1、 g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58identification and data capture techniques Code 39 bar code symbology specificationICS 01.080.50; 3
2、5.040Information technology Automatic BRITISH STANDARDBS ISO/IEC 16388:2007BS ISO/IEC 16388:2007This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 July 2007 BSI 2007ISBN 978 0 580 56257 0Amendments issued since publicationAmd. No. Date Commen
3、tsThis publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.National forewordThis British Standard was published by BSI. It is the UK impl
4、ementation of ISO/IEC 16388:2007. It supersedes BS ISO/IEC 16388:1999 which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee IST/34, Automatic identification and data capture techniques.A list of organizations represented on this committee can be obtained on
5、request to its secretary.Reference numberISO/IEC 16388:2007(E)INTERNATIONAL STANDARD ISO/IEC16388Second edition2007-05-15Information technology Automatic identification and data capture techniques Code 39 bar code symbology specification Technologies de linformation Techniques didentification automa
6、tique et de capture des donnes Spcifications des symbologies des codes barres, code 39 BS ISO/IEC 16388:2007ii iiiContents Page Foreword iv Introduction v 1 Scope . 1 2 Normative references . 1 3 Terms and definitions. 1 4 Requirements 1 4.1 Symbology characteristics 1 4.2 Symbol structure 2 4.3 Cha
7、racter encodation. 2 4.4 Dimensions 4 4.5 Reference decode algorithm . 5 4.6 Symbol quality 6 4.7 Application-defined parameters 7 Annex A (informative) Additional features. 9 Annex B (informative) Guidelines for the use of Code 39 12 Annex C (normative) Symbology identifier . 15 Annex D (informativ
8、e) Example of application-defined parameters . 16 Bibliography . 18 BS ISO/IEC 16388:2007iv Foreword ISO (the International Organization for Standardization) and IEC (the International Electrotechnical Commission) form the specialized system for worldwide standardization. National bodies that are me
9、mbers of ISO or IEC participate in the development of International Standards through technical committees established by the respective organization to deal with particular fields of technical activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other international o
10、rganizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1. International Standards are drafted in accordance with the rules given in the ISO
11、/IEC Directives, Part 2. The main task of the joint technical committee is to prepare International Standards. Draft International Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as an International Standard requires approval by at least 7
12、5 % of the national bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights. ISO/IEC 16388 was prepared by Joint Technical Comm
13、ittee ISO/IEC JTC 1, Information technology, Subcommittee SC 31, Automatic identification and data capture techniques. This second edition cancels and replaces the first edition (ISO/IEC 16388:1999), which has been technically revised. BS ISO/IEC 16388:2007vIntroduction The technology of bar coding
14、is based on the recognition of patterns encoded in bars and spaces of defined dimensions. There are numerous methods of encoding information in bar code form, known as symbologies. Code 39 is one such symbology. The rules defining the translation of characters into bar and space patterns and other e
15、ssential features are known as the symbology specification. In the past, symbology specifications were developed and published by a number of organizations, resulting in certain instances in conflicting requirements for certain symbologies. Manufacturers of bar code equipment and users of bar code t
16、echnology require publicly available standard symbology specifications to which they can refer when developing equipment and application standards. BS ISO/IEC 16388:2007blank1Information technology Automatic identification and data capture techniques Code 39 bar code symbology specification 1 Scope
17、This International Standard specifies the requirements for the bar code symbology known as Code 39; it specifies Code 39 symbology characteristics, data character encodation, dimensions, tolerances, decoding algorithms and parameters to be defined by applications. It specifies the Symbology Identifi
18、er prefix strings for Code 39 symbols. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendmen
