log input at specified time interval from the DAQ card and display it in the userinterface window. to set the specified time interval for data acquisition, what commands can i use and where i can find those commands? can u please help me in solving this?"I am not sure how fast you are wanting to sample data or if you are wanting to make multiple samples at these time intervals. (are we talking about seconds, mS, uS, etc...). Here are a couple different ways this can be done.
The first approach is the most straight forward. You could use one of the continuous examples on your hard drive C:\Program Files\National Instruments\CVI70\samples\easyio or one of the C examples at C:\Program Files\National Instruments\NI-DAQ\Examples\VisualC\Ai (requires support for Visual C to be installed) that make direct ni-daq driver calls. You would have to add a user interface and project to the later one.
Finally, if you want to perform a much slower acquisition, I would recommend using the asynchronous timer. There is
an example using it at C:\Program Files\National Instruments\CVI70\samples\toolbox called asyncdem.prj. This example does not have the DAQ stuff, but you could easily modify it to include a single sample acquisition in the timer callback. The concept of the asyncdem example is that it uses a software timer running in a separate thread to perform the operation. This allows you to perform other operations in the main thread.
I hope this will help.
Joshua
