Proving the Business Case for the Internet of Things

Port expands SoM offering for real-time Linux use

Steve Rogerson
May 30, 2019



German company Port is expanding its system on module (SoM) offering for real-time communications using Linux. The IoT and Industry 4.0 module has Profinet CCB and Ethernet IP on board and can now be integrated into Linux environments.
 
The real-time communications module is said to provide cost effective and easy to integrate communications. Profinet CCB and EthernetIP, with Ethercat and Canopen on request, are available in one module.
 
Tools for management, integration and design reduce development and integration times. An integrated update service keeps users up to date.
 
The module is for use with various Ethernet ports such as RJ45 and mini RJ45 (IP20 applications) as well as M12 or M8 (IP54 applications). The phys and transformers are already available on board, so only the SoM module and the corresponding Ethernet connectors have to be integrated on the host module.
 
The SPI of the SoM-RIN32M3 module is supposed to connect the module to the external application processor. Due to the independence between the module clock and the clock of the external application processor, the serial transmission with the SPI interface in asynchronous mode is performed by three module pins.
 
The application controller as SPI master determines the SPI communications mode. The SPI data format can first be switched between MSB and LSB. The number of bits in each transmission can be changed to any number from 8 to 16 or to 20, 24 or 32 bits. The communications are based on a 128byte transfer buffer that can transport multiple requests.
 
The communications are based on a cyclic scheme in which process data can be transmitted cyclically with each request of the application control. Non-real-time communications use the same transport, but processing is decoupled from real-time communications. Thus real-time data can be exchanged independently of function calls of the API.
 
The SoM works with any Linux system that provides an SPI interface as well as an I²C interface via the kernel. Furthermore, high precision timers are needed.
 
Port offers a SoM evaluation platform that can be tested together with a Raspberry PI under Linux. The evaluations board has a PMod-Arduino interface and can thus be combined with other evaluation boards.