Univ Serial Bus Controllers

[Guest]

Please Who knows the difference Device: VIA Rev 5 or later USB Universal Host
Controller and USB Root Hud. In Device Manager under Class Universal Serial
Bus controllers I see two of them exactly. If I disconect the printer (it is
working OK) and plug in the USB cable to connect my Cell Phone Sony Ericsson
T616 with my PC, the Phone Monitor shows "Not Connected" I have all
softaware/drivers installed. Pls. Your help is appreciated.
Windows XP Home SP2

 

[R. McCarty]

A Host Controller is the "Parent" device for Root Hubs. Most
Hubs have two ports (or Channels) that equate to the sockets
on the motherboard back plane or front panel.
You may have a "Phantom" instance in the USB category that
is preventing your phone from connecting. You should also
check that your Device Manager listing has no "Unknown Devices"
This would be where a USB device is enumerated (Detected) but
it's unique VID has no matching .INF driver file to load.
Click View & tic/Check the option "Show Hidden Devices" in
Device Manager.

Post back if you require more help.

 

[Guest]

R.McCarty, Thanks......
I did check Device Manager and don't see "unkown devices", What "Phantom"
means? How can verify it I have "Phantom instance in the USB category"
Also if I connect the phone to my Son PC (Windows XP without SP2) it works ok.

 

[R. McCarty]

A Phantom Device can really be one of two things. Windows XP
remembers all physical devices that have ever been connected to
it. They appear in Device Manager categories slightly "Grayed Out"
or diminished in color from other devices in that same category.
Some aren't truly phantoms but perhaps devices that aren't currently
powered on. (Like a scanner or camera or printer).
In the case of USB devices there is a problem where a device is
plugged into socket #1. You unplug the device and subsequently
plug it into socket #3. Because XP remembers devices in it's table
it doesn't recognize it's the same device and re-enumerates it again.
In this case you can end up with Device XXXX & Device XXXX #2.
This is a true phantom, because in reality you only have one of those
devices. This is where enabling "Show Hidden Devices" comes into
play. Those phantoms will not appear in the normal Device Manager
display. In the case I described above you would want to remove or
unplug the device and remove all instances of it from it's category.
Then plug it back in and let XP enumerate it and load the drivers.
On my own system, I have my USB plugs labeled so I can plug
them back in their correct sockets to avoid the multiple instance
issues. USB hubs also have a fixed Bandwidth, so you have to be
careful about loading, especially with Composite USB devices like
Sound Cards.

 

[Not Me]

If your phone is like most USB [and Firewire] devices, Windows will
not"see" it unless it is switched on. Is it?
Gene K