RFC 1554 (rfc1554) - Page 2 of 6

ISO-2022-JP-2: Multilingual Extension of ISO-2022-JP

RFC 1554         Multilingual Extension of ISO-2022-JP     December 1993


   The following table gives the escape sequences and the character sets
   used in "ISO-2022-JP-2" messages. The reg# is the registration number
   in ISO's registry [ISOREG].

                              94 character sets
      reg#  character set      ESC sequence                designated to
      ------------------------------------------------------------------
      6     ASCII              ESC 2/8 4/2      ESC ( B    G0
      42    JIS X 0208-1978    ESC 2/4 4/0      ESC $ @    G0
      87    JIS X 0208-1983    ESC 2/4 4/2      ESC $ B    G0
      14    JIS X 0201-Roman   ESC 2/8 4/10     ESC ( J    G0
      58    GB2312-1980        ESC 2/4 4/1      ESC $ A    G0
      149   KSC5601-1987       ESC 2/4 2/8 4/3  ESC $ ( C  G0
      159   JIS X 0212-1990    ESC 2/4 2/8 4/4  ESC $ ( D  G0

                              96 character sets
      reg#  character set      ESC sequence                designated to
      ------------------------------------------------------------------
      100   ISO8859-1          ESC 2/14 4/1     ESC . A    G2
      126   ISO8859-7(Greek)   ESC 2/14 4/6     ESC . F    G2

   For further information about the character sets and the escape
   sequences, see [ISO2022] and [ISOREG].

   If there is any G0 designation in text, there must be a switch to
   ASCII or to JIS X 0201-Roman before a space character (but not
   necessarily before "ESC 4/14 2/0" or "ESC N ' '") or control
   characters such as tab or CRLF.  This means that the next line starts
   in the character set that was switched to before the end of the
   previous line.  Though the designation to JIS X 0201-Roman is allowed
   for backward compatibility to "ISO-2022-JP", its use is discouraged.
   Applications such as pagers and editors which randomly seek within a
   text file encoded with "ISO-2022-JP-2" may assume that all the lines
   begin with ASCII, not with JIS X 0201-Roman.

   At the beginning of a line, information on G2 designation of the
   previous line is cleared.  New designation must be given before a
   character in 96 character sets is used in the line.

   The text must end in ASCII designated to G0.

   As the "ISO-2022-JP", and thus, "ISO-2022-JP-2", is designed to
   represent English and modern Japanese, left-to-right directionality
   is assumed if the text is displayed horizontally.

   Users of "ISO-2022-JP-2" must be aware that some common transport
   such as old Bnews can not relay a 7-bit value 7/15 (decimal 127),
   which is used to encode, say, "y with diaeresis" of ISO 8859-1.



Ohta & Handa