Method of Interpreting ASCII Terminal Input for Protocol Emulation
Original Publication Date: 1988-Feb-01
Included in the Prior Art Database: 2005-Feb-14
This article relates to the processing of ASCII characters requiring ASCII to EBCDIC code conversion and protocol emulation. The 128 characters of the standard 7-bit ASCII character set are mapped to a maximum of 256 (8-bit) EBCDIC characters and several functions (hereinafter collectively referred to as image elements). Therefore, the ASCII character set must be extended such that some of the image elements are represented by sequences of ASCII characters. The program scanning the ASCII input character stream and doing the mapping treats the characters differently, depending on whether they occur as individual characters or as part of a character string. For this purpose, a structured (character string interpretation) table is used. The CSIT consists of a header, a main table and several subtables.