Open Doors for Universal Embedded Design



Charged with finding cost-effective integration for multicore platforms, the European Union’s (EU) Artemis EMC2 project finished at the end of May this year. A further initiative with CERN could mean the spirit of co-operation and the principles of open hardware herald an era of innovation.

The aim of Embedded Multicore for Mixed Criticality applications in dynamic and changeable real-time environments (EMC2) was to find embedded multicore systems which can be used in safety-critical systems, conventionally served by single-core processors.

It seems an obvious objective—a single, integrated computing platform, where multicore platforms can be used across different applications. The mixed-criticality element of the title refers to the fact that the embedded multicore systems have to be stable.

The Need for Multicore Embedded Systems
The majority of critical software applications run on a single processor as it is easier to review the code and debug a single processor than multiple ones. For commercial personal computers (PCs), phones, and file servers, however, multiprocessors are predominantly used, as they help share the workload. In the industrial sector, the critical features and functions rely on single core processing.

Figure 1: The EMC² Project is an EU-funded initiative designed to deploy multicore systems in critical applications. The prevalence of commercial products meant that there were very few single-core processors available. Developers added software to the silicon on-board for critical applications which had a multicore processor or system on chip (SoC) to bypass the processor.

Figure 1: The EMC² Project is an EU-funded initiative designed to deploy multicore systems in critical applications. The prevalence of commercial products meant that there were very few single-core processors available. Developers added software to the silicon on-board for critical applications which had a multicore processor or system on chip (SoC) to bypass the processor.

Infineon Technologies proposed a project for embedded multicore systems in 2012. The resulting EMC² project is a collective of 98 companies from 19 European countries. Its intent is to “force the breakthrough and deployment of multicore technology in almost all application domains where real-time and mixed-criticality are issues,” to boost the competitiveness of Europe’s embedded system industry.

EMC² is an Advanced Research & Technology for Embedded Intelligent Systems (ARTEMIS) project, the European Union (EU) organization made up of small to medium enterprises (SMEs), research organizations, and manufacturers to promote embedded intelligent systems.

“The objective of EMC² is to establish multicore technology in all relevant embedded system domains,” says its website. Embedded systems are the information and communications backbone across systems, but the varied system types, with different functions make it a fragmented landscape. This project aims to make multicore computing platforms that “significantly improve systems and applications, integration, efficiency and performance.”

The EMC² project finished on May 31, and members are collating findings now to publish in white papers later this year. One of the distinguishing features is that EMC2 advocates an open environment for sustainable systems, with scalable, flexible systems that can be adapted and configured, and shared by the community.

Figure 2: Pictured left is the EPIC form factor, center is a stacked board with PCI mini cards for wireless connectivity, right is the EMC² board. (Courtesy Sundance)

Figure 2: Pictured left is the EPIC form factor, center is a stacked board with PCI mini cards for wireless connectivity, right is the EMC² board. (Courtesy Sundance)

One of the companies involved in EMC² is Sundance Microprocessor Technology, the UK-based company that specializes in embedded modules and boards. Its role was to develop a multicore hardware architecture, according to the guidelines laid out in the sub-group, dedicated to ‘Multicore hardware architectures and concepts.’ This group was tasked with developing and evaluating hardware techniques that enable multicore processors to ‘execute applications with mixed criticalities.’ It identified that most modern architectures, although increased in complexity, delivered only a relatively small improvement in performance. This has led to an increase in design complexity, verification and runtime behavior, to such a point that a programmer cannot understand the impact code will have on runtime behavior, hampering the construction of mixed-criticality systems, “especially ones that are scalable and heavily connected.” Sundance Managing Director, Flemming Christensen, explains: “Sundance had to design a platform that was as modular as possible and design a platform which could be expanded using whatever products are commercially available.” This could be particular components for a space project, for example, where a lot of audio channels are needed. “We couldn’t do everything on the budget available,” continues Flemming, “so we decided to make it as modular as possible and to use soft processor cores inside an FPGA, or hard processor cores.”

Sundance selected Xilinx’s Artix-7 and Kinetix-7 FPGAs for its EMC²-DP hardware platform. The EMC²-compliant PC/104 OneBank Carrier for SoC modules can be used in rugged environments for commercial, medical, industrial, and military applications. “The idea is you can take a board, put an ARM processor on it, and the ARM processor can run as a software processor. You can have a multicore system by either adding more of the same boards, so they can be stacked, making the PCI Express the communications interface between the boards, or you can combine, perhaps a single processor core and a large FPGA, and use an Intel central processing unit (CPU), as there are plenty of Intel CPUs available for the PC/104 world,” says Christensen.

