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Last Updated December 10, 2003

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USB 2.0

Full speed vs. High speed

Although USB 2.0 devices are capable of higher speeds than the USB 1.1, not all devices take advantage of this ability.  USB 1.1 devices transfer data at either 1.5Mbps (low speed) or 12 Mbps (full speed). USB 2.0 devices operate at both of these speeds, (for backwards compatibility) and if designated as "high speed" device, can transfer data at 480 Mbps if used with a USB 2.0 port.

However. simply because a device is designated as USB 2.0, it does NOT mean it is capable of operating at High Speed (480 Mbps). It simply means that it is compliant with Revision 2.0 of the USB specification. USB 2.0 devices rated at "full speed" operate at 12 Mbps and are not any faster than a similar USB 1.1 device.

If you need the fast data transfer speeds USB 2.0 can offer, look for devices that are specifically designate "High Speed", and for the special logo displayed below..









Universal Serial Bus (USB)

The Universal Serial Bus (USB) is a relatively new technology that is designed to resolve all of the issues related to connecting peripheral devices to a workstation. It eliminates the need to open computer case for installing cards needed for certain devices, and designed to meet Microsoft Plug and Play (PnP) specification. USB also allows 127 devices to run at the same time on the bus using only one interrupt, it has dual-speed data transfer, 1.5Mbps and 12Mbps, and can provide limited power, (maximum 500mA of current) to devices attached on the bus.
Where to Start...
allUSB Cable Guide
Explain the different cable types and provide some links to reputable online merchants who sell them.

Everything USB
A USB port connects more than computers and peripherals. It has the power to connect you with a new world of PC experiences. Everything USB

USB Basics
A excellent guide to USB, from

USB Explained
Find out how USB works, how it will benefit you and why it is quickly becoming the industry standard for adding devices to your system! Source:

From the creators of the Universal Serial Bus, at

Articles and other resources..

General USB Troubleshooting in Windows 2000
Microsoft Knowledge Base Article: 242062 This article describes general troubleshooting of Universal Serial Bus (USB) devices in Windows 2000. 

How to Determine Which USB Controller Is Installed
Microsoft Knowledge Base Article: 242860 - This article describes how to identify your USB Host controller to determine if it is supported by Windows 2000. 

HOW TO: Disable the Use of USB Storage Devices in Windows XP
Microsoft Knowledge Base Article: 823732 - This article discusses two methods that you can use to prevent users from connecting to a USB storage device on a Windows XP-based computer.

Microsoft's USB Page
Directory of whitepapers, and other developer resources.

The Basics About Universal Serial Bus (USB) Device Driver Development
Microsoft Knowledge Base Article With the growing popularity of the universal serial bus (USB), many hardware vendors must offer a USB interface for devices that currently support only serial or parallel interface. 

USB Hub Resource Center
Only have 2 USB ports on your workstation? Get a hub, and add up to 127 devices!

USB Plug and Play IDs and Selecting Device Drivers to Load
Describes how an operating system (OS) that supports the Microsoft© Windows Driver Model (WDM) selects USB device drivers to load, based upon the matches between device IDs bus drivers reads from descriptors on the USB devices and Hardware IDs and Compatible IDs in system INF files.

Known Issues
Application May Not Open Handle to Plug and Play Device Connected to a USB Hub
Microsoft Knowledge Base Article: 259711 - When you remove a Plug and Play Universal Serial Bus (USB) hub (a surprise removal) and an application does not close the handle to a device connected to the hub, the application may not open the handle to the device when you plug in the USB Hub

Application Does Not Receive Device Arrival Notification for Plug and Play USB Devices
Microsoft Knowledge Base Article: 253643 - When you remove Plug and Play Universal Serial Bus (USB) device (a surprise removal) and an application fails to close the handle to that device, the application does not receive a subsequent device arrival notification when you plug the device in again. 

A USB Device May Not Work on a Computer That Has Multiple Processors 
Microsoft Knowledge Base Article: 306788 - When you USB device under the following conditions, the USB device may stop responding and you may need to restart your computer: 

Computer Hangs If USB Composite Device Is Removed While Being Reset
Microsoft Knowledge Base Article: 278489 - Your computer may stop responding (hang) after you remove a Universal Serial Bus (USB) composite device.

Computer Remains in Standby Mode After Insertion of USB Device
Microsoft Knowledge Base Article: 228112 - When you connect a Universal Serial Bus (USB) device into your computer while it is in Standby mode, your computer remains in Standby mode. 

