CCCII and ANSI Z39.64-1989 (EACC)
CCCII was developed by the Chinese Character Analysis Group, based in Taiwan.
It is used in libraries there.
The 3 numbers making up a code are called plane, section and position.
A layer is a group of 6 consecutive planes.
There are 15 layers, representing parallel versions of the same characters.
The layers of CCCII are:
- traditional characters
- simplified characters
- other variant forms
- Japanese kanji from JIS C 6226
- Korean hanja (?)
Layout of first layer:
- graphic ASCII
- Chinese punctuation marks (35)
- Kangxi radicals (214)
- Chinese numerical marks (41), phonetic symbols (37)
- most frequently used hanzi (4808)
- next most frequently used hanzi (17,032)
- other hanzi (20,583)
Each group of hanzi is ordered by:
- Kangxi radical number
- count of residual strokes
- lexicographical stroke order on residue: dian3, heng2, shu4, pie3, na4.
Sections 1-15 of other layers are said to be user space.
- shifted JIS C 6226 kanji
- reserved for Korean KIPS
- reserved for supplementary Chinese characters
- reserved for non-chinese characters of CB2
ANSI Z39.64-1989 (RLIN East Asian Character Code Set, REACC or EACC) was
created by the Research Libraries Group (RLG) in collaboration with the
US Library of Congress and the Chinese Character Analysis Group.
It has been used by the Library of Congress and other libraries
(mainly in North America) since 1983.
(Perhaps EACC and REACC denote slightly different sets??)
The structure of the code is based on CCCII,
but there are a few differences:
- there is no "other hanzi" set.
- many rare characters and variants are omitted.
- there are some substitutions,
to further the "one character, one code" principle.
Characters that are now variants but used to have a life of their own
are coded as variants (e.g. simplified wan4 "10,000" or yun2 "cloud").
Also layer 2 is used mainly for official simplified forms,
rather that just any non-orthodox variant with fewer strokes.
- layer 13, plane 1 contains 293 additional codes to cover the rest of
JIS C 6226-1983 (mainly kana and kokuji).
- layer 14, plane 1 contains Korean hangul to cover
- layer 14, plane 2 contains 44 additional codes to cover the rest of
An ISO 2022 encoding of a 94x94x94-character set would use the
with an ID in the range 60-6F, but none seem to be registered.
Part of Notes on CJK Character Codes and Encodings.