USB cables: Difference between 1.1 and 2.0 ???

Curious....

I used an *old USB cable* to connect my laptop's USB 2 port to a USB 2
device.

I got a WinXP message (seemingly a little wrong) which claimed that I was
using a low speed USB port and that moving the cable to a high speed port
would result in higher rates.

Bunch of questions, given that I cannot find cable wiring differences
online.

1. Is there a difference between cables.

2. Did Windows XP get confused and respond to the slow cable as if it were
instead a slow port. This seems like a silly error message.

3. Possibly unrelated: There is a lumpy thing on the cable near the B side.
Reminds me of the ferrite core that I saw on my atari-800 video out cable.
(stop snickering). The usb cable loops through it once. What is it, and is
this related to shielding, emmissions, indirectly speed, or what?

Thanks guys

"Thomas G. Marshall" <. com>
wrote in message news:AeRci.242$p45.109@trndny01...
>
> Curious....
>
> I used an *old USB cable* to connect my laptop's USB 2 port to a USB 2
> device.
>
> I got a WinXP message (seemingly a little wrong) which claimed that I was
> using a low speed USB port and that moving the cable to a high speed port
> would result in higher rates.
>
> Bunch of questions, given that I cannot find cable wiring differences
> online.
>
> 1. Is there a difference between cables.

No. Any proper USB1 cable can be used for USB2. Since USB2 is pickier, it's
possible that a bad cable work work for USB1 and fail for USB2.

> 2. Did Windows XP get confused and respond to the slow cable as if it were
> instead a slow port. This seems like a silly error message.

This could happen if you had a bad cable, I assume. Do you get this message
when using other USB cables?

> 3. Possibly unrelated: There is a lumpy thing on the cable near the B
> side. Reminds me of the ferrite core that I saw on my atari-800 video out
> cable. (stop snickering). The usb cable loops through it once. What is
> it, and is this related to shielding, emmissions, indirectly speed, or
> what?

Just cuts down on RF leakage. Should not affect speeds, etc.

On Sat, 16 Jun 2007 13:05:36 GMT, "Thomas G. Marshall"
<. com>
wrote:

>
>Curious....
>
>I used an *old USB cable* to connect my laptop's USB 2 port to a USB 2
>device.
>
>I got a WinXP message (seemingly a little wrong) which claimed that I was
>using a low speed USB port and that moving the cable to a high speed port
>would result in higher rates.
>


Usually this means you don't have the proper USB2 driver
installed for USB so it's running in USB1 mode regardless of
the cable.

In comp.sys.ibm.pc.hardware.misc Thomas G. Marshall <. com> wrote:

> Curious....

> I used an *old USB cable* to connect my laptop's USB 2 port to a USB 2
> device.

> I got a WinXP message (seemingly a little wrong) which claimed that I was
> using a low speed USB port and that moving the cable to a high speed port
> would result in higher rates.

> Bunch of questions, given that I cannot find cable wiring differences
> online.

> 1. Is there a difference between cables.

Officially: no. Practically: sometimes. I have had some older USB cables
that produced interface errors with USB 2.0. Using an USB 2.0 cable
(or simply a new USB cable) removed the problem in each case. My
theory is that these were actually substandard USB cables and that
with USB 1.0/1.1 the difference was not large enough to cuase problems,
wile with USB 2.0 it was.

> 2. Did Windows XP get confused and respond to the slow cable as if it were
> instead a slow port. This seems like a silly error message.

No. It is not possible to detect a substandard USB cable in software.
The only thing you may get is more transmission errors. XP is pretty
backwards with USB support. Typically USB 1.0/1.1 work out of the
box, but USB 2.0 may require a driver.

> 3. Possibly unrelated: There is a lumpy thing on the cable near the B side.
> Reminds me of the ferrite core that I saw on my atari-800 video out cable.
> (stop snickering). The usb cable loops through it once. What is it, and is
> this related to shielding, emmissions, indirectly speed, or what?

It is an EMI (Electro Magnetic Intererence) ferrite. It basically
blocks very high frequencies that could cause problems with radio
equipment. Often these are not really needed, and their use is a bit
of black magic. For example in many circuit diagramms you will
find them listed as "ferrite bead" or "bead <size>" without
the electrical characteristics being given.

Arno

"Thomas G. Marshall" <. com>
wrote in message news:AeRci.242$p45.109@trndny01...
>
> Curious....
>
> I used an *old USB cable* to connect my laptop's USB 2 port to a USB 2
> device.
>
> I got a WinXP message (seemingly a little wrong) which claimed that I was
> using a low speed USB port and that moving the cable to a high speed port
> would result in higher rates.
>
> Bunch of questions, given that I cannot find cable wiring differences
> online.
>
> 1. Is there a difference between cables.
>

Yes - and No. Although any cable that operates at USB2* speeds will also
operate at USB1, the reverse is not necessarily true. Although the vast
majority of cables that were made when USB1 was all there was will operate
quite happily at USB2 speeds, there are some that won't. In particular some
USB1 cables were only designed to operate at the USB1 low speed and only had
simple twisted pair cables. These definitely won't work at USB2 speeds.

