Microscan MS-890, Руководство пользователя

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MS-890 Industrial Automation Scanner User Manual
Glossary of Terms
Protocol — The rules for communication between devices, providing a means to control
the orderly flow of information between linked devices.
Quiet Zone — Specified “clear” (nonprinted) area immediately before and after the symbol.
The area is usually white (for black and white symbols) and at least 10 times the width of
the narrowest bar, as measured in thousands of an inch. The quiet zone can be a shade or
color other than white as long as its density remains consistent and it has the required
contrast relative to the bars.
RAM (Random Access Memory) — Memory that is lost after power is recycled to the unit.
Raster — Multiple stacked scans produced by a separate oscillating mirror or by a spinning
mirror with varying facet angles.
Read Cycle — A programmed period of time or condition during which the scanner will
accept symbol input.
Read Range — The distance within which a symbol can be read reliably, as measured
from the front of the scanner.
Relay — An electrical switch that allows a low power to control a higher one.
Reset — Clears current data and initializes counters and configuration parameters.
ROM (Read-Only Memory) — Memory that cannot be changed.
Scanner — A scanning device that is comprised of a scan head and a decoder integrated
in one package.
Scan Rate (SR) — The number of decodes per second that a given scanner is capable of
casting.
Scan Width (SW) — The width across the scan beam at a given distance from the scanner
in which a symbol can be read.
Separator — A character that separates data fields.
Serial Commands — Online data strings such as <D> or <P> sent from a host or auxiliary
terminal to a scanner or other device.
Serial Configuration (Host Configuration) — Serial command specifically for changing
configuration and distinguished from operational command by the fact that they modify the
non-volatile for power up configuration.
Skew — Symbol (or scanner) rotation around the center of the skew axis.
Specular Reflection Zone — The narrow zone straight out from the scanner in which
direct reflected light from a symbol can distort the scanner’s ability to distinguish bars from
spaces.
Supplemental — A character or data string that is appended to the main symbol.
Sweep — One pass of the raster, up or down.
Sweep Rate (SwR) — The number of passes per second, up or down, describing the raster
image.
Symbol Density — The number of characters per inch (or other unit of measure) encoded
in a symbol.
Symbol Height — Regardless of orientation, the measurement taken along the length of
a symbol’s individual bars.