1、INTERNATIONAL STANDARD Information processing - Arabic 7-bit coded character set for information interchange Jeu de caracthres arabes cod code code extension . code table . control character . control function graphic character . graphic symbol . position . . . . . . . . . . . . . 1 . 1 1 . . 1 . 1
2、. 1 1 . . 2 . . 2 . . 2 5 Specification of the coded character set . . . . . . . . . . . . . . . 2 5.1 Control characters 2 5.2 Character SPACE . 4 5.3 Graphic characters. . 4 6 Composite graphic characters. 7 7 Vowel characters 7 8 Designation of the character set of this International Standard . .
3、 . . . . 7 9 Codetable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 10 Description of the control characters . . . . . . . . . . . . . . . . . . . . . 9 10.1 ACK ACKNOWLEDGE . 10.2 BEL BELL. 10.3 BS BACKSPACE . . . . 10.4 CAN CAN
4、CEL . 10.5 CR CARRIAGE RETURN 10.6 DC1 DEVICE CONTROL ONE 10.7 DC2 DEVICE CONTROL TWO 10.8 DC3 DEVICE CONTROL THREE 10.9 DC4 DEVICE CONTROL FOUR. 10.10 DEL DELETE 10.11 DLE DATA LINK ESCAPE. . . . . 9 9 9 9 9 9 9 9 9 9 9 iii IS0 9636: 1987 (E) 10.12 10.13 10.14 10.15 10.16 10.17 10.18 10.19 10.20 10
5、.21 10.22 10.23 10.24 10.25 10.26 10.27 10.28 10.29 10.30 10.31 10.32 10.33 EM ENDOFMEDIUM . ENQ ENQUIRY . EOT END OF TRANSMISSION . ESC ESCAPE . ETB END OF TRANSMISSION BLOCK ETX END OF TEXT. . FF FORMFEED . HT HORIZONTAL TABULATION . IS1 (US) INFORMATION SEPARATOR ONE (UNIT SEPARATOR). IS2 IRS) IN
6、FORMATION SEPARATOR TWO (RECORD SEPARATOR) IS3 (GS) INFORMATION SEPARATOR THREE (GROUP SEPARATOR) . IS4 (FS) INFORMATION SEPARATOR FOUR (FILE SEPARATOR). LF LINEFEED NACK NEGATIVE ACKNOWLEDGE . NUL NULL . SI SHIFT-IN SO SHIFT-OUT . SOH START OF HEADING. STX START OF TEXT . SUB SUBSTITUTE CHARACTER .
7、 SYN SYNCHRONOUS IDLE VT VERTICAL TABULATION . 9 9 9 9 9 9 9 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 11 Peculiarities relating to the conventional direction of Arabic writing . . . . . 10 INTERNATIONAL STANDARD IS0 9036 : 1967 (E) Information processing - Arabic 7-bit coded character set for in
8、formation interchange 1 Scope and field of application 1.1 This International Standard specifies a set of 120 characters (control characters and graphic characters such as letters, digits and symbols) with their coded representation. These characters are mandatory and unchangeable. 1.2 This characte
9、r set is primarily intended for the inter- change of information using the Arabic language among data processing systems and associated equipment, and within data communication systems. The need for graphic characters and control functions in data processing has also been taken into account in deter
10、mining this character set. 1.3 This character set includes control characters for code extension where its 120 characters are insufficient for particular applications. Procedures for the use of these control characters are specified in IS0 2022. 1.4 The definitions of some control characters in this
11、 Inter- national Standard assume that data associated with them are to be processed serially in a forward direction. When they are included in strings of data which are processed other than serially in a forward direction or when they are included in data formatted for fixed-record processing they m
12、ay have undesirable effects or may require additional special treatment to ensure that they result in their desired function. 2 Conformance and implementation 2.1 Conformance A coded character set is in conformance with this International Standard if it comprises the characters listed in clause 5 wi
13、th the specified coded representation. Equipment claimed to implement this International Standard shall be able to interchange information by means of this 7-bit coded character set. 2.2 Implementation The use of this character set requires definitions of its im- plementation in various media. For e
14、xample, these could in- clude punched tapes, punched cards, magnetic media and transmission channels, thus permitting interchange of data to take place either indirectly by means of an intermediate recor- ding in a physical medium, or by local connection of various units (such as input and output de
15、vices and computers) or by means of data transmission equipment. The implementation of this coded character set in physical media and for transmission, taking into account the need for er- ror checking, is the subject of other International Standards. 3 References IS0 646, Information processing - I
16、S0 7-bit coded character set for information interchange. IS0 2022, Information processing - IS0 7-bit and B-bit coded character sets - Code extension techniques. Arab Standard ASMO 449. International Register of Coded Character Sets to Be Used with Escape Sequences. 4 Definitions For the purpose of
17、 this International Standard the following definitions apply. 4.1 bit combination : An ordered set of bits that represents a character or is used as part of the representation of a character. 4.2 character: A member of a set of elements used for the organization, control or representation of data. 4
