Interval Property

项目
09/21/2010

The Interval property gets or sets the bInterval field of the endpoint descriptor, as described in section 9.6.6 of the USB 2.0 specification.

This property is read/write.

Syntax

HRESULT put_Interval(
  [in]           BYTE bInterval
);

HRESULT get_Interval(
  [out, retval]  BYTE *pbInterval
);

Property Value

The new value for the endpoint interval.

Error Codes

Interval returns S_OK if the operation succeeds or E_POINTER if the pbInterval parameter is not a valid pointer.

Remarks

The following C++ code example shows to set and get the Interval property.

HRESULT CLoopBackDevice::UpdateInterval(ISoftUSBEndpoint *piEndpoint)
{
HRESULT hr = S_OK;
BYTE   bInterval = 0;
BYTE   bNewInterval = 0;

 if(NULL == piEndpoint)
{
 hr = E_INVALIDARG;
 goto Exit;
}

// Get the current endpoint interval
 hr = piEndpoint->get_Interval (&bInterval);
 if(FAILED(hr))
 goto Exit;

// Update the endpoint interval if required
 if (bNewInterval != bInterval)
{
 hr = piEndpoint->put_Interval (bNewInterval);
 if(FAILED(hr))
 goto Exit;
}
Exit:
 return hr;
}

Requirements

Header

SoftUSBif.h

通过