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USB: The Unsung Hero
The widespread use of USB ports has eliminated the guesswork in connecting accessories to your computer.
FROM: MAY-JUN 2005 ISSUE | BY G. WYNNE POWELL
Universal Serial Bus (USB) is the instant-connect interface, plug-and-play system that has made it easy for anyone to add accessories, such as a keyboard and mouse, printers, and scanners to a computer, opening the door to a myriad of features and connectivity.
USB was introduced in 1996 and has matured into a proven system. No longer must you struggle with multiple connectivity issues such as opening up your computer or configuring special drivers so that your operating system will recognize a new accessory. USB is extremely easy to use in both Windows XP and Mac environments.
USB is supported by a non-profit corporation founded by the group of companies that initially promoted the USB concept. Information about this group and standards is available at www.usb.org.
Since most computers and accessories today are USB-compliant, connectivity can be automated. Operating systems, such as Windows XP or Apple OSX, even offer "hot swapping," which allows you to add or disconnect USB items while the computer is running. Essentially, you just plug in the item and the operating system recognizes it and acts appropriately.
Two versions of USB currently exist. USB 1 provides reasonably fast transfer rates, but USB 2 can be up to 40 times faster. Most products manufactured today feature USB 2. High-speed USB 2 products have a design rate of 480MB per second. By comparison, the older standard parallel interface, used primarily for printers, transfers data at a mere 0.115MB per second. USB 2 offers an alternative to the IEEE-1394 bus system, known commercially as FireWire, used in high-quality consumer and professional video stream applications.
Devices available for USB are extensive and offer imaginative solutions for various personal computing needs. USB mass storage devices allow you to install additional storage without opening up your computer or installing any drivers. Key drives — known by a variety of names such as pen, flash, and memory keys — are examples of typical USB mass-storage devices. Some key drives offer a useful data encryption feature that prevents confidential data from being accessed by an unauthorized user. A multitude of storage sizes exist, with 512MB and 1GB sizes growing in popularity.
These convenient devices use flash memory. With only the USB connector protruding from the key drive and the small printed circuit encased in plastic casings, these devices are very resistant to physical damage. Key drives activate automatically when you plug them into current Windows operating systems. A light-emitting diode indicates that the device is connected and recognized by your computer. As in all flash memory devices, the write operation will gradually slow as the device ages. While it takes some time for this slowdown to occur, anyone relying on USB drives for actual software or operating systems should be aware of this limitation. Flash memory devices typically fail after experiencing several million cycles.
A number of manufacturers offer portable USB hard drives with performance that often equals or exceeds Integrated Drive Electronics (IDE), the standard interface used between the motherboard and hard drive. Seagate offers a 5GB USB hard drive, based on its one-inch format hard drive, which is no larger than a yo-yo. For a novel and convenient way to obtain storage portability, consider a 32MB storage watch from PowerFlash (www.youcansave.com). Other portable USB data storage devices, like Apple's iPod, will store and play your MP3 music files while serving as a portable filing system (www.apple.com/ipodphoto).
A variety of mice exist for USB connectivity. The designs vary, including very small optical mini-mice such as the Macally OptiMicro, featuring a USB port and portability, to augment standard mouse designs.
USB supports standard plug-and-play keyboards as well as an extensive variety of wireless keyboards, such as the Microsoft and Logitech cordless series. USB has not completely replaced the PS2 keyboard connections but many USB keyboard devices are shipped with a small USB to PS2 adapter.
Gaming devices like the ShockII programmable controllers are also available in USB format, demonstrating that USB can be the right choice for high-end gamer needs. Multimedia remote controllers, such as the Macally Keypoint Presentation device with a built-in laser pointer, will help you control presentations (www.macally.com).
The USB memory card reader is an efficient and easy way to read digital camera memory cards. Most readers can read up to eight different memory card formats and the transfer speed is typically considerably faster than plugging the camera cable into your computer.
The Photo iPod, apart from providing MP3 music and convenient and portable storage, also displays 25 full-colour thumbnails at one time for your picture-scrolling convenience.
Portable video Web cameras are also available for your USB port. The Creative Labs Web site at www.creative.com details a variety of choices. These cameras simply plug into your USB port, are easy to use, and are perfect for Web interview interactions with features like stunning 1024 × 768 pixel resolution.
In theory, you can connect up to 127 individual USB-compliant items at one time. As each item uses up some of the available USB bandwidth, the practical number is less than 127, but you can resolve this issue by adding more USB cards to your computer.
If your computer does not have enough USB ports for your needs, you can easily add a high-speed USB 2-compliant multi-port internal card that fits most personal computers. USB 2 adaptors also exist for notebook plug-in slots.
Many manufacturers provide special USB hubs that expand the number of USB ports. As you add peripherals to your USB highway, you should be aware that power is being provided for your accessories through the USB port. For most users, it is recommended that you standardize on power-supplied distribution hubs to ensure that your accessories have adequate power levels. You can purchase power-supplied hubs or just the simpler USB connectivity distribution hub systems. If you wish to avoid powered hubs, you need to check your USB items and see if they are high-power (above 100Ma) or low-power (below 100Ma) users. If the units are high power, you must use external powered units or an internal USB board that gets power from the computer.
You can even "daisy chain" multiple devices together to expand connectivity options. Since USB data flows both ways, there are many creative ways that USB connectivity can be used. Clever designs now permit you to mitigate short-run cable issues by adding a powered USB hub at the end of your first five metres, allowing a 10-metre maximum connectivity length. A word of caution: USB is not designed to be a major connectivity system between computers. If you need to connect just a few machines it will work well, but safety and other issues exist if you want to connect large numbers of computers together on a USB highway. Ethernet remains the best option for this type of connecting.
Older game, serial, PS2, and parallel port devices use different electronic signals than USB. Some manufacturers provide conversion units that permit you to use these devices with standard USB. USB to serial port adaptors, such as the Synchrotech products (www.synchrotech.com), allow you to connect your computer easily to any serial device. Synchrotech also offers a USB to parallel printer adaptor that supports most standard parallel printer devices.
If you want to increase the connectivity of your computer, chances are there is a USB device to meet that need. Additional USB devices are introduced frequently, making the USB port the unsung hero of connectivity.
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G. Wynne Powell, D.Tech. (Hon), FCGA, is President and COO of London Drugs Limited, a chain of drug stores in B.C., Alberta, Saskatchewan, and Manitoba, and President of TLD Computers Inc., which specializes in high-endPC networks and custom programming services. He also chaired the B.C. Institute of Technology from 1989 to 1995.