19、ts) applies. ISO/IEC 646, Information technology ISO 7-bit coded character set for information interchange ISO/IEC 15416, Information technology Automatic identification and data capture techniques Bar code print quality test specification Linear symbols ISO/IEC 15424, Information technology Automat
20、ic identification and data capture techniques Data Carrier Identifiers (including Symbology Identifiers) ISO/IEC 19762-1, Information technology Automatic identification and data capture (AIDC) techniques Harmonized vocabulary Part 1: General terms relating to AIDC ISO/IEC 19762-2, Information techn
21、ology Automatic identification and data capture (AIDC) techniques Harmonized vocabulary Part 2: Optically readable media (ORM) 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO/IEC 19762-1 and ISO/IEC 19762-2 apply. 4 Requirements 4.1 Symbology charact
22、eristics The characteristics of Code 39 are as follows. a) Encodable character set: 1) full alphanumeric A to Z and 0 to 9 (ASCII characters 65 to 90 and 48 to 57 inclusive, in accordance with ISO 646). BS ISO/IEC 16388:20072 2) special characters: space $ % + - . / (ASCII characters 32, 36, 37, 43,
23、 45, 46 and 47, respectively, in accordance with ISO 646). 3) start/stop character. b) Code type: discrete. c) Elements per symbol character: 9, of which 3 wide and 6 narrow, comprising 5 bars and 4 spaces. d) Character self-checking: yes. e) Data string length encodable: variable. f) Bidirectionall
24、y decodable: yes. g) Symbol check character: one, optional (see Annex A). h) Symbol character density: 13 to 16 modules per symbol character, inclusive of minimum intercharacter gap, depending on wide/narrow ratio. i) Non-data overhead: equivalent to 2 symbol characters. 4.2 Symbol structure As illu
25、strated in Figure 1, Code 39 symbols shall comprise a) leading quiet zone; b) start character; c) one or more symbol characters representing data (including symbol check character, if present); d) stop character; e) trailing quiet zone. A space, the intercharacter gap, shall separate characters with
26、in the symbol. QUIET ZONE START CHARACTER “1“ “A“ STOP CHARACTER QUIET ZONE1AFigure 1 Code 39 symbol 4.3 Character encodation 4.3.1 Symbol character structure Each symbol character comprises nine elements (five bars and four spaces) of which six are always narrow (either three narrow bars and three
27、narrow spaces, or five narrow bars and one narrow space) and three are always wide (one wide space and two wide bars when there are three narrow bars, or three wide spaces when there are five narrow bars). This parity feature enables character self-checking to be carried out. BS ISO/IEC 16388:200734
28、.3.2 Symbol character assignments Table 1 defines all the Code 39 character assignments. Table 1 Code 39 character assignments Char. Encodation Patern BSBSBSBS B ASCII value 0 00011010 0 48 1 10010000 1 49 2 00110000 1 50 3 10110000 0 51 4 00011000 1 52 5 10011000 0 53 6 00111000 0 54 7 00010010 1 5
29、5 8 10010010 0 56 9 00110010 0 57 A 10000100 1 65 B 00100100 1 66 C 10100100 0 67 D 00001100 1 68 E 10001100 0 69 F 00101100 0 70 G 00000110 1 71 H 10000110 0 72 I 00100110 0 73 J 00001110 0 74 K 10000001 1 75 L 00100001 1 76 M 10100001 0 77 N 00001001 1 78 O 10001001 0 79 P 00101001 0 80 Q 00000011
30、 1 81 R 10000011 0 82 S 00100011 0 83 BS ISO/IEC 16388:20074 Char. Encodation Patern BSBSBSBSBASCII value T 000010110 84 U 110000001 85 V 011000001 86 W 111000000 87 X 010010001 88 Y 110010000 89 Z 011010000 90 hyphen 010000101 45 period 110000100 46 space 011000100 32 $ 010101000 36 / 010100010 47
31、+ 010001010 43 % 000101010 37 S/S or * 010010100 none NOTE 1 S/S denotes the start and stop character, usually graphically represented as * NOTE 2 In the columns headed B and S, 0 represents a narrow element and 1 a wide element. 4.3.3 Start and stop characters The Code 39 start and stop character i
32、s usually depicted in human-readable form by a * (asterisk). This character shall not form part of the data encoded elsewhere in the symbol and shall not be transmitted by the decoder. The start character shall be positioned at the normal left end of the data symbol characters, separated from the fi
33、rst bar of the leading data character by an intercharacter gap. The stop character shall be positioned at the normal right end of the data symbol characters (including symbol check character if present), separated from the final bar of the trailing data character by an intercharacter gap. 4.3.4 Opti
34、onal symbol check character Annex A defines the symbol check character position and calculation. 4.4 Dimensions Code 39 symbology shall use the following nominal dimensions. a) Width of narrow element (X): the X dimension of Code 39 symbols should be defined by the application specification having d
