Hello there!

A friend of mine has bought a new Laptop and tried to plug her USB 
Headset by Logitech into it. Skype and TeamSpeak don't recognize it, but 
when she puts it into the "right" USB Slot (she has two slots on the 
side of her laptop), it works.
Can anyone tell me why there's a difference which USB slot you pick? 
I've noticed that before on my PC and my Mac. On my PC, if I used a USB 
slot for my Headset or mouse I've already used, everything's dandy, if I 
put it into a new one, it wanted to recognize the hardware again. On my 
Mac, if I put a USB Harddrive into the wrong slot, it wouldn't find it, 
in the other one, it did.
*shrugs*

Any ideas? Is there a USB Hub Priority or some such idiotic "feature"?

I'm just curious, it's not that big trouble to just check a different 
USB slot, but I actually thought it was invented to just plug stuff in 
and have fun...

Regards,
Tim

-- 
aka "Tim Nikias"
Homepage: <http://www.nolights.de>

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> Any ideas? Is there a USB Hub Priority or some such idiotic "feature"?

IIRC with USB 1 on WinXP there were some "feature" whereby if you plugged 
the same device into a different socket Windows would think it was a new 
device and try to install it again (rather than assuming it was the same as 
the identical device plugged into a different socket 2 minutes ago).  If to 
install it you needed some special driver, then plugging it into a different 
socket would mean you needed to supply those drivers again.  (Just like if 
you open up your computer and plug some PCI card into a different slot, when 
you next boot Windows will want to install the drivers again as it thinks it 
is new hardware)

I thought this had been fixed with USB 2 and/or Vista, but maybe not if your 
friend is running a new laptop.

BTW a friend of mine had exactly the same problem with a card reader that 
needed specific drivers.

You can look in the device manager and see what goes on when you plug/unplug 
into different sockets.

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On Thu, 06 Mar 2008 14:43:13 +0100, Tim Nikias
<JUS### [at] gmxnetWARE> wrote:

>
>I'm just curious, it's not that big trouble to just check a different 
>USB slot, but I actually thought it was invented to just plug stuff in 
>and have fun...

Hmm! At my last job I had my graphics tablet installed on my works laptop from
my own disc. The laptop would only recognise the tablet if it was plugged into
the USB port it was in when it was installed. 

Regards
	Stephen

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And lo on Thu, 06 Mar 2008 13:43:13 -0000, Tim Nikias  
<JUS### [at] gmxnetWARE> did spake, saying:

> Can anyone tell me why there's a difference which USB slot you pick?

Just to second Scott's assessment I've noticed it can depend on what host  
controller is being used. I know on one of the XP computers I have the  
front two sockets are on a different host then the rear four and things  
plugged in the front need to be "found" again when plugged into the back  
and vice-versa.

-- 
Phil Cook

--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com

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You could try to enable, 'Legacy USB Support' on the Setup of the 
Motherboard if the USB product is old, or maybe is new and uses version 
2.0 USB specification while you're trying to plug it into a USB 1.1/1.0.

I hope this brigs you some light, good luck.

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Tim Nikias wrote:
> Any ideas? Is there a USB Hub Priority or some such idiotic "feature"?

No. The problem is that each USB device is supposed to have a unique 
serial number, so the OS knows when you plug the same device into a 
different port. On a sufficiently cheap piece of USB hardware (espcially 
those where it doesn't matter, like a mouse), they don't manufacture the 
bits that are different for each item.

Hence, when you plug the same device into the same port, Windows says "I 
saw that before, but it doesn't have a serial number, so I'll assume 
it's the same thing." When you plug it into a different port, Windows 
assumes it's a different device, and goes through the install dance again.

Same thing happens if you wipe out the serial number on the drive inside 
a USB disk enclosure - Windows doesn't know it's the same disk, and 
reinstalls it.

(Reading the USB specs, and how you're supposed to handle such things, 
is actually the correct way of figuring this out, rather than guessing. ;-)

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."

