ITU-T T 562-1988 TERMINAL CHARACTERISTICS FOR TELETEX PROCESSABLE MODE PM 1《智能用户电报可处理方式PM 1的终端特性》.pdf

1、INTERNATIONAL TELECOMMUNICATION UNION)45G134 4 TELECOMMUNICATIONSTANDARDIZATION SECTOROF ITU4%2-).!,G0G0%15)0-%.4G0G0!.$G0G002/4/#/,3G0G0(b) that these applications, in some cases, can be conveniently combined into one single terminal to giveimproved performance to the users of these terminals;(c) t

2、hat standardization work has been aiming at common protocols and compatible parameters for variousequipments and procedures;unanimously declaresthat processable mode characteristics should be designed and operated in accordance with the followingstandards.1 Scope1.1 The international teletex service

3、 requirements to the processable mode of operation PM.1 are defined inRecommendation F.220.1.2 This Recommendation defines terminal characteristics unique to the processable mode of operation PM. 1.2 Field of applicationThis Recommendation applies to terminal equipment of the teletex service support

4、ing the processable mode ofoperation PM.1.3 ReferencesThe following CCITT Recommendations also apply to equipments for processable mode of operation:2 Fascicle VII.7 - Rec. T.562 Rec. T.60: “Terminal equipment for use in teletex service“; Rec. T.61: “Character repertoire and coded character sets for

5、 the international teletex service“; Rec. T.62: “Control procedures for the teletex and Group 4 facsimile services“; Rec. T.70: “Network-independent basic transport service for telematic services“; Rec. T.400 Series: “Document architecture, transfer and manipulation“; Rec. T.502: “A document applica

6、tion profile PM.1 for the interchange of processable formdocuments“; Rec. T.522: “Communication application profile BT1 for document bulk transfer“.4 DefinitionsTerms and their definitions are defined by Recommendations listed above.5 General characteristics of the equipment5. 1 General5.1.1 Equipme

7、nts supporting processable mode of operation PM.1 shall provide a set of basic features. The ability toprovide this minimum set of basic features is indicated and negotiated before the document interchange.5.1.2 These equipments may in addition to the set of basic features provide other facilities.

8、These facilities arenegotiated separately from the set of basic features defined below.5.1.3 Some basic and/or non-basic features are allowed to be approximated by the receiver using fall-backtechniques. These features are defined in 6.1.3.5.1.4 The negotiation is only allowed to fail when a non-bas

9、ic feature is required that is not supported by therecipient and for which no suitable fall-back mode is available.5.2 Basic features required for equipments supporting processable PM.1The basic features required for equipments supporting processable mode of operation are:5.2.1 The ability to create

10、, transmit and receive document conforming to the document application profile PM.1defined in Recommendation T.502;5.2.2 The ability to interchange documents by using the application context defined in 7.1 of this Recommendation;5.2.3 The ability to handle the basic nominal page defined in 6.1.1.3 a

11、nd to provide, at least, the assuredreproduction area which is defined for the basic nominal page in 6.1.1.4;5.2.4 For character content, the ability to handle the basic features defined in Recommendation T.502;5.2.5 The ability to handle the call identification line information (see 6.1.2);5.2.6 A

12、teletex equipment supporting PM.1 shall be able to convert PM.1 documents in formatted and/or formattedprocessable forms into basic teletex documents.5.3 Non-basic features for processable modeOne or mode additional features listed in this section may be provided by a terminal supporting PM.1.5.3.1

13、The ability to handle the nominal page and to provide, at least, the assured reproduction area which are definedfor North American letter paper size, ISO A3 paper size (see 6.1.1.3 and 6.1.1.4).Fascicle VII.7 - Rec. T.562 35.3.2 The ability to negotiate additional presentation characteristics for ch

14、aracters. These non-basic characteristics arespecified in Recommendation T.502.6 Document handling6.1 Requirements for the imaging process6.1.1 Dimensions for text presentation6.1.1.1 Basic measurement unit (BMU)The size of the basic measurement unit (BMU) is 1/1200 25.4 mm if the output medium is p

15、aper and thelocally defined scaling factor is one.6.1.1.2 Paper sizeDifferent physical paper sizes can be used for presentation of PM.1 formatted form document. Such paper sizesare ISO A4 paper size (210 297 mm), North American letter paper size (215.9 279.4 mm), ISO A3 paper size (297 420 mm).Chara

16、cter content may be imaged on those sheets of paper in horizontal as well as in vertical orientation. Asingle orientation must be used for all characters within one side of the sheet of paper (recto or verso).6.1.1.3 Pages and nominal pagesAs defined in Recommendation T.412, a page is a rectangular

17、area used as the reference area for positioningand imaging the content of the document. The page is intended to be positioned and imaged on a unit of thepresentation surface. The ideal size of the presentation surface, as assumed by the sender of a document is the nominalpage.The basic page dimensio

