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<h1><a href="sb_fact.htm"><img src="gif/susblogo.gif" border="0"
width="200" height="66"></a>USB Frequently Asked Questions</h1>
<p align="center"><a name="top"></a></p>
<ul>
<li>This site is a service of the USB Implementers Forum
staff. The primary charter for that staff is to support
the USB Implementers Forum member companies with
Developers Conferences, Spec Technical Support and
Compatability Workshops. We also provide marketing
exposure for our members as a unified group of companies
producing USB products, at trade shows such as Comdex and
PC Expo . <p>Our secondary charter is to provide the
industry at large with any information that is available
to foster understanding and development of USB. This FAQ
is a tool in that information distribution. </p>
<ol>
<li><a href="#usb">What is USB?</a> </li>
<li><a href="#periph">What kind of peripherals will
USB allow me to hook up to my PC?</a> </li>
<li><a href="#how">How does it work?</a> </li>
<li><a href="#soft">Will I need to purchase special
software to run USB peripherals?</a> </li>
<li><a href="#cost">Will USB peripherals cost more?</a>
</li>
<li><a href="#mac">Is there a Mac version of the
standard?</a> </li>
<li><a href="#products">Are there USB products out
right now?</a> </li>
<li><a href="#dongle">How can USB be used between 2
hosts, like a laptop and a desktop?</a></li>
<li><a href="#firew">How does USB compare with Sony's
FireWire/IEEE 1394 standard?</a> </li>
<li><a href="#avail">When it is available, will
FireWire replace USB?</a> </li>
<li><a href="#mag7">Who created USB anyway?</a> </li>
<li><a href="#recip">What are the Intellectual
Property issues with USB, is there a license,
what does it cost, what is the "Reciprocal
Covenent Agreement" I've heard about?</a></li>
<li><a href="#usbif">What is the USB-IF?</a> </li>
<li><a href="#bennies">What are the benefits of
USB-IF?</a> </li>
<li><a href="#membership">How do I Join USB-IF?</a> </li>
<li><a href="#contacts">How do I get in touch with
USB-IF?</a> </li>
<li><a href="#hcis">What about this OHCI and UHCI?</a>
</li>
<li><a href="#wspec">Where can I get a spec?</a> </li>
<li><a href="#newsgroup">Is there a newgroup for USB?</a>
</li>
<li><a href="#vendorid">How do I get a USB vendor ID?</a>
</li>
<li><a href="#emc">Where can we get EMC testing
peripherals?</a> </li>
<li><a href="#fireusb">Hasn't someone informed the
trade press that there is a need for Firewire and
USB?</a> </li>
<li><a href="#longusb">Is the USB bus going to have a
long distance 50-200 meter extension (possibly
fiber) for these large customers that need the
capability?</a> </li>
<li><a href="#legacy">Will legacy device suport be in
the formal USB spec? When?</a> </li>
<li><a href="#xhcicode">Will source code for driving
HCI chips be made available?</a> </li>
<li><a href="#autoattch">When a device is detached
it's device driver is unloaded, if that device is
re-inserted, would it's driver be reloaded?</a> </li>
<li><a href="#fastusb">Are there any plans to
increase the bus bandwidth of USB in the future
to 2x, 3x?</a> </li>
<li><a href="#abcon">Can someone clarify the
defference and applications for series
"A" and series "B"
connectors?</a> </li>
<li><a href="#rhub">What is the difference between a
root hub and normal hub in terms of hardware and
software?</a> </li>
<li><a href="#specdl">Where can I get a spec?</a> </li>
<li><a href="#massstor">Is USB a viable Bus for
peripherals like CD-R, tape or hard disk drives?</a>
</li>
<li><a href="#uhcipub">The programming spec for UHCI
is not publicly available. When can one get the
UHCI spec?</a> </li>
<li><a href="#pdk">How do I get a USB PDK system?</a>
</li>
</ol>
<p><a name="usb"></a> <br>
</p>
<ol>
<li>What is USB? <br>
<blockquote>
<p>USB is peripheral bus standard developed
by PC and telecom industry leaders -- Compaq,
DEC, IBM, Intel, Microsoft, NEC and Northern
Telecom -- that will bring plug and play of
computer peripherals outside the box,
eliminating the need install cards into
dedicated computer slots and reconfigure the
system. Personal computers equipped with USB
will allow computer peripherals to be
