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# frameNumberWithTime:

Returns the current frame number of the USB controller.

```
- (uint64_t) frameNumberWithTime:(IOUSBHostTime *) time;
```

## Parameters

`time`

An [`IOUSBHostTime`](/documentation/IOUSBHost/IOUSBHostTime) reference. If not `nil`, this updates with the current system time.

## Return Value

The current frame number.

## Discussion

This method returns the current frame number of the USB controller, omitting the microframe. This is useful for scheduling future isochronous requests with [`enqueueIORequest(with:frameList:frameListCount:firstFrameNumber:completionHandler:)`](/documentation/IOUSBHost/IOUSBHostPipe/enqueueIORequest(with:frameList:frameListCount:firstFrameNumber:completionHandler:)) and [`sendIORequest(with:frameList:frameListCount:firstFrameNumber:)`](/documentation/IOUSBHost/IOUSBHostPipe/sendIORequest(with:frameList:frameListCount:firstFrameNumber:)).

---

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