Code extension in ASCII

The American Standard Code for Information Interchange (ASCII) contains a number of control characters associated with the principle of code extension, that is, with the representation of information which cannot be directly represented by means of the characters in the Code. The manner of use of these characters has not previously been completely described. This paper presents a set of mutually consistent philosophies regarding code extension applications, and suggests a corollary set of doctrines for the application of the code extension characters. Distinctions are drawn between code extension and such other concepts as “graphic substitution” or “syntactic representation” which are often used to meet similar requirements. Also covered are certain topics which are not truly concerned with code extension but which are often linked with it in discussion on code applications. The material in this paper is equally applicable in principle to the (proposed) ISO international 7-bit code for information interchange.

View this article in the ACM Digital Library.