Standard and custom peripheral cards: A hallmark of the PC/104 architecture

The embedded marketplace has seen many gyrations over the last 20 years. The ever-changing roles and scopes of original equipment manufacturers (OEMs) have created a diverse level of requirements. These shifts place increasing pressure on standards groups to develop and market ever-evolving and pioneering technologies that serve not only short-term needs but, in many cases, long-term viability and upgradability.

As anyone in this business knows, there is no single embedded architecture that can serve all applications with appropriate solutions. Tradeoffs are abundant, and it is not even the industry that defines an architecture’s applicability; rather, that decision is made by the application and level of detail an OEM has time to consider.

Full-up systems have become more complex in functionality. In the past, the OEMs responsible for these systems often worked at the board level and developed their own systems according to the requirements of the end customer. Often these OEMs would also be involved in board-level design and manufacturing. As these systems began to add more functionality, however, the supporting infrastructure also had to expand. This situation ultimately diverted OEMs from their core competencies. Today we see multi-tier levels of OEMs creating various degrees of subsystems with often very specialized functionalities. The ability to quickly provide these embedded subsystems requires an architecture with quick expandability, ease of design, and compactness. To fulfill these requirements, OEMs turned to architectures that were standardized with diverse product offerings and supplier options to mitigate the risks associated with single-point sources.

Since its introduction more than 22 years ago, the PC/104 architecture has thrived and evolved in this changing embedded marketplace. The standardized stackable nature of the PC/104 buses (stackable ISA, PCI, and PCIe to Gen 3) enables OEMs to obtain peripherals from various suppliers, plug them together, and create systems to meet nearly anyone’s needs. The key to PC/104’s success has been the diversity of suppliers of standard and specialized peripheral cards to create functionalities critical to every industry, whether it be defense, security, aerospace, transportation, industrial, communications, or medical.

By taking a quick survey of the PC/104 Consortium’s website and its product selection guide or doing a search on the web one finds functionalities as diverse as RS232/485/422, opto isolation, CAN, LIN, USB 2.0/3.0, high and low speed analog and digital I/O, standard and state-of-the art FPGAs, cellular modem, low and extreme resolution GPS, cFast, ExpressCard, SSD, RF MIMO transceiver, and standard/synchronous/avionic/and isolated PWR. Diverse peripheral cards can also include SATA, mSATA, WiMAX, WLAN, copper and fiber Ethernet, managed/unmanaged LAN Switches, routers, IEEE 1394B/IEEE 1394A, Syncro Resolver, CameraLink, frame and audio grabber, MPEG/H264 Video CODEC, MIL-1553, and ARINC. Moreover, that list doesn’t even mention processor cards using all types of x86, ARM, and PowerPC architectures from the very low power to quad cores and more.

We haven’t even discussed yet all of the custom peripheral cards that have been created in order to meet an OEM’s unique requirements and protect its IP. The simplicity yet versatility of the PC/104 stackable architecture allows these final building blocks to be created, implemented, and integrated quickly and cost-effectively, thereby reducing time to market and overall lifetime product costs. Many industries benefit from the diversity of the PC/104 ecosystem, which offers a variety of embedded solutions from the general to the highly specialized and everything in between (see Figure 1).

Figure 1: The standardized, stackable nature of the PC/104 architecture lends itself to diverse types of peripheral cards, which can be used for such diverse applications as defense and security or communications and industry.
(Click graphic to zoom)

For more information visit the PC/104 Consortium website at