Glossary
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most-significant (bit/word) See leftmost (bit/word).
nesting Programming one loop within another loop, programming a call to a subroutine
within another subroutine, or programming an IF–ELSE programming section
within another IF–ELSE section.
Network Service Board A device with an interface to connect devices other than PCs to a SYSMAC NET
Link System.
Network Service Unit A Unit that provides two interfaces to connect peripheral devices to a SYSMAC
NET Link System.
network support table Tables of settings used to establish operating parameters for SYSMAC LINK
and SYSMAC NET Link Systems.
node One of the positions in a LAN. Each node incorporates a device that can commu-
nicate with the devices at all of the other nodes. The device at a node is identified
by the node number.
node number A number used to identify a node on a network. The node number of a CV-series
PC is called the “unit number” in the PC Setup.
noise interference Disturbances in signals caused by electrical noise.
nonfatal error A hardware or software error that produces a warning but does not stop the PC
from operating.
NOT A logic operation that inverts the status of the operand. For example, AND NOT
indicates an AND operation with the opposite of the actual status of the operand
bit.
NSB An acronym for Network Service Board.
NSU An acronym for Network Service Unit.
octal A number system where all numbers are expressed in base 8, i.e., numbers are
written using only numerals 0 through 7.
odd parity A communications setting that adjusts the number of ON bits so that it is always
odd. See parity.
OFF The status of an input or output when a signal is said not to be present. The OFF
state is generally represented by a low voltage or by non-conductivity, but can be
defined as the opposite of either.
OFF delay The delay between the time when a signal is switched OFF (e.g., by an input
device or PC) and the time when the signal reaches a state readable as an OFF
signal (i.e., as no signal) by a receiving party (e.g., output device or PC).
offset A positive or negative value added to a base value such as an address to specify
a desired value.
ON The status of an input or output when a signal is said to be present. The ON state
is generally represented by a high voltage or by conductivity, but can be defined
as the opposite of either.
ON delay The delay between the time when an ON signal is initiated (e.g., by an input de-
vice or PC) and the time when the signal reaches a state readable as an ON sig-
nal by a receiving party (e.g., output device or PC).
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