Deadlock in USB Stack While Resuming from Suspend
Microsoft Knowledge Base Article: 302450 - When you resume a system with a universal serial bus (USB) keyboard and a USB mouse by using the keyboard, the system may not resume. This problem may occur intermittently. The system appears to stop responding (hang) when this problem occurs. 

Error message: The Hub Doesn't Have Enough Power Available to Operate..
Microsoft Knowledge Base Article: 234312 - When you connect a new USB device to a USB hub that is connected to your computer, you may receive the following error message: The hub doesn't have enough power available to operate the <devicename> USB Device. Would you like assistance in solving this problem? If you click No, the device may not function properly. This issue can occur if the USB hub is supplying the power to your device  

Multifunction USB Device Cannot Transfer 4 KB or Larger Files 
Microsoft Knowledge Base Article: 283787 - When you try to transfer a file that is 4 kilobytes (KB) or larger to or from a multifunction (or composite) Universal Serial Bus (USB) device, you may receive the following error message: drive letter:\ is not accessible. The request could not be performed because of an I/O device error.  

More Than Five USB Hubs in a Chain Are Not Supported
Microsoft Knowledge Base Article: 226308 - If you have a properly enumerated Universal Serial Bus (USB) hub connected to your Windows 2000-based computer and you add five more hubs connected in a chain, the last hub may not work properly. Windows 2000 does not support USB hubs more hubs more than five deep.
Five hubs deep is the limitation in the USB specification. It is not a limitation in Windows 2000.

"Stop 0x00000050" Error Message When USB Device Is Connected 
Microsoft Knowledge Base Article: 291284 - If you connect a Universal Serial Bus (USB - device to the USB port, your computer may stop responding (hang - with the following error message:

STOP 0x1E in Usbhub.sys with Surprise Removal of Plug and Play USB Hub
Microsoft Knowledge Base Article: 260830 - When you unplug a Plug and Play Universal Serial Bus (USB) hub (a surprise removal) several times, the following error message may be displayed: 

STOP 0x50 in Usbhub.sys with Surprise Removal of Plug and Play USB Hub
Microsoft Knowledge Base Article: 261199 - When you unplug a Plug and Play Universal Serial Bus (USB) hub (a surprise removal) several times, the following error message may be displayed: 

Unplug or Eject Hardware Icon Appears When Installing USB Device
Microsoft Knowledge Base Article: 227855 - The Unplug or Eject Hardware icon may appear on the right side of the taskbar when you install a Universal Serial Bus (USB) device.

Unsupported Via VT83C572/VT82C586 PCI-to-USB Chip Sets
Microsoft Knowledge Base Article: 233163 - Specific Via Universal Serial Bus (USB) controller chip sets are not supported in Windows 2000. 

USB Devices Missing in Device Manager After Computer Resumes from Hibernation
Microsoft Knowledge Base Article: 261643 - After a computer resumes from hibernation, Universal Serial Bus (USB) devices may be missing. Device Manager may no longer list the connected USB devices.

USB Devices Stop Working After Resuming from Standby 
Microsoft Knowledge Base Article: 305933 - When your computer resumes from standby, Universal Serial Bus (USB - devices on all ports may not be properly detected and re-enumerated. Additionally, if you exchange one device for another while your computer is on standby, the new device may not work properly after your computer resumes.

USB Speakers Make a "Pop" Sound When You Play Audio 
Microsoft Knowledge Base Article: 307271 - When you are listening to audio over Universal Serial Bus (USB) speakers, you may hear a pop. This may occur from every few seconds to every few minutes. 

USB WritePort Does Not Set dwDataCompleted to 0 When Allocating New Buffer If Data Size Is Variable
Microsoft Knowledge Base Article: 272493 - When you attempt to print to some Hewlett-Packard Universal Serial Bus (USB - printers, some of the data sent to the printer may be lost. 

Windows 2000 May Hang with USB Devices on Older Via Chip Set 
Microsoft Knowledge Base Article: 246755 - When you are using certain Universal Serial Bus (USB) devices on a motherboard with the Via chip set in Windows 2000, you may experience any of the following symptoms:

WHQL USB Floppy Test Tool May Not Finish
Microsoft Knowledge Base Article: 279634 - Hardware vendors may not be able to complete the Windows Hardware Quality Labs (WHQL) test for a USB floppy drive. Although the test may start, it may not finish.

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