Motorola MK1200, Руководство по продукции

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Glossary - 5
Misread (Misdecode). A condition which occurs when the data output of a reader or interface controller does not
agree with the data encoded within a bar code symbol.
MU. The MU (Mobile Unit) searches for APs with the same ESS_ID and associates with an AP to
establish communications.
Null Modem Cable. An RS-232 cable used to connect two personal computers together in close proximity for file
transfer. It attaches to the serial ports of both machines and simulates what would occur
naturally if modems and the phone system were used. It crosses the sending wire with the
receiving wire.
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).
Open System
Authentication. Open System authentication is a null authentication algorithm.
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%.
PING. (Packet Internet Groper) An Internet utility used to determine whether a particular IP address
is online. It is used to test and debug a network by sending out a packet and waiting for a
response.
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.
Protected Mode. An application can be assigned password protection so that it can only run when a password
is entered. The password can be assigned for a specific application using the RDM, System
Menu or the Control Panel.
Quiet Zone. A clear space, containing no dark marks, which precedes the start character of a bar code
symbol and follows the stop character.
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.
Scan Area. Area intended to contain a symbol.