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On Fri, Feb 27, 2009 at 3:21 PM, Grant <emailgrant@×××××.com> wrote: |
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>>>> I'm looking at the box of one of the webcams and it says "USB 2.0 |
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>>>> compatible". |
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>>>> |
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>>> |
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>>> A USB 1.1 device _is_ "USB 2.0 compatible" because a USB 2.0 |
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>>> will slow down and run at 1.1 speed. Does the device say it's |
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>>> "high speed" USB? "USB 2.0 compatible" generally means it's a |
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>>> USB 1.1 device. |
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>>> |
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>>> |
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>>>> It's not a cable problem because the cable is built right into |
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>>>> the webcam. I'm not trying to get the webcam to go faster |
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>>>> back and forth to the controller, I just need to make sure I |
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>>>> don't have both webcams on the same OHCI (1.1) USB controller. |
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>>>> I would think buying a USB expansion card would work, but I |
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>>>> have an EHCI (2.0) controller on this system and a second OHCI |
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>>>> (1.1) controller. |
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>>>> |
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>>>> Does anyone have any idea on this. It really doesn't make sense. |
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>>>> |
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>>> |
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>>> Sounds like it's a 1.1 device to me. |
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>>> |
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>>> |
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>> |
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>> Yep, that's what it sounds like to me too. |
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>> |
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>> Dale |
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> |
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> But that's OK isn't it? I don't need 2.0 speeds between each webcam |
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> and the controller, I just need the increased overall bandwidth of a |
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> 2.0 controller so one of the 1.1 webcams doesn't use all of it. I get |
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> the feeling I have a misconception somewhere along the line here. |
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> Could someone straighten me out? |
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> |
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> - Grant |
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|
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The controller itself has the full bandwidth of the 2.0 spec, it's |
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just only able to allocate the bandwidth of the 1.0/1.1 spec to each |
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of the cameras because they're being recognized as 1.1 capable only. |
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The controller, though, I'm pretty sure is able to allocate more than |
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enough overall bandwidth to the pair. Based on your original remarks |
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that "one of them isn't functioning", I worry more that there's a |
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problem with the driver for the camera itself that somehow breaks with |
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two of the same camera present, broken udev rule somewhere that's not |
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creating the device for the second camera, or... *something* more |
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along those lines, rather than an issue with the on-chip |
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implementation of your usb controller. |
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|
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-- |
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Poison [BLX] |
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Joshua M. Murphy |