frameNumberWithTime:
Returns the current frame number of the USB controller.
Declaration
- (uint64_t) frameNumberWithTime:(IOUSBHostTime *) time;Parameters
- time:
An 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:) and sendIORequest(with:frameList:frameListCount:firstFrameNumber:).