Functionality

A PROFINET Controller opens a separate connection (AR = Application Relation) to each individual PROFINET Device for the purpose of data exchange, parameterization, and diagnosis.

The devices are identified by the PROFINET station name. A PROFINET Device is structured by submodules which are addressed by slot/subslot. Therefore, for example, the communication module with the Ethernet interface is module 0 and contains the interface submodule and several port submodules for each Ethernet port. Slot/module are containers for the submodules to which the actual IO data and parameters (data records, addressed via index) are assigned.

In the case of cyclic data exchange, PROFINET follows the provider–consumer model. This means that both the IO Controller and the IO Device send the cyclic data independently on their own. A mutual monitoring of the send clock takes place. Exceeding the allowed limit will cause the connection to be terminated. Together with the actual IO data of a submodule, status information (provider and consumer status) is transmitted in each case.

A PROFINET Device sending alarms to the PROFINET Controller to notify about the coming and going of interruptions. PROFINET defines a comprehensive diagnosis model for this, which includes, for example, hardware defects (broken cable), network interruption, or device-specific events.

Acyclic services (DCE RPC via UDP/IP) are used for the transmission of configuration data, asset data, and diagnosis data.