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  "framework" : "IOUSBHost",
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  "title" : "IOUSBHost Constants"
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# IOUSBHost Constants

## Topics

### Constants

[`var IOUSBHostCIControllerStateActive: IOUSBHostCIControllerState`](/documentation/IOUSBHost/IOUSBHostCIControllerStateActive)

[`var IOUSBHostCIControllerStateOff: IOUSBHostCIControllerState`](/documentation/IOUSBHost/IOUSBHostCIControllerStateOff)

[`var IOUSBHostCIControllerStatePaused: IOUSBHostCIControllerState`](/documentation/IOUSBHost/IOUSBHostCIControllerStatePaused)

[`var IOUSBHostCIDeviceSpeedFull: IOUSBHostCIDeviceSpeed`](/documentation/IOUSBHost/IOUSBHostCIDeviceSpeedFull)

[`var IOUSBHostCIDeviceSpeedHigh: IOUSBHostCIDeviceSpeed`](/documentation/IOUSBHost/IOUSBHostCIDeviceSpeedHigh)

[`var IOUSBHostCIDeviceSpeedLow: IOUSBHostCIDeviceSpeed`](/documentation/IOUSBHost/IOUSBHostCIDeviceSpeedLow)

[`var IOUSBHostCIDeviceSpeedNone: IOUSBHostCIDeviceSpeed`](/documentation/IOUSBHost/IOUSBHostCIDeviceSpeedNone)

[`var IOUSBHostCIDeviceSpeedSuper: IOUSBHostCIDeviceSpeed`](/documentation/IOUSBHost/IOUSBHostCIDeviceSpeedSuper)

[`var IOUSBHostCIDeviceSpeedSuperPlus: IOUSBHostCIDeviceSpeed`](/documentation/IOUSBHost/IOUSBHostCIDeviceSpeedSuperPlus)

[`var IOUSBHostCIDeviceSpeedSuperPlusBy2: IOUSBHostCIDeviceSpeed`](/documentation/IOUSBHost/IOUSBHostCIDeviceSpeedSuperPlusBy2)

[`var IOUSBHostCIDeviceStateActive: IOUSBHostCIDeviceState`](/documentation/IOUSBHost/IOUSBHostCIDeviceStateActive)

[`var IOUSBHostCIDeviceStateDestroyed: IOUSBHostCIDeviceState`](/documentation/IOUSBHost/IOUSBHostCIDeviceStateDestroyed)

[`var IOUSBHostCIDeviceStatePaused: IOUSBHostCIDeviceState`](/documentation/IOUSBHost/IOUSBHostCIDeviceStatePaused)

[`var IOUSBHostCIEndpointStateActive: IOUSBHostCIEndpointState`](/documentation/IOUSBHost/IOUSBHostCIEndpointStateActive)

[`var IOUSBHostCIEndpointStateDestroyed: IOUSBHostCIEndpointState`](/documentation/IOUSBHost/IOUSBHostCIEndpointStateDestroyed)

[`var IOUSBHostCIEndpointStateHalted: IOUSBHostCIEndpointState`](/documentation/IOUSBHost/IOUSBHostCIEndpointStateHalted)

[`var IOUSBHostCIEndpointStatePaused: IOUSBHostCIEndpointState`](/documentation/IOUSBHost/IOUSBHostCIEndpointStatePaused)

[`var IOUSBHostCIExceptionTypeCapabilitiesInvalid: IOUSBHostCIExceptionType`](/documentation/IOUSBHost/IOUSBHostCIExceptionTypeCapabilitiesInvalid)

[`var IOUSBHostCIExceptionTypeCommandFailure: IOUSBHostCIExceptionType`](/documentation/IOUSBHost/IOUSBHostCIExceptionTypeCommandFailure)

[`var IOUSBHostCIExceptionTypeCommandReadCollision: IOUSBHostCIExceptionType`](/documentation/IOUSBHost/IOUSBHostCIExceptionTypeCommandReadCollision)

[`var IOUSBHostCIExceptionTypeCommandTimeout: IOUSBHostCIExceptionType`](/documentation/IOUSBHost/IOUSBHostCIExceptionTypeCommandTimeout)

[`var IOUSBHostCIExceptionTypeCommandWriteFailed: IOUSBHostCIExceptionType`](/documentation/IOUSBHost/IOUSBHostCIExceptionTypeCommandWriteFailed)

[`var IOUSBHostCIExceptionTypeDoorbellOverflow: IOUSBHostCIExceptionType`](/documentation/IOUSBHost/IOUSBHostCIExceptionTypeDoorbellOverflow)

[`var IOUSBHostCIExceptionTypeDoorbellReadCollision: IOUSBHostCIExceptionType`](/documentation/IOUSBHost/IOUSBHostCIExceptionTypeDoorbellReadCollision)

[`var IOUSBHostCIExceptionTypeFrameUpdateError: IOUSBHostCIExceptionType`](/documentation/IOUSBHost/IOUSBHostCIExceptionTypeFrameUpdateError)

