To enable a decoder to distinguish between the wide and narrow elements a minimum wide to narrow ratio is needed. Depending upon which resolution has been used for the printing of the bar code, the width of the wide element should be at least two times greater than the narrow element. A ratio of three to one is better. All elements of the same type should be printed the same size. (The width of a narrow bar should be the same as a narrow space.)
Extended Code 39 ? The full 128 character ASCII character set can be encoded by pairing Code 39 characters. Enabling Extended Code 39 causes the following characters to be output for each character pair.
Codabar ? A01234B
Codabar is a discrete, numeric code with special characters and four different start/stop characters. Each character is encoded as seven elements, with two or three of the elements wide. Allowable data characters are (0 - 9), special characters (- $ : / . + ), and start-stop characters ( A, B, C, D ). Each character has 7 elements ( 4 bars and 3 spaces).
Code 128 is a continuous, multilevel, full ASCII code. Each of the Code 128 characters consists of three bars and three spaces. The bars and spaces may be one, two, three, or four modules wide. The total length of each code 128 character is eleven modules, with the total length of the bar modules odd, and the total length of the space modules even.
The character set consists of 103 different characters, three different start characters, and one unique stop character. With the three different start characters, there are three different code subsets available. They are:
Code 11 ? A numeric, high density code with one special character - . Each character is encoded with five elements, either two wide and three narrow, or one wide and four narrow. The wide elements are a binary one (1), and the narrow elements are a binary zero (0).
Code 93 ? A continuous, multilevel full ASCII bar code which has characters constructed of three bars and three spaces. Each data character bar may be 1, 2, or 3 modules wide. The start/stop character has a 4 module wide bar. The all data character spaces may be 1, 2, 3, or 4 modules wide.
EAN Bar Code ? European Article Number. The international standard or system for applying unique article numbers and bar codes to products. The EAN bar code is a numeric only code, generally encoding 13 digits (known as EAN-13), though in specific circumstances shorter codes (EAN-8) and supplementary codes are used. The North American equivalent (now technically a subset of the EAN system) is the Universal Product Code (UPC).
EAN Bar Code Types ? The EAN Codes encode either 13 or 8 characters. The 13 character version is a superset of the UPC A code. The 8 character version is for printing on smaller packages.
V : Logistic Variant assigned by the manufacturer (trade items)
C : The last digit serves to check that those preceding have been correctly captured. It is always calculated using the previous digits.
EAN 13 ? 2 0 0 1 2 3 4 5 6 7 8 9 3
EAN 13 is used to encode thirteen characters. The first two characters are the flag characters that identify the country of origin, the next ten characters are the data characters, and the last character is the check character. NOTE: The UPC-A symbol is a subset of the EAN 13 symbols. A UPC-A symbol is an EAN 13 symbol with the first flag character set to zero.
EAN-13 for Retail Units ? the identification is a numeric code and has the following general structure:
|EAN Prefix||Company prefix & Item numbers||Check Digit|
|3 digits||9 digits||1 digit|
EAN-14 (former DUN-14): A trade unit containing identical products can be identified with either an EAN-13 or an EAN-14 number. The EAN-14 consist of the EAN number of the unit contained headed by a Logistic Variant of 1 digit which is different for each packaging level. The Logistic Variant is a number between 1 and 8. It is chosen by the manufacturer according to its specific needs.
|Logistic||EAN-13 number of the contained unit||Check|
|Variant||without the check digit||Digit|
|1 digit||12 digits||1 digit|
For further information access http://www.ean.be/html/Numbering.html#NUMBERS
Interleaved 2 of 5 (ITF). Especially adapted to the poor quality of packaging materials frequently used for trade items (corrugated cardboard), it is designed to be read by a fixed or portable bi-directional scanner. Interleaved 2 of 5 code is a numeric only bar code. Each character of this code is represented by five elements, two wide and three narrow. Wide elements are decoded as binary one (1), and narrow elements are decoded as binary zero (0). The wide to narrow element ratio should be between two and three. Whether or not the elements used to encode a character are bars or spaces depends upon the location of the character within the message. The first character of the message is encoded into the bars immediately following the start character. The second character of the message is encoded into the spaces between the bars of the first character, thus eliminating the inter-character space. Because of this, Interleaved 2 of 5 is a continuous bar code.
Due to the interleaving of the characters, the number of characters in an Interleaved 2 of 5 message must be even. The check character, if used, must be included in the character count. If the message has an odd number of characters, add a leading zero (0) to the message.
UCC/EAN-128 ? The UCC/EAN-128 Symbology uses Application Identifiers (AIs) to define the data architecture. AIs are prefixes which, followed by the relevant data, determine the contents of a wide range of information. AIs may be used for, amongst other things, item identification, measurements, quantities, traceability, dates, transaction references and location numbers. AIs and their data must be represented by the EAN-128 bar code symbology.
UCC/EAN-128 SYMBOLOGY ? The symbology specified for the representation of Application Identifier data is UCC/EAN-128, a variant of' Code 128', which use is exclusively reserved to EAN International and the Uniform Code Council (UCC). It is not intended to be used for data to be scanned at the point of sales in retail outlets. What are the benefits of the UCC/EAN-128 symbology? UCC/EAN-128 offers 3 major advantages, it is:
SSCC (Serial Shipping Container Code) ? with a secure bar code symbology, UCC/EAN-128. This combination allows all participants in the supply chain to use a common, standard solution for their individual tracking and tracing needs.
The UCC/EAN-128 bar code symbology requires AIs to define the data architecture. AIs are prefixes which indicate the meaning and format of the data which follows. They may be used for, amongst other things, item identification, measurements, quantities, traceability, dates, transaction references and location numbers. For more information access http://www.ean.be/html/SSCC.html#SSCC
UPC/EAN/JAN Codes ? The JAN codes are the same as the EAN codes, with the flag characters set to "49".
UPC Codes ? The Universal Product Code (UPC) specifications include three versions: A, D, and E. Version A, the regular version, is used to encode a twelve digit number. Version E, the zero suppressed version, is a six digit code used for marking small packages. Version D, the variable length version, is not commonly used for package marking. It is used in limited special applications. Both Version A and E may include either a 2 digit or a 5 digit supplemental encodation. These extra digits are primarily used on periodicals and books. Supplemental encodations are supported.
|UPC A||0 0 1 2 3 4 5 6 7 8 9 5|
Version A encodes a twelve digit number. The first number encoded is the number system character, the next ten digits are the data characters, and the last digit is the check character. The number system character is printed in human readable form to the left of the UPC symbol. Seven of the ten possible numbers have been assigned.
|UPC E||0 0 1 0 2 5 4|
Version E allows zeros to be removed from the data to be encoded, resulting in a shorter tag. The encodation of the data characters is different than Version A. Version E even parity characters are the same as Version A left hand characters. The odd parity characters are reversed right hand characters. For more information access http://www.hp.com/HP-COMP/barcode/barcode_index.asp