Advances In Embedded Systems Cultivate Connectivity And Development Tools

Pervasive networking permeates this week's Embedded Systems Conference in San Francisco, Calif., as revealed by technical presentations and exhibited products touting advances in many networking standards. One such advance waiting in the wings, the IPv6 standard, is an enhancement of TCP/IP, the king of all Internet protocols found in most operating systems (OSs). Also, the Extended Markup Language (XML) and Simple Object Access Protocol (SOAP) data-exchange standards are expected to improve interoperability atop TCP/IP.

Products like Jabber.com's Jabber server highlight a trend toward centralized, Internet-based services with distributed and sometimes embedded clients, from desktop and handheld PCs to embedded set-top boxes and headless embedded-control systems. The first commercial release of the XML-based Jabber server complements the existing open-source jabber.org instant-messaging (IM) server. This works with desktop clients and portable handheld devices running environments such as Transvirtual's PocketLinux (Fig. 1).

Jabber's ability to act as a gateway to AOL's AIM and other IM services is a distinct advantage. But the ability to add server plug-ins that use XML's extensibility is what will make a difference in the long run. This will let Jabber be the central clearinghouse for a variety of third-party services, including synchronization between database servers and handheld devices.

Jabber might be just an interesting product rather than part of a trend if it were unique. Instead, a host of products are frequently showing up with accompanying hardware. Lantronix and LiveDevices are just two companies in this space, and they are only the tip of the iceberg. Both of them have associated hardware on the client side.

Unfortunately, standards aren't as pervasive as the companies supporting them. Middleware is usually specific to a company, although Jabber.com's open-source approach tends to generate a de facto standard.

Internet-based solutions enlarge the number of devices connected to a server, and they can expand the number and kinds of developers creating applications for these environments. Embedded Linux is gaining ground against all embedded OSs, with Embedded Linux development tools showing major improvements. One example is the latest version of Lineo's Embedix SDK.

Additionally, Internet-based solutions are extending the realm of developers targeting these systems. More application developers are working on embedded projects as many companies make this transition easier. For example, Microsoft's Visual Studio, one of the most popular application development environments, is getting some surprising third-party, cross-platform support for non-Windows OSs. This lets new embedded developers use a familiar environment, in this case, Visual Studio. Accelerated Technology Inc. and LynuxWorks are two companies with products in this field.

Security is a major concern for Jabber.com (see "Encryption, Security Becoming Critical In Embedded Devices," below). Communication is authenticated, and local password databases are encrypted. Security with more sophistication is in the works for later in 2001.

Adding network support to devices can be a complex task, especially with compact, low-cost implementations. Lantronix's new Device Server Technology network interface (DSTni, pronounced "destiny"), provides Jabber and other real-time communication services. But clients are typically embedded devices that can take advantage of the DSTni chip or software for collaboration with either a local server or other DSTni-equipped devices (Fig. 2).

The hardware is an x186-based system-on-a-chip (SoC), complete with an Ethernet physical-layer interface (PHY) and support for a second external network connection. The primary Ethernet connection simply needs a driver chip and a connector. DSTni's integration is key to quickly developing networked products.

The DSTni chip isn't restricted to Ethernet connections. I²C, serial, and USB connections provide access to peripherals, while the CANBUS interface supplies a gateway to controller area network (CAN) devices often used in process-control and automotive arenas.

The DSTni chip runs the SuperTask! real-time operating system (RTOS) from U.S. Software, a Lantronics subsidiary. The chip's SDK includes a TCP/IP stack and Web server. Although its NetPeer support is proprietary, it's built on TCP/IP. The recent acquisition of Premise Systems will add more middleware support to DSTni. The initial version works with Ethernet, but future versions may employ other hardware transport systems, such as an 802.11b or a Bluetooth wireless connection.

LiveDevices has partnered with Microchip Technology and others to deliver the embedded hardware while it provides the software and a server farm designed to handle 100 million clients. The Internet connects the embedded devices and server farm (Fig. 3).

