eucTW - A character encoding system (codeset) for Traditional Chinese
The Taiwanese EUC (Extended UNIX Code), or eucTW, codeset consists of the following character sets: ASCII CNS 11643 (Plane 1 to Plane 16)
Taiwanese EUC uses a combination of single-byte data and 2-byte data to represent ASCII characters, symbols, and ideographic characters. Because too many character planes were included, Taiwanese EUC uses different leading codes to designate different character planes.
ASCII characters are represented in the form of single byte 7-bit data in Taiwanese EUC; that is, the most significant bit (MSB) of the byte that represents an ASCII character is always set off. For more information, refer to ascii(5).
Although the standard Taiwanese EUC codeset includes all characters defined by the CNS 11643-1992 standard, Digital's eucTW implementation currently supports the following: Characters defined in the first and second planes of CNS 11643 The EDPC Recommended Character Set (refer to dechanyu(5) for more information) CNS 11643-1986 and DTSCS characters that have been remapped into the third and fourth character planes by the CNS 11643-1992 standard
Characters that were added to CNS 11643-1986 by the CNS 11643-1992 standard are not supported.
The characters that are defined in plane 1 and plane 2 of CNS 11643-1992 and that are the same as those defined in CNS 11643-1986 are as follows:
|Character Plane||Character Type||Number of Characters|
|2||Less frequently-used characters||7650|
The characters defined in plane 3 and plane 4 of CNS 11643-1992 are as follows:
|Character Plane||Character Type||
Number of Characters
|3||Rarely-used characters (EDPC Part I)||6148|
|4||Used for residency system, ISO 2nd edition DIS 10646 Han characters, 171 EDPC Part II Characters||7298|
The characters that have been remapped into the third and fourth character planes of CNS 11643-1992 as specified by the EDPC are as follows:
|EDPC Characters||Character Plane||Number of Characters|
|Part I||Plane 3||6148|
|Part II||Plane 4||171|
Except for characters in the first plane of CNS 11643-1986, Taiwanese EUC makes use of a leading code (the 8-bit Single-Shift 2 control character (SS2) and an additional byte) to designate characters to a character plane.
The position of a character on a plane is specified by two bytes. The first byte determines the character's row number and the second byte determines the character's column number. The MSB of both bytes is set on.
The following table shows the encoding of Taiwanese EUC characters:
|CNS 11643-1986 Code Plane||Leading Code||Code Range|
|1||[nil]||A1A1 - FEFE|
|2||SS2 A2||A1A1 - FEFE|
|3||SS2 A3||A1A1 - FEFE|
|4||SS2 A4||A1A1 - FEFE|
|5||SS2 A5||A1A1 - FEFE|
|6||SS2 A6||A1A1 - FEFE|
|7||SS2 A7||A1A1 - FEFE|
|8||SS2 A8||A1A1 - FEFE|
|9||SS2 A9||A1A1 - FEFE|
|10||SS2 AA||A1A1 - FEFE|
|11||SS2 AB||A1A1 - FEFE|
|12||SS2 AC||A1A1 - FEFE|
|13||SS2 AD||A1A1 - FEFE|
|14||SS2 AE||A1A1 - FEFE|
|15||SS2 AF||A1A1 - FEFE|
|16||SS2 B0||A1A1 - FEFE|
The following codeset converter pairs are available for converting Traditional Chinese characters between eucTW and other encoding formats. Refer to iconv_intro(5) for an introduction to codeset conversion. For more information about the other codeset for which eucTW is the input or output, see the reference page specified in the list item. big5_eucTW, eucTW_big5
For both display devices and printers, the operating system supports Taiwanese EUC through internal conversion to DEC Hanyu code and use of DEC Hanyu fonts (see dechanyu(5)).
For general information on printing non-English text, refer to
Others: ascii(5), big5(5), Chinese(5), code_page(5), dechanzi(5), iconv_intro(5), i18n_intro(5), i18n_printing(5), l10n_intro(5), sbig5(5), telecode(5), Unicode(5)