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IB990 User’s Manual
4.4.9
USB Configuration
BIOS Setting
Description
Legacy USB
Support
Enables Legacy USB support.
“Auto” disables legacy support if there is no
USB device connected.
“Disable” keeps USB devices available only
for EFI applications.
XHCI Hand-off
This is a workaround for OSes without XHCI
hand-off support. The XHCI ownership
change should be claimed by XHCI driver.
USB Mass Storage
Driver Support
Enables / Disables the support for USB
mass storage driver.
Port 60/64
Emulation
Enables I/O port 60h/64h emulation support.
This should be enabled for the complete
USB keyboard legacy support for non-USB
aware OSes.
USB Transfer
time-out
The time-out value for Control, Bulk, and
Interrupt transfers.
Device reset
time-out
Seconds of delaying execution of start unit
command to USB mass storage device.