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Darren New <dne### [at] sanrrcom> wrote:
> No. The problem is that each USB device is supposed to have a unique 
> serial number, so the OS knows when you plug the same device into a 
> different port. On a sufficiently cheap piece of USB hardware (espcially 
> those where it doesn't matter, like a mouse), they don't manufacture the 
> bits that are different for each item.

> Hence, when you plug the same device into the same port, Windows says "I 
> saw that before, but it doesn't have a serial number, so I'll assume 
> it's the same thing." When you plug it into a different port, Windows 
> assumes it's a different device, and goes through the install dance again.

  What I don't understand is why Windows can't do "hmm, I *already* have
the driver for this device installed, I don't need to install it again,
I'll just support the device right away". It's not like connecting it to
a different usb port would make recognizing the type of device more difficult
than connecting it to the same port as yesterday.

-- 
                                                          - Warp

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Warp wrote:
>   What I don't understand is why Windows can't do "hmm, I *already* have
> the driver for this device installed, I don't need to install it again,
> I'll just support the device right away". It's not like connecting it to
> a different usb port would make recognizing the type of device more difficult
> than connecting it to the same port as yesterday.

It's not actually installing new code for the device. It's installing 
the configuration for that particular instance of that particular kind 
of device. It doesn't prompt you for a CD or anything. It just writes 
the configuration into the registry, starts up any services need to 
support it, and so on.

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."

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In article <47d1a82d@news.povray.org>, war### [at] tagpovrayorg says...
> Darren New <dne### [at] sanrrcom> wrote:
> > No. The problem is that each USB device is supposed to have a unique 
> > serial number, so the OS knows when you plug the same device into a 
> > different port. On a sufficiently cheap piece of USB hardware (espciall
y 
> > those where it doesn't matter, like a mouse), they don't manufacture th
e 
> > bits that are different for each item.
> 
> > Hence, when you plug the same device into the same port, Windows says "
I 
> > saw that before, but it doesn't have a serial number, so I'll assume 
> > it's the same thing." When you plug it into a different port, Windows
 
> > assumes it's a different device, and goes through the install dance aga
in.
> 
>   What I don't understand is why Windows can't do "hmm, I *already* have
> the driver for this device installed, I don't need to install it again,
> I'll just support the device right away". It's not like connecting it to
> a different usb port would make recognizing the type of device more diffi
cult
> than connecting it to the same port as yesterday.
> 
It will, for things like thumb drives. Why it won't for *other* things 
is beyond me, especially given that a significant number of items are 
now USB based... :(

-- 
void main () {
  If Schrödingers_cat is alive or version > 98 {
    if version = "Vista" {
      call slow_by_half();
      call DRM_everything();
    }
    call functional_code();
  }
  else
    call crash_windows();
}

<A HREF='http://www.daz3d.com/index.php?refid=16130551'>Get 3D Models,
 
3D Content, and 3D Software at DAZ3D!</A>

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Patrick Elliott <sel### [at] rraznet> wrote:
> It will, for things like thumb drives. Why it won't for *other* things 
> is beyond me, especially given that a significant number of items are 
> now USB based... :(

  So much for the much-touted plug&play... :P

  (With some devices plug&play works and is really nice. For example,
if you connect a simple game controller to an USB port, it just works.
Why can't all USB devices be like that?)

-- 
                                                          - Warp

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Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> No. The problem is that each USB device is supposed to have a unique 
>> serial number, so the OS knows when you plug the same device into a 
>> different port. On a sufficiently cheap piece of USB hardware (espcially 
>> those where it doesn't matter, like a mouse), they don't manufacture the 
>> bits that are different for each item.
> 
>> Hence, when you plug the same device into the same port, Windows says "I 
>> saw that before, but it doesn't have a serial number, so I'll assume 
>> it's the same thing." When you plug it into a different port, Windows 
>> assumes it's a different device, and goes through the install dance again.
> 
>   What I don't understand is why Windows can't do "hmm, I *already* have
> the driver for this device installed, I don't need to install it again,
> I'll just support the device right away". It's not like connecting it to
> a different usb port would make recognizing the type of device more difficult
> than connecting it to the same port as yesterday.

