trying to understand the relationship between the Version 1 Hangul syllables and the later versions'

[Ken Whistler]

No, there were in fact round-trip mappings defined (and used)
at the time. See, e.g.:

http://www.unicode.org/Public/MAPPINGS/OBSOLETE/EASTASIA/KSC/OLD5601.TXT

which shows the Unicode 1.1 <--> KS C 5601-1987 mappings for
the old range of Unicode 1.1 Hangul syllables 3400..3D2D.

http://www.unicode.org/Public/MAPPINGS/OBSOLETE/EASTASIA/KSC/KSC5601.TXT

shows the updated mappings for the complete johab set for Unicode 2.0
to an EUC encoding of KS C 5601-1992.

I'm not sure about the details of the implementation of KS C 5657-1991.
Somebody more familiar with the churn in Korean standards from
the early 1990's might know, however.

--Ken

On 6/24/2015 1:03 PM, Karl Williamson wrote:
> On 06/19/2015 04:12 PM, Ken Whistler wrote:
>>
>>
>> The Unicode 2.0 set of 11,172 was known as the "Johab" set from KS C
>> 5601-1992.
>> That was an algorithmically designed replacement of the earlier sets 
>> from
>> Korean standards -- designed to cover all modern syllables 
>> algorithmically,
>> by putting all the combinations of initial, medial and final jamos in a
>> defined
>> alphabetical order, whether or not each syllable that resulted was 
>> actually
>> attested in modern Korean use or not.
>
> Does this mean the original 2 standards (KS C 5601-1987 and KS C 
> 5657-1991) fell into disuse (or perhaps never were actually used) so 
> there was no need to map the new code points to them (hence no 
> round-trip defined)?
>>