I am using the spectrum digital USB example code to interface the tms320c5509a with
labVIEW.  Currently I can do a VISA write from labVIEW and a VISA read with everything working
correctly (everything being excited inside the USB_bulkOutEvHandler).

What I would like to do is a VISA read, without first doing a VISA write.  I have been trying
to achieve this by having the DSP program call the USB_bulkInEvHandler which posts a
transaction and then doing a VISA read from labview but it does not seem to be working. It
seems like my approach is skipping the USB_evDispatch so it might not be setting up the USB
flags correctly??   

There is also the commented section in the example code about using a SWI which might contain
the answer but I do not know how to use it.  Any help/example code would be greatly
appreciated.  

Here is the code.  

void USB_bulkOutEvHandler()
{
  // call the bulk out data handler routine.
  
  // if DSP/BIOS used, a SWI can be posted to service the endpoint events.
  // All USB event handler routines must be executed in the order the 
  // actual events arrived - to achieve this, if SWI used, all the USB 
  // event handler routines must be assigned the same priority level.
  
  USB_bulkOutDatHandler(&usbEpObjIn2, &usbEpObjOut2);
}
void USB_bulkOutDatHandler(USB_EpHandle hEpIn, USB_EpHandle hEpOut)
{
	
// loop back data received from endpt2 out to endpt2 in
   if(USB_isTransactionDone(hEpOut))  
	
     if(Endpt2Buff[1]==0x6161)
       {
         USB_postTransaction(hEpIn, 10, &usb_dataTest, USB_IOFLAG_NOSHORT);                
     
       }
     else if (Endpt2Buff[1]==0x6262)
       {
       USB_postTransaction(hEpIn, 1024, output_buf_1K, USB_IOFLAG_NOSHORT);                    
 
       }
}

/*******************************************************************/
/*                      Bulk In Event Handlers                                                 
                                    */
/*******************************************************************/
void USB_bulkInEvHandler()
{
  // call the bulk in data handler routine.
  
  // if DSP/BIOS used, a SWI can be posted to service the endpoint events.
  // All USB event handler routines must be executed in the order the 
  // actual events arrived - to achieve this, if SWI used, all the USB 
  // event handler routines must be assigned the same priority level.
  
  USB_bulkInDatHandler(&usbEpObjIn2, &usbEpObjOut2);
}
void USB_bulkInDatHandler(USB_EpHandle hEpIn, USB_EpHandle hEpOut)
  {  
   
   if(USB_isTransactionDone(hEpIn))
     {
      // initiate packet read from endpt2 out - up to 64 bytes 
         USB_postTransaction(hEpOut, 10, &usb_dataTest, USB_IOFLAG_NOSHORT);               
      
      }     
                 
}

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