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1、计算机导论考前辅导学习方法应试方法 认真对待作业题,作业题就是考试题 老师上课讲的内容就是考试内容(不必死扣书本) 考试不交白卷,越不会越多写(相关公式、概念、自己的想法) 大学考试考的是记忆力,请珍惜自己的大脑 神通广大的打印店(复习资料、历年试卷)Chapter 1 IntroductionComputer Is a programmable data processor that accepts input data and programs and outputs data.Computer System Solve problems and interact with their e
2、nvironment. They consist of Devices, programs, and data.Program Is a set of instructions executed sequentially that tells the computer what to do with data.Chapter 1 IntroductionVon Neumann ModellFour Subsystems MemoryMemory(内存) Arithmetic Arithmetic Logic Logic UnitUnit(ALU ALU ,算术逻辑单元) Control Uni
3、t Control Unit(控制器) Input/Output Input/Output(输入/输出设备)lStored Program ConceptlSequential Execution Of InstructionsChapter 2 Data RepresentationData TypeslText BytelNumber ASCIIlImage Bitmap,Vector,Pixel,ResolutionlAudio Digital,AnaloglVideo FrameChapter 2 Data RepresentationTextlBit (位) A bit (binar
4、y digit) is the smallest unit of data that can be stored in a computer,it is either 0 or 1. lBit Pattern(位组合格式) A bit pattern is a sequence, or as it is sometimes called, a string of bits that can represent a symbol. lByte(字节) A bit pattern of length 8 is called a byte. Chapter 2 Data Representation
5、NumberlASCII American Standard Code for Information Interchange (ASCII)(美国信息交换标准代码). This code uses 7 bits for each symbol. This means 128 different symbols can be defined by this code.Chapter 2 Data RepresentationImagelBitmap Graphic Pixel: Picture elementsResolution: The size of the pixelChapter 2
6、 Data RepresentationImagelVector Graphic An image is decomposed into a combination of curves and lines. Each curve or line is represented by a mathematical formula.Chapter 3 Number RepresentationConcepts Decimal system (十进制十进制) based on 10,0-9; Binary system (二进制二进制) based on 2,0-1; Octal notation (
7、八进制八进制) based on 8,0-7; Hexadecimal notation (十六进制十六进制) based on 16 ,0-9,A-F。Chapter 3 Number RepresentationConversionConversion Decimal Binary Hexadecimal notation Octal notationChapter 3 Number RepresentationInteger Representation Unsigned Integer(无符号整数)(无符号整数) Overflow(溢出)(溢出) Sign-and-Magnitude
8、Format(原码)原码) +0 00000000 -0 10000000Range: 0 . (2N-1)Range: -(2N-1-1) +(2N-1-1)Chapter 3 Number RepresentationInteger Representation Ones Complement Format(反码反码) +0 00000000 -0 11111111 Twos Complement Format(补码)补码)Range: -2N-1 +(2N-1-1)Range: -(2N-1-1) +(2N-1-1)Chapter 3 Number RepresentationExces
9、s System Magic Number Is normally (2N-1) or (2N-1-1), where N is the bit allocation. Example: Represent 25 in Excess_127 using an 8-bit allocation. -25 + 127 102 1100110 01100110Chapter 3 Number RepresentationFloating-Point Representation 1. Convert the integer part to binary. 2. Convert the fractio
10、n to binary. 3. Put a decimal point between the two parts.Example: Transform the fraction 0.875 to binary0.875 1.750 1.5 1.0 0.0 0 . 1 1 1Chapter 3 Number RepresentationNormalization Example: Show the representation of the normalized number + 26 x 1.01000111001 6 + 127 133 10000101 Sign exponent man
11、tissa -+1010001.1101-111.000011+0.00000111001-001110011- 6 26 3 Normalized - +26 x 1.01000111001 -22 x 1.11000011 +2-6 x 1.11001 -2-3 x 1.110011Chapter 4 Operations on BitsArithmetic Operations Example1: Solution: Add two numbers in twos complement representation: (+24) + (-17) (+7)Carry 1 1 1 1 10
12、0 0 1 1 0 0 0 1 1 1 0 1 1 1 1-Result 0 0 0 0 0 1 1 1 +7Chapter 4 Operations on BitsArithmetic Operations Example2: Solution:Add two numbers in twos complement representation: (+127) + (+3) (+130)Carry 1 1 1 1 1 1 1 0 1 1 1 1 1 1 1 0 0 0 0 0 0 1 1 -Result 1 0 0 0 0 0 1 0 -126(Error)An overflow has oc
13、curred. Chapter 4 Operations on BitsArithmetic Operations Example3: Solution: Subtract 62 from 101 in twos complement: (+101) - (+62) (+101) + (-62)Carry 1 10 1 1 0 0 1 0 1 1 1 0 0 0 0 1 0-Result 0 0 1 0 0 1 1 1 39The leftmost carry is discarded.Chapter 4 Operations on BitsLogical OperationsChapter
14、4 Operations on BitsLogical OperationsExample1:Solution:Use the NOT operator on the bit pattern 10011000.Chapter 4 Operations on BitsLogical OperationsExample2:Solution:Use the AND operator on bit patterns 10011000 and 00110101.Chapter 4 Operations on BitsLogical OperationsExample3:Solution:Use the
15、OR operator on bit patterns 10011000 and 00110101.Chapter 4 Operations on BitsLogical OperationsExample4:Solution:Use the XOR operator on bit patterns 10011000 and 00110101.Chapter 4 Operations on BitsLogical OperationsExample5:Solution:Use a mask to unset (clear) the 5 leftmost bits of a pattern. T
16、est the mask with the pattern 10100110.ANDChapter 4 Operations on BitsShift Operations Shift operations can only be used when a pattern represents an unsigned number. 左移:左移: *2 右移:右移: / 2Chapter 5 Computer OrganizationMain Memory-Kilobyte(K)Megabyte(M)Gigabyte(G)Terabyte(T)Petabyte(P)Exabyte(E)-210 bytes220 bytes230 bytes240 bytes250 bytes260 bytes-103 bytes106 bytes109 bytes1012 bytes1015 bytes1018 bytesKB Kilobyte:千字节,1024字节MB Megabyte:兆字节GB Gigabyte:十亿字节TB Terabyte:1000吉千兆字节GB;兆兆位Chapter 5 Co