Siemens S7-1200 System Manual page 564

Communication
10.2 PROFINET
Example - the I-device as IO device and IO controller
The I-device as IO device and IO controller is explained based on the example of a print
process. The I-device controls a unit (a subprocess). One unit is used, for example, to insert
additional sheets such as flyers or brochures in a package of printed material.
564
S7-1200 Programmable controller
System Manual, 03/2014, A5E02486680-AG