Qseven Makes It Possible: Quick Migration to ARM

ARM systems are impressive, with their low power consumption and high graphics performance. However, until now, they have been difficult to integrate. ARM system integration is now much easier through the utilization of turnkey pre-integrated modules (COMs).

ARM Processors Conquer the Embedded World

There are a number of reasons why ARM architecture is well suited for the design of embedded systems. As a RISC (Reduced Instruction Set Computing) architecture with an ultra-efficient instruction set, it offers optimal processor performance with low power consumption. RISC processors, with comparable performance, operate at significantly lower clock speeds than comparable CISC (Complex Instruction Set Computing) architectures such as x86. Superb latent performance and low overhead even at low clock speeds, make them well suited for use in real-time applications. The smaller footprint also means that they are considerably less costly to manufacture.

Many original ARM applications were processing cores in simple controller applications, mostly void of an operating system. The ARM business model of developing the processor technology and then licensing that technology to individual chip manufacturers has led to an overwhelming range of ARM-based system-on-chips (SoCs), often developed for one or two very specific applications. The big disadvantage of this model is that there were virtually no standardized interfaces and new interfaces had to be developed or customized individually for each system. However, there has been a fundamental shift in recent years. First of all, the rapid migration from mobile phones to ultra-mobile high-performance computers has accelerated the development of ARM cores as single-core and multi-core systems with ever increasing clock rates. In addition, systems have become more powerful and more expensive, making a certain degree of standardization and the ensuing potential reusability of developments even more important. A good example is the introduction of complex operating systems such as Linux and Android. Many real-time operating systems, Windows Embedded, and a few versions of Windows 8 are available for ARM today, with future Windows versions targeted to run on both ARM and x86 architectures. In addition to the mobile phone segment, ARM architectures already dominate virtually the entire consumer electronics market from MP3 players to internet-ready televisions. In the industrial sector, ARM rules the tablet PC market and is currently taking over the market for operator terminals and mobile data collection terminals. As ARM architectures continue to become more feature rich and more operating systems are developed to support ARM, it is likely that ARM-based systems will continue to expand into new markets and applications.

High Graphics Performance and Low Power Consumption

Because of its low power consumption and the high processing power, many analysts consider ARM to be the future technology for mobile and ultramobile measurement applications, as well as a large part of medical technology. Easy-to-use and intuitive graphical user interfaces, requiring adequate graphics performance, play an important role in the acceptance of modern devices. This is where current ARM-based multi-core systems are unrivaled: Even though AMD and Intel have beefed up their systems substantially, their x86-based CISC systems use considerably more power for the same graphics performance. Special multimedia processors such as the i.MX6 family from Freescale are a fraction of the cost, plus they are perfectly scalable by varying the number of cores and the clock frequency in an identical pin layout.

Too Good to be True?

All of these benefits were offset by the relatively high cost of needing to assemble one’s “own” SoC. Of course, this is not a problem for large companies that have separate development departments for every niche and annual volume sales in the hundreds of thousands. But what about mid-sized companies, where the expertise is contained in the application and the hardware is only a means to an end?

The Solution: COMs (Computer-on-Modules)

In the x86 world, the module principle has proven itself over the last decade to be a good fit for embedded applications ranging from hundreds of units per year to tens of thousands of units. In this space, standardized COMs with clearly defined uniform interfaces are bought pre-integrated (“application-ready”). The only part of the circuitry that is unique to the designer or the application is the carrier board that houses the necessary I/O connectivity and footprint. The advantage here is that a standardized COM can be purchased and simply mounted on the carrier board, letting developers concentrate on their core competencies. The performance and power consumption of the system can be scaled and updated by simply replacing the COM. In theory, it has been possible in the ARM world to place a project-specific processor and a meaningful assortment of peripheral chips on a modular carrier board, then lead as many processor connections as possible outside of the processor on a plug. However, the problem of high (project-) specific integration costs has at best been mitigated, but not completely solved. Costly Board Support Packages (BSPs) still need to be created.

Figure 1: Prepared for new ARM challenges: Qseven module conga-QMX6 and evaluation carrier board conga-QEVAL

Qseven: Less is More

In most cases, it makes more sense to concentrate on established standards and interfaces which can be pre-integrated by the COM manufacturer. For compact, power-saving mobile and ultramobile applications, Qseven, with its 70x70 mm2 compact form factor, has proven itself in the market since its inception in 2008. Conceived from the beginning as a multi-platform standard, Qseven needed to provide minimal enhancements in 2010 to officially release revision 1.20 for the ARM platform.

Fundamental new features which were introduced as part of version 2.0 last year include support for USB 3.0 and Embedded DisplayPort. In addition, an even more compact form factor “µQseven“, with a footprint of 70x40 mm2 for ultracompact applications, was introduced. Table 1 shows the features currently supported by Qseven and interfaces for both technologies. It’s easy to see the advantages that Qseven provides for newcomers or those switching to ARM, as well as the pre-integrated interfaces available for the x86 world.

Qseven: Who Is Behind It?

