Motorola DS3578 Product Reference Manual page 417

SPP. Serial Port Profile.
Start/Stop Character. A pattern of bars and spaces that provides the scanner with start and stop reading instructions and
scanning direction. The start and stop characters are normally to the left and right margins of a horizontal code.
Substrate. A foundation material on which a substance or image is placed.
Symbol. A scannable unit that encodes data within the conventions of a certain symbology, usually including start/stop
characters, quiet zones, data characters and check characters.
Symbol Aspect Ratio. The ratio of symbol height to symbol width.
Symbol Height. The distance between the outside edges of the quiet zones of the first row and the last row.
Symbol Length. Length of symbol measured from the beginning of the quiet zone (margin) adjacent to the start character
to the end of the quiet zone (margin) adjacent to a stop character.
Symbology. The structural rules and conventions for representing data within a particular bar code type (e.g. UPC/EAN,
Code 39, PDF417, etc.).
T
Tolerance. Allowable deviation from the nominal bar or space width.
U
UPC. Universal Product Code. A relatively complex numeric symbology. Each character consists of two bars and two
spaces, each of which is any of four widths. The standard symbology for retail food packages in the United States.
V
Visible Laser Diode (VLD). A solid state device which produces visible laser light.
Glossary - 7