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# MIDICIResponder

An object that responds to MIDI-CI inquiries from an initiator on behalf of a MIDI client, and handles profile and property exchange operations.

```
class MIDICIResponder
```

## Topics

### Creating a Responder

[`init(deviceInfo:profileDelegate:profileStates:supportProperties:)`](/documentation/CoreMIDI/MIDICIResponder/init(deviceInfo:profileDelegate:profileStates:supportProperties:))

Creates a new responder.

### Managing the Life Cycle

[`start()`](/documentation/CoreMIDI/MIDICIResponder/start())

Starts receiving initiator requests.

[`stop()`](/documentation/CoreMIDI/MIDICIResponder/stop())

Stops receiving initiator requests and disconnects all connected initiators.

### Setting a Responder Delegate

[`profileDelegate`](/documentation/CoreMIDI/MIDICIResponder/profileDelegate)

The profile delegate.

[`MIDICIProfileResponderDelegate`](/documentation/CoreMIDI/MIDICIProfileResponderDelegate)

A protocol that defines the methods to respond to MIDI-CI responder life-cycle events.

### Inspecting a Responder

[`MIDICIInitiatiorMUID`](/documentation/CoreMIDI/MIDICIInitiatiorMUID)

The unique MIDI-CI negotiation identifier to use for a responder connection.

[`initiators`](/documentation/CoreMIDI/MIDICIResponder/initiators)

An array of initiators.

[`MIDICIDeviceIdentification`](/documentation/CoreMIDI/MIDICIDeviceIdentification)

A structure that describes a MIDI-CI device.

[`MIDICIDeviceInfo`](/documentation/CoreMIDI/MIDICIDeviceInfo)

An object that provides basic information about a MIDI-CI device.

[`deviceInfo`](/documentation/CoreMIDI/MIDICIResponder/deviceInfo)

The MIDI-CI device’s information.

### Broadcasting Profile Changes

[`notify(_:onChannel:isEnabled:)`](/documentation/CoreMIDI/MIDICIResponder/notify(_:onChannel:isEnabled:))

Enables or disables a profile and notifies all connected initiators.

[`send(_:onChannel:profileData:)`](/documentation/CoreMIDI/MIDICIResponder/send(_:onChannel:profileData:))

Sends profile-specific data to all connected initiators.


---

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