Computer Code: Computer codes are used to convert data into binary form to make the computer understand it. Apart from this, they are responsible for error-free signal flow in the computer. Three popular computer codes are:
BCD (Binary Coded Decimal): It is one of the earliest developed memory codes. In this, every digit is converted into binary form separately: e.g.,
But four-bit code can handle only 2 = 16 different characters that are why it is extended to 6-bit code and It can handle 2 = 64 different characters. It is 6-bit code and divided into two parts i.e., zone bit and character code. Zone bit consists of Z bits and character zone consists of 4 bits. To understand more look at the table given below:
EBCDIC (Extended Binary Coded Decimal Interchange Code): BCD can convert only 64 characters but we use more than 64 characters in computer to represent data. To overcome this problem, 2 more bits have been added to the zone bit to develop new 8- bit code and, that is why it is known as extended binary coded decimal interchange code. EBCDIC is 8- bit code which can encode 2 = 256 different characters. It is similar to BCD in working but it has 4 bits in bit zone. To understand more table is given below:
ASCII (American Standard Code for Information Interchange): This code is the most popular and widely accepted computer code. It is the standard code for computers, developed by the American National Standards Institute in the year 1963 for encoding different characters in the computer. It is used by almost every manufacturing company. ASCII codes are of two types: (a) 7-bit Code: To encode 2 = 128 characters with 3 bits in zone bit and four in character zone.
(b) 8-bit code: To encode 2 = 256 characters with 4 bits in bit zone and 4 bits in character zone.
