Internet Appliances with a Twist
The first information appliance Adomo will deliver is a sleek unit called the “Wing” (see Figure 2).
The Wing is a multi-function user-interface appliance that contains a 90MHz Motorola Coldfire system-on-chip processor and a VGA display controller, along with interfaces for infrared keyboard/mouse, PS/2 mouse, microphone and speakers. An internal PCMCIA socket provides the wireless LAN connection. The Wing has a small built-in speaker and microphone, and provides jacks for optional connection of external high-quality stereo speakers and microphone.
Since the Wing is simply a nice-looking but “dumb” terminal, it can be used for a variety of purposes. Hook it up to a monitor, keyboard and mouse, and it acts like a PC. Leave those off and connect it to high-quality stereo speakers, and it becomes a wireless music system that plays Internet radio, CDs and MP3s.
One of Adomo's strategies to make their products “family-friendly” is extensive use of voice for both commands and data. What could be more natural for family-oriented systems? Accordingly, family members will be able to leave each other voice messages as easily as e-mail messages, and in much the same way.
Despite recent progress, however, decent-quality voice recognition still requires desktop-level computing power. This limits the voice-recognition capabilities of low-cost information appliances. But in the Adomo client/server architecture, the devices need only send 10KBps voice data to the server. There, high-end CPU resources are available to process it. The result: low-power, inexpensive appliances benefit from high-end speech recognition technology.
Why did Adomo choose to use Linux? “On the client side, scalability, modularity and availability of source, which allowed us to customize the OS to meet our exact requirements, were key reasons for using Linux,” says Adomo CEO Samir Lehaff. “On the server side, Linux offered us a highly stable multi-user OS, without the usual licensing and serialization headaches associated with trying to use Windows NT in an embedded product.”
The Adomo application required customizing a Linux server OS to make it suitable for the home environment and developing a set of hosted applications for home users. The server is based on a Red Hat Linux distribution, along with the Netscape Mozilla open-source browser. The applications are aimed at communications, web browsing, data manipulation and organization, backup and household task management. One such application is an MP3 music jukebox. The client devices run a diskless X-terminal version of uCLinux ported to a Motorola Coldfire microprocessor. This provides an economical and versatile platform for a wide range of future devices.
Adomo's embedded Linux-based development project benefited greatly from collaboration with the Open Source community. For example, Adomo had to grow uCLinux from its normal headless “network box” configuration into a full-fledged X-terminal implementation, while still maintaining a small memory footprint. For assistance with that challenge, Adomo turned to embedded Linux specialists at Moreton Bay (now a Lineo company).
Similarly, SuSE provided some important help in implementing a truly embeddable X server for the client devices. This took the form of Tiny-X, a reduced-footprint implementation of the X Window System that requires less than 800KB of memory.
Another challenge was running Linux on client devices that don't contain application program-load memory, beyond a small ROM used for system bootstrap. Instead, the client devices boot Linux remotely via wireless LAN. Help in overcoming this problem came from the Linux Terminal Server Project (LTSP) team.
Will Adomo allow third-party developers or even users to modify how the system operates? “Absolutely!” says Adomo CEO Lehaff. He says the company will post its embedded Linux technology, as GPL, on its web site. The company will also encourage third-party developers to create both software applications and additional client devices.
Adomo plans to launch its products in October 2000, with production ramp-up in time for the 2000 holiday season. Lehaff describes the target market as “technology-friendly families who are faced with organizing and networking a growing number of Internet-connected devices in the home.” In addition to the server and the Wing, Adomo plans to introduce two additional products early next year: AdomoPad, a battery-operated wireless touch-screen pad that integrates web browsing and telephone functions, will be used like a jumbo PDA; and AdomoTune, a device that will allow digital music received from the server or the Internet to be played over high-quality audio equipment.
Rick Lehrbaum (firstname.lastname@example.org) created the http://www.LinuxDevices.com/ “embedded Linux portal”, which recently became part of the ZDNet Linux Resource Center. Rick has worked in the field of embedded systems since 1979. He co-founded Ampro Computers, founded the PC/104 Consortium, and was instrumental in launching the Embedded Linux Consortium.