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View Full Version : How many devices can the internal USB 2.0 interface support ?


cwojahn
12-12-2006, 09:18 PM
How many devices can the internal USB 2.0 interface support ?

Bear
12-12-2006, 09:47 PM
You can connect 127 devices to a USB port with the addition of USB hubs. Do you want us to do all of your homework for you? If you are studying for the A+ exam there are plenty of resources out there for reading and research.

USB. The USB (Universal Serial Bus) standard has made parallel, serial, and other ports look increasingly outdated. USB started appearing in PCs around 1996 and is now nearly ubiquitous. With a data transfer rate of 12Mbps for imaging and telephony devices and 1.5Mbps for low-speed peripherals such as joysticks and mice, the USB port offers a speedy connection along with the ability to connect up to 127 peripheral devices to a single port. USB uses Plug and Play and hot plugging, which lets a system automatically configure a new device as soon as it's plugged in, even if the PC is already running. The port is a thin slot on the front or rear of the system that features two metal points inside and a label showing a circle that has three arms coming straight out of it.

Even though you can attach multiple devices to the PC through USB, only one must be plugged into the USB port. Other peripherals are added through USB hubs, which might be integrated into the peripheral connected to the PC or packaged as a separate USB hub, which costs about $40. When you plug a device into a USB port, the system searches for and loads the required device driver, then checks periodically to see whether the peripheral is connected. If you detach the peripheral but reattach it later, the system recognizes it without reinstalling a driver.

The latest development in USBtechnology is USB 2.0, which has been called Hi-Speed USB becuase it has a bus speed of 480Mbps, which is 40 times faster than USB 1.1. This latest version of USBis expected to be available to consumers in the fall of 2001. Best of all, USB 2.0 is backward compatible with the original USB systems and peripherals.

Bear
12-12-2006, 09:53 PM
Spend the money and read the book. The book below worked for me and I aced both the software and hardware tests. There are plenty of study guides out there to choose from.

A+ Certification Guide (https://www.totalsem.com/cgi-bin/miva?Merchant2/merchant.mv+Screen=PROD&Store_Code=TS&Product_Code=1381619&Category_Code=AC)

cwojahn
12-12-2006, 10:08 PM
I have to get the book you recommended. Thanks. ;)

cwojahn
12-12-2006, 10:19 PM
I have recently started studying for A+ Certification, but before this I found this site to help resolve some major problems with a computer I inherited. This is a fantastic site that I am continue to learn from and I want to thank you all. :)

Bear
12-12-2006, 10:22 PM
I'm glad you enjoy the WS forums. As I said there are plenty of Computer Certification Resources (http://www.google.com/search?q=Computer+certification+forums&sourceid=ie7&rls=com.microsoft:en-US&ie=utf8&oe=utf8) out there.

Crash Override
12-13-2006, 07:45 AM
I have to get the book you recommended. Thanks. ;)
One thing I will add and I think Bear will agree, don't just read the books and become what is known as "Paper" certified. Do plenty of hands on. Break it and fix it over and over again until you can do it in your sleep. It does no good to know what to do if you can't actually perform the work. Best of luck to you in your studies and the exams. There are plenty here with expertise in many different areas so just ask if you have questions.

Jimmy Carter
12-13-2006, 10:05 AM
My advice is to take the new test coming out soon if not already out.

A lot of stuff has been eliminated. :)


PS: You can daisy chain 127 different devices using the USB drive. :D

Don't know how your power will hold up but it is true. :D