Motorola MC75A, User Manual

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Glossary - 7
R
RAM. Random Access Memory. Data in RAM can be accessed in random order, and quickly written and read.
Reflectance. Amount of light returned from an illuminated surface.
Resolution. The narrowest element dimension which is distinguished by a particular reading device or printed with a
particular device or method.
RF. Radio Frequency.
ROM. Read-Only Memory. Data stored in ROM cannot be changed or removed.
Router. A device that connects networks and supports the required protocols for packet filtering. Routers are typically used
to extend the range of cabling and to organize the topology of a network into subnets. See Subnet .
RS-232. An Electronic Industries Association (EIA) standard that defines the connector, connector pins, and signals used to
transfer data serially from one device to another.
S
Scanner. An electronic device used to scan bar code symbols and produce a digitized pattern that corresponds to the bars
and spaces of the symbol. Its three main components are: 1) Light source (laser or photoelectric cell) - illuminates a bar
code,; 2) Photodetector - registers the difference in reflected light (more light reflected from spaces); 3) Signal
conditioning circuit - transforms optical detector output into a digitized bar pattern.
Scanning Mode. The scanner is energized, programmed and ready to read a bar code.
Scanning Sequence. A method of programming or configuring parameters for a bar code reading system by scanning bar
code menus.
Self-Checking Code. A symbology that uses a checking algorithm to detect encoding errors within the characters of a bar
code symbol.
Shared Key. Shared Key authentication is an algorithm where both the AP and the MU share an authentication key.
SID. System Identification code. An identifier issued by the FCC for each market. It is also broadcast by the cellular carriers
to allow cellular devices to distinguish between the home and roaming service.
Soft Reset. See Warm Boot .
Space. The lighter element of a bar code formed by the background between bars.
Specular Reflection. The mirror-like direct reflection of light from a surface, which can cause difficulty decoding a bar code.
Subnet. A subset of nodes on a network that are serviced by the same router. See Router .
Subnet Mask. A 32-bit number used to separate the network and host sections of an IP address. A custom subnet mask
subdivides an IP network into smaller subsections. The mask is a binary pattern that is matched up with the IP address
to turn part of the host ID address field into a field for subnets. Default is often 255.255.255.0.