Symbol LS4000P Series, Руководство по продукции

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Glossary-2
LS 4000P Series Product Reference Guide
Byte On an addressable boundary, eight adjacent binary digits (0 and 1) combined
in a pattern to represent a specific character or numeric value. Bits are
numbered from the right, 0 through 7, with bit 0 the low-order bit. One byte
in memory can be used to store one ASCII character.
CDRH Center for Devices and Radiological Health. A federal agency responsible for
regulating laser product safety. This agency specifies various laser operation
classes based on power output during operation.
CDRH Class 1 This is the lowest power CDRH laser classification. This class is considered
intrinsically safe, even if all laser output were directed into the eye's pupil.
There are no special operating procedures for this class.
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 encodation 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 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.
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.