At the end of the day, Qseven has been the only established standard on the market to support ARM and x86. During the development of the Qseven standard, especially for ARM, it became clear that existing standards organizations remain focused on existing standards. It no longer became possible to adapt new technologies to needed newer standards in a timely manner. Consequently, the leading technology companies united to form SGET (Standardization Group for Embedded Technology). The goal of SGET is to provide the right framework to be able to standardize new technologies within the embedded marketplace. In practice, this may be board or module definitions, as well as software or mechanical standards. The Qseven specification, which was previously maintained by a simple industry group, has been maintained and developed by SGET since 2012.

What About the Compatible ARM Processor?

After establishing Qseven as an appropriate platform for standardized development, there is still an important aspect that is missing. That aspect is the ARM processor itself, or better yet, a complete family of highly compatible, scalable processors which forms the basis for the module and provides as many of the on-chip interfaces defined by Qseven as possible: PCI Express, SATA, USB, powerful integrated HD-capable high-performance graphics with LVDS and/or DisplayPort, I2C bus, Watchdog, etc. These processors, as deemed necessary in the embedded space, should be available for as long as possible and be suitable for industrial applications.

Driven by the enormous success of the chips installed in smartphones and tablet computers, most chip manufacturers have come to realize the embedded market’s potential. To that end, they have added high-performance universal processors with powerful graphics capabilities to the highly specialized niche CPUs in their ARM portfolios. This move has brought some of the necessary interfaces and features to the market.

Currently, one of the most adaptable processors is the Freescale i.MX6. This family of processors is scalable (1-4 cores, diverse high-performance graphic variants), has long-term availability (10 years or more) and is available in industrial temperature ranges. It also has many of the most important interfaces such as PCIe lanes, CAN bus, and DisplayPort. Other advantages include the embedded application experience of Freescale, which was established in the embedded market as Motorola more than 30 years ago, and the experiences and successes of Freescale’s previous i.MX5 family.

The Result: QMX6 is a Powerful ARM Module in Every Regard

As co-founder of the Qseven standard, congatec kept particular focus on interchangeability of modules between the various CPU platforms from ARM, AMD, and Intel. Interfaces for the following inputs and outputs are available across platforms: Gigabit-Ethernet, 5x USB 2.0, 2x SATA II (3GB/s), 1x SDIO, 1x PCIe 2.0, I²C bus (multi-master, with fast-mode interface up to 400kHz), 1x USB OTG Client and CAN bus. An LPC bus is not required with ARM processors; this is usually used as an option for x86-based platforms, where it can be used for the fully address-compatible and interrupt-compatible RS232 ports. As graphical user interface HDMI v1.4 is supported, once directly and a second time combined with the LVDS channel #0, as well as 24-bit LVDS dual channel up to WUXGA 1920x1200 and HD1080. The second LVDS port supports 18-bit and 24-bit dual channel up to WUXGA 1920x1200. I2S and SPDIF serve as sound interfaces from the PC world. A JTAG debug interface and an optional MIPI CSI-2 camera interface, through an FPC connector, are also available. The position of the additional connector is also specified in the Qseven specification to ensure maximum interchangeability. The maximum power draw of the entire module depends on the type of CPU used (number of cores and graphics) and is approximately 2 watts for a single core and up to 5 watts for a quad core utulizing maximum graphics performance.

Figure 3: Ready in a few minutes: The Qseven ARM starter kit conga-QKIT

Fast Deployment and Migration through Ready-To-Use, Pre-Integrated Components

The available signals found in the Qseven specification provide for interchangeability in most applications, even across CPU platforms (ARM, AMD or Intel). Since the mechanical and thermal interfaces for all Qseven platforms are identical, companies that use Qseven modules can quickly and easily switch vendors without having to worry about mechanical changes, and ARM variants can easily be evaluated as alternatives. The conga-QMX6 includes a universal bootloader (U-boot) and currently supports Android, Windows Embedded Compact 7.0, Linux, and optionally QNX. The integration of additional (real-time) operating systems can be achieved through partner firms.

For newcomers, congatec offers a complete starter kit called the conga-QKIT. The conga-QKIT includes not only a conga-QMX6 Qseven module, but also the compatible conga-QEVAL carrier board and appropriate power adapter and cable set. This allows the developer to put a complete system into service in just a few minutes, using Ubuntu-Unix delivered on a MicroSD card. Standard features of the evaluation carrier board include: 5x USB, 1x Gigabit Ethernet, HDMI and LVDS18/24. For connecting to mass storage, the baseboard also contains 1xSATA and 1xSD-card; the module itself has 1x MicroSD and, as an option, a soldered SSD (eMMC) with up to 8GB for robust applications. In addition, congatec offers baseboards in different form factors and an extension with a sophisticated charging and power management system. The attractive price and ease of integration should help to ensure the rapid acceptance of the ARM platform into the embedded module market.

Summary and Outlook

ARM and Qseven go together perfectly to create reliable, pre-integrated platforms in a short time for mobile and ultramobile systems.

The ARM platform paves the way for the Android operating system, with its wide variety of applications, and allows “trendy” power-saving devices to be quickly developed. With the “application-ready” integration of ARM modules in the established Qseven standard, it is now possible to develop power-saving and user-friendly devices of the highest quality - not just easily, but also cost-effectively and quickly. Broad scalability of the i.MX6 family, long-term availability of at least 10 years, and the “ready-to-use” starter kits from congatec, are solid reasons for choosing this future proof combination.