35、ue regard to the availability of equipment for the production and reading of symbols and complying with the general requirements of the application. See 4.7.1. b) Wide/narrow ratio (N): 2,0 : 1 to 3,0 : 1. BS ISO/IEC 16388:20075c) Width of intercharacter gap (I): 1) minimum: equal to X; 2) maximum:
36、for X 3,4: Grade 0. 4.6.2.2 Intercharacter gap For symbols with a measured narrow element width (Z) less than 0,287 mm, the maximum allowed intercharacter gap is 5,3Z. For symbols with Z greater than or equal to 0,287 mm, the maximum intercharacter gap is the greater of 3Z or 1,52 mm. Each interchar
37、acter gap in the scan reflectance profile under ISO/IEC 15416 shall be measured and graded as follows. I Gmax: Grade 4. I %I %N %S US %E ? %J _ %O DEL %T or %X or %Y or %Z BS ISO/IEC 16388:200712 Annex B (informative) Guidelines for the use of Code 39 B.1 Autodiscrimination compatibility Code 39 may
38、 be read by suitably programmed bar code decoders which have been designed to autodiscriminate it from other symbologies. The decoders valid set of symbologies should be limited to those needed by a given application to maximize reading security. When Code 39 is used in an autodiscrimination environ
39、ment with Interleaved 2 of 5 symbols, the following guidelines shall be followed: a) The nominal intercharacter gaps in the Code 39 symbols shall be no wider than the narrow elements. b) The reading system shall be constrained and the decoder programmed to ensure that the number of characters (inclu
40、ding start and stop characters) in all Code 39 symbols is greater than one-half of the number of data characters in the Interleaved 2 of 5 symbols. c) Interleaved 2 of 5 symbols shall have a minimum length of six characters in environments where they are autodiscriminated with Code 39. The use of fi
41、xed length symbols, bearer bars and check characters with the Interleaved 2 of 5 symbols as recommended in ISO/IEC 16390 provides additional protection in an autodiscrimination environment. B.2 System considerations It is important that the various components (printers, labels, scanners) making up a
42、 bar code installation operate together as a system. A failure in any component, or a mismatch between them, can compromise the performance of the overall system. The characteristics of the printer, symbol and scanner should be matched to achieve the desired performance. B.3 Printing considerations
43、B.3.1 Pixel-based printing Graphics software used to create bar codes on pixel-based printers must scale each bar and space exactly to the pixel pitch of the printer being used, irrespective of the symbology. For two-width symbologies like Code 39 the number of pixels comprising narrow bar and space
44、 elements, before any compensation for bar width growth or loss, shall be a fixed and constant integer, and the number of pixels comprising wide elements, before any compensation for bar width growth or loss, shall be the integer product of the number of pixels in the narrow element multiplied by th
45、e wide:narrow ratio. The width of any required inter-character gap shall also be a fixed integer number of pixels. Therefore, a given printer can only print a certain set of X dimensions and wide:narrow ratios. Compensation for uniform bar width growth (or loss) must be in equal offsetting amounts o
46、n all bars and spaces in the symbol. This may be accomplished by changing an integer number of pixels from dark to light or light to dark in the same manner for each bar-space pair in the symbol and for the last bar in the symbol. For BS ISO/IEC 16388:200713example, all pixels along the same edge of
47、 every bar in the symbol could be changed from dark to light, or pixels along both edges of every bar in the symbol could be changed from dark to light, provided that the printer resolution is sufficient to allow this to be performed satisfactorily. Any set of dark to light or light to dark pixel ch
48、anges is acceptable provided the adjustment is performed consistently across the whole symbol and does not change the total symbol character width. Failure to follow these principles results in degraded symbol quality and often results in unreadable symbols. General purpose printing software designed to support a wide range of printers should provide the user with the capability of adjusting the X dimension and bar width growth or loss. Programmers Example These principles can be reduced to the following rules for digital bar code design
