Pierre Ficheux, Open Wide

Industrial Ethernet is a successor of classic field bus such as CAN, MODBUS or PROFIBUS. POWERLINKwas created by B & R Automation, Austria and provides performance and real-time  capabilities on standard Ethernet hardware.

OpenPOWERLINK is open source and runs on lots of platforms such as Linux, Linux/PREEMPT-RT, Windows, various RTOS and dedicated hardware (FPGA).
Xenomai is a realtime extension for Linux kernel based on co-kernel technology (just like RT-Linux and RTAI). It is much more efficient than PREEMPT-RT on same hardware but more difficult to use as it is based on a kind of "partitioning" with "hypervisor" approach using a micro-kernel called "I-Pipe".

In this paper we will describe openPOWERLINK porting stategy based on RTnet (RT network stack for Xenomai) and "raw sockets" (instead of PCAP on Linux). Then we will compare performances with PREEMPT-RT on same platform and several configurations:

• Full software configuration -> slave (CN) and master (MN) running on Linux or Xenomai
• Real configuration (hard   soft) -> Xenomai and "commercial" POWERLINK hardware as MN or CN

Main target platform  is Freescale i.MX6 (Armadeus APF6 and RIOTboard). Linux distribution is embedded Linux built by Buildroot. We use the new Xenomai 3.