Several mutually incompatible versions of the Extended Binary Coded Decimal Interchange Code (

EBCDIC Extended Binary Coded Decimal Interchange Code (EBCDIC; ) is an eight- bit character encoding used mainly on IBM mainframe and IBM midrange computer operating systems. It descended from the code used with punched cards and the corresponding ...

) have been used to represent the

Japanese language is spoken natively by about 128 million people, primarily by Japanese people and primarily in Japan, the only country where it is the national language. Japanese belongs to the Japonic or Japanese- Ryukyuan language family. There have been ...

on computers, including variants defined by Hitachi, Fujitsu, IBM and others. Some are

variable-width encoding A variable-width encoding is a type of character encoding scheme in which codes of differing lengths are used to encode a character set (a repertoire of symbols) for representation, usually in a computer. Most common variable-width encodings ar ...

s, employing locking shift codes to switch between single-byte and double-byte modes. Unlike other EBCDIC locales, the lowercase basic Latin letters are often not preserved in their usual locations. The characters which are found in the double-byte Japanese code used with EBCDIC by IBM, but not found in the first edition of

JIS X 0208 JIS X 0208 is a 2-byte character set specified as a Japanese Industrial Standards, Japanese Industrial Standard, containing 6879 graphic characters suitable for writing text, place names, personal names, and so forth in the Japanese language. Th ...

, also influenced the vendor extensions found in some non-EBCDIC encodings such as IBM code page 932 ("DBCS-PC") and Windows code page 932.

Single-byte codes

Similarly to

JIS X 0201 JIS X 0201, a Japanese Industrial Standard developed in 1969 (then called JIS C 6220 until the JIS category reform), was the first Japanese electronic character set to become widely used. It is either a 7-bit encoding or an 8-bit encoding, altho ...

(itself incorporated into

Shift JIS Shift JIS (Shift Japanese Industrial Standards, also SJIS, MIME name Shift_JIS, known as PCK in Solaris contexts) is a character encoding for the Japanese language, originally developed by a Japanese company called ASCII Corporation in conjuncti ...

), Japanese EBCDIC encodings often include a set of single-byte

katakana is a Japanese syllabary, one component of the Japanese writing system along with hiragana, kanji and in some cases the Latin script (known as rōmaji). The word ''katakana'' means "fragmentary kana", as the katakana characters are derived f ...

. Several different variants of the single-byte EBCDIC code are used in the Japanese locale, by different vendors; a given vendor may also define two different single-byte codes, one favoured for half-width katakana and one favoured for

Latin script The Latin script, also known as Roman script, is an alphabetic writing system based on the letters of the classical Latin alphabet, derived from a form of the Greek alphabet which was in use in the ancient Greek city of Cumae, in southern I ...

. Variants of EBCDIC favoured by a given vendor for use for katakana are sometimes referred to as EBCDIK, standing for Extended Binary-Coded Decimal Interchange Kana code. Code pages incorporating half-width kana are an exception to IBM's EBCDIC invariant character set, which specifies a set of characters which are usually encoded the same across all EBCDIC code pages. Most notably, they sometimes include katakana characters at code points which are used for

lowercase Letter case is the distinction between the letters that are in larger uppercase or capitals (or more formally ''majuscule'') and smaller lowercase (or more formally ''minuscule'') in the written representation of certain languages. The writing ...

letters of the Basic Latin alphabet in the invariant set. Encoding of lowercase letters when katakana characters are included at those locations, and encoding of katakana characters when lowercase letters are retained in their usual locations, can vary between vendors, as shown below. Microsoft Windows implements two Japanese single-byte EBCDIC variants, with code page numbers 20000 higher than IBM's code page numbers for its variants, as code pages 20290 (documented as , "IBM EBCDIC Japanese Katakana Extended") and 21027 ("Extended/Ext Alpha Lowercase"). Code page 21027 as implemented in Windows is an incomplete implementation, lacking two-way mappings for several letters and kana, and is currently deprecated. IBM's code pages were later updated to include the Euro sign at 0xE1, retaining their original CPGID numbers, but being assigned new CCSID numbers. Hence, the CCSID 290 refers to the original version of code page 290, while the version of code page 290 with the Euro sign is also known as CCSID 8482. Similarly, CCSID 1027 refers to the original version of code page 1027, while the version of CPGID 1027 with the Euro sign is given the CCSID 5123. Alongside versions of IBM's double-byte Japanese DBCS-Host code page (CPGID 300, CCSID 300 or 16684) as a double-byte component, IBM code page 290 is used as the single-byte component of the multi-byte code page IBM-930 and (as the Euro-updated CCSID 8482) the updated version IBM-1390. IBM code page 1027 is used as the single-byte component of the multi-byte code page IBM-939 and (as the Euro-updated CCSID 5123) the updated version IBM-1399. In the following table, conformance to the invariant set is marked with green; collision with the invariant set is marked with red.

Double-byte codes

There are three double-byte character codes used for Japanese with EBCDIC: IBM code page 300 (also called IBM Kanji or IBM Japanese DBCS-Host) from IBM, KEIS from Hitachi, and JEF from Fujitsu. These are DBCS-Host encodings, using different shift codes to switch between single-byte EBCDIC and double-byte modes. Codes 0x41 through 0xFE (those used for graphic characters in EBCDIC) are used in pairs to represent characters from a 190×190 grid; code 0x40 (

space Space is the boundless three-dimensional extent in which objects and events have relative position and direction. In classical physics, physical space is often conceived in three linear dimensions, although modern physicists usually cons ...

in EBCDIC) is used doubled as an

ideographic space In computer programming, whitespace is any character or series of characters that represent horizontal or vertical space in typography. When rendered, a whitespace character does not correspond to a visible mark, but typically does occupy an area ...

