Alphanumeric Codes

Alphanumeric codes are a combination of alphabetical and numerical characters, and is used to describe the collection of Latin letters and Arabic digits or a text constructed from this collection. Merriam-Webster suggests that the term “alphanumeric” may often additionally refer to other symbols, such as punctuation and mathematical symbols.

Alphanumeric codes are sometimes called character codes due to their certain properties. Now these codes are basically binary codes. We can write alphanumeric data, including data, letters of the alphabet, numbers, mathematical symbols and punctuation marks by this code which can be easily understandable and can be processed by the computers. Input output devices such as keyboards, monitors, mouse can be interfaced using these codes. 12-bit Hollerith code is the better known and perhaps the first effective code in the days of evolving computers in early days. During this period punch cards were used as the inputting and outputting data. But nowadays these codes are termed obsolete as many other modern codes have evolved. The most common alphanumeric codes used these days are ASCII code, EBCDIC code and Unicode.

Types of alphanumeric codes

ASCII Code

The full form of ASCII code is American Standard Code for Information Interchange. It is a seven bit code based on the English alphabet. In 1967 this code was first published and since then it is being modified and updated. ASCII code has 128 characters some of which are enlisted below to get familiar with the code.

DEC OCT HEX BIN Symbol Description
0 000 00 00000000 NUL Null char
1 001 01 00000001 SOH Start of Heading
2 002 02 00000010 STX Start of Text
3 003 03 00000011 ETX End of Text
4 004 04 00000100 EOT End of Transmission
5 005 05 00000101 ENQ Enquiry
6 006 06 00000110 ACK Acknowledgment
7 007 07 00000111 BEL Bell
8 010 08 00001000 BS Back Space
9 011 09 00001001 HT Horizontal Tab
10 012 0A 00001010 LF Line Feed
11 013 0B 00001011 VT Vertical Tab
12 014 0C 00001100 FF Form Feed
13 015 0D 00001101 CR Carriage Return
14 016 0E 00001110 SO Shift Out / X-On
15 017 0F 00001111 SI Shift In / X-O

EBCDIC Code

The EBCDIC stands for Extended Binary Coded Decimal Interchange Code. IBM invented this code to extend the Binary Coded Decimal which existed at that time. All the IBM computers and peripherals use this code. It is an 8 bit code and therefore can accommodate 256 characters. Below is given some characters of EBCDIC code to get familiar with it.

Char EBCDIC HEX Char EBCDIC HEX Char EBCDIC HEX
A 1100 0001 C1 P 1101 0111 D7 4 1111 0100 F4
B 1100 0010 C2 Q 1101 1000 D8 5 1111 0101 F5
C 1100 0011 C3 R 1101 1001 D9 6 1111 0110 F6
D 1100 0100 C4 S 1110 0010 E2 7 1111 0111 F7
E 1100 0101 C5 T 1110 0011 E3 8 1111 1000 F8
F 1100 0110 C6 U 1110 0100 E4 9 1111 1001 F9
G 1100 0111 C7 V 1110 0101 E5 blank
H 1100 1000 C8 W 1110 0110 E6 .
I 1100 1001 C9 X 1110 0111 E7 (
J 1101 0001 D1 Y 1110 1000 E8 +
K 1101 0010 D2 Z 1110 1001 E9 $
L 1101 0011 D3 0 1111 0000 F0 *
M 1101 0100 D4 1 1111 0001 F1 )
N 1101 0101 D5 2 1111 0010 F2
O 1101 0110 D6 3 1111 0011 F3 /