JIS X 0201

JIS X 0201 8-bit code page
MIME / IANA	8-bit:JIS_X0201 7-bit Roman:JIS_C6220-1969-ro 7-bit Kana:JIS_C6220-1969-jp
Alias(es)	JIS C 6220 8-bit: csHalfWidthKatakana Roman:ISO646-JP, iso-ir-14 Kana: iso-ir-13, x0201-7
Language(s)	Japanese (basic support),English
Standard	JIS X 0201:1969
Classification	ISO 646,Extended ISO 646
Preceded by	Wabun code, JIS C 0803
Succeeded by	Shift JIS
Other related encoding(s)	N-byte Hangul code
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JIS X 0201, aJapanese Industrial Standard developed in 1969, was the first Japanese electroniccharacter set to become widely used. The character set was initially known asJIS C 6220 before the JIS category reform. Its two forms were a 7-bit encoding or an 8-bit encoding, although the 8-bit form was dominant untilUnicode (specificallyUTF-8) replaced it. The full name of this standard is7-bit and 8-bit coded character sets for information interchange (7ビット及び8ビットの情報交換用符号化文字集合).

The first 96 codes comprise anISO 646 variant, mostly followingASCII with some differences, while the second 96 character codes represent the phonetic Japanesekatakana signs. Since the encoding does not provide any way to expresshiragana orkanji, it is only capable of expressing simplified written Japanese. Nevertheless, this simplification can represent the full range of sounds in the language. In the 1970s, this was acceptable for media such as text modecomputer terminals,telegrams, receipts, or other electronically handled data.

JIS X 0201 was supplanted by subsequent encodings such asShift JIS, which combines this standard andJIS X 0208, and later byUnicode.

TheComite Consultatif International Telephonique et Telegraphique (CCITT) introduced theInternational Telegraph Alphabet No.2 (ITA2) code as an international standard, which was the 5-bit Latin encoding. Most countries have their own national standards based on this. In Japan, the Agency of Industrial Science and Technology (AIST) standardized it as the 6-bit character codes of JIS C 0803-1961 (Keyboard layout and codes for teleprinters), which combined with katakana characters. However, it didn't match the industry requirements because the character map was small, and the code layout was impractical. The AIST considered a practical character encoding to replace various codes used in Japan.^[1]

In 1963,ISO introduced a draft of ISO R 646 (6 and 7-bit coded character sets for information processing interchange). AIST committed the conjunction of ISO R 646 and katakana mapping to theInformation Processing Society of Japan (IPSJ). IPSJ formed the code standardization committee. The committee didn't adopt the 6-bit form of ISO's draft because the katakana set couldn't fit into its character map. The early JIS draft mapped small katakana characters next to each of their normal katakana characters. It was considered to be convenient for sorting byGojūon order (JIS X 0208:1978 chose this ordering). Some committee members criticized it would complicate the mechanic of keyboards which only handled normal katakana characters. The later draft mapped small katakana characters to positions0xA7-0xAF.

The 1964 ISO draft reserved the positions0x24 and0x5c for first and second currency symbols to be assigned by each country, but it was considered too dangerous in international communications to use currency symbols that could be localized. The ISO committee had two options that to use ageneric currency symbol (¤) or to give thedollar ($) andpound (£) signs permanent assignments. It was agreed that the dollar sign was assigned to position0x24 and the pound sign was to position0x23. The latter was not required in countries that did not need the pound sign.^[2] The JIS committee decided to put theyen sign (¥) in0x5c (one of national use positions).

JIS C 6220 (Codes for information interchange, 情報交換用符号) was published in 1969. Its number was changed to JIS X 0201 due to the JIS category reform in 1987, and the name was changed to7-bit and 8-bit coded character sets for information interchange (7ビット及び8ビットの情報交換用符号化文字集合) in the 1990 edition.

The character set of JIS X 0201 had been widely used in Japan. The Nationwide Banking Data Communication System (全国銀行データ通信システム), the largest funds transfer system in Japan, was established in 1973. Transaction messages between banks used a subset of JIS X 0201. The system was used until 2018, and it was replaced by the ZEDI (The Nationwide Banking Electronic Data Interchange System, 全銀EDIシステム) which could handle hiragana and kanji characters.^[3] In 1978, the JIS C 6226 (JIS X 0208) 2-byte character set was developed to express hiragana and kanji characters. It includes katakana characters, but their codes and layout are different from JIS X 0201. Computer manufacturers developed their own extensions of JIS X 0208 to retain compatibility with JIS X 0201. In 1982, theMicrosoft Kanji encoding scheme (Codepage 932 ofMS-DOS) andDigital Research's SJC26 (for JapaneseCP/M-86) were developed to combine JIS X 0201 single-byte encoding and JIS X 0208 double byte encoding withoutshift out andshift in characters.^[4] They were calledShift JIS, which became the industrial standard for personal computers.

The first half (Roman set) of JIS X 0201 constitutes a Japanese variant ofISO 646, amounting toASCII withbackslash (\) andtilde (~) replaced byyen (¥) andoverline (‾),^[5] while the second half (Kana set) consists mainly ofkatakana.Control characters are specified inJIS X 0211.

