Editing ANSI escape code (section)

== History ==
Almost all manufacturers of video terminals added vendor-specific escape sequences to perform operations such as placing the cursor at arbitrary positions on the screen. One example is the [[VT52]] terminal, which allowed the cursor to be placed at an x,y location on the screen by sending the {{code|ESC}} character, a {{code|Y}} character, and then two characters representing numerical values equal to the x,y location plus 32 (thus starting at the ASCII space character and avoiding the control characters). The [[Hazeltine 1500]] had a similar feature, invoked using {{code|~}}, {{code|DC1}} and then the X and Y positions separated with a comma. While the two terminals had identical functionality in this regard, different control sequences had to be used to invoke them.

As these sequences were different for different terminals, elaborate libraries such as [[termcap]] ("terminal capabilities") and utilities such as [[tput]] had to be created so programs could use the same [[application programming interface|API]] to work with any terminal. In addition, many of these terminals required sending numbers (such as row and column) as the binary values of the characters; for some programming languages, and for systems that did not use ASCII internally, it was often difficult to turn a number into the correct character.

The ANSI standard attempted to address these problems by making a command set that all terminals would use and requiring all numeric information to be transmitted as ASCII numbers. The first standard in the series was '''ECMA-48''', adopted in 1976.<ref name="ECMA-48 (1979)" /> It was a continuation of a series of character coding standards, the first one being [[ECMA-6]] from 1965, a 7-bit standard from which [[ISO 646]] originates. The name "ANSI escape sequence" dates from 1979 when [[American National Standards Institute|ANSI]] adopted ANSI X3.64.  The ANSI X3L2 committee collaborated with the [[Ecma International|ECMA]] committee TC 1 to produce nearly identical standards. These two standards were merged into an international standard, ISO 6429.<ref name="ECMA-48 (1979)" /> In 1994, ANSI withdrew its standard in favor of the international standard.

[[File:DEC VT100 terminal.jpg|thumb|The DEC VT100 video display terminal.|alt=DEC VT100 terminal]]
The first popular video terminal to support these sequences was the [[Digital Equipment Corporation|Digital]] [[VT100]], introduced in 1978.<ref name="Williams_2006_VT"/> This model was very successful in the market, which sparked a variety of VT100 clones, among the earliest and most popular of which was the much more affordable [[Zenith Z-89|Zenith Z-19]] in 1979.<ref>{{cite web |url=http://www.pestingers.net/Computer_history/Computers_79.htm |title=Heathkit Catalog 1979 |author=Heathkit Company |date=1979 |publisher=Heathkit Company |access-date=2011-11-04 |url-status=dead |archive-url=https://web.archive.org/web/20120113230301/http://www.pestingers.net/Computer_history/Computers_79.htm |archive-date=2012-01-13}}</ref><!-- Document at http://www.retroarchive.org/hardware/heathkit/H19CODES.DOC shows that you "Enter ANSI mode" with ESC <, but does not document the result --><!-- H-19 Esc < switches into ANSI mode, requiring a proprietary ANSI extended escape code to return to VT52 (Heathkit) mode. ~~~~ -->  Others included the [[Qume]] QVT-108, [[Televideo]] TVI-970, [[Wyse]] WY-99GT as well as optional "VT100" or "VT103" or "ANSI" modes with varying degrees of compatibility on many other brands. The popularity of these gradually led to more and more software (especially [[bulletin board system]]s and other [[online service]]s) assuming the escape sequences worked, leading to almost all new terminals and emulator programs supporting them.

In 1981, ANSI X3.64 was adopted for use in the US government by [[Federal Information Processing Standards|FIPS]] publication 86.  Later, the US government stopped duplicating industry standards, so FIPS pub. 86 was withdrawn.<ref>{{cite web|url=https://www.nist.gov/system/files/documents/2016/12/15/withdrawn_fips_by_numerical_order_index.pdf|title=Withdrawn FIPS Listed by Number|date=15 December 2016|website=[[National Institute of Standards and Technology]]|access-date=2 January 2022}}</ref>

ECMA-48 has been updated several times and is currently at its 5th edition, from 1991.<ref>{{cite web |url=https://ecma-international.org/publications-and-standards/standards/ecma-48/ |title=ECMA-48 — Control functions for coded character sets|publisher=[[ECMA International]]}}</ref> It is also adopted by [[International Organization for Standardization|ISO]] and [[International Electrotechnical Commission|IEC]] as standard '''ISO/IEC 6429'''.<ref>{{cite ISO standard|csnumber=12782 |title= ISO/IEC 6429:1992 — Information technology — Control functions for coded character sets |publisher=[[International Organization for Standardization|ISO]]}}</ref> A version is adopted as a [[Japanese Industrial Standard]], as [[JIS X 0211]].

Related standards include [[ITU T.61]], the [[Teletex]] standard, and the '''ISO/IEC 8613''', the [[Open Document Architecture]] standard (mainly ISO/IEC 8613-6 or ITU T.416). The two systems share many escape codes with the ANSI system, with extensions that are not necessarily meaningful to computer terminals. Both systems quickly fell into disuse, but ECMA-48 does mark the extensions used in them as reserved.