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# Uncorrectable Error Bits

Constants for the bits in the uncorrectable error status register.

## Topics

### Bit Numbers

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

The bit number that indicates a data link protocol error.

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

The bit number that indicates a surprise down error.

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

The bit number that indicates a poisoned transaction level packet

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

The bit number that indicates a flow control protocol error.

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

The bit number that indicates a completion timeout status error.

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

The bit number that indicates a completer abort status error.

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

The bit number that indicates an unexpected completion status error.

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

The bit number that indicates a receiver overflow status error.

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

The bit number that indicates a malformed transaction layer packet.

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

The bit number that indicates an ECRC error.

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

The bit number that indicates an unsupported request error.

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

The bit number that indicates an ACS violation error.

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

The bit number that indicates an uncorrectable internal error.

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

The bit number that indicates an MC blocked TLP status error.

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

The bit number that indicates an AtomicOp egress blocked error.

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

The bit number that indicates a TLP prefix blocked error.


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