Omron V550-A20, Руководство по эксплуатации

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V550-A20 Operation Manual
Glossary
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Glossary of Terms
ACK - A control character sent to acknowledge that a transmis-
sion block has been received.
Address - A unique designation for the location of data or the
identity of a smart device; allows each device on a single
communications line to respond to its own message.
AEL (Accessible Emission Limit) - The average power limitations
of electronic radiation from a laser light source as defined by the
CDRH.
AIM - Automatic Identification Manufacturers, a trade association.
Alignment - The position of a scanner or light source in relation
to the target of a receiving element.
Alphanumeric - The character set which contains letters, digits
and other characters such as punctuation marks.
Ambient Light - The lighting conditions in the scanning area.
Ambient light can interfere with successful scanning of bar codes.
ANSI (American National Standards Institute) - The principle
standards development group in the U.S. A non-profit,
non-governmental group supported by over 1000 trade organiza-
tions, professional societies, and companies. Member body to the
ISO (International Standards Organization).
Aperture - Term used on the required CDRH warning labels to
describe the laser exit window.
ASCII (American Standard Code for Information Interchange) - A
seven bit plus parity code established by ANSI to achieve
compatibility between data services.
Aspect Ratio - The ratio of height to width of a bar code symbol.
A code twice as high as wide would have an aspect ratio of 2; a
code twice as wide as high would have an aspect ratio of ˚ or 0.5.
Asynchronous Transmission - Transmission in which the time
intervals between transmitted characters may be of unequal
length. Transmission is controlled by start and stop bits at the
beginning and end of each character.
Autodiscrimination - The ability of bar code reading equipment
to recognize and correctly decode more than one bar code
symbology.
Autodistinguish - The ability of a scanner to recognize a
selectable number of different symbologies and process the data
without operator intervention; this is a prerequisite feature of
linear bar code scanners employed in open systems.
Bar - The dark elements of a printed bar code symbol.
Bar Code - An array of rectangular bars and spaces that are
arranged in a predefined pattern to represent elements of data
referred to as characters.
Bar Code Character - A single group of bars and spaces that
represent an individual number, letter, or other symbol.
Bar Code Density - The number of characters that can be
represented in a linear unit of measure. Bar code density is often
referred to in characters per inch (CPI).
Bar Code Label - A label that carries a bar code and can be
affixed to an article.
Bar Code Reader - A device that examines a printed spacial
pattern and decodes the encoded data.
Bar Height - The height of the shortest bar in a bar code.
Bar Length - The bar dimension perpendicular to the bar width.
Bar Width - The thickness of a bar measured from the edge
closest to the symbol start character to the trailing edge of the
same bar.
Baud Rate - A unit used to measure communications speed or
data transfer rate; represents the number of discrete conditions or
events per second.
BCC (Block Check Character) - Used to check transmission
accuracy, a character transmitted by the sender after each
message block and compared with a block check character
computed by the receiver.
Bed Width - The width of the conveyor bed measured in inches.
BEL - A control character that is used when there is a need to call
for attention; it may control alarm or attention devices.
Belt Width - The width of the conveyor belt measured in inches.
Bidirectional - A bar code symbol capable of being read
successfully independent of scanning direction.
Bit (Binary Digit) -The contraction of binary digit, the smallest unit
of information in the binary system; a one or zero condition.
Bottom Read - When the scanner is mounted under the conveyor
to read codes on the bottom of the boxes or on the front or back
of the boxes. If used there is not enough clearance for a standard
front or back read.
BPS (Bits per Second) - Unit of data transmission rate. See baud
rate.
Buffer - A temporary storage device used to compensate for a
difference in data rate and data flow between two devices
(typically M).
Byte - A binary element string functioning as a unit, usually
shorter than a computer “word”. Eight-bit bytes are most common.
Also called a “character”.
CDRH - (National Center for Devices and Radiological Health)
This organization (a service of the Food and Drug Administration)
is responsible for the safety regulations governing acceptable
limitations on electronic radiation from laser devices. Omron is in
compliance with the CDRH regulations.
Character - A single group of bars and spaces in a code that
represent an individual number, letter, punctuation mark or other