Hallo,
I would understand about writing single sample at high rate as 20ns (the rate of NI-6733 Analog Output Module).
I write this code in CVI:
#include <cvirte.h>
#include "cvidll.h"
#include <userint.h>
#include <ansi_c.h>
#include <math.h>
#include "nidaqmx.h"
#include <stdio.h>
static int init=0;
int __stdcall DllMain (HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpvReserved)
{
switch (fdwReason)
{
case DLL_PROCESS_ATTACH:
/* Respond to DLL loading by initializing the RTE */
if (InitCVIRTE (hinstDLL, 0, 0) == 0)
return 0;
break;
case DLL_PROCESS_DETACH:
/* Respond to DLL unloading by closing the RTE for its use */
if (!CVIRTEHasBeenDetached ())
CloseCVIRTE ();
break;
}
/* Return 1 to indicate successful initialization */
return 1;
}
int __stdcall DLLfunc3 (int voltage)
{
int Err_output=1;
int TuttoOk=0;
int i=0;
float64 data[1000];
float64 voltaggio;
TaskHandle mytaskHandle=0;
/* Creazione del task */
Err_output = DAQmxCreateTask("",&mytaskHandle);
if(Err_output==0)
{
TuttoOk++;
/*for(;i<1000;i++)
data[i] = 1*sin((double)i*2.0*3.14/1000.0);*/
Err_output = DAQmxCreateAOVoltageChan(mytaskHandle,"PXI1Slot4/ao0","",
-10,10,DAQmx_Val_Volts,"");
if(Err_output==0)
{
TuttoOk=TuttoOk+10;
}
/*Err_output = DAQmxStartTask(mytaskHandle);
if(Err_output==0)
{
TuttoOk=TuttoOk+100;
}*/
Err_output = DAQmxWriteAnalogScalarF64(mytaskHandle, 1, 0.0, voltage, NULL);
if(Err_output==0)
{
TuttoOk=TuttoOk+1000;
}
}
return Err_output;
}
Then create Debuggable DLL for real time target, I call created DLL in deterministic loop in Real-Time project (LabView).
There are some problem:
- DAQmxStartTask(mytaskHandle);
probably is incorrect! why?
- DAQmxWriteAnalogScalarF64(mytaskHandle, 1, 0.0, voltage, NULL);
probably is incorrect! why?
- Can I write a single sample at rate of 20ns? Can I fully use the hardware performance? How make this?
I desire generate a single sample at high rate for control of sound where it is necessary high frequency!!!
Thanks for help in advance. Michael
