PPT On COMPUTER CODES

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COMPUTER CODES Presentation Transcript:
1.COMPUTER CODES

2.COMPUTER CODES
Computer use binary coding schemes to represent data internally.
A group of bits represents every symbol that appears in the data.
Group of bits used to represent a symbol is called a “byte”.
1 byte=8 bits

3.TYPES OF CODESBCD CODE
EBCDIC
ASCII
UNICODE

4.BCD CODE
In computing and electronic systems, binary-coded decimal (BCD) is a class of binary encodings of decimal numbers where each decimal digit is represented by a fixed number of bits, usually four or eight, although other sizes (such as six bits) have been used historically.
Special bit patterns are sometimes used for a sign or for other indications

5.BCD CODE

6.EBCDIC
Extended Binary Coded Decimal Interchange Code (EBCDIC) is an 8-bit character encoding used mainly on IBM mainframe and IBM midrange computer operating systems.
EBCDIC descended from the code used with punched cards and the corresponding six bit binary-coded decimal code used with most of IBM's computer peripherals of the late 1950s and early 1960s.

7.ASCII
The American Standard Code for Information Interchange (ASCII) is a character-encoding scheme originally based on the English alphabet that encodes 128 specified characters - the numbers 0-9, the letters a-z and A-Z, some basic punctuation symbols, some control codes that originated with Teletype machines, and a blank space - into the 7-bit binary integers.

8.ASCII codes represents text  in computers , communication  equipments  and other devices that uses text.
ASCII includes definitions for 128 characters: 33 are non-printing control characters (many now obsolete) that affect how text and space are processed and 95 printable characters, including the space (which is considered an invisible graphic).

9.UNICODE
Unicode provides a unique number for every character, no matter what the platform, no matter what the program, no matter what the language.
Allows for multilingual text using any or all the languages you desire.

10.BENEFITS UNICODE
Having just one way to process text reduces development and support costs, improves time-to-market, and allows for single version of source code.
Standards insure interoperability and portability by prescribing conformant behavior.
Easy conversion from legacy code pages.

11.UNICODE ENCODING FORMS
UTF-8(Unicode Transformation Format-8)
UTF-16(Unicode Transformation Format-16)
UTF-32(Unicode Transformation Format-32)

12.UTF-8
This is byte oriented format having all Unicode characters represented as a variable length of one, two, three, or four bytes.

13.UTF-16
This is word oriented format having all Unicode characters represented as a variable length encoding of one or two words.(1 word=16 bits)

14.UTF-32
This is a double-word oriented format having all unicode characters represented as a fixed length encoding of two words.