Function of PROFINET IO
With PROFINET IO, the PROFINET specification now provides an integration model for simple fieldbus devices that corresponds to the usual viewpoint today of distributed I/Os. The components are addressed in the form familiar from the fieldbus environment, integrated in the particular engineering tool (PC WORX, Step 7, etc.) via the device description, and logically assigned to a controller during planning.
Since all Ethernet devices operate with equal rights in the network, the master/slave process of fieldbus technology becomes a provider/consumer model with PROFINET IO. The provider is the transmitter who sends unsolicited data to the communication partners, the consumers, who then process the data.
In the framework of PROFINET IO, a difference is made between the following roles:
. I/O controller
. I/O device
. I/O supervisor
. Parameter server
IO controller
device that is addressed via the particular I/O devices connected.
I/O device
distributed field device that is assigned to one or more I/O controllers and that transmits not only process and configuration data, but also alarms.
I/O supervisor
A programming device or an industrial PC and has access to all process and parameter data like the I/O controller.
Parameter server
For providing parameter data to PROFINET devices.
There are application relationships between the I/O controller, I/O supervisor, the parameter server and the I/O devices that contain various communication relationships for the transmission of configuration data (standard channel), process data (realtime channel) and alarms (realtime channel).