simultaneous analog in out from older labview version

[musclelab]

I wrote a bunch of programs for my research lab that used Labview 6.1 and NI-DAQ.

I upgraded to Labview 8.5 and NI-DAQmx, and wish to convert my programs.

I tried re-writing one, but for most of the VI's I used using NI-DAQ I can't seem to find similar replacements.

The task I want to do is produce an analog output from ao0 and ao1 while at the same time reading in data from ai0, ai1, and ai2.

How do I convert my programs?

[Brooks_C]

Hello Musclelab,

NI-DAQ and NI-DAQmx are completely different drivers so an automatic conversion is not possible.  As you said, you'll need to rebuild your VIs if you want to use NI-DAQmx.  The first step would be to confirm that your hardware is compatible with NI-DAQmx.  To do this please refer to the NI-DAQ Driver Support: Main Page and find your device.

The good news is that if your device is compatible with NI-DAQmx then there is likely a shipping example you can use to do the synchronized analog input and output you're looking for.  To access these examples open LabVIEW and go to Help>> Find Examples...  Then navigate to Hardware Input and Output>> DAQmx>> Synchronization>> Multi-Function.  The example called "Multi-Function-Synch AI-AO.vi" should be very similar to what you want.

If you find that one of these examples doesn't meet your needs here are a few good getting started references for DAQmx:

Getting Started with NI-DAQmx: Getting Started with NI-DAQmx Programming in LabVIEW

Learn 10 Functions in NI-DAQmx and Handle 80 Percent of Your Data Acquisition Applications

Getting Started with DAQmx

I hope this helps get you started, and if you have trouble determining if your card will work with NI-DAQmx then please reply with the specific model numbers of the card/s you're using.

Have a great day and stay strong!

[musclelab]

Under the Hardware Input and Output there is no DAQmx heading. I downloaded DAQmx for MacOS as the program I bought was for MAC, but only the windows DAQ was included. Most of my previous programs were indeed based on (heavily) modifying existing examples, but I can't find those examples. Is there an update that I am missing, or do I need to install my DAQmx differently?

Thanks for the help so far, it is indeed the examples that I'd like to see

Paul

[Brooks_C]

Hi Paul,

I didn't realize that you're using a Macintosh computer.  In that case you'll need to install NI-DAQmx Base.  Once you install this driver here is a KnowlegeBase article that has the file path to the example programs:  Where Can I Find NI-DAQmx Base Examples?

If you're still having trouble finding the examples it would be helpful to know the following:

1.  What version of OS X are you using?

2.  Are you on an Intel based Macintosh?

3.  Which version of NI-DAQmx Base do you have installed?

I hope this helps, and have a great day!

[musclelab]

The NI-DAQmx version I use was downloaded exactly 1 week ago, it said it was for Mac OSX. I can't find a version number.

I am running Mac OS X.5.2 on a dual 2.66 gig intel.

On my drive, under the path described, the example directory has files (4K each) have the extension .c and but these are no vi's. When I open these in labview, they pop up as text files. Does this somehow need to be mass-complied together with labview directories?

thanks for the help so far.

Paul

[Brooks_C]

Hello Paul,

Let’s see if you can see these examples in the example finder.  To do this open up LabVIEW and go to Help>> Find Examples...  Change the "Browse according to:" bullet to "Directory Structure."  You should see a daqmxbase folder here.  If these examples don't show up here or at /Applications/National Instruments/"LabVIEW version"/examples/daqmxbase then they likely haven't been installed, or they were installed before LabVIEW was.  If you installed DAQmx Base before LabVIEW then you should try reinstalling it so that the examples are put into the correct folder automatically.  Also you can check your installed software list to make sure that NI-DAQmx Base v. 3.1 is installed.  If you find that it’s not installed you can download and install NI-DAQmx Base 3.1 here.

Post back with what you find, and have a good night!

[musclelab]

Great, I'm almost there. Using the directory structure I can now see many DAQ examples. However the multi-Function one you suggested I start with in a previous reply does not show up. Many of the other ones will be useful though, but the synch AI-AO is the one I indeed really need. I do have DAQmx version 3.1 installed, and did so after installing Labview.

Paul

[Brooks_C]

Hello Paul,

The example I originally mentioned comes with NI-DAQmx, and not NI-DAQmx Base.  There are however a couple of different examples for NI-DAQmx Base on the developer zone:

1.  DAQmx Base Synchronized Finite Analog Input Analog Output 

2.  DAQmx Base Synchronized Finite Analog Input Continuous Analog Output 

I also opened the “Multi-Function-Synch AI-AO.vi” example from DAQmx and tried to convert it to DAQmx Base for you.  I replaced all the DAQmx VI’s with their DAQmx Base equivalent and removed the property nodes.  I think that I changed everything that isn’t supported in DAQmx Base, but I haven’t tested it on a computer that only has DAQmx Base.  If the example doesn’t open correctly for you, you may be able to fix it by replacing a missing VI with the correct DAQmx Base VI (i.e. replace DAQmx Create Channel VI with DAQmx Base Create Channel VI).

Cheers,