5 Acyclic Communication (DP-V1)
PROFINET offers cyclic communication to enhance the
cyclic data communication. This feature is possible via an
IO controller (for example PLC), as well as an IO supervisor
(for example PC Tool).
Cyclic communication means that data transfer takes place
all the time at a certain update rate. It is a common
function used for quick update of I/O process data. Acyclic
communication means a one-time event, used mainly for
read/write on parameters from process controllers, PC-
based tools, or monitoring systems.
5.1 Features of an IO Controller System
Cyclic data exchange.
Acyclic read/write on parameters.
The acyclic connection is fixed and cannot be changed
during operation.
In general, an IO controller is used as process controller,
responsible for commands, speed reference, status of the
application, and so on (PLC or PC-based controller).
In the IO controller, the acyclic connection can be used for
general parameter access in the slaves.
5.2 Features of an IO Supervisor System
Initiate/abort acyclic connection.
Acyclic read/write on parameters.
The acyclic connection can be established dynamically
(initiated) or removed (aborted) even though an IO
controller is active on the network.
The acyclic connection is typically used for configuration or
commissioning tools for easy access to each parameter in
any slave in the system.
Acyclic Communication (DP-V...
Programming Guide
MG06G102
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Summary of Contents for VLT AutomationDrive FC 360
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