<!--
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  "documentType" : "symbol",
  "framework" : "USBDriverKit",
  "identifier" : "/documentation/USBDriverKit/IOUSBHostInterface/ReferenceMicroframe",
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  "title" : "ReferenceMicroframe"
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# ReferenceMicroframe

```
virtual kern_return_t ReferenceMicroframe(uint64_t *microframeNumber, uint64_t *theTime);
```

## Parameters

`microframeNumber`

uint64_t pointer to be updated with the current frame number

`theTime`

If not NULL, this will be updated with the system time assosiated with the returned microframe

## Return Value

KERN_SUCCESS is successful see IOReturn.h for error codes.

## Discussion\abstract Return a recent microframe number of the USB controller.
\discussion This method will return a recent microframe number of the USB controller
with a timestamp captured near the microframe boundary.
This is most useful for scheduling future isochronous requests.

---

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