syncronizing AI and AO - AI data is messed up

[Ed Bender]

I'm using AI and AO syncronously to do imaging.  No matter what I try, I always get black lines in my images.  I attached the VI but I can't attach an example image at the same time.  Basically the images have black lines and spots in a regular pattern, which depends on the sample rate.  Even when I go extremely slow, the lines appear.  Basically what's happening is I'm getting zeros mixed in with my AI data, presumably at constant time intervals.  Changing the buffer size has no effect.  Disconnecting my signals has no effect either (obviously my image goes away but I still get the lines) 

Any help would be greatly appreciated

-Ed Bender

University of Akron Physics Department

[Otis]

Hi Ed,

You're almost there!  The program that you attached looks pretty good except for one little, but important, detail.  There is a VI called Get Terminal Name with Device Prefix.vi that is used to make sure that the two tasks are synchronized correctly.  This VI will take a Task and a terminal and create a properly formatted device + terminal name to use as the source of the Trigger.

You can actually see what I'm talking about by opening LabVIEW and going to Help > Find Examples > Browse > Hardware Input and Output > DAQmx > Synchronization and opening the example Multi-Function-Synch AI-AO.vi.  This example shows you how to do almost exactly what it is that you are trying to do.

Regards,

Message Edited by Otis on 08-25-2005 02:55 PM