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Christian InTech Articles - Computers
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Computer Phone (VoIP) Pathology is Preventable
Computer Phone (VoIP) Pathology is Preventable
By Dee Scrip © All rights reserved.
You are in the telescopic cross hairs of unprincipled hackers if you own a computer or communicate using one of the 90% of VoIP (computer phone) services...
Expansion Slots, Cards, and Bays: Choosing the right computer case
An expansion card in computing is a printed circuit board that can be inserted into an expansion slot of a computer motherboard to add additional functionality to a computer system.
One edge of the expansion card holds the contacts that fit...
Hetman Will Help You Conquer Your Files Quickly and Effectively
SoftAge announces the availability of Hetman version 1.0 Early Access Program, a powerful dual-panel file manager for the Windows 98/NT/ME/2000/XP platforms. Despite the predominant use of Windows Explorer, the demand for an advanced file manager...
Personal Digital Darkroom
Why a digital darkroom? First of all this is a misnomer. You actually don’t need a darkroom. All that you need to have is a space for a printer and if you’re still using film, a film scanner. You need not set aside a large chunk of your time in...
WHAT IS SPYWARE AND HOW DO I REMOVE IT FROM MY COMPUTER?
Spyware is a menace to any computer, but there are many free Spyware removal products online to help out. It sounds rather sinister, doesn't it? In a way, it really is. Spyware (another name for Malware or Adware, which is Internet-speak for...
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The Universal Serial Bus
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Permission is granted for the below article to forward,
reprint, distribute, use for ezine, newsletter, website,
offer as free bonus or part of a product for sale as long
as no changes are made and the byline, copyright, and the
resource box below is included.
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The Universal Serial Bus
By Stephen Bucaro
Ports are connectors provided on a computer to comunicate
with peripheral devices such as modems and printers. The
RS232 serial port introduced in 1969 could transfer data
at a speed of 20 Kbps (kilobytes per second). The parallel
port introduced in 1981 could transfer data at a speed of
150 Kbps. Later improvements increased the speed of the
parallel port to 4 Mbps (megabits per second). Serial ports
and parallel ports are frequently subject to resource
conflicts.
In 1996 the Universal Serial Bus (USB) was developed to
replace the serial and parallel ports. Today, the USB port
is used to connect scanners, digital cameras, and external
storage devices like CD-RW drives. USB 1.1 can transfer
data at a speed of 12 Mbps. USB 2.0, introduced in 2000,
can transfer data at a speed of 480 Mbps.
Besides much higher speed, a main feature of USB is that
you can plug and unplug devices without restarting the
computer. The controller will sense the device and
reconfigure. Installing a USB device is as simple as
plugging it into a USB port.
Another feature of USB is that a single controller can
support up to 127 devices simultaneously. A USB device can
provide a port for another device, allowing you to "daisy
chain" devices together, or you can use a stand alone hub.
USB uses a single IRQ, I/O address range, and DMA
controller to poll the devices for data.
The USB cable has four wires, two for communications, and
two that can provide up to 500 mA (milliamps) of power
to
the USB devices. This means devices that only need a small
amount of power don't need to have a separate power supply
and power cord.
As you can see from the above specifications, USB 2.0 is
40 times faster than USB 1.1. But most operating systems
do not yet have native support for USB 2.0. Microsoft has
released USB 2.0 drivers for Windows XP. You can download
them from the Windows Update site:
http://windowsupdate.microsoft.com.
You can plug a USB 2.0 device into a USB 1.1 port, but you
will only get the 12 Mbps transfer speed. Similarly, you
can plug a USB 1.1 device into a USB 2.0 port, but you will
only get the 12 Mbps transfer speed.
If your computer was built in 1997 or later, you probably
have USB 1.1 support. The USB Implementers Forum provides
a free utility download that examines your hardware to
determine its USB capability. You can download it from:
http://www.usb.org/data/usbready.exe
If you have a computer with USB 1.1 support, you can use an
expansion card that provides USB 2.0.
Manufacturers of USB 2.0 devices provide drivers that work
with Windows 98 or higher. First you insert a CD that
comes with the product to install the driver. Then, when you
plug in the USB cable, the port will automatically
configure for the device.
The USB standard requires cables to operate at a length of
up to five meters, but many hardware manufacturers
guarantee their products to work only with the much shorter
cable that they provide.
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Resource Box:
Copyright(C)2002 Bucaro TecHelp. To learn how to maintain
your computer and use it more effectively to design a Web
site and make money on the Web visit
http://bucarotechelp.com
To subscribe to Bucaro TecHelp Newsletter Send a blank
email to bucarotechelp-subscribe@topica.com
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About the Author
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