Editing Extended Unix Code (section)

===Adaptations of EUC-JP for EBCDIC===
{{Main article|Japanese language in EBCDIC}}

KEIS (Kanji-processing Extended Information System) is an [[EBCDIC]] encoding used by [[Hitachi]],<ref name="lunde2009appE" /> with double-byte characters (a DBCS-Host encoding) included using shifting sequences, making it a [[state (computer science)|stateful]] encoding. Specifically, the sequence {{code|0x0A 0x41}} switches to single-byte mode and the sequence {{code|0x0A 0x42}} switches to double-byte mode.{{efn|These sequences match the hexadecimal forms shown by DEC{{refn|name=decunix}} and the decimal forms ({{code|10 65}} and {{code|10 66}}) listed by Lunde.{{refn|name=lundeF}} Lunde lists the hexadecimal forms for both as {{code|0xA0 0x42}}, seemingly in error.}} However, JIS X 0208 characters are encoded using the same byte sequences used to encode them in EUC-JP. This results in duplicate encodings for the {{ctrl|IDSP|ideographic space}}—0x4040 per the DBCS-Host code structure, and 0xA1A1 as in EUC-JP. This differs from IBM's DBCS-Host encoding for Japanese, the layout of which builds on versions which predate JIS X 0208 altogether. The lead byte range is extended back to 0x59, out of which the lead bytes 0x81–A0 are designated for user-defined characters,<ref name="lundeF" /> and the remainder are used for corporate-defined characters, including both kanji and non-kanji.<ref name="lunde2009appE" />

JEF (Japanese-processing Extended Feature)<ref name="lunde2009appE" /> is an EBCDIC encoding used on [[Fujitsu]] FACOM mainframes, contrasting with FMR (a variant of Shift&nbsp;JIS) used on Fujitsu PCs. Like KEIS, JEF is a stateful encoding, switching to a double-byte DBCS-Host mode using shifting sequences (where {{code|0x29}} switches to single-byte mode and {{code|0x28}} switches to double-byte mode).<ref name="decunix">{{cite web |url=https://www.itec.suny.edu/scsys/unix/doc/V4.0F/docs/html/SUPPDOCS/JAPANDOC/JAPANCH2.HTM |title=2: Codesets and Codeset Conversion |work=DIGITAL UNIX Technical Reference for Using Japanese Features |publisher=[[Digital Equipment Corporation]], [[Compaq]] }}{{dead link|date=November 2023}}</ref> Also similarly to KEIS, {{nowrap|JIS X 0208}} codes are represented the same as in EUC-JP.<ref name="lundeF" /> The lead byte range is extended back to 0x41, with 0x80–0xA0 designated for user definition; lead bytes 0x41–0x7F are assigned row numbers 101 through 163 for [[kuten]] purposes, although row 162 (lead byte 0x7E) is unused.<ref name="lundeF" /><ref name="lunde2009appE" /> Rows 101 through 148 are used for extended kanji, while rows 149 through 163 are used for extended non-kanji.<ref name="lunde2009appE" />