Intermec Janus 2050 User Manual page 404

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Glossary
UPC/EAN Code
A fixed length, numeric, continuous bar code symbology that uses four
element widths. A device that is configured to decode EAN bar codes can
decode UPC, but the reverse is not true. UPC code is a subset of EAN code. It is
a numeric, 12-digit bar code symbology used extensively in retail, particularly
the grocery industry. The character set is 0 to 9. Its maximum character density
is 13.8 numeric characters per inch.
upline
A device that is at the computer end of a connection between a computer and a
device is referred to as being upline. When devices are connected to a
computer, they are connected in a "line." Upline is a direction relative to the
device, in contrast to downline.
upper memory area
The area between the 640K and 1024K. The upper memory area is physically
composed of a 256K flash ROM chip (system flash) and the video memory
chip. Like a PC, this area contains the BIOS and video buffers. The upper
memory area also contains PC card memory and ROM DOS. The 384K upper
memory area maps just above 640K conventional memory.
User-Defined protocol
A custom communications protocol that can be modified to meet specific host
requirements. For example, you can configure User-Defined to act like a Point-
to-Point protocol, except that it requires an LRC and an acknowledgment from
the receiver. You can also define the communications characters such as SOM,
POL, or SEL, or disable these characters by setting them to null.
vertical reading angle
The vertical angle of a laser scanner to a bar code label. The optimum vertical
reading angle is near 20 degrees.
Virtual Wedge
A Reader Services feature that lets the device decode bar codes, making the
device functionally equivalent to a wedge device connected to a PC.
volatile
Refers to memory that is not saved when power is lost or turned off.
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