RFC 373 (rfc373) - Page 2 of 4
Arbitrary Character Sets
Alternative Format: Original Text Document
NWG/RFC# 373 JMC 14-JUL-72 12:41 11058
ARBITRARY CHARACTER SETS by John McCarthy
Therefore, I would like to suggest that the next step be to arbitrary
character sets. I suggest implementing this in the following way:
(1) There be established a registry of characters. Anyone can
register a new character. Each character has a unique number, 17 bits
should be enough even to include Chinese. Besides this, each
character has a name in ASCII usually mnemonic. Finally, the
character has a design which is a picture on a 50 by 50 dot matrix.
(2) Besides the registry of characters, there is a registry of
characters sets, which different groups are using for different
classes of documents. A registered character set has a registry
number and a table giving the correspondence between the character
codes as bit sequences and the registered character numbers.
(3) Associated with a document is a statement of the character code
used therein. This may be one of the registered codes or it may
contain in addition modifications described by an auxiliary table
giving the code correspondence with registered character numbers. A
character code may have an escape character that says that the next
character is described by its registry number. The statement of the
character code may be a header on the document or the receiver may
have to learn it by some other means, e.g. because its library
catalog entry contains this information.
(4) Devices such as printers and displays draw characters in different
ways and standardization doesn't seem feasible at present. Therefore,
it is necessary to provide a way of going from the standard
description of a character using a 50 by 50 dot matrix to whatever
method the device uses. This is up to the programmers who are
supporting the device. Some may choose to manually create files
describing how registered characters are implemented. They may find
it too much work to provide for all the characters and to update their
files when new characters are registered. Others will provide
programs for going from the registered descriptions to descriptions
compatible with their implementations. Perhaps most will hand tailor
the characters most used and provide a program for the others.