Embedded computing module supports both real-time control and HMI.

Imagine a universal embedded platform suitable for many kinds of industrial applications – one system that seamlessly integrates both a real-time OS and an HMI. In this solution, two previously separate systems are fully functional without restriction and have been combined without any changes to the software. Now imagine that you can put your hands on one – quite literally.

The congatec* conga*-ARkit is a PLC reference platform from congatec AG and Real-Time Systems (RTS) GmbH. It uses a conga-CAx COM Express module built with the ultra-low power, industrial temperature Intel® Atom™ processor Z5xxPT series and the Intel® System Controller Hub US15WPT chipset. The compact form factor ( just 95x95mm²) fits right into a DIN Rail housing slot. It puts out just 5 watts of heat, which means it is ideal for mobile devices. (Yes, you can hold onto it with your bare hands.) And thanks to Intel® Hyper-threading technologyi and a real-time hypervisor, it can simultaneously and reliably run two separate operating systems – including a real time operating system (RTOS) and a general purpose operating system (GPOS).

“It’s a perfect fit” for the automation industry which is facing pressure to reduce costs and energy consumption while improving reliability and performance. “Partitioning a compact and powerful embedded computer module to run two independent operating systems and applications can reduce the hardware cost of a system solution by as much as 50 percent,” says Christian Eder, congatec marketing manager. “And because one machine has a statistically smaller chance of failure than two, reliability goes up when you reduce the number of parts. That makes it a super-efficient platform that’s ideal for both mobile and PLC solutions.

Solution BriefIntel® Atom™ Processor Z5xxPT Series and Intel® System Controller Hub US15WPT

Combined PLC/HMI Computing Module

Industrial Automation

“ It’s the perfect fit.” Compact. Cool. Powerful. Efficient.

Automation Requires Task SeparationVirtualization seems like an obvious solution for keeping these two

systems separate. But traditional virtualization technology uses “tricks”

to simulate separate computing systems for each operating system,

such as time-slicing, emulating hardware or trapping and redirecting

the instructions of the processor. Rotating these functions – without

regard to priority of the task – may potentially interfere with real-time

determinism and could put a control solution off course.

To solve this problem, Real-Time Systems has developed specialized

virtualization technology known as a real-time hypervisor. It enables

real-time performance on a virtualized platform, allowing for a com-

bination of GPOSes and RTOSes to run simultaneously on a single

hardware system.

The RTS* hypervisor does this by partitioning the processor into

individual and independent hardware platforms. In this way each

operating system exclusively owns one or more of the virtual parti-

tions. RTS’ real-time hypervisor also partitions available memory and

assigns it to the individual operating systems. Hardware devices, such

as PCI or legacy devices, are individually configured so interrupts are

routed directly to a specific operating system. Special or modified

device drivers are not necessary because interrupts are assigned

individually and direct hardware access is allowed.

Building the SolutionFor its first fully consolidated PLC/HMI module, congatec chose

the industrial temperature, ultra-low power Intel® Atom™ processor

Z5xxPT series and Intel® System Controller Hub US15WPT. Its size,

performance and thermal output is a perfect fit for the requirements

of an industrial PLC. Because it’s such a small platform that runs at

extremely low power, it addresses industrial demand for mechanically

small sized applications. Barely twice the size of a credit card, it con-

sumes less than 5 watts of power. And because it fits into DIN Rail

housings, it can easily be used in existing PLC solutions as well as new

fanless and ultra-mobile applications.

Like a dual-core processor, this platform supports two operating systems

simultaneously. It has built-in Intel Hyper-threading technology and

Intel® Virtualization Technologyii and therefore provides two logical

cores for running the RTOS and HMI software. PLC manufacturers

can port their existing solutions to this integrated platform without

making changes to the software code. With little effort, this one

hardware platform can easily replace two previously separate systems,

saving space, time and cost.

The conga-CAx module supports the full industrial temperature range

of -40° to +85° Celsius. It features 1 GByte onboard DRAM and an

integrated IDE flash drive with a capacity of up to 8 GByte. There are

no movable components on the module which enables the design of

rugged solutions for harsh environments.

2

Platform Requirements for Multi-Threaded Instruction CodeProcessors must support multi-threaded instruction code

in order to run the RTS Hypervisor. This enables parallel

operation of two independent operating systems without

interference. Depending on the processor, there are two

ways that Intel supports multi-threaded application designs:

multi-core processors, which include multiple distinct logical

cores; and Intel hyper-threading technology, which mimics the

physical configuration of multiple cores using only a single

physical core.

From the perspective of the hypervisor and software, hyper-

threading functionality appears the same as a multi-core

processor and behaves as if it has multiple logical cores. This

enables full partitioning of the processor in order to run the

two logical components: the RTOS and the GPOS (e.g. HMI

solution).

For processors that support multi-threaded instructions in

one of these two ways, performance and power requirements

then become the deciding factors when choosing the solution

for an integrated, all-in-one platform.

