AMD Offset 50h-53h HcRhStatus Register R/W, 3018, AMD Geode SC3200 Processor Data Book 289

Core Logic Module - USB Controller Registers - PCIUSB 32581C

Table 6-42. USB_BAR+Memory Offset: USB Controller Registers (Continued)

Bit		Description
7:0		NumberDownstreamPorts (Read Only). USB supports three downstream ports.
Note:	This register is only reset by a power-on reset (PCIRST#). It is written during system initialization to configure the Root Hub.
	These bit should not be written during normal operation.
Offset 4Ch-4Fh			HcRhDescriptorB Register (R/W)	Reset Value = 00000000h
31:16		PortPowerControlMask. Global-power switching. This field is only valid if NoPowerSwitching is cleared and Power-
		SwitchingMode is set (individual port switching). When set, the port only responds to individual port power switching com-
		mands (Set/ClearPortPower). When cleared, the port only responds to global power switching commands (Set/
		ClearGlobalPower).

0:Device not removable.

1:Global-power mask.

Port Bit relationship - Unimplemented ports are reserved, read/write 0. 0 = Reserved

1 = Port 1

2 = Port 2

...

15 = Port 15

15:0	DeviceRemoveable. USB ports default to removable devices.
	0:	Device not removable.
	1:	Device removable.
	Port Bit relationship
	0	= Reserved
	1	= Port 1
	2	= Port 2
	...
	15 = Port 15
	Unimplemented ports are reserved, read/write 0.

Note: This register is only reset by a power-on reset (PCIRST#). It is written during system initialization to configure the Root Hub. These bit should not be written during normal operation.

Offset 50h-53h HcRhStatus Register (R/W) Reset Value = 00000000h

31ClearRemoteWakeupEnable (Write Only). Writing a 1 to this bit clears DeviceRemoteWakeupEnable. Writing a 0 has no effect.

30:18 Reserved. Read/Write 0s.

17OverCurrentIndicatorChange. This bit is set when OverCurrentIndicator changes. Writing a 1 clears this bit. Writing a 0 has no effect.

16Read: LocalPowerStatusChange. Not supported. Always read 0.

Write: SetGlobalPower. Write a 1 issues a SetGlobalPower command to the ports. Writing a 0 has no effect.

15Read: DeviceRemoteWakeupEnable. This bit enables ports' ConnectStatusChange as a remote wakeup event.

0:Disabled.

1:Enabled.

Write: SetRemoteWakeupEnable. Writing a 1 sets DeviceRemoteWakeupEnable. Writing a 0 has no effect.

14:2 Reserved. Read/Write 0s.

1OverCurrentIndicator. This bit reflects the state of the OVRCUR pin. This field is only valid if NoOverCurrentProtection and OverCurrentProtectionMode are cleared.

0:No over-current condition. 1:Over-current condition.

0Read: LocalPowerStatus. Not Supported. Always read 0.

Write: ClearGlobalPower. Writing a 1 issues a ClearGlobalPower command to the ports. Writing a 0 has no effect.

Note: This register is reset by the UsbReset state.

AMD Geode™ SC3200 Processor Data Book 289