> 2. Did Windows XP get confused and respond to the slow cable as if it were
> instead a slow port. This seems like a silly error message.
>

Windows detected that the communication over your cable was unreliable at
480 Mbps and reverted to 12 Mbps operation. The error mesage is in response
to this (though you may not have guesed - software writers pride themselves
in error messages that don't actually tell you what is wrong).

> 3. Possibly unrelated: There is a lumpy thing on the cable near the B
> side. Reminds me of the ferrite core that I saw on my atari-800 video out
> cable. (stop snickering). The usb cable loops through it once. What is
> it, and is this related to shielding, emmissions, indirectly speed, or
> what?
>

It is a ferrite core that you may have seen on several other cables. It is
so that the cable and the item it connects to meets the European EMC
directive. You should only ever use a peripheral with the cable with which
it is supplied, otherwise you may be in breach of the EMC directive. Having
said that: who does?

*I use the term USB2 here to refer to USB communication at 480 Mbps. In
practice a USB2 peripheral need not actually be capable of operating at 480
Mbps - something to bear in mind when you buy anything claiming to be USB2
compliant (SONY video cameras particularly leap to mind!).

"kony" <> wrote in message
news:...
> On Sat, 16 Jun 2007 13:05:36 GMT, "Thomas G. Marshall"
> <. com>
> wrote:
>
>>
>>Curious....
>>
>>I used an *old USB cable* to connect my laptop's USB 2 port to a USB 2
>>device.
>>
>>I got a WinXP message (seemingly a little wrong) which claimed that I was
>>using a low speed USB port and that moving the cable to a high speed port
>>would result in higher rates.
>>
>
>
> Usually this means you don't have the proper USB2 driver
> installed for USB so it's running in USB1 mode regardless of
> the cable.

Whilst the message may convey this impression, it is a catch all for almost
any situation in which a Hi speed capable peripheral will not operate at
high speed. This includes (but is not restricted to).

*High speed peripheral connected to non high speed port (either on the PC or
a HUB) when such is present.

*High speed communication with peripheral is not reliable for any reason and
the host reverts to fast speed.

*The EHCI transmitter or receiver on the chosen port has failed.

*The USB lead is incorrectly terminated at either or both ends.

"M.I.5¾" <_SPAM.co.uk> writes:
> >
> > 1. Is there a difference between cables.
> >
>
> Yes - and No. Although any cable that operates at USB2* speeds will also
> operate at USB1, the reverse is not necessarily true. Although the vast
> majority of cables that were made when USB1 was all there was will operate
> quite happily at USB2 speeds, there are some that won't. In particular some
> USB1 cables were only designed to operate at the USB1 low speed and only had
> simple twisted pair cables. These definitely won't work at USB2 speeds.

There are lots of "USB" cables that are non-compliant (I find my "USB"
extension cord extremely useful -- and of course, it's not
compliant). Any compliant 1.1 cable will work with 2.0. A
non-compliant cable has no guarantees.

"Joe Pfeiffer" <> wrote in message
news:...
> "M.I.5¾" <_SPAM.co.uk> writes:
>> >
>> > 1. Is there a difference between cables.
>> >
>>
>> Yes - and No. Although any cable that operates at USB2* speeds will also
>> operate at USB1, the reverse is not necessarily true. Although the vast
>> majority of cables that were made when USB1 was all there was will
>> operate
>> quite happily at USB2 speeds, there are some that won't. In particular
>> some
>> USB1 cables were only designed to operate at the USB1 low speed and only
>> had
>> simple twisted pair cables. These definitely won't work at USB2 speeds.
>
> There are lots of "USB" cables that are non-compliant (I find my "USB"
> extension cord extremely useful -- and of course, it's not
> compliant). Any compliant 1.1 cable will work with 2.0. A
> non-compliant cable has no guarantees.

Non compliant with what?

Previously "M.I.5¾" <_spam.co.uk> wrote:

> "Joe Pfeiffer" <> wrote in message
> news:...
>> "M.I.5¾" <_SPAM.co.uk> writes:
>>> >
>>> > 1. Is there a difference between cables.
>>> >
>>>
>>> Yes - and No. Although any cable that operates at USB2* speeds will also
>>> operate at USB1, the reverse is not necessarily true. Although the vast
>>> majority of cables that were made when USB1 was all there was will
>>> operate
>>> quite happily at USB2 speeds, there are some that won't. In particular
>>> some
>>> USB1 cables were only designed to operate at the USB1 low speed and only
>>> had
>>> simple twisted pair cables. These definitely won't work at USB2 speeds.
>>
>> There are lots of "USB" cables that are non-compliant (I find my "USB"
>> extension cord extremely useful -- and of course, it's not
>> compliant). Any compliant 1.1 cable will work with 2.0. A
>> non-compliant cable has no guarantees.

> Non compliant with what?

The UBS standard? It does specify cable properties. IF they are
met the cables work fine with USB 2.0.

Arno

"M.I.5¾" <_SPAM.co.uk> writes:

> "Joe Pfeiffer" <> wrote in message
> news:...
> >
> > There are lots of "USB" cables that are non-compliant (I find my "USB"
> > extension cord extremely useful -- and of course, it's not
> > compliant). Any compliant 1.1 cable will work with 2.0. A
> > non-compliant cable has no guarantees.
>
> Non compliant with what?

With the USB specification.