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2.6.1 American Standard Code for Information Interchange (ASCII)

        This is the most commonly used encoding scheme used to encode characters in the English language. The ASCII
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        (pronounced as askee) code is a 7-bit code. So, it can only codify 2 =128 different characters. The Extended ASCII is
        an eight-bit code that includes 256 characters and retains most of the ASCII codes. Extended Binary Coded Decimal
        Interchange Code is an 8-bit code developed by IBM for its mainframe computers.
        Table  2.10  shows  characters  and  their  ASCII  codes,  expressed  in  decimal  numbers.  Note  that  ASCII  code  for  the
        uppercase alphabet A is 65, and subsequent alphabets are assigned incrementally higher values. Thus, ASCII codes for
        the characters B, C, D, … are 66, 67, 68, … . Similarly, ASCII code for the lowercase alphabet a is 97, and subsequent
        alphabets are assigned incrementally higher values. Thus, ASCII codes for the characters b, c, d, … are 98,99,100, … .
        and ASCII code for the digit 0 is 48, and subsequent digits are assigned incrementally higher values. Thus, ASCII codes
        for the digits 1, 2, 3, … are 49, 50, 51, … .
                                                   Table 2.10: ASCII Codes














































        Example 49: Encode the string Age using ASCII encoding scheme.
        Ans:

          Letter         ASCII Value    7-bit ASCII code
            A                65            1000001
            g               103            1100101
            e               101            1100111

        So, ASCII code in binary for the word Age is 100000111001011100111.
        Example 50: The following data is encoded in ASCII code. Decode the data and write the equivalent characters.
        1001100        1001111       1100111       1101111


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