Results 1 to 10 of 10

Thread: are usb 2.0 devices able to work with usb 1.1 hubs?

  1. #1
    Newbie
    Join Date
    Mar 2004
    Posts
    52

    are usb 2.0 devices able to work with usb 1.1 hubs?

    i believe the usb port on my laptop is usb 1.1. most of the devices out there are usb 2.0. i want to plug a usb hub into the laptop so i can have 4 ports instead of 1.

    is usb 2.0 backwards compatible with usb 1.1? i'm almost sure it is, but i want to be 110% sure before i spend money on a hub. i would think that the devices would auto-negotiate a mutually supported speed. (1.5Mbps, 12Mbps or 480Mbps.)

    thanks

  2. #2
    Maximum Bitrate d_sellers1's Avatar
    Join Date
    Mar 2002
    Location
    Austin, Texas
    Posts
    856
    Yes. USB2.0 is backwards compatible. When connected to 1.1, however, they run at 1.1 speeds.

    Derek
    Progress [||-------]
    View my Worklog to see some of my progress.
    Downgraded Progress - Starting with another car... 09/13/06

  3. #3
    Newbie
    Join Date
    Mar 2004
    Posts
    52
    that's what i needed to hear!

    thanks

  4. #4
    Maximum Bitrate d_sellers1's Avatar
    Join Date
    Mar 2002
    Location
    Austin, Texas
    Posts
    856
    Kinda along the same lines: Whenever you attached a 1.1 device to a 2.0 hub, it will drop the speed of all the devices to 1.1.

    FYI,
    Derek
    Progress [||-------]
    View my Worklog to see some of my progress.
    Downgraded Progress - Starting with another car... 09/13/06

  5. #5
    Nic
    Nic is offline
    FLAC Nic's Avatar
    Join Date
    Oct 2003
    Location
    Melbourne, Australia
    Posts
    1,047
    thats the wierdest first post ever

  6. #6
    Maximum Bitrate deadweasel's Avatar
    Join Date
    Nov 2003
    Location
    Detroit MI
    Posts
    886
    Guys, there are a couple instances where USB2.0 devices will NOT work on 1.1 ports.

    Case in point : I have an Enermax external HDD enclosure. Typically, under Win XP Pro, drivers are not needed, since XP sees it as another internal HDD. However, try as I might, I could not get it to work on 1.1 ports.

    I would get the little "help" balloon saying "You have plugged a USB2 device into a 1.1 port. Your new hardware is installed, but may not be useable etc etc"
    The drive would not show up no matter what. Until, that is, I went out and got a USB2 card for my PC, and then, wonder of wonders, the drive takes a moment, scanning the files as if it were a newly-inserted CD, then pops up for perusing in My Computer.

    Heh.
    The ALEXIS Project
    MP3---VIDEO---GPS---REARVIEW---OBD---SKINNING
    Color Coding :
    DONE / MOSTLY DONE / BASE FEATURES / WORKING CONCEPT / NO CODE COMPLETED

  7. #7
    Newbie
    Join Date
    Oct 2003
    Posts
    48
    Quote Originally Posted by d_sellers1
    Kinda along the same lines: Whenever you attached a 1.1 device to a 2.0 hub, it will drop the speed of all the devices to 1.1.

    FYI,
    Derek

    Not actually......


    When you connect a 1.1 device to a 2.0 hub only that device will operate at 1.1 speeds. All other devices will continue to run at 2.0 speeds. I've never seen a 2.0 hub that worked the other way.

  8. #8
    Maximum Bitrate Yuriy's Avatar
    Join Date
    Jun 2004
    Location
    Seattle
    Posts
    817
    I think it works like this:

    You can plug USB 1.1 devices into USB 2.0 port and they will work.
    But, not the other way around.
    00 Saturn SL2, boosted @ 8 psi - CarDomain
    Newest install - my quickest ever
    My 2nd carputer - b4 I broke the touchscreen
    My very first carputer - voted the most ghetto

  9. #9
    Maximum Bitrate d_sellers1's Avatar
    Join Date
    Mar 2002
    Location
    Austin, Texas
    Posts
    856
    Quote Originally Posted by stevewm
    Not actually......


    When you connect a 1.1 device to a 2.0 hub only that device will operate at 1.1 speeds. All other devices will continue to run at 2.0 speeds. I've never seen a 2.0 hub that worked the other way.
    These are excerpts from the DLink DUB-H7 USB hub manual:
    Remember that when connecting USB 1.1 devices to a USB 2.0 hub or host adapter, the USB 1.1 device will operate only at USB 1.1 speed.
    Connecting USB 1.1 devices to the DUB-H7 may cause all USB devices connected to the hub to work at USB 1.1 speed. To ensure 480Mbps throughput for your USB 2.0 devices, do not connect USB 1.1 and USB 2.0 devices to the hub at the same time.
    Quote Originally Posted by Yuriy
    I think it works like this:

    You can plug USB 1.1 devices into USB 2.0 port and they will work.
    But, not the other way around.
    This isn't true. You can plug a 2.0 device into a 1.1 port. It will operate at the slower speed. Windows will also give you an error saying that there is a high speed device plugged into a low speed port. The device works fine but not at full speed. For example, if you have a 48x USB CD burner when you plug it into a 1.1 port it will only burn at 4x (sometimes 6x or 8x).

    Derek
    Progress [||-------]
    View my Worklog to see some of my progress.
    Downgraded Progress - Starting with another car... 09/13/06

  10. #10
    Maximum Bitrate Yuriy's Avatar
    Join Date
    Jun 2004
    Location
    Seattle
    Posts
    817
    That's weird though, because apart from the connector the USB 1.1 and 2.0 don't look/act much differently.
    00 Saturn SL2, boosted @ 8 psi - CarDomain
    Newest install - my quickest ever
    My 2nd carputer - b4 I broke the touchscreen
    My very first carputer - voted the most ghetto

Similar Threads

  1. Cliffs: USB 1.1 sucks
    By frodobaggins in forum General MP3Car Discussion
    Replies: 10
    Last Post: 07-02-2004, 03:41 AM
  2. USB 2.0 drivers without SP1 WINXP
    By videodok in forum Software & Software Development
    Replies: 11
    Last Post: 12-11-2003, 07:04 AM
  3. has anyone got girder 3.2 to work with ME 2.0?
    By bertybassett in forum ME Archive
    Replies: 9
    Last Post: 11-06-2003, 02:35 AM
  4. Replies: 0
    Last Post: 09-08-2003, 11:15 AM
  5. Replies: 3
    Last Post: 04-09-2003, 10:48 AM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •