CEN Guide to the Use of Character Sets in EuropeTC 304

8-bit Character Sets - ISO/IEC 4873

Current edition

ISO/IEC 4873:1991
Information technology - ISO 8-bit code for information interchange - Structure and rules for implementation (third edition).


This standard specifies a structure for 8-bit codes that builds on the general structure for such codes laid down in ISO/IEC 2022. In particular the content of the GL area of the code table is fully specified and the content of the GR area is restricted to be a character set that makes use of single-byte coding (and so contains at most 96 characters). The fixed content for the GL area is the set registered in the ISO 2375 Register as ISO-IR 6. This set is also the International Reference Version (IRV) of ISO/IEC 646:1991 and is more commonly known as the ASCII character set.

The code extension techniques permitted by ISO/IEC 4873 are only a selection of those specified by ISO/IEC 2022.

Tutorial guidance

ISO/IEC 4873 specifies three levels of implementation:

The coding of single shifts and locking shifts is given in the section of this guide on control functions.

A collection of coded graphic character sets suitable for use within the structure of ISO/IEC 4873 has been standardized in ISO/IEC 10367.

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