automatically configured as soon as they are
physically attached - without the need to
reboot or run setup. USB will also allow
multiple devices -- up to 127 -- to run
simultaneously on a computer, with
peripherals such as monitors and keyboards
acting as additional plug-in sites, or hubs. </p>
</blockquote>
<p><a name="periph"></a> <br>
</p>
</li>
<li>What kind of peripherals will USB allow me to
hook up to my PC? <br>
<blockquote>
<p>You name it: monitors controls, audio IO
devices, telephones, modems, keyboards, mice,
4x and 6x CD ROM drives, joysticks, tape and
floppy drives, imaging devices such as
scanners and printers. USB's 12 megabit/s
data rate will also accommodate a whole new
generation of peripherals, including MPEG-2
video-based products, data gloves and
digitizers. Also, since computer-telephony
integration is expected to be a big growth
area for PCs, USB will provide a low-cost
interface for Integrated Services Digital
Network (ISDN) and digital PBXs </p>
</blockquote>
<p><a name="how"></a> <br>
</p>
</li>
<li>How does it work? <br>
<blockquote>
<p>Drawing its intelligence from the host PC,
USB will detect when devices are added and
removed. The bus automatically determines
what host resource, including driver software
and bus bandwidth, each peripheral needs and
makes those resources available without user
intervention. Users with a USB-equipped PC
will be able to switch out compatible
peripherals as needed easily as they would
plug in a lamp. </p>
</blockquote>
<p><a name="soft"></a> <br>
</p>
</li>
<li>Will I need to purchase special software to run
USB peripherals? <br>
<blockquote>
<p>The Windows operat ing system(since OSR
2.1 release on October 29, 1996) comes
already equipped with the feature (called
"drivers") that allows your PC to
recognize USB peripherals. Ultimately, you
will not need to purchase or install
additional software for each new peripheral.
However, new peripheral products (including
those never-before-seen) may mean a gap
between the peripheral availability and
software upgrades. This may mean you receive
a diskette with your new USB peripheral with
the updated driver information. </p>
</blockquote>
<p><a name="cost"></a></p>
<p><br>
</p>
</li>
<li>Will USB peripherals cost more? <br>
<blockquote>
<p>USB peripherals will be competitively
priced with the peripherals available on the
market today. </p>
</blockquote>
<p><a name="mac"></a> <br>
</p>
</li>
<li>Is there a Mac version of the standard? <br>
<blockquote>
<p>Not currently.. </p>
</blockquote>
<p><a name="products"></a> <br>
</p>
</li>
<li>Are there USB products out right now? <br>
<blockquote>
<p>Yes. Almost all new PC designs from major
vendors shipping today have USB connections
on the motherboard and the correct Win OS to
make them work. There are also many products
used to design and build USB systems, such as
connectors, chipsets and board-level
computers. USB peripherals, including
keyboards, monitors, mice and joysticks, are
slowly starting to appear Q1 1997.</p>
</blockquote>
<p><a name="dongle"></a></p>
</li>
<li>How can USB be used between 2 hosts, like a
laptop and a desktop?<br>
<ol>
<li>The answer is a small adapter that would
appear as a device to each USB system
desiring connections. Two USB peripheral
microcontrollers sharing a buffer memory
would be a quick solution and could sell
for under $50. The packaging could be as
streamlined as a small blob(dongle) in
the middle of the cable or maybe even a
slightly large connector shell at one end
and nothing in the middle of the cable. A
cable like this could also perform hub
functions for very little extra cost to
produce a higher value product.</li>
</ol>
<p><a name="firew"></a></p>
</li>
<li>How does USB compare with Sony's FireWire/IEEE
1394 standard? <br>
<blockquote>
<p>They differ most in terms of application
focus, availability and price. The USB
feature is available now and will address
more traditional PC connections, like
keyboards, mice, joysticks and handheld
scanners. However, USB's data rate (12
Mb/s)is more than adequate for many consumer
applications including more-advanced computer
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