COM Express — In the Market and Thriving

By Nicole Freeman, Technology Editor

In July 2005, PICMG released the computer-on-module standard for the embedded market. The standard, dubbed COM Express, is aimed a variety of vertical embedded applications. System designers who require upgradeable host functionality have been given flexibility in creating their standard form factor boards. COM Express supports interfaces that will provide a smooth transition path from legacy parallel interfaces to low-voltage, differential-signaling (LVDS) interfaces. These include PCI Express, PCI Express Graphics, Serial ATA, Serial Attached SCSI, USB 2.0, LVDS, Serial DVO (digital video out), Ethernet, and GPIO. Support for PCI and parallel ATA further ensures that OEMs have a smooth transition path from existing systems.

A computer-on-module, or COM, is a small-footprint, single-board computer or mezzanine computer board that's either 95mm-by-125mm or 155mm-by-110mm. The module comes with all the components necessary for a bootable host computer, is packaged as an off-the the-shelf component, and used for the construction of single-board computer solutions. System expansion and customization is carried out through application-specific carrier boards. COMs are small and rugged—designed to fit where other solutions don't, either mechanically, economically, or functionally.

If You Build It…

OEMs are constantly looking to improve efficiency, time-to-market, and bottom line revenues. More importantly, they must rapidly respond to demand fluctuations—a growing reality in today's businesses—by efficiently modifying existing designs. COM Express lets OEMs choose from a large base of compliant products with the confidence that they can incorporate the modules with their latest technology.

While the COM methodology has become an accepted alternative for implementing embedded solutions, the foundation has been laid to replace parallel and bus interfaces entirely by LVDS interfaces. However, most legacy modular form-factor standards have no room for LVDS interfaces, leading to many incompatible COM products.

The demand for small, flexible form factors is growing exponentially, especially in the ever-shrinking size of mobile devices, gaming platforms, and military equipment. But as their size gets smaller, the demand for increased computing power and low energy consumption gets larger.

By formulating an open industry standard, applications that require better performance and I/O bandwidth in small form factors can be developed—products that PCI-X and AGP cannot satisfy. COM Express specifies a small footprint, interoperability for all performance segments of the embedded industry, and use of the PCI Express system bus and Serial-ATA storage interface. The trick is creating a standard that allows for flexibility of design while fixing key requirements to ensure wide adoption.

The benefits for developing products for COM Express are myriad. OEMs see cost reduction through standardization and design reuse. The standard protects against obsolescence, preserves development investments, and reduces the total cost of ownership. The balanced architecture provides for high-performance processing, I/O, and memory, while the compact footprint allows for easy integration. Developers can shake off legacy designs and see a clearer path to develop emerging technologies. Finally, the COM Express standard boasts broad industry participation.

…They Will Come

Standards are all well and good, but mean little without products in the marketplace to support them. In supporting the COM Express standard, the Intel® Communications Alliance is pushing forward the idea of reusability through modular computing. Since the standard's inception in 2005, Intel Communications Alliance members have been quick to release small form factor COMs in compliance with the COM Express standard.

Announced in February 2005, the RadiSys Procelerant CE 915GM COM Express modules combine the Intel® Pentium ® M and Intel® Celeron® M processor performance with serial differential I/O technology. Paired with a RadiSys Procelerant CR carrier board, Procelerant CE COM Express modules provide a ready-to-use development platform.

Released in February 2007, Kontron's update of its ETXexpress-CD computer-on-module to now supports the Intel® Core™ 2 Duo processor. Built around the energy-efficient Intel processor, the COM Express compliant ETXexpress-CD is designed as an improvement for use in small embedded applications that are temperature and power sensitive.

Also announced in February 2007, ITOX's G5C900-B-G COM Express compliant module uses the Mobile Intel® 945GM Express chipset supported under Intel's embedded architecture program. Designed to accept a wide performance range of Intel mPGA 479 packaged processors, including the Intel® Core™ Duo, Intel® Core™ Solo, Intel® Celeron® M, and Ultra Low Voltage Intel® Celeron® M processors.

Launched in January 2005, Fujitsu's PFU Ltd., the Plug-N-Run G4 modules are compatible with Intel® Pentium® M and Intel® Celeron® M processors and support dual channel memory configurations using dual DIMM sockets for up to 2GB DDR2 memory expansion.

February 2006 saw the announcement of Switzerland's Digital Logic's smartModule Express SMX945-L2400. The PC module is based on the Mobile Intel® 945GM Express chipset, runs Intel® Core™ Duo Processor L2400 and features high-end video performance, including HDTV support.

In September 2005, IBASE released its ET810 COM Express module based on the Mobile Intel® 915GM Express chipset. The module supports Intel® Pentium® M and Intel® Celeron® M processors with speeds up to 2.0GHz and can accommodate up to 1GB of DDR2 DRAM. Its advanced graphics capabilities are based on the Intel® Graphics Media Accelerator 900 that supports CRT display and dual channel LVDS interface.

In January 2007, the company announced the ET900, a low-power CPU module using the Mobile Intel® 945GM Express chipset and the latest Intel® Core™ 2 Duo processors. ET900 allows for flexible expansions of six PCI-E x1, one PCI-E x16, and four PCI slots.

In June 2006, Taiwanese company Portwell, announced its PCOM-B210VG and PCOM-B211VG modules. Both modules are based on the Intel® 915GM Express and Mobile Intel® 945GM Express chipsets and support the PCI Express expansion interface as well as Intel Pentium M, Intel Celeron M, Intel Core Duo, and Intel Core Solo processors.

Promises, Promises

Development and adoption of these products and more, both within the Intel Communications Alliance and without, will produce a positive ripple effect. As more products come on board, the way is cleared for development of supporting products, such as off-the-shelf carrier boards, thermal solutions, software and firmware, and enclosures. As off-the-shelf SBC solutions, COM Express adopters can offer standard or specialized I/O, LVDS technology, and platform scalability as well as up-to-the-minute CPU.

The bottom line: Get to market faster with COM Express compliant modules than with traditional, single-board computers.

Nicole Freeman has extensive experience with both technology oriented online and print publications. She is currently an editor for the AlwaysOn Network (www.alwayson-network.com). Her past experience includes positions as managing editor for Embedded System Programming magazine, Software Development magazine, and several other high-tech books.