Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83 (MC840302); site erialfa.UUCP Path: utzoo!linus!philabs!cmcl2!seismo!mcvax!enea!erix!erialfa!kjelle From: kjelle@erialfa.UUCP (Kjell Eriksson) Newsgroups: net.internat Subject: On code extensions and ANSI. Message-ID: <110@erialfa.UUCP> Date: Wed, 13-Nov-85 01:09:49 EST Article-I.D.: erialfa.110 Posted: Wed Nov 13 01:09:49 1985 Date-Received: Fri, 15-Nov-85 20:59:01 EST Reply-To: kjelle@erialfa.UUCP (Kjell Eriksson) Organization: Ericsson Information Systems AB, Data Terminals Div, Kista, Sweden Lines: 35 Here is a very short summary of what the ANSI standars says on code extention. I hope it's correct. I'm sure you'll let me know if it isn't. ANSI X3.41-1974 (Code extension techniques for use with the 7-bit .... ASCII) and ANSI X3.64-1979 (Additional controls for .... ), on which the VT100 is based, provides for the following ways of extending the graphic character set. 1) Locking shifts between G0 and G1 with SI in SO. Appendix A also mentions ESI and ESO, Extended Shift In and Out for locking shifts to the G2 and G3 sets, but no encoding is given neither there nor in X3.64. 2) Nonlocking shifts to G2 and G3 with SS2 and SS3. Encoded in X3.64 as 'N' and 'O' 3) Changeing characters sets with '(' F for G0 and and ')' F for G1. F is a byte between hex(40) and hex(7E). In appendix A, '*' F and '+' F is mentioned for selecting G2 and G3. They are not part of the standard. Question: Is there any standard for the meaning of F above. In the VT100, A = USASCII and B = Brittish. 4) Most interesting here is '$' F, that selects a multi byte character set to be used as the G0-set. All characters in the set must have the same number of bytes and must all be in the range hex(20) to hex(7E). A two byte set would give 9025 graphic characters per set. -- --------------------------------+--------------------------------------- Kjell Eiksson I Phone: + 46 8 7520000 Eriksson Information Systems AB I Telex: 15968 ericki S-163 98 Stockholm I UUCP: mcvax!enea!erix!erialfa!kjelle SWEDEN I