Difference between usb1.1 and usb2.0 cable? 1

[garebo]

I have had people tell me that any usb cable will do the job and i have had others say you must have a usb2.0 cable if you want a usb2.0 product to perform at the usb2.0 level. I do believe you need a usb2.0 cable for a usb2.0 product, but i would like to hear from some of the pro's around here.

The second part of this: Is there any way to test the speed of your usb transfer? Seems to me that i read a microsoft info page on that and if i recall correctly you need special testing equipment to test for usb speed and thus test for usb1.1 or usb2.0. Is that correct?

thanks



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[xwb]

The main difference is in the wire quality and shielding. The USB 2.0 cables are better quality. If you use a USB 1.1 cable, it will still work but you may not get the same throughput.

Try this site for most things you want to know about USB and some things you don't.

http://www.usbman.com/USB_Guides.htm

 

[garebo]

Thanks, i will have a look.
Would like to see some more input here.


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[cdogg]

Go to this link and scroll to the bottom:

http://www.everythingusb.com/usb2/faq.htm

As you can see, certified USB 1.1 cables will work for USB 2.0 speeds. However, it estimates that only 3 out 11 USB 1.1 cables sold over the years were compliant with the specification. Therefore, there's a high chance you'll run into an old cable that won't work.

This is why they recommend you buy a USB 2.0 compliant cable to be sure (which is really just the same as a USB 1.1 compliant cable, with perhaps some better shielding as xwb pointed out).

~cdogg
[tab][navy]For general rules and guidelines to get better answers, click here:[/navy] faq219-2884

 

[garebo]

ok, thanks guys!
Now, what about the second part of this thread? Any easy way to test to see what speed a person is getting from their usb product, short of having a bunch of test equipment?

thanks


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[garebo]

Lots of good info at these 2 sites, one of which i have been there before.
Still cant find anything relating to testing speed.


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[cdogg]

garebo,

When it comes to testing, there are two main kinds: actual and theoretical transfer rates.

To test the theoretical (480mbps) of the port itself, you do need special testing equipment as far as I know. But that shouldn't matter. What you want to test is actual. If you are using a USB 2.0 storage device (such as a hard drive), then you can test the time it takes to transfer a file. You want to transfer a file to and from the device to test both write and read speads.

USB 1.1 maxes out at 1.5MB per second. USB 2.0 maxes at 60MB per second. These limits are only theoretical. Due to overhead, actual transfer rates will always be slower. If you are getting transfer times faster than 1.5MB per second (which shouldn't be hard with a hard drive), then you know the USB connection is running in 2.0 mode.

~cdogg
[tab][navy]For general rules and guidelines to get better answers, click here:[/navy] faq219-2884

 

[garebo]

Its been a heck of a long time to get an answer. I have posted this same item here before and i dont think i got a real good answer. And i posted it at another site before and didnt get a real answer. That is, to the speed question and to the measuring question.
So thanks very much, cdogg, for taking the time to do so.
I have been wanting this info for quite a while. I can get theoretical, but i wanted real-life!
And, yes, from what i have read, we would need testing equipment to do actual testing, but your figures should be good enough for most situations, so thanks again.


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