Computer Braille Code: Difference between revisions

Revision as of 00:59, 10 April 2023

Revision as of 01:18, 10 April 2023

Line 1:

{{Short description|Braille for representation of computer-related materials}}

'''Computer Braille''' is an adaptation of [[braille]] for precise representation of computer-related materials such as programs, program lines, computer commands, and filenames. Unlike standard 6-dot braille scripts, but like [[Gardner–Salinas braille codes]], this may employ the extended 8-dot braille patterns. The resulting 256 braille characters are assigned to the 256 characters of 8-bit computer encodings.

There are two standards of representation of computer code with braille:

1) The '''Computer Braille Code''' as defined by the [[Braille Authority of North America]].<ref>{{cite book|title=Computer Braille Code: 2000 Revision|date=2000|publisher=Braille Authority of North America|url=http://www.brailleauthority.org/cbc/cbc.html}}</ref> However, since January 2016 it is no longer official in the US and replaced by [[Unified English Braille]] (UEB). It employs only the 6-dot braille patterns to represent all printing code points of [[ASCII]] as well as many technical characters and commands. It is virtually identical to the [[Braille ASCII]], a system of representation of braille with ASCII characters, which goal is mirrored to the Computer Braille Code. To represent ASCII code points 0x60, 0x7B, 0x7C, 0x7D, 0x7E as well as capital letters the 4-5-6 ({{braille cell|456}}) character is used as the shift indicator or modifier. Thus, {{code|`}} (grave accent, 0x60) is represented by {{braille cell|456|4}}, where {{braille cell|4}} is assigned to {{code|@}} (at sign, 0x40). In other words, {{braille cell|456}} either adds (for punctuation) or subtracts (for letters) 32 to or from the ASCII value of the following character. Unlike Braille ASCII {{code|_}} (underscore, 0x5F) is represented by {{braille cell|456|456}}.

{|{{chset-table-header1|Computer Braille Code}}

Line 117:

|}

2) The '''Braille Computer Notation''' as defined by the [[Braille Authority of the United Kingdom]].<ref>{{cite book|title=Braille Computer Notation|date=2006|publisher=Braille Authority of the United Kingdom (Computer Committee)|url=http://www.ukaaf.org/wp-content/uploads/2015/05/Braille-Computer-Notation-PDF.pdf|archive-url=https://web.archive.org/web/20200801050601if_/https://www.ukaaf.org/wp-content/uploads/2015/05/Braille-Computer-Notation-PDF.pdf|archive-date=2020-08-01|url-status=dead}}</ref> InIt this notation both 6- anduses 8-dot patterns mayto berepresent used.256 Withdifferent thevalues 6-dotso codearbitrary variousbyte combinations of braille charactersdata can representbe manywritten technical,in mathematical and logical symbolsBraille. The {{braille cell|5}} {{code|dot 5}} character is used as a universal modifier.
The 8-dot code is designed that its 6-dot subset is identical to the 6-dot code. The remainder are assigned by the following rules:

:* adding dot 7 subtracts 32 from the ASCII value;

:* adding dot 8 adds 128 to the ASCII value;

:* adding dots 7 and 8 adds 96 to the ASCII value.

The dot-5 ({{braille cell|5}}) character is used as a universal modifier{{clarification needed}}.

The following table assumes the 8-bit data is encoding text in the [[CP437]] character set used on the IBM PC.

{|{{chset-table-header1|Braille Computer Notation}}