Intermec EasyCoder 4100, Руководство пользователя

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Fr Goth
Designing Labels and Using Commands
Helvitica condensed 9 pt italic
Co d e 39 18 p t
Code 128
Code 128 was introduced in 1981 as a very high density, alphanumeric
symbology. It is variable length, continuous code that employs multiple
element widths. Each Code 128 character has 11 modules which may be either
black or white. Each character has three bars and three spaces. Code 128 has
106 different printed characters. Each printed character can have one of three
different meanings, depending on which of three different character sets is used.
Three different start characters tell the equipment which of the character sets is
being used, and three shift codes permit changing characters sets inside a
symbol. Code 128 has been adopted by the Uniform Code Council (UCC) for
marking shipping containers.
UPC
Universal Product Code (UPC) is a fixed-length, numeric, continuous weakly
self-checking symbology that has been used in the supermarket industry since
1973. It is a subset of EAN. UPC is a coding system as well as a symbology; it is
designed to identify a product and its manufacturer. UPC uses four element
widths. Two common types of UPC are Version A, which encodes 12 digits and
Version E which encodes 6 digits. The first digit of a UPC Version A represents
the number system. It indicates what type of product the symbol is identifying.
The next five digits comprise a code identifying the product‘s manufacturer, and
the next five digits represent the product code. The final digit is a check digit.
EAN
The European Article Numbering system (abbreviated as EAN) is a numeric
superset of UPC. EAN has both a version that uses 8 digits and a version that
uses 13 digits. The version with 13 digits encodes the same number of bars as 12
digit UPC Version A, but the thirteenth digit is encoded into a parity pattern of
the left-hand six digits. This thirteenth digit, in combination with the twelfth
digit, defines two flag characters that represent a country code. An EAN-8
symbol as a left-hand guard pattern, four odd parity digits, a center guard
pattern, four even parity digits, and a right-hand guard pattern. An EAN-8
symbol encodes two flag digits, five data digits, and one check digit.
POSTNET
The Postal Numeric Encoding Technique (POSTNET) was developed by the
U.S. Postal Service to provide bar codes with ZIP Code information for
envelopes. The code is easily read by optical reading systems, and because the
information is presented several times within the bar code, it is easy to find and
fix errors.