meaning the controller then needs different outlets for 3.0 and 2.0 cables,
so I need to use 3.0 cable on the 3.0 one, but 2.0 cable on the other.
sounds reasonable.
thanks
michael
--
Michael Scherer
Univ.klinik f. Psychiatrie
email: michael.scherer@...
phone: +43 6991 941 22 54
----- Original Message -----
From: "Paul Hartman" <paul.hartman+gentoo@...>
To: <gentoo-amd64@g.o>
Sent: Monday, 07 May, 2012 23:45
Subject: Re: [gentoo-amd64] Drivers For USB HDD
> On Mon, May 7, 2012 at 4:18 PM, Michael Scherer
> <a6702894@...> wrote:
>>> On Mon, May 7, 2012 at 8:21 AM, Paul Hartman
>>> <paul.hartman+gentoo@...> wrote:
>>>>
>>>> On Mon, May 7, 2012 at 10:00 AM, Mark Knecht <markknecht@...>
>>>> wrote:
>>>>>
>>>>> here are 3 or now I
>>>>> think 4 different USB specs - EHCI, OHCI, UHCI, and then whatever USB
>>>>> 3.0 is using
>>>>
>>>>
>>>> XHCI
>>>>
>>>> Furthermore, USB 3.0 has 9-pin ports and cables (for type-A) versus
>>>> the 4-pin of USB 1/2. The USB 3.0 sockets are backward-compatible with
>>>> older USB devices and cables, but older USB cables are not
>>>> forward-compatible with USB 3.0.
>>>>
>>>
>>> Good point. None of my USB 2.0 drives work in my USB 3.0 port. I do
>>> have a USB 3.0 drivers, supposedly, and one drive that claims to be
>>> eSata/USB 3.0 compatible, but I've not tried to get it working using
>>> USB 3.0.
>>>
>>> - Mark
>>>
>>>
>>
>
>> Seems this either a typo, or a contradiction:
>> "The USB 3.0 sockets are backward-compatible with older ... cables"
>> would mean I can use the old cables for 3.0, but then
>>
>> "but older USB cables are not forward-compatible with USB 3.0"
>> says I can NOT use the old cables.
>> I have no 3.0, but some day I probably will, so I'd like to know what
>> exactly you mean.
>>
>> kind regards
>>
>> michael
>
> Hi,
>
> Here is what I mean:
>
> USB 3.0 socket is backwards compatible = USB 2.0 cable and devices
> still work as USB 2.0 when plugged into USB 3.0 port.
>
> USB 2.0 cable is not forward-compatible = you can not use USB 2.0
> cable with USB 3.0 device as USB 3.0. It will only behave as USB 2.0
> in that case.
>
> If you want to truly use USB 3.0 you need to have all three: USB 3.0
> port, USB 3.0 cable, USB 3.0 device.
>
>
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