Figure 3: A demonstration by the Institute of Information Technology and Automation (UTIA) using EMC²-DP for asymmetric multiprocessing (Picture – UTIA)

Figure 3: A demonstration by the Institute of Information Technology and Automation (UTIA) using EMC²-DP for asymmetric multiprocessing (Picture – UTIA)

The board connects to a PC host or an ARM host or can be FPGA-only, if desired. Christensen cites one application using the board where multiple cores were added inside the FPGA: “They were not using any conventional CPUs, they are using processors that are resident inside an FPGA, small 8-bit FPGAs, something very simple,” he explains. “They don’t take up a lot of space, but they are still running a mission-critical infrastructure. These kinds of things will eventually become an application and it will not run on one of our boards, but will be ported and become an application specific integrated circuit (ASIC),” says Christensen.

The Choice of PC/104
The decision to base the EMC²-DP on the PC/104 format stems from the form factor being one of the smallest available, as well as stackable. “What is very important,” says Christensen, “is that PC/104 offers a PCI Express stackable system, so it provides the option of adding multiple boards to the system by using a single board.” That, says Christensen, is the backbone of what EMC² is trying to achieve, the ability to add processor boards, and I/O boards from a number of vendors which still communicate on the PCI Express backbone. PC/104 has the OneBank connector system which allows the board to be scaled up in any shape or form. “As the technology includes switching,” adds Christensen, “we can also switch the backplane.” This is an advantage over a rack-based system, he points out, as all the switching takes place on the PC/104 board, negating the need for a backplane. This also means that the system can be made smaller, and cost less, due to the backplane saving.

The use of the PC/104 form factor also lends itself to versatility, maintains Christensen. It allows a project to create a system, starting with five or six boards, but which after a series of iterations may only need three or four boards. These three or four boards will be the ones you end up integrating inside a box, says Christensen, rather than being plugged into either a PC or backplane. “If you have eight boards to start with and have chosen an eight-slot carrier board, you are stuck with it, you cannot make it smaller, because of the backplane. . . what you could do five years ago with eight slots, you may only need three now. The PC/104 form factor allows you to redesign, keep the same enclosure but shrink it very easily simply by making the box smaller because you do not have this big backplane,” he says.

Target applications are machine automation, robotics, and deep learning, or artificial intelligence. “We tend to focus on vision sensors,” says Christensen, “because that is where the bandwidth of the processing power is required,” he reasons. Vision automation systems require multiple sensors, multiple video interfaces, and fast processing of video data to learn from what they see and make decisions based on that knowledge.

Open Hardware Repository

Sundance has placed the EMC²-DP on the CERN (Conseil Européen pour la Recherche Nucléaire, or European Council for Nuclear Research) Open Hardware Repository. This is a resource, based on the same principle as open software, but for hardware. It was created to allow designers to collaborate on open hardware designs. Members can download all electronics, schematics and manufacturing files, download and order a PCB and build a board without paying a license fee. The technology can be developed into an application; the only condition is that whatever a designer develops has to be placed on the Open Hardware Repository for the community to access.

Christensen confesses his interest here. “This is my personal push [as technical chair of the PC/104 Consortium],” he says. “The consortium has always been tailored for all specifications to be free and open to use, as well as able to be copied and modified—and without charge. The CERN initiative is parallel to what the PC/104 Consortium is all about—allowing engineers to copy something and make it better.”

This collaboration is a new initiative. The PC/104 Consortium will provide design-in examples of new and mature boards, with a reference design, for others to use and create something new. Although the Sundance board is the only PC/104 product on the CERN Open Hardware Repository, there will be more news in the summer, promises Christensen. “My goal is to get five designs within the first year,” he says, and he is actively working to promote to PC/104 Consortium members that there is a place where they can download—and upload—reference designs which are PC/104-compatible.


hayes_caroline_115Caroline Hayes has been a journalist covering the electronics sector for more than 20 years. She has worked on several European titles, reporting on a variety of industries, including communications, broadcast and automotive.

Share and Enjoy:
  • Digg
  • Sphinn
  • del.icio.us
  • Facebook
  • Mixx
  • Google
  • TwitThis

Tags: