Page 62 - ComputerScience_Class_11

Advantages of ASCII code are as follows:
• It is universally accepted. Unicode coding which has now replaced ASCII coding is compatible with it.
• It has a character encoding system.
• The codes for letters and digits are well adapted to different programming languages.

Disadvantage of ASCII code is as follows:
• It has a limited character set which can represent only the English language but is incapable of representing other
languages of the world.
To eliminate this drawback, ASCII 8 character encoding was introduced in 1980 which was an extended version of
8
ASCII 7. It could represent 2 or 256 characters (ranging from 0 to 255) which included letters used in other European
countries like Latin, graphics, signs, etc.

2.1.3 Indian Script Code for Information Interchange (ISCII)
Introduced in 1991 by the Bureau of Indian standards, this encoding scheme was designed to represent the character
set of different Indian languages. It follows an 8-bit encoding schema containing 256 characters. The first 128 characters
(0 to 127) are similar to the ASCII coding scheme.
Code points 128 to 255 represent basic characters from different Indian languages. Composite characters are formed
with the combination of these basic characters. The ISCII character code covers languages like Hindi, Bengali, Tamil,
Telugu, Kannada, Malayalam, Assamese, Oriya, Gujarati and Punjabi.
In addition to the code points representing characters, ISCII makes use of ATR (Attribute Code) followed by byte code
to change different font attributes or switch different ISCII languages as shown in the tables given below:

Change in formatting attributes
ATR + byte Mnemonic Font attributes
0 × 30 BLD Makes text bold
0 × 31 ITA Makes text italics
0 × 32 UL Underlines text
0 × 34 HLT Highlights text
0 × 35 OTL Outlines text
Change in ISCII scripts

ATR + byte Mnemonic Font attributes
0 × 42 DEV Devanagari
0 × 43 BNG Bengali
0 × 44 TML Tamil
0 × 45 TLG Telugu
0 × 46 ASM Assamese
0 × 47 ORI Odia
0 × 48 KND Kannada
0 × 49 MLM Malayalam
0 × 4A GJR Gujarati
0 × 4B PNJ Gurmukhi

Advantages of the ISCII code are as follows:
• Most of the Indian languages can be represented by this code.
• The character set is simple and easy to understand.
• Transliteration between different Indian languages is very easy.

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