, but not as part of any other double-byte code. In the IBM version of the DBCS-Host code, the code switches to single-byte mode and the code switches to double-byte mode, in common with IBM double-byte EBCDIC codes for other CJK languages, such as the EBCDIC version of

Johab KS X 1001, "''Code for Information Interchange (Hangul and Hanja)''", formerly called KS C 5601, is a South Korean coded character set standard to represent hangul and hanja characters on a computer. KS X 1001 is encoded by the most common leg ...

for

Korean Korean may refer to: People and culture * Koreans, ethnic group originating in the Korean Peninsula * Korean cuisine * Korean culture * Korean language **Korean alphabet, known as Hangul or Chosŏn'gŭl **Korean dialects and the Jeju language ** ...

. In contrast to KEIS and JEF, the layout of IBM code page 300 is unrelated to

, and conversion between the two must be done via a table; however, its character repertoire has been kept up-to-date with successive revisions of JIS X 0208 so as to remain a superset of JIS X 0208's repertoire. Lead bytes 0x41 through 0x44 are used for non-Kanji characters, lead bytes 0x45 through 0x68 are used for Kanji characters, and lead bytes 0x69 through 0x89 are used for UDC ( user-defined characters). The existence of IBM's Japanese DBCS-Host code had impact beyond EBCDIC systems, since IBM also defined variants of

("DBCS-PC", defined in the pure double-byte Code page 301 and used in the variable width Code page 932 and Code page 942) and of

EUC-JP Extended Unix Code (EUC) is a multibyte character encoding system used primarily for Japanese, Korean, and simplified Chinese. The most commonly used EUC codes are variable-length encodings with a character belonging to an compliant coded char ...

which encode the entire repertoire of IBM code page 300, including 28 non-Kanji and 360

Kanji are the logographic Chinese characters taken from the Chinese family of scripts, Chinese script and used in the writing of Japanese language, Japanese. They were made a major part of the Japanese writing system during the time of Old Japanese ...

additional to those originally included in JIS X 0208 (although the non-Kanji

because sign In logical argument and mathematical proof, the therefore sign, , is generally used before a logical consequence, such as the conclusion of a syllogism. The symbol consists of three dots placed in an upright triangle and is read ''therefore''. ...

∵ and

not sign In logic, negation, also called the logical complement, is an operation that takes a proposition P to another proposition "not P", written \neg P, \mathord P or \overline. It is interpreted intuitively as being true when P is false, and false ...

￢ were later added to JIS X 0208 in 1983). These are referred to as "IBM-selected" characters and are included as extensions in, for example, Windows code page 932. Some newer revisions of the IBM-300 code page add additional Kanji with lead bytes 0xB8 through 0xD5 and additional non-Kanji with lead bytes 0xD6 through 0xE9. This revision updated the set for

JIS X 0213 JIS X 0213 is a Japanese Industrial Standard defining coded character sets for encoding the characters used in Japan. This standard extends JIS X 0208. The first version was published in 2000 and revised in 2004 (JIS2004) and 2012. As well as a ...

, including the Euro sign and, while retaining the CPGID 300, was assigned the new CCSID 16684. The code pages IBM-930 (with code page 290 as the single-byte set) and IBM-939 (with code page 1027 as the single-byte set) exclude these additions, while IBM-1390 (with the Euro sign version of code page 290 / CCSID 8482) and IBM-1399 (with the Euro sign version of code page 1027 / CCSID 5123) include them. In Hitachi KEIS (Kanji-processing Extended Information System), the sequence switches to single-byte mode and the sequence switches to double-byte mode. JIS X 0208 characters are encoded using the same byte sequences used to encode them in

, i.e. with both bytes being between 0xA1 and 0xFE inclusive. This results in duplicate encodings for the —0x4040 per the DBCS-Host code structure, and 0xA1A1 as in EUC-JP. However, the lead byte range is extended back to 0x59, out of which the lead bytes 0x81–A0 are designated for user-defined characters, and the remainder are used for corporate-defined characters, including both kanji and non-kanji. In Fujitsu JEF (Japanese-processing Extended Feature), switches to single-byte mode and switches to double-byte mode. Similarly to KEIS, JIS X 0208 codes are represented the same as in EUC-JP. Differing from KEIS, the JIS X 0208 edition used in this JEF zone is the original JIS C 6226:1978. The lead byte range is extended back to 0x41, with 0x80–A0 designated for user definition; lead bytes 0x41–7F are assigned row numbers 101 through 163 for

kuten JIS X 0208 is a 2-byte character set specified as a Japanese Industrial Standard, containing 6879 graphic characters suitable for writing text, place names, personal names, and so forth in the Japanese language. The official title of the current ...

purposes, although row 162 (lead byte 0x7E) is unused. Rows 101 through 148 are used for extended kanji, while rows 149 through 163 are used for extended non-kanji.

Footnotes

References

{{Character encodings EBCDIC code pages Encodings of Japanese