Symbol DS 6608, Руководство по продукции

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GL-3
CDRH Class 2 No additional software mechanisms are needed to conform to this limit. Laser
operation in this class poses no danger for unintentional direct human
exposure.
Character A pattern of bars and spaces which either directly represents data or indicates
a control function, such as a number, letter, punctuation mark, or
communications control contained in a message.
Character Set Those characters available for encoding in a particular bar code symbology.
Check Digit A digit used to verify a correct symbol decode. The scanner inserts the decoded
data into an arithmetic formula and checks that the resulting number matches
the encoded check digit. Check digits are required for UPC but are optional for
other symbologies. Using check digits decreases the chance of substitution
errors when a symbol is decoded.
Codabar A discrete self-checking code with a character set consisting of digits 0 to 9 and
six additional characters: ( - $ : / , +).
Code A set of unambiguous rules specifying the way in which data may be
represented as numbers and letters used to represent information (see number
system).
Code 128 A high density symbology which allows the controller to encode all 128 ASCII
characters without adding extra symbol elements.
Code 3 of 9 (Code 39) A versatile and widely used alphanumeric bar code symbology with a set of 43
character types, including all uppercase letters, numerals from 0 to 9, and 7
special characters (- . / + % $ and space). The code name is derived from the
fact that 3 of 9 elements representing a character are wide, while the
remaining 6 are narrow.
Code 93 An industrial symbology compatible with Code 39 but offering a full character
ASCII set and a higher coding density than Code 39.
Code Length Number of data characters in a bar code between the start and stop characters,
not including those characters.
Codeword As a symbol character value, this isan intermediate level of coding between
source data and the graphical encodation in the symbol.
Concatination The construction of a string of data from two or more strings by appending each
string in succession. The linking or chaining together of separate items of data
in a bar code symbol or of the data contained in two or more separate bar code
symbols (also referred to as message append and structured append).
Continuous Code A bar code or symbol in which all spaces within the symbol are parts of
characters. There are no intercharacter gaps in a continuous code. The absence
of gaps allows for greater information density.
Contrast The difference in reflectance between the black and white (or bar and space)
areas of a symbol.
Data Identifier A specified character or string of characters that defines the intended use of
the data element that follows. For the purposes of automatic data capture
technologies, data identifier refers to the alphanumeric identifiers as defined
in ANSI MH10.8.2, formerly known as ANSI/FACT data identifiers.