In 1990 the released a supplementary character set standard: JIS X 0212-1990 Code of the Supplementary Japanese Graphic Character Set for Information Interchange. This standard was intended to build upon the range of characters available in the main JIS X 0208 character set, and to address shortcomings in the coverage of that set.
Features
The standard specified 6,067 characters, comprising:
The following encodings or encapsulations are used to enable JIS X 0212 characters to be used in files, etc.
in EUC-JP characters are represented by three bytes, the first being 0x8F, the following two in the range 0xA1 – 0xFE.
in ISO 2022 the sequence "ESC $ ( D" is used to indicate JIS X 0212 characters.
No encapsulation of JIS X 0212 characters in the popular Shift JIS encoding is possible, as Shift JIS does not have sufficient unallocated code space for the characters.
Implementations
JIS X 0212 is called Code page 953 by IBM, which includes vendor extensions. The alternative CCSID5049 excludes these extensions. As JIS X 0212 characters cannot be encoded in Shift JIS, the coding system which has traditionally dominated Japanese information processing, few practical implementations of the character set have taken place. As mentioned above, it can be encoded in EUC-JP, which is commonly used in Unix/Linux systems, and it is here that most implementations have occurred:
an IME conversion file was compiled for the WNN system;
the :ja:Kterm|kterm console window application was extended to support it;
the Emacs and jstevie editors were extended to support it.
Many WWW browsers such as the Netscape/Mozilla/Firefox family, Opera, etc. and related applications such as Mozilla Thunderbird support the display of JIS X 0212 characters in EUC-JP encoding, however Internet Explorer has no support for JIS X 0212 characters. Modern terminal emulation packages, such as the GNOME Terminal also support JIS X 0212 characters. Applications which support JIS X 0212 in the EUC coding include:
The kanji in JIS X 0212 were taken as one of the sources for the Han unification which led to the unified set of CJK characters in the initial ISO 10646/Unicode standard. All the 5,801 kanji were incorporated.
The future
Apart from the applications mentioned above, the JIS X 0212 standard is effectively dead. 2,743 kanji from it were included in the later JIS X 0213 standard. In the longer term, its contribution will probably be seen to be the 5,801 kanji which were incorporated in Unicode.