RFC 338 (rfc338) - Page 2 of 6
EBCDIC/ASCII Mapping for Network RJE
Alternative Format: Original Text Document
RFC 338 EBCDIC/ASCII MAPPING FOR NETWORK RJE May 1972
special-purpose text composition programs, IBM 360 programs use only
the 89 "basic" EBCDIC graphics [5] shown in RFC #183 as well as in
Figure 1. An IBM 029 "EBCDIC" keypunch can create 63 graphics: the
89 basic EBCDIC graphics less the 26 lower case letters. In fact,
OS/360 requires an even smaller subset of EBCDIC, 60 characters
commonly called the "PL/1 character set". The PL/1 set consists of
the 89 basic graphics, less the 26 lower case letters as well as the
three graphics !" (cent sign, exclamation point, and
quotation).
C. CHARACTER MAPPING IN NETRJS
We consider now the requirements of a ASCII/EBCDIC mapping for NETRJS
or any rje protocol. These requirements are as follows:
Efficiency:
The translation should be character-to-character, so that the CPU
operation "translate" can be used and character scans obviated.
This is important because a significant volume of character data
may be moved during rje operations.
Usability:
(1) All of the 89 EBCDIC graphics should be mapped into
corresponding ASCII characters.
(2) The mapping should be as nearly transparent as possible, i.e.,
whenever the same graphic appears in both sets, it should map
onto itself.
(3) To minimize the adaptation required of an EBCDIC-oriented
programmer, the ASCII graphics should evoke the corresponding
EBCDIC graphic, when they are not identical.
Theses considerations led us to incorporate Winett's rules II (a) and
III (b) (see page 4 of the RFC #183) into NETRJS:
ASCII EBCDIC
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Braden