USB Host Controller Registers
14-28
The HC root hub status register reports the USB host controller root hub status.
Table 14–22. HC Root Hub Status Register (HcRhStatus)
Bit
Name
Description
Type
Reset
Value
31
CRWE
Clear remote wake-up enable
Write of 0 has no effect.
Write of 1 clears the device remote wake-up enable bit.
R/W
0
30–18
Reserved
Reserved
17
OCIC
Overcurrent indication change
This bit is automatically set when the overcurrent indicator bit
changes.
Write of 0 has no effect.
Write of 1 clears this bit.
R/W
0
16
LPSC
Local power status change
This bit defaults to 0 since the root hub does not support the
local power status feature.
Write of 0 has no effect.
Write of 1 sets the PortPowerStatus bits for all ports if
PowerSwitchingMode is 0. A write of 1 sets PortPowerStatus
bits for ports with their corresponding PortPowerControlMask
bits cleared if PowerSwitchingMode is 1.
R/W
0
15
DRWE
Device remote wake-up enable
When 1, this bit enables a ConnectStatusChange event to be
treated as a resume event, which causes a transition from
USBSuspend to USBResume state, and sets the
ResumeDetected interrupt status bit.
When 0, ConnectStatusChange events do not cause a
transition from USBSuspend to USBResume state and the
ResumeDetected interrupt is not changed.
Write of 0 has no effect.
Write of 1 sets the device remote wake-up enable bit.
R/W
0
14–2
Reserved
Reserved