Microscan MS-890, Руководство пользователя

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MS-890 Industrial Automation Scanner User Manual
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Appendices
Matchcode — The ability to compare symbols being scanned against a master symbol
that is stored in the memory of the scanner.
Embedded Menu — Configuration options embedded in the scanner’s erasable memory.
Mil — One thousandths of an inch or 0.0254 mm. In bar coding, a measurement standard
that measures a symbol by the width of its narrowest element.
Mismatch — An event that occurs when the scanned symbol does not match the master
symbol that is stored in the memory of the scanner.
Multisymbol — A scanner mode which allows a scanner to read more than one symbol in
a single read cycle.
Multidrop — A communications protocol for networking two or more scanners or other
devices with a concentrator (or controller) and characterized by the use of individual
device addresses and the RS-485 standard.
Narrow Bar Width — The width of the narrowest bar of a given symbol, expressed in
thousands of an inch (or mils).
Narrow Margins — Allows the scanner to read symbols with quiet zones less than 8
times the width of the narrow bar element.
Non-Delimited — A command that is not bracketed by pre-defined characters.
Non-Volatile RAM (NOVRAM) — Random Access Memory that is available on power on;
that is, after power to the unit has been recycled.
No Read — A failed decode attempt. A condition that occurs when the scanner is set up to
decode symbols but no symbol is scanned during the read cycle.
NOVRAM — Non-volatile random access memory. Data that is saved for “power on” is
saved to NOVRAM.
Number of Decodes — The number of times a symbol is scanned by the scanner during
one pass through the laser beam.
Object Detector — A photoelectric device used to sense the presence or absence of an
object (also referred to as a package detector).
Output — To transfer or transmit from the computer to a peripheral device or communications
line. A channel or communications line. Decoded data or discrete signal.
Output Format — The modification of data output according to a user-defined index of
Extraction and Insertion commands.
Parity — An error detection routine in which one data bit in each character is set to 1 or 0
so that the total number of 1 bits in the data field is even or odd.
Picket Fence Orientation — An orientation in which a symbol’s bars are perpendicular to
its direction of travel.
Pitch — Symbol (or scanner) rotation around the center of a line perpendicular to the
symbol’s bars.
Point-to-Point — A protocol consisting of a single communications event, typically used
to connect a scanner to a terminal or host computer.
Port — Logical circuit for data entry and exit. (One or more ports may be included within a
single connector.)