LiveDevices' support will be embedded in vending machines, among other devices. An embedded device will use the server farm for services, including file storage and authentication. Customer Web sites can supply a browser-based front end to users, and server-based applications can control or query the server farm. Customers will be provided with rented space and services on the server farm. A typical application would be a vending-machine company with intelligent vending machines that update sales automatically, allowing managers to query their status through the company's Web site.

Initially, the thrust for this architecture is the connection of remote devices to the server farm. In the future, though, other devices might offer coordinated services to the embedded devices. For instance, a set-top box home gateway could store time-shifted audio or video.

Security also is a major concern for the architecture. For this reason, encryption key management and distribution are part of the server farm support and the LiveDevices communication protocol. As with Lantronix, TCP/IP is the standards-based transport protocol. But the higher-level communication uses proprietary protocols.

TCP/IP is supported by Lineo's Embedix RealTime RTOS, which is part of the new Lineo SDK 2.0. In addition, remote debugging is supported over TCP/IP, but the central component of the new SDK is the Target Wizard.

The Target Wizard architecture has been changed to accept snap-ins that employ Embedded Component Description (ECD) files defining add-on services. The ECD architecture is used for Lineo's bundled components, such as Embedix RealTime, in addition to providing board and processor-specific support. This approach can work with third parties, allowing Lineo to support six new processor families beyond the original x86 and PowerPC platforms with this release of the SDK.

The ECD approach grants significant advantages to third-party developers as well as board and processor vendors. Support for product-specific peripherals and drivers can be added with an ECD file and matching libraries without working through Lineo.

Development platform support has been expanded from Caldera's OpenLinux to current releases of all major Linux distributions. Plus, the SDK can be installed and run under Windows 2000 using virtual-machine (VM) support to run OpenLinux. The installation process has improved greatly—a much needed enhancement.

A compact version of the SDK, Lineo's new Board Development Kit (BDK) works off of the same project files but is designed to work only with command-line, open-source tools. The BDK provides a low-cost entry point for embedded Linux development, and the cost can be applied toward the SDK.

Embedded Systems Conference attendees will be able to see how some tool vendors take linking different products together a step further. LynuxWorks' Visual LynuxWorks or Accelerated Technology's Codelab augment Microsoft's popular Visual Studio development environment for non-Windows-based, cross-platform development. Both can use Visual Studio's plug-in architecture to provide a front end for cross-platform development tools while taking advantage of other Visual Studio plug-in support for products like Source Safe, Microsoft's source management tool.

Visual LynuxWorks targets Linux systems, especially LynuxWorks' Lynx OS and its open-source sibling, Blue Cat Linux. Visual LynuxWorks was released earlier in January at LinuxWorld in New York City.

Now in its second incarnation, Accelerated Technology's (ATI's) Codelab provides a more modular approach to cross development with a plug-in architecture for board and processor support. This is similar in concept to Lineo's ECD architecture. The Codelab EDE (Embedded Development Environment) includes a number of wizards to handle the configuration of ATI's debugger or the open-source GNU development tools, among other tasks.

A source-level debugger, Codelab Debug supports the SH, MIPS, and ARC processor families. It can work in conjunction with CodeLab Partner, a JTAG interface. The Partner accepts probes for different system boards and processors, so the same platform can be used to debug different systems by simply changing the probe. ATI also has developed an ATX motherboard that accepts a daughter card with the target processor and memory. The daughter card works with Codelab Partner. Daughter cards for the SH4, NEC VR4122, ARM6, ARM7, and ARM9 are available.

Now for something completely different. The Embedded Systems Conference marks the debugging of Proceler's C-based soft processor core design capability. Proceler's Dynamically Variable Instruction Set Architecture (DVAITA) technology scans C/C++-defined algorithmic designs. It identifies computationally intensive code blocks like loops and breaks out this code or implementation in reconfigurable logic. DVAITA may turn a design into one or more soft processors. The remaining code is compiled for a standard microprocessor that's implemented as part of the solution. DVAITA targets configurable SoCs that combine a standard processor core with a reconfigurable system, such as an FPGA.