register B memory U S Memory Address Register Memory Data Register Status Register General Purpose Register Basic components of a CPU. Control Unit Input Unit ALUOutput Unit Main Memory Backing Storage Control signals Data flow Components of a CS. 2. Input units - Used to enter data( raw unprocessed facts) and instructions to the computer. 3. Output units - Used for delevering the processed result from the computer in useful form. 4. Backing storage units 4 - Backing storage units need for high capacity data storage devices that can store data in a more permanent form for later retrieral, updating and referencing. - Backing storage is also called secondary storage external storage and auxiliary storage.Chapter 2: MICOPROCESSOR.Question 1. Cache Memory? - Cache memory is a small amount of very fast store with faster access time than the main memory. - Cache memory is used to temporaryty store data instructions that are likely to be retrieved many times, thus speeds up the processing of data. - Sits between main storage and the processor acting as holding area through which all data and instructions pass. - Old data in the cache memory is over written by new then cache is full.Question 2. Virtual Memory? - Virtual memory makes use of both the main memory and backing store. - In a virtual memory sys, each user has the illusion that his program is in the main memory all the time. - The sys maintains this illusion by keeping some of the “unused” portion of the program’s code and data on a backing store device which is usually magnetic disk - The movement of the unused portion from the backing store to the mian memory is transparent to the users. - Please refer to diagram for virtual memory. Backing Store Main Memory A3 A2 A1 ...