I wrote simple code, wich uses Bulk transfer.

Now it makes out transfer, and after transfers in, using the standart bulkloop.hex.

Made it on C++, used thread:

//---------------------------------------------------------------------------

class WriteAndReadThread : public TThread

{

private:

         void __fastcall Printing();

protected:

        void __fastcall Execute();    

public:

        __fastcall WriteAndReadThread(bool CreateSuspended); 

};

//---------------------------------------------------------------------------

WriteAndReadThread *writereader;  

//---------------------------------------------------------------------------

//конструктор потока WriteAndReadThread, по умолчанию пустой

__fastcall WriteAndReadThread::WriteAndReadThread(bool CreateSuspended) : TThread(CreateSuspended)

{}

//---------------------------------------------------------------------------

void __fastcall WriteAndReadThread::Execute()

{

 AnsiString stryng = Form1->Edit1->Text.c_str();

 outBuf=new char[stryng.Length()+1];

 strcpy(outBuf,stryng.c_str());

 length = stryng.Length()+1;

 //length = strlen(buffer);

 while(!Terminated)

  {

   outOvLap.hEvent = CreateEvent(NULL, false, false, "CYUSB_OUT");

   UCHAR *outContext;

   outContext = USBDevice->BulkOutEndPt->BeginDataXfer(outBuf, length, &outOvLap);   

   USBDevice->BulkOutEndPt->WaitForXfer(&outOvLap,100);            

   succesOut = USBDevice->BulkOutEndPt->FinishDataXfer(outBuf, length, &outOvLap,outContext); 

   if(!succesOut)

    {

     writereader->Terminate();         

     if(drawer)drawer->Terminate();

     Form1->SpeedButton1->Caption = "Begin transfer";

     Form1->SpeedButton1->Down = false;

     Form1->Memo1->Lines->Add("Sending error!");

    }

   CloseHandle(outOvLap.hEvent);

   inOvLap.hEvent = CreateEvent(NULL, false, false, "CYUSB_IN");

   UCHAR *inContext = USBDevice->BulkInEndPt->BeginDataXfer(inBuf, length, &inOvLap);

   USBDevice->BulkInEndPt->WaitForXfer(&inOvLap,100);

   succesIn = USBDevice->BulkInEndPt->FinishDataXfer(inBuf, length, &inOvLap,inContext); 

   if(!succesIn)  

    {

     writereader->Terminate();       

     if(drawer)drawer->Terminate();

     Form1->SpeedButton1->Caption = "Begin transfer";

     Form1->SpeedButton1->Down = false;

     Form1->Memo1->Lines->Add("Recieving error!");

    }

   Synchronize(Printing);

   CloseHandle(inOvLap.hEvent);

  }

The speed for in transfer is realy slow.  If I'll make the only IN transfer it will be not higther than 1 Mbyte per second.

Using the CyAPI how can I make with the speed 12 Mbyte per sec?

Is the device connected as a full speed or high speed device?
Have you tried using streamer to measure the speed i.e. start one streamer stream to the out endpoint then start another streamer are receive from the IN endpoint?
Regards,
Anand