Rockwell Automation 2755 AdaptaScan Bar Code Readers - Manual (Page 87)

Glossary G–9
Q
quiet zone
Spaces preceding the start character of a symbol and following the
stop character. Sometimes called the clear area.
R
read
A condition in which an entire package is decoded.
reader
A device comprised of a scanner and a decoder.
RS-232C
An EIA standard that specifies electrical, mechanical, and functional
characteristics for serial binary communication circuits in a
point-to-point link.
RS-422
An EIA standard that specifies electrical characteristics of
balanced-voltage digital interface circuits in a point-to-point link.
RS-485
An EIA standard that specified electrical characteristics of
balanced-voltage digital interface circuits in a multi-point link.
S
scan
The search for a symbol or marks which are to be optically
recognized.
scan area
The area intended to contain a bar code symbol.
scanner
An electronic device to acquire and convert reflected light from the
bars and spaces of a symbol into electrical signals for processing by
the decoder.