AMD SC3200 manual Bit Description Read PortEnableStatus, Read CurrentConnectStatus, 1510

Core Logic Module - USB Controller Registers - PCIUSB 32581C

			Table 6-42. USB_BAR+Memory Offset: USB Controller Registers (Continued)
Bit		Description
1		Read: PortEnableStatus.
		0:	Port disabled.
		1:	Port enabled.
		Write: SetPortEnable. Writing a 1 sets PortEnableStatus. Writing a 0 has no effect.
0		Read: CurrentConnectStatus.
		0:	No device connected.
		1:	Device connected.
		If DeviceRemoveable is set (not removable) this bit is always 1.
		Write: ClearPortEnable. Writing 1 a clears PortEnableStatus. Writing a 0 has no effect.
Note:	This register is reset by the UsbReset state.
Offset 58h-5Bh				HcRhPortStatus[2] Register (R/W)	Reset Value = 00000000h
31:21		Reserved. Read/Write 0s.

20PortResetStatusChange. This bit indicates that the port reset signal has completed.

0:Port reset is not complete.

1:Port reset is complete.

19PortOverCurrentIndicatorChange. This bit is set when OverCurrentIndicator changes. Writing a 1 clears this bit. Writing a 0 has no effect.

18PortSuspendStatusChange. This bit indicates the completion of the selective resume sequence for the port.

0:Port is not resumed.

1:Port resume is complete.

17PortEnableStatusChange. This bit indicates that the port has been disabled due to a hardware event (cleared PortEna- bleStatus).

0:Port has not been disabled.

1:PortEnableStatus has been cleared.

16ConnectStatusChange. This bit indicates a connect or disconnect event has been detected. Writing a 1 clears this bit. Writing a 0 has no effect.

0:No connect/disconnect event.

1:Hardware detection of connect/disconnect event.

If DeviceRemoveable is set, this bit resets to 1.

15:10 Reserved. Read/Write 0s.

9Read: LowSpeedDeviceAttached. This bit defines the speed (and bud idle) of the attached device. It is only valid when CurrentConnectStatus is set.

0:Full speed device.

1:Low speed device.

Write: ClearPortPower. Writing a 1 clears PortPowerStatus. Writing a 0 has no effect.

8Read: PortPowerStatus. This bit reflects the power state of the port regardless of the power switching mode.

0:Port power is off.

1:Port power is on.

If NoPowerSwitching is set, this bit is always read as 1.

Write: SetPortPower. Writing a 1 sets PortPowerStatus. Writing a 0 has no effect.

7:5 Reserved. Read/Write 0s.

4Read: PortResetStatus.

0:Port reset signal is not active.

1:Port reset signal is active.

Write: SetPortReset. Writing a 1 sets PortResetStatus. Writing a 0 has no effect.

AMD Geode™ SC3200 Processor Data Book 291