Extended Binary Coded Decimal Interchange Code
Extended Binary Coded Decimal Interchange Code
(character, standard)EBCDIC is an extension to 8 bits of BCDIC (Binary CodedDecimal Interchange Code), an earlier 6-bit character set usedon IBM computers. EBCDIC was sed on the successfulSystem/360, anounced on 1964-04-07, and survived for manyyears despite the almost universal adoption of ASCIIelsewhere. Was this concern for backward compatibility or,as many believe, a marketing strategy to lock in IBMcustomers?
IBM created 57 national EBCDIC character sets and anInternational Reference Version (IRV) based on ISO 646 (andhence ASCII compatible). Documentation on these was noteasily accessible making international exchange of data evenbetween IBM mainframes a tricky task.
US EBCDIC uses more or less the same characters as ASCII,but different code points. It has non-contiguous lettersequences, some ASCII characters do not exist in EBCDIC(e.g. square brackets), and EBCDIC has some (cent sign,not sign) not in ASCII. As a consequence, the translationbetween ASCII and EBCDIC was never officially completelydefined. Users defined one translation which resulted in aso-called de-facto EBCDIC containing all the characters ofASCII, that all ASCII-related programs use.
Some printers, telex machines, and even electronic cashregisters can speak EBCDIC, but only so they can converse withIBM mainframes.
For an in-depth discussion of character code sets, and fulltranslation tables, see Guidelines on 8-bit character codes.
A history of character codes.
Here is a simple translation table:
Least significant nibble ->
0 1 2 3 4 5 6 7 8 9 A B C D E F0 ... controls ...123 ... controls ...4 ? ? ? ? ? ? ? ? ? . < ( + |5 & ? ? ? ? ? ? ? ? ? ! $ * ) ; ^6 - / ? ? ? ? ? ? ? ? ¦ , % _ > ?7 ? ? ? ? ? ? ? ? ? ` : # @ ' = "8 ? a b c d e f g h i « » ? ? ? ±9 ° j k l m n o p q r ? ? ? ? ? ¤A µ ~ s t u v w x y z ? ? ? [ ? ®B ¬ ? ? · © § ¶ ? ? ? ? ? ? ] ? ?C { A B C D E F G H I ? ? ? ? ?D } J K L M N O P Q R ? ? ? ? ? ?E \\ ? S T U V W X Y Z ? ? ? ? ? ?F 0 1 2 3 4 5 6 7 8 9 ? ? ? ? ?
E.g. the EBCDIC code for "A" is hexadecimal "C1".