1、INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Amendment 1 TERMINALS FOR TELEMATIC SERVICES T.51 (08/95) LATIN BASED CODED CHARACTER SETS FOR TELEMATIC SERVICES Amendment I to ITU-T Recommendation T.51 (Previously “CCITT Recommendation”) STD-ITU-T RECMN T
2、51 AND 1-ENGL 2995 +Ab2591 Ub3b37L 598 D FOREWORD The IT-T (Telecommunication Standardization Sector) is a permanent organ of the International Telecommunication Union (ITU). The ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommen- dations on them with a
3、 view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Conference (WTSC), which meets every four years, establishes the topics for study by the IT-T Study Groups which, in their turn, produce Recommendations on these topics. The approval of Recomm
4、endations by the Members of the IT-T is covered by the procedure laid down in WTSC Resolution No. 1 (Helsinki, March 1-12, 1993). Amendment 1 to IT-T Recommendation T.5 1, was prepared by IT-T Study Group 8 (1 993-1996) and was approved under the WTSC Resolution No. 1 procedure on the 1 lth of Augus
5、t 1995. NOTE In this Recommendation, the expression “Administration” is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. O ITU 1996 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, e
6、lectronic or mechanical, including photocopying and microfilm, without permission in writing from the ITU. - - STD.ITU-T RECMN T-51 AND 1-ENGL 1995 m Lib259L Ob3b372 424 - CONTENTS Page 1 Annex D - T5 1 String D.1 Scope . 1 D.2 Graphic character sets . 1 D.3 Code extension techniques 1 D.4 Repertoir
7、e of the Latin based character set . 1 D.5 Control functions 1 Annex E . 4 References 4 Editorial changes to CCITT Recommendation T.5 1 (09/92) . 4 Recommendation T.51/ Amd.1 (08/95) STD-ITU-T RECMN T-51 AMD 1-ENGL 1775 48b2571 Ob3b373 3b0 SUMMARY Amendment 1 contains two new annexes, i.e. “Annex D7
8、 T5 1 String” and “Annex E, References”. 11 Recommendation T.51 / Amd.1 (08/95) STD-ITU-T RECMN T.51 AND 1-ENGL 1995 = 48b2591 b36374 2T7 Amendment 1 to Recommendation T.51 LATIN BASED CODED CHARACTER SETS FOR TELEMATIC SERVICES (1995) Annex D TSlString D.l Scope This annex describes the rules to be
9、 applied when Recommendation T.51 is referenced by other telematic recommendations for the simplified use of Recommendation T.51, e.g. the encoding of names, strings. The TSlString defined by this annex serves as a reference model by restricting Recommendation T.51 to those elements of the code exte
10、nsion mechanisms, of the character sets and repertoire which are necessary to define such simplified character strings coded according to Recommendation T.5 1. In the view of these restrictions, this annex is not specific to a defmed telematic service. D.2 Graphic character sets The primary set of g
11、raphic characters (see Figure D.1) is identical with the set of graphic characters of International Reference Version (IRV) of the 7-bit coded character set of Recommendation T.50. The supplementary set of graphic characters is specified in Figure D.2. For the TSlString the following applies: - - Th
12、e primary set is designated as the Go set and invoked in columns 2 to 7 of the code table. The supplementary set is designated as a G2 set. In the 8-bit environment the set is invoked in columns 10 to 15. In the TSlString no designation and invocation sequences are allowed. All characters in column
13、4 of the supplementary set are non-spacing characters (diacritical marks). Unallocated code positions are reserved and shall not be used. The compatibility provisions described in 2.2.4, Notes 3,4 and 6 are not applied. - - - - D.3 Code extension techniques In the &bit environment no code extension
14、sequence is allowed. In the 7-bit environment the single shift function SS2 (code 1/9) is used to invoke one character from the G2 set. All other shift functions are not allowed. D.4 The T51String repertoire is identical with the superset of the repertoire of the Latin based character set specified
15、in Annex A/TS 1. All combinations of diacritical marks with basic letters as specified in Figure A.2 are supported. The notes and remarks from A.4/T.5 1 shall not apply. Repertoire of the Latin based character set D.5 Control functions invocation and designation sequences for control functions are n
16、ot allowed. From columns O and 1 of the code table in use only the control characters CR - Carriage Return (0/13) and LF - Line Feed (0/10) can be used. They are specified in Recommendation T.50. Recommendation T.51/ Amd.1 (08195) 1 2 110012 110113 111014 111115 FIGURE D. UT.5 1 Primary set of graph
17、ic characters for T51String Recommendation T.51 / Amd.1 (08195) STD-ITU-T RECMN Te51 AMD L-ENGL 1775 48b259L Ob3b37b 07T , “ 110012 l4 D D 34 58 Y ri 101111 110113 2 “ 38 T t I11014 111115 8 “ SHY 7 T082443C-%/d2 FIGURE D.2T.51 Supplementary set of graphic characters for T51String Recommendation T.5
18、1 / Amd.1 (08/95) 3 STD-ITU-T RECNN Ta51 AND It-ENGL I995 4b2591 Ob3b377 Tob Annex E References - CCITT Recommendation T.50 (1 992), International Reference Alphabet (IRA) formerly International Alphabet No. 5 or IA5) Information technology - 7-bit coded character set for information interchange. IT
19、U-T Recommendation T.52 (1 993), Non-Latin coded character sets for telematic services. ITU-T Recommendation T.53 (1 994), Character coded control functions for telematic services. ITU-T Recommendation T.60 (1993), Terminal equipment for use in the teletex service. CCITT Recommendation T.6 1 (1988),
20、 Character repertoire and code character sets for the international teletex service. (To be deleted) ITU-T Recommendation T.lO1 (1994), International intenuorkingfor videotex services. CCITT Recommendation X.208 (1988), Specification of Abstract Syntax Notation One (ASN. I). ISO/IEC 2022: 1994, Char
21、acter code structure and extension techniques. ISO/IEC 6937: 1994, Information technology - Coded graphic character set for text communication - Latin alphabet. - ISO, International register of coded character sets to be used with escape sequences. Editorial changes to CCITT Recommendation T.51 (091
22、92) In 1.1 (d) of T.51 (09/92) instead of: “T.61” put “T.60/T.61”. In 1.2 of T.51 (09192) delete the text after the last comma: “, i.e. in Recommendations T.61 and T.101”. In 2.2.4, Note 3 and Note 4 of T.51 (09/92) replace: CCITT by “ITU-T”. Add a new 3.2.18: “3.2.18 Repertoire A specified set of c
23、haracters that are represented by the combination of a coded character set.” Add new paragraph 1.10 with the following text: The TSlSring is defined in Annex D. In Figure 1F.51 in position 2/0 should appear: SP. In Figure 2R.51 in position 6/14 the character representation should be corrected to: N.
24、 In Annex A, paragraph A.l the second sentence should read as follows: Each graphic character is identified by the identification system (see A.2). In Table A.lF.51 first column third row should read: Acute accent. In Figure A.lm.51 the last row should be removed: G = Greek alphabetic character. In A.4.2.3 second column second row should be: Space. NOTE - Some of the identifiers need to be revised (in collaboration with ISOAEC JTC lSC2NG3). Recommendation T.51 / Amd.1 (08195)
