Computer Braille is an adaptation of
braille
Braille ( , ) is a Tactile alphabet, tactile writing system used by blindness, blind or visually impaired people. It can be read either on embossed paper or by using refreshable braille displays that connect to computers and smartphone device ...
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.
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. However, since January 2016 it is no longer official in the US and replaced by
Unified English Braille
Unified English Braille Code (UEBC, formerly UBC, now usually simply UEB) is an English language Braille code standard, developed to encompass the wide variety of literary and technical material in use in the English-speaking world today, in unifor ...
(UEB). It employs only the 6-dot braille patterns to represent all printing code points of
ASCII
ASCII ( ), an acronym for American Standard Code for Information Interchange, is a character encoding standard for representing a particular set of 95 (English language focused) printable character, printable and 33 control character, control c ...
. It is virtually identical to
Braille ASCII
Braille ASCII (or more formally The North American Braille ASCII Code, also known as SimBraille) is a subset of the ASCII character set which uses 64 of the printable ASCII characters to represent all possible dot combinations in six-dot braill ...
, 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 () character is used as the shift indicator or modifier. Thus, (grave accent, 0x60) is represented by , where is assigned to (at sign, 0x40). In other words, either adds (for punctuation) or subtracts (for letters) 32 to or from the ASCII value of the following character. Unlike Braille ASCII (underscore, 0x5F) is represented by .
2) The Braille Computer Notation as defined by the
Braille Authority of the United Kingdom.
It uses 8-dot patterns to represent 256 different values so arbitrary byte data can be written in Braille.
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;
The dot-5 () character is used as a universal modifier.
The following table assumes the 8-bit data is encoding text in the
CP437 character set used on the IBM PC.
References
{{Braille
Braille