The DF PROFINET IO board operates as a PN IO controller and/or as PROFINET IO device. Because its efficiency is so huge the new board achieves as PN IO controller operations of 64 PROFINET devices per millisecond in the performance class RT. A second independent Ethernet interface is optionally available, so the board can therefore operate as PROFINET IO device at the same time. A stand-alone operation, such as PN IO device is also possible. In PN IO controller mode, among the cyclic data traffic, all acyclic read/write/diagnosis and alarm functions are supported and of course compatible to the PN IO standard of PROFIBUS & PROFINET International. The size of the process image of the card’s I/O data is 16 Kbyte (8 Kbyte input and 8 Kbyte output data). The PROFINET configuration data is stored in a failsafe flash type memory.