PROFINET communication model
Capabilities enabled by PROFINET
PROFINET provides:
Read access to device data for controllers and external systems
Write access to device data for controllers
Discovery, configuration, and diagnostics using engineering tools
Types of data
The PROFINET protocol transfers two types of data.
Cyclic data
Transfers I/O data continuously
Operates in real time
Uses a fixed data layout
Acyclic data
Transfers data on request
Uses record indices
Handles parameters, diagnostics, and configuration data
Both cyclic and acyclic communication rely on the device structure defined in the configuration.
Mapping the PROFINET device model
Figure 49. Mapping modules and submodules to slots and subslots
The configured module and submodule structure is represented as slots and subslots in the PROFINET device model.
The controller reads this slot–subslot structure to interpret the device interface.