FW82801DBM S L6DN Intel, FW82801DBM S L6DN Datasheet - Page 448

• Manufacturer Part Number: FW82801DBM S L6DN
• Manufacturer: Intel

Specifications of FW82801DBM S L6DN

• Lead Free Status / RoHS Status: Not Compliant

EHCI Controller Registers (D29:F7)
12.1.26
:
12.1.27
448
PORT_OVRIDE—USB UHCI Port Override Register
(USB EHCI—D29:F7)
Address Offset:
Default Value:
This feature is implemented with the following requirements:
LEG_EXT_CAP—USB EHCI Legacy Support Extended
Capability Register (USB EHCI—D29:F7)
Address Offset:
Default Value:
Power Well:
•
•
•
•
•
31:25
23:17
15:8
15:6
7:0
5:1
Bit
Bit
24
16
0
The associated Port Owner bit does not reflect the value in this register.
BIOS must only write to this register during initialization, while the Configured Flag bit is 0.
The register is implemented in the Suspend well to maintain port routing when the core power
goes down.
When a 1 is present in the Override register, then the USB UHCI controller operates the port
regardless of the EHCI port routing logic. The corresponding EHCI port will always appear
disconnected in this mode.
Port 0 must never be programmed to the USB UHCI Override mode. This is because the
Debug Port is used on Port 0 and the two modes conflict with each other.
Reserved — RO. Hardwired to 00h
HC OS Owned Semaphore — R/W. System software sets this bit to request ownership of the EHCI
controller. Ownership is obtained when this bit reads as 1 and the HC BIOS Owned Semaphore bit
reads as clear.
Reserved — RO. Hardwired to 00h
HC BIOS Owned Semaphore — R/W. The BIOS sets this bit to establish ownership of the EHCI
controller. System BIOS will clear this bit in response to a request for ownership of the EHCI
controller by system software.
Next EHCI Capability Pointer — RO. A value of 00h indicates that there are no EHCI Extended
Capability structures in this device.
Capability ID — RO. A value of 01h indicates that this EHCI Extended Capability is the Legacy
Support Capability.
Reserved
USB UHCI Port Owner — R/W.
0 = No override on the corresponding port.
1 = Forces the corresponding USB port to be owned by the appropriate USB UHCI Host Controller.
Reserved
Suspend
64
0000h
68
00000001h
–
–
65h
6Bh
Description
Description
Attribute:
Size:
Attribute:
Size:
Intel
R/W
16 bits
R/W, RO
32 bits
®
82801DBM ICH4-M Datasheet