Since the real-time protocol operates with standard on-board Ethernet controllers, the download provides the only free-of-charge complete real-time Ethernet system worldwide. SYS TEC electronic, a systems house for automation solutions and EPSG member, has released its POWERLINK solution under the BSD Open Source license. The software package contains a sample implementation for Linux systems which consists of the stacks for the Managing Node (master) and for the Controlled Nodes (clients). The Open Source implementation reaches cycle times up to 0.5 milliseconds while ensuring high synchronicity.
Other completely software-based solutions, by contrast, such as Profinet RT or Ethernet/IP, provide cycle times ranging from 2 to some 10 ms. With co-processor support, POWERLINK can even reach cycle times of 0.1 ms. The BSD license allows anyone to use, distribute and modify the software and to add development enhancements free of charge. Moreover, any user may integrate the software into products and sell these. Users are not required to disclose the source code of their own adaptations to the stack, as long as they do not remove the copyright notice from developer SYS TEC from the underlying source code.
“This is a groundbreaking move,” explains Anton Meindl, CEO of the EPSG. “In the medium term, Open Source will turn into an important factor in some automation industry branches. Open Source has already gained much greater importance in other European countries like France or Italy, and in China and India.” According to Meindl, machine builders in Germany still view Open Source technologies with some reservation. Decision makers, however, are increasingly finding Open Source products to be based on high-quality, mature technologies, but with a different business model. “Open Source brings about many crucial benefits that users cannot ignore: independence from single suppliers, long product cycles and fast troubleshooting.” Moreover, all market players benefit from open basic technologies: “Users gain a high degree of independence in employing the product, while manufacturers and service providers experience economic growth,” says Meindl.
Background
The Ethernet Powerlink Standardization Group (EPSG) is an independent organization founded in 2003 by leading companies from the drive and automation industry. Its aims are the standardization and further development of POWERLINK, which was first introduced by B&R in 2001. The high-performance real-time communication system is a protocol extension of the IEEE 802.3 Ethernet standard, designed to ensure real-time data transfer on the microsecond level. EPSG cooperates with leading standardization organizations, such as CAN in automation (CiA) and the IEC.
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