ZKBio900 Series User Manual
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Legacy USB Support [Enabled]
This item is used to enable or disable USB device. When set to the default value [Auto], the
system can automatically detect whether there is a USB device exists, if so, then start the USB
controller; otherwise it will not start. However, if you set this item to [Disabled], the USB controller
in the system is turned off regardless of the presence or absence of the USB device. setting
options
：
[Disabled] [Enabled] [Auto]
XHCI HAND-OFF
[Enabled]
This item and EHCI HAND-OFF, are used to select whether EFI releases control of the USB
controller before the OS loads the USB driver. If you select Enabled, EFI closes XHCI (USB2.0)
when entering OS.
EHCI Hand-off [Disabled]
This item is used to start an operating system that does not support the EHCI hand-off function.
Setting options: [Disabled] [Enabled]. If you select Enabled, EFI closes EHCI (USB2.0) when
entering OS.
USB Mass Storage Driver Support [Enabled]
USB Mass Storage Driver, setting options
：
[Disabled] [Enabled]
。
USB Transfer time-out [20sec]
This item sets the maximum time for a data transfer on the USB2.0. If the transmission is not
completed within this time, the error is given to the EFI. This setting only works on EFI, no effect to
