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National Instruments NI-DNET User Manual

Page 83

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Glossary

NI-DNET User Manual

G-6

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P

PC

personal computer

peer-to-peer

DeviceNet communication scheme in which each device communicates as
a peer and connections are established among devices as needed.

PLC

Programmable Logic Controller

polled I/O

Master/slave I/O connection in which the master sends a poll command to
a slave, then receives a poll response from that slave.

protocol

A formal set of conventions or rules for the exchange of information among
devices of a given network.

R

RAM

Random-access memory

remote

Within NI-DNET, anything that exists in another device of the device
network (not on the same host as the NI-DNET driver).

resource

Hardware settings used by National Instruments DeviceNet hardware,
including an interrupt request level (IRQ) and an 8 KB physical memory
range (such as

D0000

to

D1FFF

hex).

S

s

seconds

scanned polling

A polled I/O communication scheme in which all poll commands are sent
out at the same rate, in quick succession.

sensor

A device that measures electrical, mechanical, or other signals from an
external, real-world variable; in the context of device networks, sensors are
devices that send their primary data value onto the network; examples
include temperature sensors and presence sensors. Also known as
transmitter.

server

In explicit messaging connections, the server is the device to which the
service is directed.