Operating System #1Linux*Windows*VxWorks*QNX*

Operating System #2Linux*

Windows*VxWorks*

QNX*

CPULogical Core #1MemoryI/O

CPULogical Core #2

MemoryI/O

Shared MemoryVirtual Network

Real-TimeHypervisor

Multi-Core & Multi-OS System

Figure 1: RTS* Real-Time Hypervisor Stack

Congatec Automation Reference KitCongatec has paired its conga-CAx module with the RTS hypervisor

to deliver a reference design for PLC automation solutions. The kit

contains a complete hardware infrastructure and a fully installed

software package, including the runtime environment. The PLC

handler is entirely independent of the HMI system, so it’s immune to

OS and application failures; such events won’t affect the reliability of

the control.

“Industrial automation customers are under a lot of cost pressure these

days,” explains Eder. “Their core competence is in programming the

controller, not integrating or writing the OS, not building or designing

the hardware. They just want to get out-of-the-box solutions that

they can use as a basis for their system.”

The conga*-ARkit is a modular design that is fully validated and

application ready. It gives PLC manufacturers a single hardware

solution for their PLC and HMI systems, and enables them to focus

development resources on the critical control logic – their core

competency. The platform work has already been done so that

manufacturers can more quickly build and deliver their next PLC. The

nearby diagram depicts the complete conga-ARkit solution.

3

The software stack components of the conga-ARkit include:

• CoDeSys (Controller Development System)

programming language:

CoDeSys enables manufacturers to use a single system for

programming and exchanging data between all compatible

components in the network. Software can be adapted to the

hardware by employing configuration files. This makes it possible to

change all the settings (Memory Model, Memory Layout, CPU, etc.)

without touching source code. Also included is a visualization editor.

Visualization can be engineered in parallel to the control software.

Control and visualization software are then compiled together and

are portable to other hardware platforms.

MicrosoftWindows XP

OSADLLINUX

I/OI/I/OO

EtherCATProtocol Stack

CoDeSys SPRuntime

VirtualEthernet

Hypervisor

IEC 61131-3Programming System

OSCAT Library

Visualization

OPC Server/Client

I/I/I/OOO

pervisorHyp r

COM Express

• OSCAT (Open Source Community for Automation

Technology):

The function library used for CoDeSys.

• EtherCAT Fieldbus:

Ethernet-based fieldbus for hard real-time requirements. I/O devices

will be connected to the system by EtherCAT. The update time for

1000 distributed I/Os is only 30 µs with a jitter of significantly less

then 1 µs. Other fieldbuses like Profinet*, Profibus* DP, CAN* and

others can also be added easily.

• OSADL (Open Source Automation Development Lab):

Promotes and supports the use of open-source software in the

context of machine and plant control systems. OSADL has created

a powerful Real-Time LINUX* distribution which can be operated on

multiple hardware platforms.

• OPC (Open Connectivity):

As a specification for standardizing the communication

between plant floor devices and enterprise systems based on

general computing technology, OPC enables easy integration of

visualization and the user interface through CoDeSys.

Conclusion:Pairing an RTOS and GPOS on a single hardware platform means

industrial automation customers can now eliminate the extra

piece of hardware that used to run the machine controller. Sound

a bit radical? congatec doesn’t think so. In fact, customers are

enthusiastically developing and porting their control solutions to this

new platform.

It’s a win for the cost-pressured industrial segment, enabling anyone

that uses control logic to reduce their hardware costs, shrink the size

and weight of the system, reduce energy consumption, lower thermal

output, and pack more performance into a tighter space. “It’s green

technology,” says Eder. “What could be more efficient and appealing

than that?”

Figure 2: This diagram shows the complete conga-ARkit, with the conga-CAx module, RTS* hypervisor and all the platform-level components that comprise the fully validated and application-ready hardware solution for a converged PLC/HMI solution.

i Intel® Hyper-Threading Technology (Intel® HT Technology) requires a computer system with an Intel® Processor supporting Intel HT Technology and an Intel HT Technology enabled chipset, BIOS, and operating system. Performance will vary depending on the specific hardware and software you use. See www.intel.com/products/ht/hyperthread-ing_more.htm for more information including details on which processors support Intel HT Technology.

ii Intel® Virtualization Technology requires a computer system with an enabled Intel® processor, BIOS, virtual machine monitor (VMM) and, for some uses, certain platform software enabled for it. Functionality, performance or other benefits will vary depending on hardware and software configurations and may require a BIOS update. Software applications may not be compatible with all operating systems. Please check with your application vendor.

This document and the information given are for the convenience of Intel’s customer base and are provided “as is” with NO warranties whatsoever, express or implied, including any implied warranty of merchantability, fitness for a particular purpose, and non-infringement of intellectual property rights. Receipt or possession of this document does not grant any license to any of the intellectual property described, displayed, or contained herein. Intel® products are not intended for use in medical, life-saving, life-sustaining, critical control, or safety systems, or in nuclear facility applications.

Copyright © 2009 Intel Corporation. All rights reserved. Intel, the Intel logo, Intel Atom and Intel Core are trademarks of Intel Corporation in the U.S. and other countries.

*Other names and brands may be claimed as the property of others.

1109/SI/S2D Please Recycle 322760-001US

For more information:

www.congatec.com

www.real-time-systems.com

www.intel.com/go/industrial

http://developer.intel.com/design/intarch/atom500/techdocs.htm