PROFINET is becoming the leading industrial Ethernet protocol in automation due to its high-speed: deterministic communications and enterprise connectivity. However: as the world’s most popular fieldbus: PROFIBUS’s importance and usage will continue for many years due to legacy investment protection. Recognizing the hybrid attribute in process plants: this reference design is integral for the migration of existing fieldbus technology into a real-time Ethernet network based on the Programmable Real-Time Unit and Industrial Communication SubSystems (PRU-ICSS) of Sitara™ AM57x processor. This design demonstrates PROFIBUS master and PROFINET IRT device on AM572x with protocol stacks simultaneously running on an ARM Cortex-A15 core while the entire PROFINET switch and PROFIBUS frame handler are executed on the two PRU-ICSS: respectively. The migration scheme is generally also suitable for other fieldbus and industrial protocols.