Profinet Communication Services - Omron PROFINET NX-PNC202 User Manual

1 PROFINET IO Technology
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PROFINET communication Services

The IO Controller establishes a connection to its IO Devices based on the configuration which has been
given by the user. The Application Relation (AR) includes all data needed to achieve this data
exchange. A single AR can include multiple Communication Relations (CRs). For implementation of dif-
ferent communication profiles, such as PROFIdrive, the PROFINET IO contains special addressing ele-
ments. These elements are called Application Process Identifier (APIs).
The following CRs are possible for each API.
• IOCR, consisting of input, output or multicast
• Record data CR for exchange of acyclic data
• Alarm-CR for communicating alarms and other events
The data exchange between the IO Device and the IO Controller occurs in a poll cycle as configured by
the IO Controller. The user is capable to set this update cycle in the IO Controller configuration for each
of the IO Devices. This results in mutual monitoring of functional operability (watchdog function). All
cyclic data is provided with a status that encodes the validity of the data.
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NX-series PROFINET Coupler Unit User's Manual (W623)