February 25, 2008

The PC's Exoskeletons

By Max Baron

Today, more computing and storage is going on outside the PC than inside its enclosure. Originally, the desktop computer replaced office equipment such as the typewriter, the paper spreadsheet, the overhead projector, and the file cabinet. Programs became longer and more versatile, operating on data small enough to be stored and processed locally. Advances in processor and graphics performance gave rise to computer games whose code and data followed the same pattern. Eager to play games, the consumer became an important source of PC revenue, more so than the corporation.

Following large increases in general-purpose processor and memory performance and multimedia extensions, PC vendors targeted data-intensive workloads, but the desktop didnıt do so well. The PC needed exoskeletons. An exoskeleton can be a tool or prosthesis designed to assist, protect, and increase the power of the wearer. Medical texts associate exoskeletons with functions such as power and mobility assistance for people. The PCıs weakness is caused by embedded systems overlapping desktop applications and by vendorsı business strategies. Initially, the processor in a desktop and other general-purpose processors (GPP) were not designed to take on the digital-signal processing required for applications such as still imaging, music, and video. The GPP was never meant to sense and process analog data like temperature or acceleration or detect the presence of chemicals.

Some general-purpose processors have added the necessary instructions for digital-signal processing but not the architecture and the speed they needed to access memory executing short instruction loops on large nonresident data. Plugged into the motherboard of a PC, special-purpose circuits and software drivers could help. Bus-width speedups notwithstanding, this option is no longer available today, because recent PC systems leave just one or no open motherboard sockets.

Manufacturer greed integrates as much processing, graphics, and peripherals as possible—to raise the price of the system. Most of the time, PC manufacturers are not using the system software and hardware you would use if the choice were yours. If you buy this type of PC, you are stuck with a $1,000 quad-processor-powered system housed in a shiny impressive black enclosure running a slow operating system. You will have to throw away thousands of dollars of application programs and visual compilers that are no longer compatible with the operating system or vice-versa. If you are lucky, you may be able to toss the low-quality graphics board inserted by the OEM and insert a good one. But if you try to further improve the PC, you see there are no open sockets, and you find by calling support in Malaysia that there are no software drivers except those you have on the system. You are on your own. It feels like you bought a Mac with unpredictable features. There are, however, ways to prop up this PC using its high-speed interfaces.

Bandwidth permitting, you can add peripherals and computing power externally, because the PC provides high-speed Ethernet, USB, and IEEE 1394. Was that Appleıs reason for introducing FireWire followed by the speeded-up FireWire 800 version? FireWire 800 will be updated by FireWire S3200 per announcement made by the 1394 Trade Association. USB 3.0, expected to show up in some systems by mid-2008, will provide ten times the bandwidth of USB 2.0, enabling communication at an estimated 5.0Gb/s. Ethernet, not to be left behind, is already showing bandwidths on the order of 10Gb/s per color channel, using Wavelength Division Multiplexing (WDM) in fiber optics (see www.Internet2.org). Last, but not least, with the deployment of 4G, cellular connectivity will reach 1Gb/s.

The PCıs exoskeletons will have ample bandwidth to interface with the PC. They include processor-based peripherals, external storage, Internet-based computing, and portable computing. They will impact positively on the PCıs future, but embedded systems will have their own say.

If we set aside for a moment PC use in the office and focus on consumer applications, we find the desktop used as an enabler of Internet connectivity; a collector and transcoder of music, images and video; a means to reach the printer; and, very important, the only means to reach the display of data and multimedia.

Competing among themselves, designers of embedded devices are weakening the role of the PC in the home and preventing it from entering the living room. Take for example Internet browsing and Internet-based (remote) computing. Several manufacturers have already offered non-PC, non-Windows, sub-$150 systems that can browse the Internet. Owners donıt have to buy software. They can use MSOffice programs running remotely on a server and/or use remote storage for their data (see MPR January 29, 2007 ³CES: Unicoiıs Simple System,² and www.openpeak.com).

Another example can be found in digital still cameras. Connected to USB, a digital single-lens reflex (DSLR) can identify and make tradeoffs to focus on peopleıs faces, optimize for exposure and histogram, and take up to three 12Mpixel images per second and compress and store them faster than a PC. Moreover, cameras can correct images for red-eye, crop and straighten photos, and print them using PictBridge, an industry standard that allows cameras to send images directly to printers. Most of these printers can display the image thatıs about to be printed. Some cameras provide a High Definition Multimedia Interface (HDMI) for people that need to see the image on a big screen—the one they have in the living-room.

Embedded devices have long offered direct storage of multimedia into portable or fixed external hard drives or flash memory. Also available are self-contained transcoding units that can be used to convert music and video to some of the standards used by portable players and game systems that can support multimedia (see www.skymall.com). The cellphone could offer an integration of all these technologies that no longer require a PC. But it and other portable systems were missing the one differentiator that the PC still had: a large color display.

At CES 2008, Microvision and Texas Instruments showed the first cellphone-size color video projectors, taking away from the PC its last advantage in handling consumer multimedia. The cellphone and other wireless devices can become the tools of tomorrow, promoted from PC exoskeleton to autonomous computers.

Where does that leave the PC? It can become the manager of the multiple resources consumers will be using at home, but its job will be similar to the controller core in a SoC, where application-specific accelerators do most of the work. It will continue to be the principal resource in corporate and SOHO applications. Iım keeping my shiny-black quad-cored HP. But to enter the living room, the PC has to become an eye-pleasing supercomputer delivering applications that no other processor can do by itself.