This list provides an inventory of character coding standards mainly before modern standards like ISO/IEC 646 etc. Some of these standards have been deeply involved in historic events that still have consequences. One notable example of this is the ITA2 coding used during World War II (1939–1945). The nature of these standards is not as common knowledge like it is for ASCII or EBCDIC or their slang names. While 8-bit is the de facto standard as of 2016,[citation needed in the past 5-bit and 6-bit were more prevalent or their multiple.
Code
Introduction
Width
Usage
Morse code
c. 1837–1840
varies
Electrical telegraphs
Baudot code / ITA1
1870
5 bits
Piano-like telegraph operation, SIGCUM cipher operation
Chinese telegraph code
1881
4 digits
Chinese telegraph communications
Murray code
1901
5 bits
Machine run telegraph operation using punched paper, moved optimization from minimal operator fatigue to minimal machinery wear
ITA2
1924[ 1]
5 bits
Teletypewrite, Telecommunications devices for the deaf (TDD), Telex , Amateur radio , Radioteletype (RTTY), Financial info by Deutsche Börse ,[ 2] Enigma machine and T52 during WWII
BCDIC
1928
6 bits
Introduced with the IBM card
FIELDATA
1956[citation needed
6/7 bits
Battlefield information (USA)
CDC display code
1963
6 bits
Control Data Corporation computers
DEC SIXBIT /ECMA-1
1963
6 bits
Digital Equipment
EBCDIC
1963
8 bits
IBM computers
ASCII
1963-06-17 (ASA X3.4-1963 )[ 3] [ 4] [ 5] [ 6]
7 bits
Teleprinters and computers; original definition of ASCII
GOST 10859
1964
4/5/6/7 bits
Soviet Union
ECMA-6
1965-04-30
7 bits
ASCII localization
ISO 646
1967 (ISO/R646-1967 )[ 3]
7 bits
ASCII localization
ASCII
1967 (USAS X3.4-1967 )[ 3] [ 7] [ 6]
7 bits
Close to "modern" definition of ASCII
Transcode
1967
7 bits
IBM data transmission terminal 2780 , 3780
Recommendation V.3 IA5
1968
7 bits
MARC-8
1968
7 bits
Library computer systems
Braille ASCII
1969
6/7 bits
Tactile print for blind persons
JIS X 0201
1969
6/7 bits
First Japanese electronic character set
ECMA-48
1972
7 bits
Terminal text manipulation and colors
ISO/IEC 8859
1987
8 bits
International codes
ISO/IEC 10646 (Unicode )
1991
21 bits usable, packed into 8/16/32-bit code units
Unified encoding for most of the world's writing systems . As first introduced in 1991 had 16 bits; extension to 21 bits came later.
KPS 9566
1993
North Korean 2-byte character code set
See also
References
^ "BruXy: Radio Teletype communication" . 2005-10-10. Retrieved 2016-05-09 . The transmitted code use International Telegraph Alphabet No. 2 (ITA-2) which was introduced by CCITT in 1924. ^ "Enhanced Broadcast Solution – Interface Specification Final Version" (PDF) . Deutsche Börse . 2010-05-17. Retrieved 2011-08-10 .^ a b c Mackenzie, Charles E. (1980). Coded Character Sets, History and Development (PDF) . The Systems Programming Series (1 ed.). Addison-Wesley Publishing Company, Inc. ISBN 978-0-201-14460-4 LCCN 77-90165 . Archived (PDF) from the original on May 26, 2016. Retrieved August 25, 2019 . ^ "American Standard Code for Information Interchange, ASA X3.4-1963" . American Standards Association (ASA). 1963-06-17. Archived from the original on 2016-05-26. Retrieved 2014-05-23 .^ Winter, Dik T. (2010) [2003]. "US and International standards: ASCII" . Archived from the original on 2010-01-16. ^ a b Salste, Tuomas (January 2016). "7-bit character sets: Revisions of ASCII" . Aivosto Oy. urn :nbn:fi-fe201201011004 . Archived from the original on 2016-06-13. Retrieved 2016-06-13 . ^ USA Standard Code for Information Interchange, USAS X3.4-1967 . United States of America Standards Institute (USASI). July 7, 1967.
External links