[`var IOUSBHostCIExceptionTypeInterruptInvalid: IOUSBHostCIExceptionType`](/documentation/IOUSBHost/IOUSBHostCIExceptionTypeInterruptInvalid)

[`var IOUSBHostCIExceptionTypeInterruptOverflow: IOUSBHostCIExceptionType`](/documentation/IOUSBHost/IOUSBHostCIExceptionTypeInterruptOverflow)

[`var IOUSBHostCIExceptionTypeProtocolError: IOUSBHostCIExceptionType`](/documentation/IOUSBHost/IOUSBHostCIExceptionTypeProtocolError)

[`var IOUSBHostCIExceptionTypeTerminated: IOUSBHostCIExceptionType`](/documentation/IOUSBHost/IOUSBHostCIExceptionTypeTerminated)

[`var IOUSBHostCIExceptionTypeUnknown: IOUSBHostCIExceptionType`](/documentation/IOUSBHost/IOUSBHostCIExceptionTypeUnknown)

[`var IOUSBHostCILinkStateCompliance: IOUSBHostCILinkState`](/documentation/IOUSBHost/IOUSBHostCILinkStateCompliance)

[`var IOUSBHostCILinkStateDisabled: IOUSBHostCILinkState`](/documentation/IOUSBHost/IOUSBHostCILinkStateDisabled)

[`var IOUSBHostCILinkStateInactive: IOUSBHostCILinkState`](/documentation/IOUSBHost/IOUSBHostCILinkStateInactive)

[`var IOUSBHostCILinkStatePolling: IOUSBHostCILinkState`](/documentation/IOUSBHost/IOUSBHostCILinkStatePolling)

[`var IOUSBHostCILinkStateRecovery: IOUSBHostCILinkState`](/documentation/IOUSBHost/IOUSBHostCILinkStateRecovery)

[`var IOUSBHostCILinkStateReset: IOUSBHostCILinkState`](/documentation/IOUSBHost/IOUSBHostCILinkStateReset)

[`var IOUSBHostCILinkStateResume: IOUSBHostCILinkState`](/documentation/IOUSBHost/IOUSBHostCILinkStateResume)

[`var IOUSBHostCILinkStateRxDetect: IOUSBHostCILinkState`](/documentation/IOUSBHost/IOUSBHostCILinkStateRxDetect)

[`var IOUSBHostCILinkStateTest: IOUSBHostCILinkState`](/documentation/IOUSBHost/IOUSBHostCILinkStateTest)

[`var IOUSBHostCILinkStateU0: IOUSBHostCILinkState`](/documentation/IOUSBHost/IOUSBHostCILinkStateU0)

[`var IOUSBHostCILinkStateU1: IOUSBHostCILinkState`](/documentation/IOUSBHost/IOUSBHostCILinkStateU1)

[`var IOUSBHostCILinkStateU2: IOUSBHostCILinkState`](/documentation/IOUSBHost/IOUSBHostCILinkStateU2)

[`var IOUSBHostCILinkStateU3: IOUSBHostCILinkState`](/documentation/IOUSBHost/IOUSBHostCILinkStateU3)

[`var IOUSBHostCIMessageStatusBadArgument: IOUSBHostCIMessageStatus`](/documentation/IOUSBHost/IOUSBHostCIMessageStatusBadArgument)

[`var IOUSBHostCIMessageStatusEndpointStopped: IOUSBHostCIMessageStatus`](/documentation/IOUSBHost/IOUSBHostCIMessageStatusEndpointStopped)

[`var IOUSBHostCIMessageStatusError: IOUSBHostCIMessageStatus`](/documentation/IOUSBHost/IOUSBHostCIMessageStatusError)

[`var IOUSBHostCIMessageStatusMissedServiceError: IOUSBHostCIMessageStatus`](/documentation/IOUSBHost/IOUSBHostCIMessageStatusMissedServiceError)

[`var IOUSBHostCIMessageStatusNoResources: IOUSBHostCIMessageStatus`](/documentation/IOUSBHost/IOUSBHostCIMessageStatusNoResources)

[`var IOUSBHostCIMessageStatusNotPermitted: IOUSBHostCIMessageStatus`](/documentation/IOUSBHost/IOUSBHostCIMessageStatusNotPermitted)

[`var IOUSBHostCIMessageStatusOffline: IOUSBHostCIMessageStatus`](/documentation/IOUSBHost/IOUSBHostCIMessageStatusOffline)

[`var IOUSBHostCIMessageStatusOverrunError: IOUSBHostCIMessageStatus`](/documentation/IOUSBHost/IOUSBHostCIMessageStatusOverrunError)

[`var IOUSBHostCIMessageStatusProtocolError: IOUSBHostCIMessageStatus`](/documentation/IOUSBHost/IOUSBHostCIMessageStatusProtocolError)

[`var IOUSBHostCIMessageStatusReserved: IOUSBHostCIMessageStatus`](/documentation/IOUSBHost/IOUSBHostCIMessageStatusReserved)

