Glossary - 7

N
Nominal. The exact (or ideal) intended value for a specified parameter. Tolerances are specified as positive and negative
deviations from this value.
Nominal Size. Standard size for a bar code symbol. Most UPC/EAN codes are used over a range of magnifications (e.g.,
from 0.80 to 2.00 of nominal).
NVM. Non-Volatile Memory.
O
ODI. See Open Data-Link Interface.
Open Data-Link Interface (ODI). Novell’s driver specification for an interface between network hardware and higher-level
protocols. It supports multiple protocols on a single NIC (Network Interface Controller). It is capable of understanding
and translating any network information or request sent by any other ODI-compatible protocol into something a NetWare
client can understand and process.
P
Parameter. A variable that can have different values assigned to it.
Percent Decode. The average probability that a single scan of a bar code would result in a successful decode. In a
well-designed bar code scanning system, that probability should approach near 100%.
Print Contrast Signal (PCS). Measurement of the contrast (brightness difference) between the bars and spaces of a
symbol. A minimum PCS value is needed for a bar code symbol to be scannable. PCS = (RL - RD) / RL, where RL is
the reflectance factor of the background and RD the reflectance factor of the dark bars.
Programming Mode. The state in which a scanner is configured for parameter values. See Scanning Mode.
Q
Quiet Zone. A clear space, containing no dark marks, which precedes the start character of a bar code symbol and follows
the stop character.
QWERTY. A standard keyboard commonly used on North American and some European PC keyboards. “QWERTY” refers
to the arrangement of keys on the left side of the third row of keys.