ISO character sets, variant numbers
Various extended character sets for various language areas are standardized in ISO 8859, for example ISO 8859-1, ISO 8859-2, etc. The numbers at the end (-1, -2, etc.) are called the variant numbers. An extended character set contains all the characters required to represent the language of a language area.
ISO 8859 codes are extensions of the ASCII code ISO 646. They are used by terminals and Unix, Linux or Windows systems, for example. All ISO 8859 character sets contain the ASCII code as the shared part in the low-order half of the code table.
In addition there are the Unicode character sets UTF-8 and UTF-16 with which the characters of all language areas can be represented with a single character set.
EBCDIC character sets
EBCDIC character sets are used in the BS2000 operating system. An extension of EBCDIC.DF.03-IRV or -DRV exists for each ISO 8859 code. EBCDIC.DF.03-IRV is the international reference version and EBCDIC.DF.03-DRV is the German reference version of the non-extended EBCDIC code. Both codes contain the EBCDIC kernel as the shared character set and only differ in certain symbols. The extensions of these EBCDIC character sets are called EBCDIC.DF.04-1, EBCDIC.DF.04-2 through EBCDIC.DF.04-F.
The EBCDIC counterpart of ther Unicode character sets UTF-8 and UTF-16 is the character set UTF-EBCDIC (UTFE).
Compatible character sets
Extended ISO and EBCDIC character sets with the same variant number are compatible, i.e. they contain the same characters. The individual characters are located at different code positions within the code table. The codes can be transferred using conversion tables.
The BS2000 system administrator can use XHCS to modify the EBCDIC character sets by assigning different code positions in the code table to the individual characters of a character set. The complete set of characters is retained. The modified EBCDIC character sets are compatible with the EBCDIC.DF.04-n character set from which they were generated.
Reference code
XHCS combines all compatible character sets of the system into a group. A group therefore contains an ISO variant and the EBCDIC character sets compatible with this variant. The EBCDIC.DF.04-n character set of the group is the reference code of the group. All character sets in a group can be converted to the reference code of the group using XHCS.
Coded character set name (CCS name)
A name containing a maximum of eight characters, known as the CCS name or the CCSN, is assigned to each character set used in the system. The CCS name uniquely identifies the character set in the system. The CCS names of the reference codes are predefined by XHCS. EBCIDIC.DF.04-1 has the CCS name EDF041, for example.
A list of the CCS names for the character sets available in your BS2000 can be obtained using EDT. To request this information, call EDT and enter the EDT statement @SHOW CCS. EDT then supplies a list of the available character sets.
Default system code
The BS2000 system administrator can define several extended character sets (also for various ISO variants), which can be used simultaneously by the system components.
The system administrator can define one of these character sets as the default system code. The default system code currently set is indicated in the output of the command/SHOW-SYSTEM-PARAMETERS PAR=*AL. It is specified in the HOSTCODE parameter.
Default user character set
The BS2000 system administrator can assign one of the character sets defined in the system as the default user character set for each BS2000 user ID. If a default user character set is defined for the BS2000 user ID, its CCS name is displayed in the output field CODED-CHARACTER-SET of the /SHOW-USER-ATTRIBUTES command.