PCI-6110: How to access AI Hold Complete?

[EricHo]

Hello,

I have an S-Series PCI-6110. Using Traditional NI-DAQ, we are able to export SCANCLK to a BNC-2110. However, I can't seem to find a way to export the equivalent signal in NI-DAQmx (AIHoldCompleteEvent).

I'm using MeasurementStudio 2005 NET with C#. Attempted the following command

acqTask.ExportSignals.ExportHardwareSignal(ExportSignal.AIHoldCompleteEvent, "AI HOLD COMP");

The same line of code worked when exporting the TRIG1 and SampleClock signals to PFI0 and PFI7.

Pls help, thank you.

Rgds, Eric

[Paul_C.]

Hey Eric,

The scan clock in traditional DAQ is just the sample clock in DAQmx.  So, you should be doing the same thing by exporting the sample clock.  Please let me know if there is something I'm missing.  If you are looking to export the AI Hold Complete Event, you have to set the terminal in an attribute.  This is explained in the knowledgebase here.

I hope this helps,
Paul C.

[EricHo]

Hi Paul,

Thanks for the link. I'll try fiddling around with creating an Event on the acquisition task to output AI Hold Complete Event to a terminal... or something like that 😞  (Its not clear how to do this with code on C# .NET platform).

Some more details, in case it gives rise to new suggestions for me to try:

There are 2 internally generated periodic signals that I intend to use. Under Traditional NIDAQ terminology, the signals are called STARTSCAN (sample clock that indicates the beginning of a new acquisition... looks like one cycle before the CONVERT signal) and SCANCLK (a signal after each acquisition is completed). In my application, SCANCLK and STARTSCAN are derived from the same 20Mhz timebase but phase shifted around the actual analog-to-digital acquisition of samples.

The document below suggests the new names of these signals. There is no STARTSCAN listed (although this signal name is present in the 2002 PCI-6110 user manual   http://www.ni.com/pdf/manuals/321759d.pdf ) and the closest equivalent names I found are

 http://digital.ni.com/public.nsf/allkb/7759B0D2A8A392DF86256D21001B452E

Trad NIDAQ => NI-DAQmx

Scan Clock =>  Sample Clock

SCANCLK   => AI Hold Complete Event

Thanks again.

Rgds, Eric

[Steve_B]

Hi Eric,

Paul's recommendation and your terminology conversion is correct. You will be wanting to use the Sample Clock and the AI Hold Complete Event. 

The .NET help lists the property to set as:

[C#]

public string AIHoldCompleteEventOutputTerminal {get; set;}

You will be able to set this property once and the hardware will export the signal to the pin you designate. If you want to find more references for using the DAQmx driver in .NET you can refer to the KnowledgeBase below to find the help. 

Locations for the NI-DAQmx .NET Help Files

http://digital.ni.com/public.nsf/allkb/0BE230A7DA6E655A8625707A0059E20B?OpenDocument