Revision 1.1
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G
Core Logic Module
(Continued)
Offset 0Ch-0Fh
HcInterruptStatus Register (R/W)
Reset Value = 00000000h
31
Reserved.
Read/Write 0s.
30
OwnershipChange.
This bit is set when the OwnershipChangeRequest bit of HcCommandStatus is set.
29:7
Reserved.
Read/Write 0s.
6
RootHubStatusChange.
This bit is set when the content of HcRhStatus or the content of any HcRhPortStatus register has
changed.
5
FrameNumberOverflow.
Set when bit 15 of FrameNumber changes value.
4
UnrecoverableError (Read Only).
This event is not implemented and is hard-coded to 0. Writes are ignored.
3
ResumeDetected.
Set when HC detects resume signaling on a downstream port.
2
StartOfFrame.
Set when the Frame Management block signals a Start of Frame event.
1
WritebackDoneHead.
Set after the HC has written HcDoneHead to HccaDoneHead.
0
SchedulingOverrun.
Set when the List Processor determines a Schedule Overrun has occurred.
Note:
All bits are set by hardware and cleared by software.
Offset 10h-13h
HcInterruptEnable Register (R/W)
Reset Value = 00000000h
31
MasterInterruptEnable.
This bit is a global interrupt enable. A write of 1 allows interrupts to be enabled via the specific
enable bits listed above.
30
OwnershipChangeEnable.
0: Ignore.
1: Enable interrupt generation due to Ownership Change.
29:7
Reserved.
Read/Write 0s.
6
RootHubStatusChangeEnable.
0: Ignore.
1: Enable interrupt generation due to Root Hub Status Change.
5
FrameNumberOverflowEnable.
0: Ignore.
1: Enable interrupt generation due to Frame Number Overflow.
4
UnrecoverableErrorEnable.
This event is not implemented. All writes to this bit are ignored.
3
ResumeDetectedEnable.
0: Ignore.
1: Enable interrupt generation due to Resume Detected.
2
StartOfFrameEnable.
0: Ignore.
1: Enable interrupt generation due to Start of Frame.
1
WritebackDoneHeadEnable.
0: Ignore.
1: Enable interrupt generation due to Writeback Done Head.
0
SchedulingOverrunEnable.
0: Ignore.
1: Enable interrupt generation due to Scheduling Overrun.
Note:
Writing a 1 to a bit in this register sets the corresponding bit, while writing a 0 leaves the bit unchanged.
Table 5-42. USB_BAR+Memory Offset: USB Controller Registers (Continued)
Bit
Description