Networking: Bandwidth hungry applications get fed at ESC
San Jose, CA —If any one issue stood out as commanding the greatest share of mind for attendees and vendors at the Embedded Systems Conference (ESC) here in San Jose, CA, last week (April 3-5, 2007), it has to be 'interconnectedness.' That is, the ability of embedded control devices, from the lowliest sensor to enterprise-level integrated systems, to link rapidly, robustly and flexibly together. It's not just networking per se, although the buzz surrounding Zigbee, USB, Ethernet, and other physical layer standards was quite high. The general issue of how to pass digital signals between embedded-system components seemed to come up in nearly every conversation.
Freescale Semiconductor dropped the first rock into the proverbial pool by introducing a semiconductor device intended to solve the 'last mile' problem for broadband wide-area-network (WAN) communications by making fiber-to-the-home economical. Priced at around $30 in quantity, the MSC7120 integrates a Power Architecture CPU, a StarCore DSP and a data-path engine in a single, multi-core device that the company claims is the first voice-enabled gigabit passive optical networking (GPON) SOC IC. GPON allows delivery of enough bandwidth to carry all the bandwidth-hungry communications services, such as video on demand, now stopped by the bottleneck of limited bandwidth through the last mile to the home.
This 'last mile' problem has been a spectre haunting telecommunications developers for decades. While plenty of bandwidth has been available via packet-based digital transmission over optical fiber at the exchange level and above, installing fiber links over that last mile to the home or small business outside wall has been cost prohibitive and technically difficult. We heard estimates of the bandwidth required to carry all of the triple-play (voice, video and data) services demanded by (but not yet served to) the average home ranging from 39 Gb/s to 55 Gb/s! One company spokesman flatly stated that the new integrated circuit makes this last-mile problem a thing of the past.
What that does for the embedded systems community is make broad band LAN technology ubiquitous throughout industrialized societies. A spokesperson for Microsoft.Net described a vision of small-outline devices, such as wristwatches and TV remote controls, all carrying embedded intelligence (running software written in C# using the company's Microsoft.Net Micro Framework development environment, of course) and communicating through a LAN.
For example, an (intelligent) clothes dryer can tell (by analyzing data from its internal temperature and humidity sensors) that it's almost time to pull the permanent-press shirts out and hang them to avoid wrinkling. It checks and sees that the only human in the house is flipping channels on the television. Instead of sitting in the basement sounding a buzzer—which may or may not be heard over the TV several rooms away—it sends a message to the TV remote control alerting that person to the imminent need to unload the shirts.
Far from being science fiction or wishful thinking, such products are in development or even deployed today, with application including industrial machine-to-machine communications. At ESC, Digi International introduced what it claims to be the first Ethernet networking solution for .Net Micro Framework in the form of the Digi Connect ME JumpStart Kit. The company says that the development kits make it 'easy, fast, and economical' for engineers to develop network-connected devices for industrial automation, building automation, point-of-sale, medical, and other applications.
Network communications have broken the introverted embedded system applications of yesteryear out of their shells. Serious embedded applications now seem to call for distributed systems made up of multiple embedded nodes coordinated through various high-speed serial networks.
The high-volume buzz still emanates from wireless, with Zigbee making the most noise of all. WiFi is already de rigeur for single-board computer (SBC) standard products, just as it is for laptops. It's generally there, whether you need or want it or not. Introductions at ESC started sporting Zigbee in the same vein. Even the little RabbitCore family from Rabbit Semiconductor got WiFi and Zigbee siblings with ESC introductions of the RCM4400W and RCM4510W modules. Still with the tiny RabbitCore 47 x 72 x 13 mm form factor, the RCM4400W features 802.11 (WiFi) and the RCM4510W features 802.15 (Zigbee) connectivity to complement the existing RCM4200 with 10/100Base-T Ethernet.
For those who think Zigbee is overkill and LANs are just too big, Nordic Semiconductor introduced the Ant SensRcore 2.4 GHz wireless sensor network development platform, which the company touts as a solution for personal area networking (PAN)! Like Zigbee, Ant works by passing messages from nearest neighbor to nearest neighbor until messages reach their targets, and nodes automatically sense their nearest neighbors to set up the network topology on an ad hoc basis. Unlike Zigbee's more complex mesh networking protocol, Ant networks have a single clearly defined path from each message-originating node to each target. The protocol's strengths are low power use (2
To be sure, interconnectedness was not the only theme at ESC. Look for coverage of other important themes, such as developments in tools for software development and validation, to appear in Control Engineering online and print publications in the coming weeks.
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For more information, visit the Embedded Systems Conference website .