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Background Data [ MPE XL Native Language Programmer's Guide ] MPE/iX 5.0 Documentation


MPE XL Native Language Programmer's Guide

Background Data 

EBCDIC is an 8-bit code that originally used only 128 of the 256 possible
code values.  These 128 characters have almost the same graphic
representations as the traditional 7-bit, 128-character, USASCII code.
Three characters are different.  USASCII has the left and right square
brackets ( [ and ] ) and the caret (^), while EBCDIC includes the
American cent (Â), the logical OR (|), and the logical NOT (-).

The EBCDIC code was modified to accommodate the extra characters required
by European languages.  For example, when the German EBCDIC was defined
some less important characters were traded for German national
characters, and the vertical bar (|) became lower case n.  Similar things
happened to create EBCDIC codes for Norwegian/Danish, Swedish/Finnish,
Spanish, Belgian, Italian, Portuguese, French, and English in the UK.

The 128 unused positions in the various national language EBCDIC codes
were later used to accommodate all national characters which appeared in
any of the EBCDIC codes.  Each resulting country extended code page
became a superset of each existing national EBCDIC. In the German table,
the empty space was used to accommodate characters from other languages,
but the traditional German characters (L, N, O, and beta) retained their
original position in the German national EBCDIC. There are many country
extended code pages now, all showing exactly the same characters, but
showing them in different locations for example, the character that has
decimal code 161 (octal 241, hexadecimal A1).  In original EBCDIC, it is
the ~ (tilde); in German, the sharp beta; in French, the 1/2 (diaeresis
accent); in Swedish/Finnish and Norwegian/Danish, the lower case -; in
Italian, the lower case i; and in Portuguese, the lower case c.

This situation makes it necessary to map the Hewlett-Packard ROMAN8
character set to the many different EBCDIC country extended code pages.



MPE/iX 5.0 Documentation