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
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.
|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|
|14||016||0E||00001110||SO||Shift Out / X-On|
|15||017||0F||00001111||SI||Shift In / X-O|
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.
|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||/|