Problems with the ag2k3k driver

[mkossmann]

We are trying to use the ag2k3k IVI driver to control a DSO-X 3034A. ( with latest firmware V2.20)

There are two major problems when using that driver.

The driver uses :DIG to start acquisitions for measurements.

That's fine if the signal fulfills the trigger conditions, which were setup before. But we have have to measure a signal from a possibly defective DUT. So we cannot guarantee that the trigger condition is fulfilled. In that case, Agilents documentation (programming guide chapter "Aquiring a waveform",attached) states, that you have to do a  "device clear" to clean up/stop the aquisition properly. Otherwise the remote interface may timeout. To demonstrate what this means  I've attached an IO-Trace log ( just sending a :DIG and a :STOP a a few *IDN? with the VISA test panel) The driver neither does that clean up by doing a viClear() internally nor does it provide a VI to do that manually.

If you are using  the lowlevel aquistion functions there is no VI to decide if an aquisition has finished.

There is agx2k3k_AcquisitionStatus(). This returns 1 if :ACQ:COND? returns 100. And does it allways because you can set  :ACQ:COND only to 100 according to the scopes documentation. So it is quie useless. You have to do something like an *OPC? query instead. Maybe provide a VI for the internally used agx2k3k_WaitForOPC() function

The driver nsource identifies itself as :

/********************************************************************************
 *  Copyright 2011-2012, National Instruments, Corporation.  All Rights Reserved.    *
 ********************************************************************************/
/*****************************************************************************
 *  Agilent 2000 and 3000 X-Series Oscilloscopes Instrument Driver
 *  LabWindows/CVI Instrument Driver
 *  Original Release: 24. June 2011
 *  By: Chenchen Zhou, National Instruments
 *
 *  Modification History:
 *
 *  2011-06-24 - Instrument Driver Created.
 *  2011-12-05 - [czhou] Update the error checking code in
 *                       agx2k3k_ReadWaveformMeasurement function.
 *  2012-09-01 - [hfeng] Add support for new models:MSO-X 3102A, MSO-X 3104A,
 *                       DSO-X 3102A, DSO-X 3104A
 *                       New functionality in power group, search group, demo
 *                       group, trigger group, function group, Serial Bus group,
 *                       marker group, WGEN group
 *****************************************************************************/

[naphelly24]

Hi mkossmann,

For your first problem, actually NI driver provides a "Abort.vi" to stop the aquisition. You can use this VI to stop the aquisition manually.

As for your second problem, you are right about agx2k3k_AcquisitionStatus() function, it's useless to decide if an aquisition has finished. We need to use *OPC instead.

NI will release an update driver about ag2k3k in 2 or 3 weeks which provides a *OPC query VI as you suggested. You can use the new driver by then.

[naphelly24]

Hi mkossmann,

I may misunderstanded your first problem.

It's not ":STOP" but "viClear()" that this IVI driver lacks, is this what you meant?

[mkossmann]

The Abort VI  sends a  :STOP to the device. According to Agilents documentation, that stops an acquisition started  with :RUN, but if you use :DIG to start the  acquisition you will need a "device clear". ( Quote from programmers guide: "To halt a :DIGitize in progress, use the device clear command")

The attached log ( Timeout.zip in my first message)  from NI IO-Trace clearly demonstrates that problem. The first *IDN? shows that communication is working, Then a :DIG ( without trigger condition) and a :STOP.

After that even a *IDN? query doesn't work any more. Only doing a device clear with viClear() revives the instrument.   

Suggesting OPC for solving the second problem was wrong.  That also returns  1 if the aquisition is not started/triggered.

Querying Bit 3 of  Operation Status Condition Register is the documented thing to do. However it doesn't seem to work when :DIG is used to start the aquisition. Then the this query just times out.  Don't know if that has to be considered as a firmware bug .

PS:just read your second post: Yes, you misunderstood me.

[mkossmann]

This is a reimplementation for agx2k3k_AcquisitionStatus() querying bit 3 of OPER:COND as suggested in Agilents documentation. This works for me, if the scope was set to single trigger mode before with agx2k3k_ConfigureInitiateContinuous (Handle_SCOPE, VI_FALSE);

ViStatus _VI_FUNC agx2k3k_AcquisitionStatus (ViSession vi,
                                              ViInt32 *statusRef)
{
    ViStatus    error = VI_SUCCESS;
    ViInt32     status = AGX2K3K_VAL_ACQ_STATUS_UNKNOWN;

    checkErr( Ivi_LockSession (vi, VI_NULL));

    if (statusRef == VI_NULL)
            viCheckParm( IVI_ERROR_INVALID_PARAMETER, 2, "Null address for Status");

    if (!Ivi_Simulating (vi))                // call only when locked
    {
        ViSession   io = Ivi_IOSession (vi); // call only when locked
        ViInt32     state = 0;
        checkErr( Ivi_SetNeedToCheckStatus (vi, VI_TRUE));

        viCheckErr( viQueryf (io, ":OPER:COND?", "%d", &state));

        if ((state & 0x8) == 0x8 )   // Running bit set
            status = AGX2K3K_VAL_ACQ_IN_PROGRESS;
        else
            status = AGX2K3K_VAL_ACQ_COMPLETE;
    }
    else
    {
        status = AGX2K3K_VAL_ACQ_COMPLETE;
    }

Error:
    *statusRef = status;
    Ivi_UnlockSession (vi, VI_NULL);
    return error;
}

[naphelly24]

Seems the instrument won't respond to any command after DIG is sent. We'll check this issue with Agilent ASAP.

Regard to the first problem, NI will provide a viClear() interface in the next update driver.

[naphelly24]

Got answer from agilent. Actually we could know whether an acquisition has been finished.

The first way is to query *OPC? with a long enough timeout for the :DIG operation to complete. But I think this method is not what you want.

The second method is to use viReadSTB():

Send:

*ESE 1 – Mask the Standard Event Register output to send only the OPC bit to the Status Byte Register.

*CLS – Clear the status model

:DIG

*OPC – Set the OPC bit in the Event Status Register when the digitize is done.

Use viReadSTB() to read the Status Byte Register, if bit 5 in the Status Byte Register goes true, the acquisition is finished.