NO:
W90P710 Programming Guide
VERSION:
2.1
PAGE:
91
The above information is the exclusive intellectual property of Winbond Electronics and shall not be disclosed,
distributed or reproduced without permission from Winbond.
Table No.: 1200-0003-07-A
•
Ports
are
power
switched
•
Power switching mode is global power switch
•
Is not a compound device
•
Over-current status is reported collectively for all downstream ports
•
Power-on-to-power-good-time
is
2ms
•
Devices attached to any ports are removable
6.5.8.2
HcRhStatus
The
HcRhStatus
register is used to control and monitor the
Root Hub
status. The
Root Hub
can
be controlled by the following actions :
•
ClearGlobalPower
– write ‘1’ to bit 0 to turn off power to all ports
•
SetRemoteWakeupEnable
– write ‘1’ to bit 15 to enable device remote wakeup
•
SetGlobalPower
– write ‘1’ to bit 16 to turn off power to all ports
•
ClearRemoteWakeupEnable
– write ‘1’ to bit 31 to disable device remote wakeup
In addition, the
HcRhStatus
register also indicates the following status :
•
OverCurrentIndicator
– bit 2 indicates the over-current status
•
DeviceRemoteWakeupEnable
– bit 15 indicates the remote wakeup status. If this bit
was set, the ConnectStatusChange is determined as a remote wakeup event
•
OverCurrentIndicatorChange
– This bit was set when the
OverCurrentIndicator
bit
changed
6.5.8.3
HcRhPortStatus[1] and HcRhPortStatus[2]
The
HcRhPortStatus[1]
and
HcRhPortStatus[1]
register is used to control and monitor the
Root
Hub
port status.
HcRhPortStatus[1]
is dedicated to port 0 and
HcRhPortStatus[2]
dedicated to port
1 respectively. The lower word is used to reflect the port status, whereas the upper word is used to
reflect the changing of lower word status bits. Some status bits are implemented with special write
behavior. You can do the following actions to control the
Root Hub
port :