[`var IOUSBHostCIMessageStatusStallError: IOUSBHostCIMessageStatus`](/documentation/IOUSBHost/IOUSBHostCIMessageStatusStallError)

[`var IOUSBHostCIMessageStatusSuccess: IOUSBHostCIMessageStatus`](/documentation/IOUSBHost/IOUSBHostCIMessageStatusSuccess)

[`var IOUSBHostCIMessageStatusTimeout: IOUSBHostCIMessageStatus`](/documentation/IOUSBHost/IOUSBHostCIMessageStatusTimeout)

[`var IOUSBHostCIMessageStatusTransactionError: IOUSBHostCIMessageStatus`](/documentation/IOUSBHost/IOUSBHostCIMessageStatusTransactionError)

[`var IOUSBHostCIMessageTypeCommandMax: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeCommandMax)

[`var IOUSBHostCIMessageTypeCommandMin: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeCommandMin)

[`var IOUSBHostCIMessageTypeControllerCapabilities: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeControllerCapabilities)

[`var IOUSBHostCIMessageTypeControllerFrameNumber: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeControllerFrameNumber)

[`var IOUSBHostCIMessageTypeControllerPause: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeControllerPause)

[`var IOUSBHostCIMessageTypeControllerPowerOff: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeControllerPowerOff)

[`var IOUSBHostCIMessageTypeControllerPowerOn: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeControllerPowerOn)

[`var IOUSBHostCIMessageTypeControllerStart: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeControllerStart)

[`var IOUSBHostCIMessageTypeDeviceCreate: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeDeviceCreate)

[`var IOUSBHostCIMessageTypeDeviceDestroy: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeDeviceDestroy)

[`var IOUSBHostCIMessageTypeDevicePause: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeDevicePause)

[`var IOUSBHostCIMessageTypeDeviceStart: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeDeviceStart)

[`var IOUSBHostCIMessageTypeDeviceUpdate: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeDeviceUpdate)

[`var IOUSBHostCIMessageTypeEndpointCreate: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeEndpointCreate)

[`var IOUSBHostCIMessageTypeEndpointDestroy: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeEndpointDestroy)

[`var IOUSBHostCIMessageTypeEndpointPause: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeEndpointPause)

[`var IOUSBHostCIMessageTypeEndpointReset: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeEndpointReset)

[`var IOUSBHostCIMessageTypeEndpointSetNextTransfer: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeEndpointSetNextTransfer)

[`var IOUSBHostCIMessageTypeEndpointUpdate: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeEndpointUpdate)

[`var IOUSBHostCIMessageTypeEndpoint_reserved_: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeEndpoint_reserved_)

[`var IOUSBHostCIMessageTypeFrameNumberUpdate: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeFrameNumberUpdate)

[`var IOUSBHostCIMessageTypeFrameTimestampUpdate: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeFrameTimestampUpdate)

[`var IOUSBHostCIMessageTypeIsochronousTransfer: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeIsochronousTransfer)

[`var IOUSBHostCIMessageTypeLink: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeLink)

[`var IOUSBHostCIMessageTypeNormalTransfer: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeNormalTransfer)

[`var IOUSBHostCIMessageTypePortCapabilities: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypePortCapabilities)

[`var IOUSBHostCIMessageTypePortDisable: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypePortDisable)

[`var IOUSBHostCIMessageTypePortEvent: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypePortEvent)

[`var IOUSBHostCIMessageTypePortPowerOff: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypePortPowerOff)

[`var IOUSBHostCIMessageTypePortPowerOn: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypePortPowerOn)

[`var IOUSBHostCIMessageTypePortReset: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypePortReset)

[`var IOUSBHostCIMessageTypePortResume: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypePortResume)

[`var IOUSBHostCIMessageTypePortStatus: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypePortStatus)

[`var IOUSBHostCIMessageTypePortSuspend: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypePortSuspend)

[`var IOUSBHostCIMessageTypeSetupTransfer: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeSetupTransfer)

[`var IOUSBHostCIMessageTypeStatusTransfer: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeStatusTransfer)

[`var IOUSBHostCIMessageTypeTransferComplete: IOUSBHostCIMessageType`](/documentation/IOUSBHost/IOUSBHostCIMessageTypeTransferComplete)

[`var IOUSBHostCIPortStateActive: IOUSBHostCIPortState`](/documentation/IOUSBHost/IOUSBHostCIPortStateActive)

[`var IOUSBHostCIPortStateOff: IOUSBHostCIPortState`](/documentation/IOUSBHost/IOUSBHostCIPortStateOff)

[`var IOUSBHostCIPortStatePowered: IOUSBHostCIPortState`](/documentation/IOUSBHost/IOUSBHostCIPortStatePowered)

[`var IOUSBHostCIPortStateSuspended: IOUSBHostCIPortState`](/documentation/IOUSBHost/IOUSBHostCIPortStateSuspended)

[`var IOUSBHostCIUserClientVersion100: IOUSBHostCIUserClientVersion`](/documentation/IOUSBHost/IOUSBHostCIUserClientVersion100)


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