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How enable "USB Legacy support" on SN78SH7 Shuttle

By zog
Nov 2, 2009
  1. I have a Shuttle SN78SH7 with the latest SN78S10Y BIOS. I had been using a wired USB KB, which works fine. I recently switched to a wireless KB, but it does not work during POST or the grub2 menu. It works fine though once the OS boots up.

    I understand I should try enabling "Legacy USB support" in the BIOS, but I can't find that in the menu. Can someone point me to the right setting?

    -Thanks, zog
     
  2. Tmagic650

    Tmagic650 TS Ambassador Posts: 17,244   +234

    You need to keep Legacy USB support turned off and use a USB to PS2 keyboard adapter
     
  3. zog

    zog TS Rookie Topic Starter

    The wireless KB has a USB dongle, so I can't use a PS/2 adapter. (Since the wired USB KB works fine, so I don't need a PS/2 adapter with that either.)

    I also don't know which setting in the BIOS is for Legaccy USB support enable/disable.

    -zog
     
  4. zog

    zog TS Rookie Topic Starter

    can't use PS/2 adapter

    The wireless KB has a USB dongle, so I can't use a PS/2 adapter. (Since the wired USB KB works fine, so I don't need a PS/2 adapter with that either.)

    I also don't know which setting in the BIOS is for Legaccy USB support enable/disable.

    -zog
     
  5. LookinAround

    LookinAround Ex Tech Spotter Posts: 6,491   +183

    Why (or when) would one need to keep USB legacy turned off? just curious as i hadn't heard that before nor ever done so myself
     
  6. LookinAround

    LookinAround Ex Tech Spotter Posts: 6,491   +183

    Hi Zog

    What kind of wireless KB do you have?
    > Typically, if a wired USB keyboard works at bootup (i.e. before Windows starts) so should a wireless KB
    > As typically the communication between KB and wireless antennae has nothing to do with USB support (short of the USB port supplying power to the antennae)
    > So i wonder if USB legacy isn't already enabled as you report the wired USB is working
     
  7. Tmagic650

    Tmagic650 TS Ambassador Posts: 17,244   +234

    It depends on the motherboard/bios... I had a Gigabyte motherboard that I had to turn off legacy USB support to detect a USB keyboard during boot. My current Abit IP35 Pro doesn't need USB legacy turned off, although it won't detect an F8 key press
     
  8. LookinAround

    LookinAround Ex Tech Spotter Posts: 6,491   +183

    Oops. i should re-phrase what i meant in my earlier post.

    On the one hand...
    I do know in earlier USB days, it was sometimes required to turn USB legacy off in BIOS in order for USB to work correctly once Windows was started

    However...
    I'd never heard of turning it off in order get USB to work before Windows starts (i.e.. while BIOS is still in control of the peripherals) which what i understand Zog is trying to do

    For Zog's case: i'm also a bit surprised to learn USB wired works in BIOS but not USB wireless (as from the BIOS perspective, i wouldn't think it even knows the difference between the two vs. just seeing a USB device being connected. The antennae <==> keyboard wireless communication is strictly between the antennae and keyboard and independent of USB)

    From my own experience (and i have a Logitech MX3200 wireless keyboard/mouse) the wireless keyboard works fine 90% (but not 100%) of the time during BIOS boot. I haven't explored why that 10% of the time the key presses aren't detected

    /* editt */
    Zog: During the BIOS boot (when still waiting for keyboard input) have you tried resync'ing the antennae and keyboard? (There's usually a button to click on both antennae and keyboard to do so)
     
  9. Tmagic650

    Tmagic650 TS Ambassador Posts: 17,244   +234

    Yes LookinAround,
    with that Gigabyte board, it would not complete the boot process with my iPod connected, if legacy USB was enabled. So I left it off. The wireless Logitech EX110 keyboard and mouse work either way. On boot up I can select one of 2 operating systems, but the computer won't "see" an F8 keypress to enter Safe Mode
     
  10. LookinAround

    LookinAround Ex Tech Spotter Posts: 6,491   +183

    Does that mean it does see up/down arrows and Enter (so you can select the OS) yet doesn't see the F8??
     
  11. Tmagic650

    Tmagic650 TS Ambassador Posts: 17,244   +234

    Yes exactly... Maybe it has something to do with the F-key being enabled or not at boot up
     
  12. LookinAround

    LookinAround Ex Tech Spotter Posts: 6,491   +183

    I wonder if your Logitech model handles "Function" keys somewhat different then "Standard" keys (e.g. i wouldn't be surprised if hot keys and programmable type keys aren't recognized by USB emulation in BIOS)

    One thought: Have you checked the Logitech website to see if there are any firmware and/or driver updates for your antennae and/or keyboard?
     
  13. LookinAround

    LookinAround Ex Tech Spotter Posts: 6,491   +183

    @Tmagic
    In addition to firmware/software updates, look for an F lock key as well on your keyboard (logitech calls it an F mode key i think see here)
    > Try toggling it on/off to see if F8 will work in BIOS

    @Zog
    You might also check for firmware/software updates for your USB wireless device
     
  14. Tmagic650

    Tmagic650 TS Ambassador Posts: 17,244   +234

    LookinAround,
    I found out what the problem was. I had the Start Up & Recovery setting "Time to display recovery options" set to 0. I moved the slider to 15 seconds, and F8 is now functional
     
  15. LookinAround

    LookinAround Ex Tech Spotter Posts: 6,491   +183

    Thanks for the update. That's another bit of Windows minutia that's both good and handy to know! :)
     
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