18、.3 coded character set; code: A set of unambiguous rules that establishes a character set and the one-to-one relationship between the characters of the set and their bit combinations. 4.4 code extension: The techniques for the encoding of characters that are not included in the character set of a gi
19、ven code. 4.6 code table: A table showing the character allocated to each bit combination in a code. 4.6 control character: A control function the coded representation of which consists of a single bit combination. 4.7 control function: An action that affects the recording, pro- cessing, transmissio
20、n or interpretation of data and that has a coded representation consisting of one or more bit combinations. 1 IS0 9038: 1987 (E) 4.8 graphic character: A character, other than a control function, that has a visual representation normally handwritten, printed or displayed. 4.9 graphic symbol: A visua
21、l representation of a graphic character or of a control function. 4.10 position: That part of a code table identified by its column and row co-ordinates. 5 Specification of the coded character set The bits of the bit combinations of the 7-bit code are identified by b7, bs, ba, b, bs, b2 and bf, wher
22、e b7 is the highest-order or most-significant bit and b, is the lowest-order, or least- significant bit. The bit combinations may be interpreted to represent integers in the range 0 to 127 in binary notation by attributing the follow- ing weights to the individual bits: Bit: b be b, b, “3 b “1 Weigh
23、t: 1 64 1 32 1 16 1 8 1 4 1 2 1 1 In this International Standard, the bit combinations are iden- tified by notation of the form x/y, where x is a number in the range 0 to 7 and y is a number in the range 0 to 15. The cor- respondence between the notations of the form x/y and the bit combinations con
24、sisting of the bits b7 to b, is as follows: - x is the number represented by b, bs and b5 where these bits are given the weights 4, 2 and 1 respectively; - y is the number represented by b, bs, b2 and b, where these bits are given the weights 8, 4, 2 and 1 respectively. The notations of the form x/y
25、 are the same as those used to identify code table positions, where x is the column number and y the row number (see clause 7). The 128 bit combinations of the 7-bit code represent control characters and graphic characters. The allocation of characters to bit combinations is based on the following p
26、rinciples: - the bit combinations O/O to l/l5 represent 32 control characters; - the bit combination 2/O represents the character SPACE, which is interpreted both as a control character and as a graphic character; - the bit combinations 2/l to 7/14 represent 86 graphic characters; eight of these bit
27、 combinations shall not be used; - the bit combination 7/15 represents the control character DELETE. The allocation of individual characters to the bit combinations of the 7-bit code is specified in clause 5. This International Standard assigns at least one name to each character. In addition, it sp
28、ecifies an acronym for each control character and for the character SPACE, and a graphic symbol for each graphic character. By convention, only capital letters, apostrophes and hyphens are used for writing the names of the characters. For acronyms only capital letters and digits are used. It is inte
29、nded that the acronyms and this convention be retained in all translations of the text. The names chosen to denote graphic characters are intended to reflect their customary meaning. However, this lnterntional Standard does not define and does not restrict the meanings of graphic characters. Neither
30、 does it specify a particular style or font design for the graphic symbols representing the characters when they are imaged. 5.1 Control characters The control characters of the 7-bit coded character set are classified in the following categories: a) Transmission control characters Transmission cont
31、rol characters are intended to control or facilitate transmission of information over telecommunica- tion networks. Procedures for the use of the transmission control characters on telecommunication networks are the subject of other International Standards. b) Format effecters Format effecters are m
32、ainly intended for the control of the layout and positioning of information on character-imaging devices such as printing and display devices. cl Code extension control characters Code extension control characters are used to extend the character set of the code. They may alter the meaning of one or
33、 more bit combinations that follow them in the data stream. Procedures for the use of the code extension con- trol characters are specified in IS0 2022. d) Device control characters Device control characters are intended for the control of local or remote devices or ancillary devices connected to a
34、data processing or data communication system. These con- trol characters are not intended to control data communica- tion systems; this should be achieved by the use of transmission control characters. e) Information separators Information separators are used to separate and qualify data logically.
