Jim,
A little education on USB seems in order:
developer.intel.com
Easy Plug and Play for Peripherals.
Universal Serial Bus allows virtually unlimited PC expansion "outside
the box." With USB, PC users no longer need to worry about
selecting the right serial port, installing expansion cards, or the
technical headaches of dip switches, jumpers, software drivers, IRQ
settings, DMA channels and I/O addresses.
USB features a "one-size-fits all" connector that makes it easy to
add and unplug peripheral devices, without ever opening the PC.
USB's "hot insertion and removal" feature makes expansion even
easier, because users can add peripherals without turning off their
PC. USB allows PCs (and PC users) to connect with an exciting
array of new digital imaging peripherals, integrated computer
telephony devices and multi-user games.
Universal Compatibility.
USB is an industry-wide Plug and Play specification that makes it
easy to expand PC functionality. USB is currently supported by over
400 leading companies, including PC manufacturers and suppliers of
telecommunications products, PC peripherals and software.
Simpler Peripheral Design.
By eliminating the need for add-in cards, USB makes peripherals
easier to design and manufacture. USB distributes power, so many
peripheral products no longer require separate power supplies.
Intel is supplying the PC industry with a family of validated USB
solutions, including advanced AGP chipsets and thoroughly validated
USB peripheral controller chips. Intel USB solutions are designed for
reliable Plug and Play performance-at both ends of the wire.
developer.intel.com
Universal Serial Bus technology now makes it easy for PC users to connect
monitors, printers, digital speakers, modems and input devices like graphics
tablets, scanners, digital cameras, joysticks and multimedia game
equipment. Here's a glimpse at the technical side of USB.
Two data rates
USB has two data rates, 12Mbps for devices requiring increased bandwidth,
and 1.5 Mbps for lower-speed devices like joysticks and game pads.
Tiered-star topology
USB uses a "tiered star topology" which means that some USB
devices--called USB "hubs"--can serve as connection ports for other
USB peripherals. Only one device needs to be plugged into the PC. Other
devices can then be plugged into the hub.
USB hubs
USB hubs may be embedded in such devices as monitors, printers and
keyboards. Stand-alone hubs could also be made available, providing a
handful of convenient USB ports, right on the desktop. Hubs feature an
upstream connection (pointed toward the PC) as well as multiple
downstream ports to allow the connection of additional peripheral devices.
Up to 127 USB devices can be connected together in this way.
Automatic configuration
USB host controllers (which are available as part of several Intel PCI chip
sets) manage and control the driver software and bandwidth (data flow)
required by each peripheral connected to the bus. Users don't need to do a
thing, because all the configuration steps happen automatically. The USB
host controller even allocates electrical power to the USB devices.
Like USB host controllers, USB hubs can detect attachments and
detachments of peripherals occurring downstream and supply appropriate
levels of power to downstream devices.
Electrical power
Another word about electrical power. Since power is distributed through
USB cables (with a maximum length of five meters), you no longer need a
clunky AC power supply box for many devices.
The bottom-line is that USB makes it easy to add peripherals to your PC,
and that can make your PC more productive and fun to use.
PS: Firewire is for storage devices, it's in the works.
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