JEF is a stateful EBCDIC charset used in Fujitsu mainframe systems called FACOM and some OASYS series personal word processors. JEF is an acronym for "Japanese processing Extended Feature". It was introduced by Fujitsu in April 1979, but the implementation actually predates JIS C 6226-1978.
Here are the valid ranges of bytes according to its encoding structure.
|Byte Range Purpose
||Byte Range in Hexadecimal
||Includes graphic characters. Does not include unassigned characters nor ISO control characters.
|shift to single byte mode
|shift to double byte mode
|first byte of double byte
||40, 41-7D, 7F-FE
||A1-FE are JIS C 6226-1978 characters. 41-7D, 7F are extended characters. 80-A0 are user defined characters.
Byte 40 is only valid when followed by byte 40.
|second byte of double byte
||40 is only valid when preceded by byte 40. 0x40 0x40 makes the ideographic space character.
- Lunde, Ken. CJKV Information Processing. Sebastopol, Calif.: O'Reilly & Associates, 1998. ISBN 1-56592-224-7.