35、There are four such characters. They may be used either in hierarchical order or non-hierarchically; in the latter case, their specific meanings depend on the application. f) Other control characters These are the control characters that fall outside the preceding categories. The composition of each
36、 category, and the allocation of the in- dividual control characters in each category to bit combinations of the 7-bit code are specified in 5.1.1 to 5.1.6; each of these sub- clauses contains a table consisting of three columns. The first column specifies the acronym of each control character, the
37、2 IS0 9036: 1987 (El second column specifies the standard name of the control character and the third column specifies the bit combination representing the control character concerned. Detailed functional descriptions of all control characters are given in clause 10. 5.1.1 Transmission control chara
38、cters The transmission control characters and their coded represen- tations are specified in table 1. Table 1 - Transmission control characters - Acronym Name SOH STX ETX EOT ENQ ACK DLE NAK SYN ETB START OF HEADING START OF TEXT END OF TEXT END OF TRANSMISSION ENQUIRY ACKNOWLEDGE DATA LINK ESCAPE N
39、EGATIVE ACKNOWLEDGE SYNCHRONOUS IDLE END OF TRANSMISSION BLOCK Coded representation Coded ,epresentation O/l Of2 o/3 o/4 O/5 O/6 l/O l/5 l/6 I/J 5.1.2 Format effecters The format effecters and their coded representations are specified in table 2. Table 2 - Format effecters - Coded representation Acr
40、onym Name Coded representation BS BACKSPACE O/8 HT HORIZONTAL TABULATION o/9 LF LINE FEED o/10 VT VERTICAL TABULATION o/11 FF FORM FEED o/12 CR CARRIAGE RETURN o/13 5.1.2.1 Concepts The definitions of the format effecters use the following con- cepts: a) A page is composed of a number of lines, each
41、 being composed of a number of character positions. b) Each character position is capable of imaging SPACE or a graphic symbol. c) The graphic symbol imaged at a character position represents a graphic character, a control function, or a com- bination of one or more graphic characters and/or control
42、 functions. d) The active position is the character position at which the action required by the next character in the data stream is to be effected. If the next character is a graphic character, its graphic symbol is imaged at that position; if it is a control character, the corresponding function
43、is performed relative to that position. e) Movements of the active position are effected as follows : 1) The active position is advanced one character posi- tion immediately after imaging a SPACE or a graphic symbol, and upon the execution of the function cor- responding to a control character for w
44、hich a graphic symbol is required to be imaged. 2) The active position is moved to a specified character position upon the execution of the function correspond- ing to a control character that is defined to cause a movement of the active position (i.e. a format effector). f) The active position is n
45、ot moved upon execution of the function corresponding to a control character that is neither required to be imaged by a graphic symbol nor defined to cause a movement of the active position. g) The effect of an attempt to move the active position beyond the boundaries of a line or a page is not defi
46、ned by this International Standard. 5.1.2.2 Combined horizontal and vertical movements of the active position The format effecters are defined for applications in which horizontal and vertical movements of the active position are ef- fected separately. If a single control character is required to ef
47、- fect the action of CARRIAGE RETURN in combination with a vertical movement, the format effector for that vertical move- ment shall be used. For example, if the function “new line” (equivalent to the combination of CARRIAGE RETURN and LINE FEED) is required as a single control character, bit com- b
48、ination O/IO shall be used to represent it. This substitution re- quires agreement between the sender and the recipient of the data, and the format effecters (LINE FEED, VERTICAL TABULATION and/or FORM FEED) that are affected shall be identified (see clause 10). In order to avoid the need for such p
49、rior agreement, to facilitate interchange and to avoid conflicts with specifications in other International Standards, the use of format effecters for vertical movement to effect combined horizontal and vertical movements is deprecated. It is strongly recommended to use two control characters, for example CARRIAGE RETURN (CR) and LINE FEED (LF) to obtain the effect of “new line”. 5.1.3 Code extension control characters The code extension control characters and their coded representations are specified in table 3. IS0 9836: 1987 (El Table 3 - Code extension control characters - Coded represe