18、ns are: width 9 240 BMU (195.6 mm); height 12 400 BMU (262.5 mm).Others than the basic page dimensions are optional. These dimensions are given below:a) page dimensions for the ISO A4 paper size: width 9 920 BMU (210 mm); height 14 030 BMU (297 mm);b) page dimensions for the North American letter pa

19、per size: width 10 200 BMU (215.9 mm); height 13 200 BMU (279.4 mm);c) page dimensions for the ISO A3 paper size: width 14 030 BMU (297 mm); height 19 840 BMU (420 mm).6.1.1.4 Assured reproduction areaHard-copy devices must allow for the possibility of edge losses caused, for example by the optional

20、 printing ofa call identification line at the receiver, by tolerances on the physical paper size, and by equipment tolerance (seeAnnex A of Recommendation T.60). In order to cater for these edge losses, an assured reproduction area is definedwhich is the rectangular area that remains on the nominal

21、page after deducting an agreed allowance for edge losses.4 Fascicle VII.7 - Rec. T.562For the option of printing a call identification line, an area at the top of the page is reserved. The same area isused for both vertical and horizontal image orientations. If used, the call identification line is

22、to be printed on thesecond character baseline which is 400 BMU (8.466 mm) from the X-axis. The reserved area consists of 72 characterboxes, each 120 BMU in width and 200 BMU in height, starting at 945 BMU (20 mm) from the Y-axis and extendingfor 8 640 BMU. The maximum permitted character baseline of

23、fset of these character boxes is 72 BMU, so that the areaof assured reproduction starts at 472 BMU (10 mm) from the X-axis. Any interchanged text in the area of thesecharacter boxes may be suppressed, to avoid obscuring the image of the call identification line.The assured reproduction areas are def

24、ined as follows:a) ISO A4 assured reproduction area: width = 9 240 BMU; height = 13 200 BMU; top margin = 472 BMU; left margin = 345 BMU;b) North American letter assured reproduction area: width = 9 240 BMU; height = 12 400 BMU; top margin = 472 BMU; left margin = 345 BMU;c) ISO A3 assured reproduct

25、ion area: width = 13 200 BMU; height = 18 480 BMU; top margin = 472 BMU; left margin = 345 BMU.The assured reproduction areas for ISO A4, North American letter, and ISO A3 are illustrated inFigure 1/T.562, Figure 2/T.562, Figure 3/T.562, respectively, showing the maximum edge losses on each paper ed

26、ge.The indicated edge losses are based on the idealized or nominal paper sizes as defined in 6.1.1.2 and do not takeaccount of paper size tolerances.Fascicle VII.7 - Rec. T.562 5 6 Fascicle VII.7 - Rec. T.5626.1.1.5 Positioning of the page relative to the nominal pageThe rules defined in Recommendat

27、ion T.412, 7.3.2 apply.6.1.1.6 Positioning of pages on soft copy mediaThe rules defined in Recommendation T.412, 7.3.5 apply.6.1.2 Call identification line (CIL)6.1.2.1 The basic CIL presentation rules as defined in Recommendation F.200 should apply with the restrictionspecified in Recommendation F.

28、220 (deletion of the page number from the CIL).6.1.2.2 For printing the CIL, an area as defined in 6.1.1.4 is provided.6.1.3 Fall-back techniquesSome basic and non-basic features described in Recommendation T.502 are allowed to be approximated usingfall-back techniques.This paragraph determines the

29、fall-back procedure which may be used by the recipient if features present in theinterchanged document are not locally available.Table 1/T.562 below identifies the features for which fall-back procedure may be used. All other features, notlisted in this table, must not be approximated.Fascicle VII.7

30、 - Rec. T.562 7TABLE 1/T.562Features Fall-back modesDocument layout featuresSeparationWidows and orphansAssociation of paragraphsRecto/verso pagesIGNOREIGNOREIGNORERECTOContent layout and imaging featuresEmphasis italicized boldBold or underlinedItalicized or underlinedDocument management features I

31、GNORE6.2 Requirements for the formatting processThe formatting process shall be capable to format locally a processable PM.1 document into the formatted orthe formatted-processable form before the document is sent. Additional requirements are for further study.6.3 Requirements for the editing proces

32、sFor further study.6.4 Requirements for the imaging processThe rules for printing or displaying on screen described in Recommendation T.60 only apply to PM. 1documents in formatted and/or formatted-processable forms. Additional requirements are for further study.7 Communication aspects7.1 Applicatio

33、n context for interchange of PM.1 documentsThe application context to be used for the interchange of PM.1 documents is defined inRecommendation T.561, 7.17.2 Coding schemes available7.2.1 Recommendation T.61 defines the coding scheme to be used for character content.7.3 Receiving capabilities7.3.1 The negotiation of the storage capacity by the DTAM protocol is mandatory for equipments providingprocessable mode of operation.8 Interworking between basic teletex equipments and teletex equipments supporting PM.1The rules defined in Recommendation T.561, 8 apply.