MaxPacketSize Property
The MaxPacketSize property gets or sets the wMaxPacketSize 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_MaxPacketSize(
[in] SHORT sMaxPacketSize
);
HRESULT get_MaxPacketSize(
[out, retval] SHORT *psMaxPacket
);
Property Value
The new maximum packet size for the endpoint.
Error Codes
MaxPacketSize returns S_OK if the operation succeeds or E_POINTER if the psMaxPacket parameter is not a valid pointer.
Remarks
The following C++ code example shows how to set and get the MaxPacketSize property.
HRESULT CLoopBackDevice::UpdateEndpointMaxPacketSize(ISoftUSBEndpoint *piEndpoint)
{
HRESULT hr = S_OK;
SHORT sMaxPacketSize = 0;
SHORT sNewMaxPacketSize = 1024;
if(NULL == piEndpoint)
{
hr = E_INVALIDARG;
goto Exit;
}
// Get the current MaxPacketSize property
hr = piEndpoint->get_MaxPacketSize (&sMaxPacketSize);
if(FAILED(hr))
goto Exit;
// Update the MaxPacketSize if required
if (sNewMaxPacketSize != sMaxPacketSize)
{
hr = piEndpoint->put_MaxPacketSize(sNewMaxPacketSize);
if(FAILED(hr))
goto Exit;
}
Exit:
return hr;
}
Requirements
Header |
SoftUSBif.h |
See Also
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Build date: 9/21/2010