Samsung S5PC100, User Manual

Page: 834 / 1863

USB HOST CONTROLLER S5PC100 USER’S MANUAL (REV1.0)
8.9-34
5.2.21 USB HcRhStatus Register (UHCRHSTAT, Address = 0xED40_0050)
The UHC Root Hub Status register is divided into two parts. The lower word of a word represents the Hub Status
field and the upper word represents the Hub Status Change field.
Table 8.9-21 UHCRHSTAT Bit Definitions
UHCRHSTAT Bit Description R/W Reset Value
CRWE [31] ClearRemoteWakeupEnable
Writing a 1 clears the device remote wake-up enable
(UHCRHS[DRWE]) bit. Writing a 0 has no effect. This bit
always reads as 0. R/W
Reserved [30:18] Read as unknown and must be written as zero. -
OCIC [17] OverCurrentIndicatorChange
This bit is set by hardware if a change has occurred to the
OCI field of this register. The HCD clears this bit by
writing a 1. Writing a 0 has no effect.
1 = A change has occurred to the OCI field of this register
R/WC
LPSC [16] (read) LocalPowerStatusChange / (write)
SetGlobalPower: wake-up
The root hub does not support the local power status
feature; thus, this bit is always read as 0. In global power
mode (UHCRHDA[PSM] is clear), this bit is written to 1 to
turn on power to all ports (set Goal Port Power). In per-
port power mode, this bit sets PortPowerStatus
(UHCRHPS1/2/3[PPS]) only on ports whose port power
control mask bit (UHCRHDB[PPCM]) is not set. Writing a
0 has no effect. This bit is always read as 0. R/W
DRWE [15] (read) DeviceRemoteWakeupEnable / (write)
SetRemoteWakeupEnable
This bit enables a ConnectStatusChange bit
(UHCRHPS1/2/3[CSC]) as a resume event, causing a
USBSUSPEND-to-USBRESUME state transition and
setting the resume-detected interrupt. If it reads 0, a
ConnectStatusChange is not a remote wake-up event. If it
is read as a 1, ConnectStatusChange is a remote wake-
up event. Writing a 1 sets the device remote wake-up
enable (this bit). Writing a 0 has no effect.
0 = ConnectStatusChange is not a remote wake-up R/W