84
Software and other controls to limit exposure to laser light may be
required to achieve CDRH Class 1 operation. The CDRH time base
for Class 1 devices is 10,000 seconds.
CDRH Class 2
CDRH Class 2 devices may not emit more than 1 milliwatt average
radiant power. For this scan engine, additional software controls are
not necessary. Eye protection for CDRH Class 2 devices is normally
afforded by aversion responses, including the blink refl ex.
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.
CLSI Editing
An option which inserts a space after the 1st, 5th, and 10th
characters
of a 14-character Codabar symbol. Length includes start and stop
characters.
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.
Summary of Contents for Speechmike 6294
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