Picket-Fence Orientation
When the barcode’s bars are positioned vertically on the product, causing them to
appear as a picket fence. The first bar will enter the scan window first. See par. 3.2.2.
Pitch
Rotation of a code pattern about the X-axis. The normal distance between center line
or adjacent characters. See pars. 2.2 and 2.5.
Position
The position of a scanner or light source in relation to the target of a receiving
element.
Protocol
A formal set of conventions governing the formatting and relative timing of message
exchange between two communicating systems.
Raster
The process of projecting the laser beam at varied angles spaced evenly from each
other. Typically, the mirrored rotor surfaces are angled to create multiple scan lines
instead of a single beam.
Resolution
The narrowest element dimension which can be distinguished by a particular reading
device or printed with a particular device or method.
RS232
Interface between data terminal equipment and data communication equipment
employing serial binary data interchange.
RS485
Interface that specifies the electrical characteristics of generators and receivers for
use in balanced digital multipoint systems such as on a Multidrop line.
Scanner
A device that examines a printed pattern (barcode) and either passes the
uninterpreted data to a decoder or decodes the data and passes it onto the Host
system.
Serial Port
An I/O port used to connect a scanner to your computer, identifiable by a 9-pin or 25-
pin connector.
Signal
An impulse or fluctuating electrical quantity (i.e.: a voltage or current) the variations of
which represent changes in information.
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