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# Status Register Bits

Constants that you use to access specific bits of the status register.

## Topics

### Registers

[`kIOPCIStatusInterrupt`](/documentation/PCIDriverKit/kIOPCIStatusInterrupt)

The bit that contains the interrupt status.

[`kIOPCIStatusCapabilities`](/documentation/PCIDriverKit/kIOPCIStatusCapabilities)

The bit that indicates the presence of an extended capability list item.

[`kIOPCIStatusPCI66`](/documentation/PCIDriverKit/kIOPCIStatusPCI66)

The bit that indicates the device is capable of 66 MHz operation.

[`kIOPCIStatusUDF`](/documentation/PCIDriverKit/kIOPCIStatusUDF)

The bit that indicates the status of UDF support.

[`kIOPCIStatusFastBack2Back`](/documentation/PCIDriverKit/kIOPCIStatusFastBack2Back)

The bit that indicates whether the device is capable of fast back-to-back transactions.

[`kIOPCIStatusTargetAbortCapable`](/documentation/PCIDriverKit/kIOPCIStatusTargetAbortCapable)

The bit that indicates whether a function completed a posted or non-posted request as a completer abort error.

[`kIOPCIStatusTargetAbortActive`](/documentation/PCIDriverKit/kIOPCIStatusTargetAbortActive)

The bit that indicates whether a requester received a completion with a completer abort completion status.

[`kIOPCIStatusMasterAbortActive`](/documentation/PCIDriverKit/kIOPCIStatusMasterAbortActive)

The bit that indicates whether a requester received a completion with an unsupported request completion status

[`kIOPCIStatusSERRActive`](/documentation/PCIDriverKit/kIOPCIStatusSERRActive)

The bit that indicates whether a function sent a fatal or nonfatal error message and set the SERR enable bit in the command register.

[`kIOPCIStatusParityErrActive`](/documentation/PCIDriverKit/kIOPCIStatusParityErrActive)

The bit that indicates whether a function received a poisoned transaction-layer packet.

[`kIOPCIStatusDevSel0`](/documentation/PCIDriverKit/kIOPCIStatusDevSel0)

The DEVSEL timing status is set to 0.

[`kIOPCIStatusDevSel1`](/documentation/PCIDriverKit/kIOPCIStatusDevSel1)

The DEVSEL timing status is set to 1.

[`kIOPCIStatusDevSel2`](/documentation/PCIDriverKit/kIOPCIStatusDevSel2)

The DEVSEL timing status is set to 2.

[`kIOPCIStatusDevSel3`](/documentation/PCIDriverKit/kIOPCIStatusDevSel3)

The DEVSEL timing status is set to 3.

### Constants

[`kIOPCIStatusLeadAbortActive`](/documentation/PCIDriverKit/kIOPCIStatusLeadAbortActive)


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