SEGGER emNet supports Siemens’ smart Ethernet-APL field devices for the process industry

As more devices become connected to the network, a wider, real-time view of the plant is available through management systems. Optimization based on the collected data delivers significant productivity gains while reducing operating costs and energy consumption.

An extended physical Ethernet layer and SEGGER’s IP stack emNet lay the groundwork for future smart field devices from Siemens, one of the largest suppliers of sensors and actuators for the process industry.

To achieve the vision of connecting all sensors and actuators, there are system engineering challenges as some of these devices are limited in electrical power and space when in explosive environments. In particular, the power supply output on an APL spur (connecting APL field switches to the field devices, see Figure 2) is limited to 540 mW at 15 VDC. This power limitation and the requirement to fulfill ex-requirements for an intrinsically save device makes the use of an ultra-low-power (ULP) microcontroller mandatory. To maximize power savings, ULP MCUs are resource-constrained: They typically do not have an integrated MAC, and are constrained to lower clock frequencies and smaller memory footprint.

emNet offers easy integration without configuration effort. Its design, specifically targeted at embedded devices, makes it highly efficient in terms of packet processing speed. This means that even small, low-frequency microcontrollers deliver excellent network performance.

An example for performance-optimizing features of emNet is UDP flood protection. This feature helps to save execution time on incoming data that is to be discarded anyway. If the device is part of a crowded network, this optimization frees up CPU time for other tasks. In this blog article, you can find more details on this topic.

Last but not least, emNet’s flexible PHY driver layer provides support for virtually any Ethernet PHY transceiver. A generic PHY driver compatible with almost all single-port PHYs on the market that follow the IEEE 802.3u standard is included in emNet. Support for other PHY-like devices such as Ethernet switches is also possible. Please check out SEGGER’s emNet website for more technical details and performance analysis.

Ethernet-APL will dramatically change the industry by greatly improving operational efficiency through seamless Ethernet connectivity to field-level assets. 10BASE-T1L solves the challenges that have previously limited the use of Ethernet in field assets. These challenges include power, bandwidth, cabling, distance, data islands, and intrinsically safe Zone 0 (hazardous area) applications. By solving these challenges in both retrofit and greenfield installations, 10BASE-T1L enables new insights into plant health that were previously unavailable and communicates them seamlessly to the control plane and to the cloud or a private server. These new insights open up new opportunities for data analytics, operational insights and productivity improvements through a converged Ethernet network from assets in the field, also to the cloud or private server.

To make Industry 4.0 a reality for the process industry, SIEMENS will provide smart field devices. They include a MAC/PHY chip and an ultra-low power microcontroller, running SEGGER’s emNet as the best available IP stack that combines lowest power consumption with the highest reliability.