how can i specify data lenght received by CANcaseXL from Vector

have some seriouse probleme with defining the data lenght of my received message obtained directly from CanCase, i know that my received msg will contain a data lenght of 20 byte but the program that i have writ accept only 8 byte as received data.


/// ******************************************************************
/// <summary>
/// RX_Thread
///
/// Description:
/// Second thread which receives data from configured receive port
/// (CANDemo_RxChannel)of XL interface.
/// </summary>
/// ******************************************************************
#region EVENT THREAD (RX)
public void RX_Thread()
{
// object to be fill with received data
XLClass.xl_event receivedEvent = new XLClass.xl_event();
// result of XL driver func. calls
XLClass.XLstatus xlStatus = XLClass.XLstatus.XL_SUCCESS;
// WaitForSingleObject values
WaitResults waitResult = new WaitResults();


// note: this thread is destroyed by MAIN
while (true)
{
// wait for hardware events
waitResult = (WaitResults)WaitForSingleObject(CANDemo_RxChannel.eventHandle, 1000);

// if event occured...
if (waitResult != WaitResults.WAIT_TIMEOUT)
{
// ...init xlStatus first
xlStatus = XLClass.XLstatus.XL_SUCCESS;

// afterwards: while hw queue is not empty...
while (xlStatus != XLClass.XLstatus.XL_ERR_QUEUE_IS_EMPTY)
{
// ...receivedata from hardware queue
xlStatus = CANDemo_RxChannel.xlReceive(ref receivedEvent);

// if receiveing succeed...
if (xlStatus == XLClass.XLstatus.XL_SUCCESS)
{
// filter various messages

{
// ...print rx data
CANDemo.XL_GetEventString(receivedEvent);
if (receivedEvent.tagData.can_Msg.id == 0x76D)
{
//Diagnostic mode of USM-CMF
if (receivedEvent.tagData.can_Msg.data[0] == Convert.ToByte(2) && receivedEvent.tagData.can_Msg.data[1] == Convert.ToByte(80) && receivedEvent.tagData.can_Msg.data[2] == Convert.ToByte(250))

{
StopRxThread(CANDemo.XL_GetEventString(receivedEvent));
}
//Serial Number of USM-CMF
if (receivedEvent.tagData.can_Msg.data[0] == Convert.ToByte(16) && receivedEvent.tagData.can_Msg.data[1] == Convert.ToByte(22) && receivedEvent.tagData.can_Msg.data[2] == Convert.ToByte(97))
{
StopRxThread(CANDemo.XL_GetEventString(receivedEvent));
}
}
}
}
}
}
// no event occured
}
}
#endregion
/// ------------------------------------------------------------------



how can i set the property o receiving the message as 20 bytes or whatever lenght i want ?

thanks a lot in advance

- - - Updated - - -

its like receiving a multi can response in the same time that have all the same ID but with different info–