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Ch.3 Number and Character Coding Systems - Coggle Diagram
Ch.3 Number and Character Coding Systems
3.1 Denary, Binary and Hexadecimal Number Systems
Binary : Computers use it for data representations and manipulations.
Hexadecimal : Programmers use it to communicate with computers.
Denary : We use it in our daily life for counting and calculation.
3.2 Number System Conversion
Binary to denary
Only digits 0 and 1 are used in the binary number system.
b. Hexadecimal to denary
In the hexadecimal number system,
the digits 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E and F are used.
A, B, C, D, E, F represent 10, 11, 12, 13, 14, 15 respectively.
3.3 Number Representation in Computer Systems
Bit(A-Z)
Byte(Vocab)
Word(Sentences)
3.4 Addition and Subtraction of Different Number Representations
Overflow Error
same sign
opposite sign
Byte(1024 times each unit)
Megabyte(MB)
Gigabyte(GB)
Kilobyte(KB)
Terabyte (TB)
Byte (B)
Bit (b)
Signed Binary Integer
Sign-and-magnitude
Two’s Complement
3.5 Character Coding Systems
American Standard Code for Information Interchange(ASCII)
Extended Binary Coded Decimal Interchange Code (EBCDIC)
Chinese Character Coding System
extended ASCII: 256 characters
more than 100000 Chinese characters
standard ASCII: 128 characters
Chinese character coding system represent in
2.Guo Biao (GB) code: simplified Chinese
3.unicode
Made up of four bytes
code points
100000 characters
These characters can be represented by a one-byte code point.
existing language
Big 5 code : traditional Chinese