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Protocol
A formal set of conventions governing the formatting and relative timing of message
exchange between two communicating systems.
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.
Skew
Rotation about the Y-axis. Rotational deviation from correct horizontal and vertical
orientation; may apply to single character, line or entire encoded item. See pars. 2.5.
Symbol
A combination of characters including start/stop and checksum characters, as required, that
form a complete scannable barcode.
Tilt
Rotation around the Z axis. Used to describe the position of the barcode with respect to the
laser scan line. See pars. 2.5.
Trigger Signal
A signal, typically provided by a photoelectric sensor or proximity switch, which informs the
scanner of the presence of an object within its reading zone.
UPC
Acronym for Universal Product Code. The standard barcode type for retail food packaging in
the United States.
Visible Laser Diode
A light source used in scanners to illuminate the barcode symbol. Generates visible red light
at wavelengths between 630 and 680 nm.
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