In the 7-bit format, theshift out control character0x0E switches to the Kana set andshift in (0x0F) switches to the Roman set.^[6][7] In the 8-bit format, given in the chart below, bytes with the most significant bit set (i.e.0x80–0xFF) are used for the Kana set and bytes with it unset (i.e.0x00–0x7F) are used otherwise.

Names used specifically for the 7-bit Roman set include "JISCII",^[8] "JIS Roman",^[9] "ISO646-JP",^[10][11] "JIS C6220-1969-ro",^[11][10] "Japanese-Roman",^[12] "Japan 7-Bit Latin",^[13] and "ISO-IR-14",^[10][11][7] whereas names used specifically for the 7-bit Kana set include "ISO-IR-13",^[6][10][11] "JIS C6220-1969-jp"^[10][11] and "x0201-7".^[10][11]

The substitution of the yen symbol for backslash can make paths onDOS andWindows-based computers with Japanese support display strangely, like "C:¥Program Files¥", for example.^[14] Another similar problem isC programming language's control characters ofstring literals, likeprintf("Hello, world.¥n");.

The following table is the original 8-bit coded character set of JIS X 0201 (with the kana set indicated by bytes with the high bit set).^[15][16]

Following is the mapping used for JIS X 0201 as part ofShift JIS,^[17][18] i.e. showing the 8-bit form of JIS X 0201, and mapping the Katakana characters to theHalfwidth and Fullwidth Forms block (which in turn derives itshalf width kana layout from JIS X 0201).

The basicISO-2022-JP profile does not permit the Kana set of JIS X 0201, only the Roman set andJIS X 0208 (although ISO 2022 / JIS X 0202 itself permits it). Accordingly, when converting JIS X 0201 katakana (or Unicodehalf-width kana, which use the same layout) to ISO-2022-JP, the following mapping or transformation is often used.^[20] This allows the kana to be converted to JIS X 0208.

In theory, this mapping is equally correct, as JIS X 0201 itselfdoes not specify display width, although in practice (and especially induospaced environments) JIS X 0201 is used for half-width katakana.

For ease of comparison with the chart above, the mapping is shown below over the JIS X 0201 katakana encoding and with the high bit set.

Code page 897 isIBM's implementation of the 8-bit form of JIS X 0201. It includes several additional graphical characters in theC0 control characters area, and the code points in question may be used as control characters or graphical characters depending on the context,^[23] similarly in concept toOEM-US, but with different graphical characters. The C0 rows are shown below. IBM also designate pure 8-bit JIS X 0201 without these control code replacements asCode page 1139.^[24] Another variant, including a smaller subset of these C0 replacement graphics (including only the box drawing characters in0x01–06, 0x10, 0x15–17 and 0x19 and the line/arrow characters in0x1B–1F), but using a different style of up-arrow (U+21E7 ⇧UPWARDS WHITE ARROW) at0x1C, is designatedCode page 1086.^[25]

IBM also implements the 7-bit Roman set of JIS X 0201 asCode page 895^[31] and the 7-bit Kana set asCode page 896 for use asISO 2022 orEUC-JP code-sets. Code page 896, in addition to standard JIS X 0201 assignments, defines five additional assignments, shown below.^[32] Although use of these extended characters is not permitted by the associatedCCSID 896,^[33] they are permitted by the alternative CCSID 4992.^[34]

IBM'sCode page 1041 is an extended version of Code page 897, encoding these five IBM extended^[35] characters in alternative locations which are compatible withShift JIS (respectively0x80, 0xA0, 0xFD, 0xFE and 0xFF).^[36]Code page 911, another extended 8-bit JIS X 0201 implementation (which uses the same C0 replacement graphics as Code page 1086) encodes the pound (sterling) sign (£) at0xE1, similarly to Code page 896 with the eight bit set, but differs by encoding the cent sign (¢) at0xE2 and the not-sign (¬) at0xE3.^[37]

IBM'sCode page 903 is encoded for use as the single byte component of certainsimplified Chinese character encodings,^[38] accompanying theASCII-basedCode page 904 used withtraditional Chinese encodings.^[39][40] Despite this, Code page 903 follows ISO 646-JP / the Roman half of JIS X 0201, in that it replaces the ASCII backslash0x5C (rather than the ASCII dollar sign0x24 as in GB 1988 /ISO 646-CN) with theyen/yuan sign. It also uses the same C0 replacement graphics as code page 897.^[41]Code page 1042 extends code page 903 with the pound (sterling) sign at0x80, and the not-sign, backslash and tilde at their Code page 1041 locations.^[42]

• 
  NEC PC-8001 (1979) character set as rendered in the 8×8 pixel font
• 
  NEC variant used on thePC98 series.
• 
  Hitachi variant used on theHD44780.

• Diagram of JIS X 0201 (as 7-bit code sets)

• Encodings of Japanese
• JIS standards
• Computer-related introductions in 1969

• CS1 Japanese-language sources (ja)
• Articles with short description
• Short description matches Wikidata
• Articles containing Japanese-language text