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Publication 1747-6.5.5 - August 2000
P-6 About This User Manual
Terminology
This term Means
Bridge The scanner module’s support of explicit message transfer.
Change of State A type of I/O data communication. The scanner module can send and
receive data with slave devices that have the change of state feature. Data
is sent whenever a data change occurs. Data is updated at the rate of the
heartbeat.
Cyclic A type of I/O data communication. The scanner module can send and
receive data with slave devices that have the cyclic feature. Data is only
sent at a user-configurable rate.
Dual Mode The scanner module is in dual mode when it serves as a master to one
or more slaves and as a slave to another master simultaneously.
EDS Electronic Data Sheet. A vendor-supplied template that specifies how
information is displayed as well as what is an appropriate entry (value).
Explicit
Messaging A type of messaging used for lower priority tasks, such as configuration
and data monitoring.
Heartbeat Rate Devices that are configured for change of state data can also send a
“heartbeat” signal to indicate proper operation.
Host Platform The computer on which the application software is run.
I/O An abbreviation for “input and output”.
Implicit
Messaging The type of messaging used for high priority I/O control data; e.g.,
change of state, cyclic, polled, or strobed.
Input Data Data produced by a DeviceNet device and collected by the scanner
module for the host platform to read.
MAC ID The network address of a DeviceNet node.
Network The DeviceNet network or the RSNetWorx for DeviceNet software
representation of the network.
Node Hardware that is assigned a single address on the network (also
referred to as a “device”).
Offline When the host platform is not communicating on the network.
Online When the host platform is configured and enabled to communicate on
the network.
Output Data Data produced by the host platform that is written to the scanner
module’s memory. This data is sent by the scanner module to DeviceNet
devices.
PC Abbreviation for an IBM
®
compatible personal-computer.
Polled A type of input/output-data communication. A polled message solicits a
response from a single, specified device on the network (a
point-to-point transfer of data).
Processor The SLC 500 programmable controller.
Record The node address and channel-specific memory assigned in the scanner
module’s non-volatile storage for a node in the scanlist.
Rx An abbreviation for “receive”.
Scanlist The list of devices (nodes) with which the scanner is configured to
exchange I/O data.
Scanner The function of the 1747-SDN module to support the exchange of I/O
with slave modules.
Slave Mode The 1747-SDN module is in slave mode when it is placed in another
1747-SDN module’s scanlist as a slave device.