USB, Universal Serial Bus:
An external bus supporting Plug and Play installation. USB
1.1 vs. 2.0 - USB = External Connectivity
Simplicity. Originally planned as a low speed peripheral device
bus, USB 2 will now compete with 1394 FireWire for
PC & Consumer Electronics Device Connectivity. A quick comparison of Transfer
Rates may help to explain this issue or see USB.org
According to www.formfactors.org,
Front Panel I/O: "The USB 2.0 connector is the same as USB 1.1
connector. The USB 2.0 specification defines a new high-speed transfer
rate of 480 Mb/sec., a 40x increase from the 1.1 specification."
1.1 = A maximum bandwidth of 12 Mbits / sec (equivalent to 1.5
Mbytes / sec), and up to 127 devices can be attached.
2 = A dramatic throughput increase to 480 Mbits/sec, challenging
(IEEE 1394) as the external serial interface of the future.
Fully Supported by Win98.
Win2000 & WinXP flavors.
To utilize USB 1.1, PCs have to meet the requirements of
Win98 or above.
Identifying USB versions - Windows
Device Manager and USB - UHC (1.1) Universal Host Controller vs.
EHC (2.0) Enhanced Host Controller. Otherwise, plug a USB 2.0
Device into the USB Port and WinXP Pro will identify connected Device &
And to capitalize on the speed of USB 2, we'll have to have the
following according to Microsoft: Win2000 or
flavors of WinXP.
The crucial aspect of previous USB Device implementation &
utilization, "Microsoft requires the host silicon expose a
self-powered USB 2.0 hub (with a Transaction Translator) hanging
downstream of every port of the USB 2.0 controller." This
should solve some of our USB 1.1 connectivity problems as well. Chalk it
up to Early Technology Exposure if you feel burned lately when your USB
Ports & Devices gave the graceful BSOD! Enjoy! GB
How to tell USB Differences from Windows Device Manager - USB
versions 1.1 & 2.0: UHC (Universal Host Controller) vs. EHC
(Enhanced Host Controller) respectively.
Technologies - See: White papers & Documents, Bios
Boot Spec & USB Specifications
- General USB Troubleshooting in Windows XP
"There are two types of USB cables, high speed and low
speed. Low-speed cables differ from high-speed cables primarily in
their shielding. If you plug a high-speed device into a low-speed
cable, you can cause signal distortion over long distances.
Verify the entire USB chain is working correctly to be certain that a
device that requires the ability to draw power from the hub is not
plugged into the chain on the other side of a non-powered hub. This
causes that hub and all of the devices down the chain to be suspended.
If the hub is a powered hub, verify that the power supply for that hub
is configured properly."
Out-of-Date Firmware or BIOS
"The key to all USB devices is the firmware. The USB
device's firmware contains all of the information about the device. A
port is not reset until all of the descriptors in the firmware have
been loaded and verified by the root hub. This is critical because it
applies to items such as printers and modems. Make certain that you
have the most up-to-date firmware that is available for both your
computer's BIOS and each individual device.
The symptoms of malfunctioning or incorrectly configured firmware
might be unusual. Typically, when you remove and then re-add a USB
device, the device simply becomes available again. However, the device
may be displayed as a second instance of that device, and load itself
as such in Device Manager. If you see duplicates of a device, verify
that you have the most up-to-date firmware for that device. This issue
is common with USB printers and modems. A similar issue that has the
same cause occurs when a device loads a device driver, and then adds a
second device for which there seems to be no driver. The second device
is displayed with an exclamation point in a yellow circle in Device
Manager. The device may work correctly, but you cannot remove the
"ghost" device until you unplug the parent device that seems
to have generated the ghost device. Also, you may be able to resolve
this issue by updating the firmware or the device driver for that
IPL (Initial Program Load) USB Boot Devices:
Compatibility for USB Boot Devices: Updated link (10/22/2003).
for Booting Windows from USB Storage Devices: (10/22/2003).
Out Networks AnywhereUSB: Currently USB 1.1 over IP Remote I/O
- Universal Serial Bus:
- Universal Serial Bus - EHCI Specification:
USB, Universal Serial Bus - News:
- Linksys, Maxtor Team Up For NAS Device:
Connecting Storage to the Network ...
Linksys $99 NSL (Network Storage Link)
claims to work with any USB enabled HD (6/15/2004).
- www.Linksys.com - Network
Storage Link: Share you
External Hard Drive on the LAN!
- Maxtor &
Linksys Establish Strategic Alliance Promoting Easy Home Network Storage:
Linksys NSLU2 - Network Storage Link for USB 2.0 Disk Drives:
USB Server - "Easily connect USB devices to a PC via a wired or
wireless Ethernet-based LAN. The USB Server enables attached USB
devices to be used and shared by client PCs on a LAN. In addition to
printers, the USB Server supports other USB devices such as hard
drives, scanners and more." USB Server ships in late Q1 2004,
MSRP $129. Showcased @ 2004
International CES this week! (1/7/2004)
- 822603 - Availability of the Windows XP SP1 USB 1.1 and 2.0 Update:
"The Windows XP USB User Interface does not support more than 10
Host Controllers." (9/15/2003)
- Yes, there are USB drivers for DOS... (6/28/2003).
Industrial introduces USB 6-in-1
Memory Reader/Writer (2/3/2003).
See: Super Panel!
- Build It External USB 2.0 Hard Drive (1/16/2003).
Expands USB 2.0 Connections (12/2/2002).