How to monitor an analog input channel while outputing waveform on the same card

[BrianFarrell]

I am using the easy I/O library in labwindows to output a single-shot waveform. The problem is that I need to monitor an analog input channel on the same card (6071-E) while the waveform is being sent out. It seems as though the program is not reading the input channel until the waveform is done being sent out.

[Brent_R]

Some of the Easy I/O functions do not return until all of the data has beed acquired (AI) or sent out (AO). This is described in the NI-DAQ help, which you can find at Programs >> National Instruments >> NI-DAQ >> NI-DAQ Help.

Take a look at the example below for information on performing simultaneous analog input and output. In this example the two operations are synchronized to a common clock, however this is not required.

Simultaneous Input and Output Example

Regards,

Brent R.
Applications Engineer
National Instruments

[Filipe A.]

Hello;

The easy I/O functions are not the ones you need to use for this sort of applications.

You need to set up a DAQ task in which the Analog Output update clock signal will be used as the AI ScanStart as well. So, every point you send out to the Analog Out channel, will correspond to an Analog Input channel data point to be read.

I'm attaching a CVI code example that shows how to so do that.

Hope this helps.
Filipe A.
Applications Engineer
National Instruments