The Korean standard KSC 5601-1987 (formerly KIPS, updated in 1989 and 1992) has the following rows:
The KSC 5636 set is the Korean extension of ISO 646. It differs from US-ASCII only in having a Won sign in place of the backslash (5C).
The few hanja that have more than one pronunciation have extra codes, so that the 4888 hanja codes cover 4620 unique hanja.
The revisions did not alter the code assignments, only some annexes relating to alternative coding methods. Annex 3 of KSC 5601-1992 describes the 2-byte johab-hyeong code for modern Hangul syllables. This is a 16-bit code, with the top bit usually set, and then 5 bits each for
giving a total of 11,172 possible syllable blocks. Annex 4 describes a one-byte code for internal use.
KSC 5657-1991 has the following rows: