Computer guys pls help me..........

humpty dumpty

Well-known member
  • Oct 3, 2010
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    I want to learn about some basics in computer & network technology.
    Can anyone teach me,


    1) Sign & magtitude representation
    2) 1's complement reresentation
    3) 2's complement reresentation
    4) Fixed point representaion
    5) Floating point representaion
    6) Standerd floating point representaion
    7) Representaion of characters (ASCII code, ASCII-8 code, EBCDIC code)



    Thank u................... :D
     

    Nisala88

    Well-known member
  • Oct 24, 2006
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    ~Madhouse~
    Sign & magtitude representation

    An n-bit word can have 2 to the power n possible different values from 0 to 2 to the power n -1, for example, an 8-bit word can represent the numbers 0,1,....,254,255. One way of representing a negative number is to take the most significant bit and reserve it to indicate the sign of the number. The usual conversation is to choose the sign bit to be 0 to represent positive numbers and to choose it to be 1 to represent negative numbers.

    for example, in 8 bits we can interpret the two numbers 00001101 and 10001101

    0 - sign bit
    0001101 (number magnitude) = + 13 subscript 10

    and

    1 - sign bit
    0001101 (number magnitude) = - 13 subscript 10

    Using a sign magnitude representation is a perfect valid way to represent signed numbers, although it is not widely used in integer arithmetic. The range of a sign and magnitude number in n bits is given by,

    -(2 to the power (n-1) - 1) to +(2 to the power (n-1) - 1)

    All we have done is to take an n bit number, use one bit to represent the sign and left the remaining n-1 bits to represent the number.
    One of the objections to this system is that it has two values for zero,

    00000000 = +0 and 10000000 = -0

    mage 1st year text book eken balan gahuwe, bohoma keti karala, mamahithanawa meka prayojanawath wei kiyala
     

    humpty dumpty

    Well-known member
  • Oct 3, 2010
    2,042
    451
    83
    On the wall
    Sign & magtitude representation

    An n-bit word can have 2 to the power n possible different values from 0 to 2 to the power n -1, for example, an 8-bit word can represent the numbers 0,1,....,254,255. One way of representing a negative number is to take the most significant bit and reserve it to indicate the sign of the number. The usual conversation is to choose the sign bit to be 0 to represent positive numbers and to choose it to be 1 to represent negative numbers.

    for example, in 8 bits we can interpret the two numbers 00001101 and 10001101

    0 - sign bit
    0001101 (number magnitude) = + 13 subscript 10

    and

    1 - sign bit
    0001101 (number magnitude) = - 13 subscript 10

    Using a sign magnitude representation is a perfect valid way to represent signed numbers, although it is not widely used in integer arithmetic. The range of a sign and magnitude number in n bits is given by,

    -(2 to the power (n-1) - 1) to +(2 to the power (n-1) - 1)

    All we have done is to take an n bit number, use one bit to represent the sign and left the remaining n-1 bits to represent the number.
    One of the objections to this system is that it has two values for zero,

    00000000 = +0 and 10000000 = -0

    mage 1st year text book eken balan gahuwe, bohoma keti karala, mamahithanawa meka prayojanawath wei kiyala


    Thank u bro............. :D
     

    Nisala88

    Well-known member
  • Oct 24, 2006
    4,206
    735
    113
    ~Madhouse~
    1's complement representation

    Alternatively, a system known as ones' complement can be used to represent negative numbers. The ones' complement form of a negative binary number is the bitwise NOT applied to it — the "complement" of its positive counterpart. Like sign-and-magnitude representation, ones' complement has two representations of 0: 00000000 (+0) and 11111111 (−0).

    As an example, the ones' complement form of 00101011 (43) becomes 11010100 (−43). The range of signed numbers using ones' complement is represented by −(2 to the power (n−1)−1) to +(2 to the power (n−1)−1) and ±0. A conventional eight-bit byte is −127 subscript 10 to +127 subscript 10 with zero being either 00000000 (+0) or 11111111 (−0).

    To add two numbers represented in this system, one does a conventional binary addition, but it is then necessary to add any resulting carry back into the resulting sum. To see why this is necessary, consider the following example showing the case of the addition of −1 (11111110) to +2 (00000010).

    9gas0z.jpg


    In the previous example, the binary addition alone gives 00000000, which is incorrect. Only when the carry is added back in does the correct result (00000001) appear.

    mekanam gaththe WIKI walin, text book eke thiyena theory eka meeta wada amarui.
     

    humpty dumpty

    Well-known member
  • Oct 3, 2010
    2,042
    451
    83
    On the wall
    1's complement representation

    Alternatively, a system known as ones' complement can be used to represent negative numbers. The ones' complement form of a negative binary number is the bitwise NOT applied to it — the "complement" of its positive counterpart. Like sign-and-magnitude representation, ones' complement has two representations of 0: 00000000 (+0) and 11111111 (−0).

    As an example, the ones' complement form of 00101011 (43) becomes 11010100 (−43). The range of signed numbers using ones' complement is represented by −(2 to the power (n−1)−1) to +(2 to the power (n−1)−1) and ±0. A conventional eight-bit byte is −127 subscript 10 to +127 subscript 10 with zero being either 00000000 (+0) or 11111111 (−0).

    To add two numbers represented in this system, one does a conventional binary addition, but it is then necessary to add any resulting carry back into the resulting sum. To see why this is necessary, consider the following example showing the case of the addition of −1 (11111110) to +2 (00000010).

    9gas0z.jpg


    In the previous example, the binary addition alone gives 00000000, which is incorrect. Only when the carry is added back in does the correct result (00000001) appear.

    mekanam gaththe WIKI walin, text book eke thiyena theory eka meeta wada amarui.

    Thank u vry much bro.............. :D