Re: USB2.0 Camera says this device can perform faster by M
M
Tue Apr 15 00:51:49 PDT 2008
"smlunatick" <yveslec@gmail.com> wrote in message
news:c333ad0d-b140-491a-b6f2-afb1f5361db0@u3g2000hsc.googlegroups.com...
On Apr 14, 8:27 am, "M.I.5¾" <no....@no.where.NO_SPAM.co.uk> wrote:
> <chadwpeter...@gmail.com> wrote in message
>
> news:7ab2ec32-6c35-4d09-b2ff-69404dae810c@q27g2000prf.googlegroups.com...
> On Apr 11, 11:09 am, chadwpeter...@gmail.com wrote:
>
> > I have a Dell Latitude D620 notebook with Windows XP SP2. Whenever I
> > connect devices that are USB2 capable, they function at USB2 speeds,
> > EXCEPT my Sony DSC-S500 camera. Every time I connect it, I get the
> > "This Device can perform faster...." popup in the system tray. The
> > camera is USB2.0 capable, and is the only device that I have this
> > issue with. I have tried unistalling the USB Mass Storage Device in
> > the Device Manager, but that did nothing for me. Any help would be
> > appreciated.
>
> I was able to do some more reading and found the answer I was looking
> for. My camera is "Full Speed USB2.0 Compatible", not "Hi-Speed
> USB2.0". Here is the information that I found:
>
> ***********************************************
> A couple of readers have also mentioned the old "Hi-Speed"/"Full
> Speed" problem. "Hi-Speed" is the 480 megabit per second speed
> (theoretically, at least - no USB 2 device actually manages to move
> more than about 240 megabits per second) that people think of when
> they see "USB 2" on a sticker.
>
> "Full Speed" is the old 12 megabit per second speed that was the most
> USB 1 could manage. So someone who's trying to rip people off could
> make a label that says "USB 2 Full Speed!" or something and kinda-
> sorta be telling the truth. It's perfectly possible to have a device
> that's fully compliant with the USB 2.0 spec, but which doesn't use Hi-
> Speed mode. Usually, that's because the device has no need for Hi-
> Speed, because it's a mouse or a keyboard or a USB sound "card" or
> something.
>
> This is a technical quibble, though. If you see "USB 2" on the label
> of a storage device, you should obviously expect it to be able to
> transfer data faster than a USB 1 device could, just as you should
> expect a car sold as having a turbocharger to have that turbocharger
> actually plumbed into the engine.
>
> ***********************************************
>
> So.. it looks like the camera is not capable of going any faster than
> 12Mbps after all.
>
> ----------------
>
> You are right about the USB2 specs and the anomoly it has created. And
> Sony *is* a company that has resorted to describing fast speed only
> equipment as USB2. However a device which is not high speed capable should
> not produce the perform faster error message.
>
> My junior spies tell me that the camera you refer to should be a high
> speed
> USB capable device. The first thing to do therefore is check the cable
> being used to connect it - try a cable known to work at high speed. I have
> noticed that Sony have taken to supplying some fairly abysmal bits of
> string. If that doesn't work, try the camera on another High speed capable
> PC. If that too gives you the error message, then it is most likely that
> the High speed port part of the camera is faulty. The fast and high speed
> ports are physically different ports that are switched automatically as
> required.
>
> If the camera has developed a fault, you can always put the memory stick
> into a true USB2 external reader and read it that way at high speed.
Full speed of 12 megabit is supposed to be USB 1.1. USB 1.0 is
supposed to be slower than that (11 megabit.)
--------------
Not correct. USB1.0 is a specification for a dual speed serial bus system
of 12 Mbps (fast mode) and 1.5 Mbps (slow mode). USB1.1 corrected a mis
specification of timing requirements for peripheral devices to improve
reliability of connection. As far as a PC is concerned, there is no
difference between USB1.0 and USB1.1. It only affects peripheral signal
timing and not the actual speed.