That's exactly what keeps me wondering as well. The Laptop (about 4 
months old, BTW) recognizes the USB Headset on one USB, but not on the 
other, AND it doesn't usually need any installation whatsoever, you just 
plug it in and it gets recognized as a pair of headphones and a mic.

I just don't get whats going on. Of course, always using the same USB 
slot solves the problem, but it IS kinda strange, given the actual idea 
behind USB, right?



-- 
aka "Tim Nikias"
Homepage: <http://www.nolights.de>

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Tim Nikias wrote:
> 
> I just don't get whats going on. Of course, always using the same USB 
> slot solves the problem, but it IS kinda strange, given the actual idea 
> behind USB, right?
> 

Doesn't solve, but works around usually. Think the possibility of having 
a memory stick with open files (wait, *gasp*, that's... POSSIBLE) on 
that very USB-connector, when in need to put in the headset.

-- 
Eero "Aero" Ahonen
    http://www.zbxt.net
       aer### [at] removethiszbxtnetinvalid

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Warp wrote:
> Why can't all USB devices be like that?)

They can. It just costs a few pennies more to put a distinct serial 
number on every device.

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."

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Tim Nikias wrote:
> I just don't get whats going on. Of course, always using the same USB 
> slot solves the problem, but it IS kinda strange, given the actual idea 
> behind USB, right?

And you're following up on a message where I explained what's going on, 
ya know...

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."

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>> It will, for things like thumb drives. Why it won't for *other* things
>> is beyond me, especially given that a significant number of items are
>> now USB based... :(
>
>  So much for the much-touted plug&play... :P
>
>  (With some devices plug&play works and is really nice. For example,
> if you connect a simple game controller to an USB port, it just works.
> Why can't all USB devices be like that?)

There are some USB standard protocols that are understood by the OS without 
the need for any drivers, like for keyboards, mice, game controllers, data 
storage etc.  Of course a manufacturer is not forced to use these standards, 
but if they don't they will need to provide some extra driver software 
(usually providing some extra functionality above the standard OS protocol).

Also what Darren said, for things like game controllers it is very expensive 
to add some unique serial number, as there is no other need to have any 
non-volatile information stored inside it (unlike a pen-drive or camera). 
To store a serial number you will need to add some extra chip and program 
it, or hard-code some bit-pattern circuitry inside the device - both 
extremely expensive compared to just assembling parts in exactly the same 
way.

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Darren New wrote:
> Tim Nikias wrote:
>> I just don't get whats going on. Of course, always using the same USB 
>> slot solves the problem, but it IS kinda strange, given the actual 
>> idea behind USB, right?
> 
> And you're following up on a message where I explained what's going on, 
> ya know...

Well, to my defense, I did say that the Headset doesn't actually require 
installing or has any disk for that matter. So no matter if there's a 
serial number or not, plug&play is what should be happening, not "plug 
in one slot and recognize it, plug it in the other and the system has no 
frickin clue what the USB device is".

If it would ask to reinstall some weird OS-given drivers that aren't 
installed with the basic OS, but are found on the OS' Install CD, I 
would have agreed, but since *nothing* is required when plugging it in, 
it DOES seem kinda strange that one USB recognizes the Headset and the 
other doesn't.

I've got the same headset. Plugging it into any of the 7 USB ports on my 
PC (Windows XP) or the two on my Mac (Leopard) doesn't make a 
difference, but it does on the two USB slots of my friend's laptop 
running Vista.

Regards,
Tim


-- 
aka "Tim Nikias"
Homepage: <http://www.nolights.de>

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Tim Nikias wrote:
> I've got the same headset. Plugging it into any of the 7 USB ports on my 
> PC (Windows XP) or the two on my Mac (Leopard) doesn't make a 
> difference, but it does on the two USB slots of my friend's laptop 
> running Vista.

That was my bad. I got confused between the game controller and the 
headset.  Yeah, it should recognise the headset in both USB slots, I'd 
think.

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."

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