//===================================================================================================
/// <summary>
/// Creates one or more BulkInRequest objects that contain the overlapped struct and data buffer
/// These are used by the SubmitBulkInRequest and CompleteBulkInRequest methods
/// </summary>
//===================================================================================================
protected override void CreateBulkInputRequestObjects(int transferSize)
{
m_bulkInRequests.Clear();
int byteRatio = m_criticalParams.DataInXferSize;
int channelCount = m_criticalParams.AiChannelCount;
for (int i = 0; i < m_numberOfWorkingInputRequests; i++)
{
UsbBulkInRequest request = new UsbBulkInRequest();
request.Index = i;
request.Overlapped = new Overlapped();
if (m_criticalParams.InputTransferMode == TransferMode.SingleIO)
{
request.Buffer = new byte[byteRatio * channelCount];
if (m_criticalParams.NumberOfSamplesForSingleIO > 1)
{
// use n bytes per channel...
request.BytesRequested = byteRatio * channelCount;
}
else
{
// only n bytes per transfer regardless of channel count...
request.BytesRequested = byteRatio;
}
}
else
{
request.Buffer = new byte[transferSize];
request.BytesRequested = request.Buffer.Length;
}
request.NativeOverlapped = request.Overlapped.Pack(CompleteBulkInRequest, request.Buffer);
if (sizeof(IntPtr) == 8)
request.NativeOverLappedIntPtr = new IntPtr((long)request.NativeOverlapped);
else
request.NativeOverLappedIntPtr = new IntPtr((int)request.NativeOverlapped);
if (i > 0)
m_bulkInRequests[i - 1].Next = request;
m_bulkInRequests.Add(request);
}
m_bulkInRequests[m_bulkInRequests.Count - 1].Next = m_bulkInRequests[0];
}
//===================================================================================================
/// <summary>
/// Sumbimits one or more read pipe requests using overlapped I/O
/// The I/O completion callback is handled by CompleteBulkInRequest
/// </summary>
/// <param name="request">A UsbBulkInRequest object</param>
/// <returns>The result of the read pipe method</returns>
//===================================================================================================
protected bool SubmitBulkInRequest(UsbBulkInRequest request)
{
bool result;
uint lengthTransfered = 0;
if (m_deviceInfo.EndPointIn == 0)
{
m_inputScanErrorCode = ErrorCodes.BulkInputTransfersNotSupported;
return false;
}
if (m_criticalParams.InputSampleMode == SampleMode.Finite)
{
// for finite mode, the number of bytes in the last transfer may need to be reduced so that the
// number of bytes transfered equals the number of bytes requested
if (m_totalNumberOfInputBytesTransferred + request.BytesRequested > m_totalNumberOfInputBytesRequested)
{
request.BytesRequested = (m_totalNumberOfInputBytesRequested - m_totalNumberOfInputBytesTransferred);
}
}
m_totalNumberOfInputBytesTransferred += request.BytesRequested;
//DebugLogger.WriteLine("Submitting bulk in index# {0}, request# {1} ", request.Index, request.RequestNumber);
result = McUsb_ReadPipe(m_deviceHandle,
m_deviceInfo.EndPointIn,
request.Buffer,
(uint)request.BytesRequested,
ref lengthTransfered,
request.NativeOverLappedIntPtr);
// store this request object so we know which one to submit next
m_lastInputRequestSubmitted = request;
// increment number of requests submitted
m_numberOfInputRequestsSubmitted++;
// for continuous mode keep incrementing the total number of requests
if (m_criticalParams.InputSampleMode == SampleMode.Continuous)
{
m_totalNumberOfInputRequests++;
if (m_totalNumberOfInputRequests < 0)
{
m_numberOfInputRequestsSubmitted = 0;
m_totalNumberOfInputRequests = m_numberOfInputRequestsSubmitted + 1;
}
}
if (!result)
{
int errorCode = GetLastError();
// error 997 is Overlapped I/O operation is in progress (so this is good).
if (errorCode == 997)
{
m_inputScanErrorCode = ErrorCodes.NoErrors;
result = true;
}
else
{
m_inputScanErrorCode = ErrorCodes.UnknownError;
}
}
return result;
}
//===================================================================================================
/// <summary>
/// Creates one or more BulkInRequest objects that contain the overlapped struct and data buffer
/// These are used by the SubmitBulkInRequest and CompleteBulkInRequest methods
/// </summary>
//===================================================================================================
protected override void CreateBulkInRequestObjects()
{
m_bulkInRequests.Clear();
for (int i = 0; i < m_numberOfWorkingInputRequests; i++)
{
// create bulk in request object
UsbBulkInRequest request = new UsbBulkInRequest();
// assign index
request.Index = i;
// allocate the bulk in request buffer
request.Buffer = new byte[m_bulkInXferSize];
request.BytesRequested = request.Buffer.Length;
m_bulkInRequests.Add(request);
}
}