Can somebody help me with this small project?

[jerryguo]

Dear Friends,

I have attached the .vi file so you can take a look at it. Basically I'm doing a simple control task that has the following steps:
Start---wait for time t1----send out a voltage via channel 1----wait for time t2----turn on 1394 camera----wait for time t3----starting saving an image sequence (fixed number of images)-----wait for time t4---send out another voltage via channel 2.

The .vi file you see here was modified using the example from the library (sequence.vi from Labview 8.2.1).  As you can see there are many "junk functions" I don't need but I still kept them in the program so I wouldn't screw up the camera function.
Basically I inserted a stacked sequence structure with proper timing delay inside the "Grab" case of the event structure (see the big block inside a while loop at the top of diagram) of original example code and built another event structure (see the big block at the bottom of diagram) for image sequence saving. The whole task is triggered by "Grab" button.

I was using a standard IEEE 1394 camera and USB 6009 DAQ card, I had no problem making these devices working independently. But when I tried to put everything together I encountered some issues. I couldn't get real time image display when I started the program. I think the issue was probably caused by the stacked sequence structure that I put inside the example event structure. Can anyone please give me any advice on how to modify the diagram so that I can get both real time image display and that sequence control task? And also how to make every step of my task independently controllable?  The camera function really makes the program complicated and I don't know where to start with. I'm just a beginner in Labview and have no idea on this kind of graphic programming....

Any help would be greatly greatly appreciated!!!

Thanks for looking

Jerry

[Vivek_N]

Hello Jerry,

I would try running your VI in 'highlight execution' mode. This can be done by clicking on the bulb in the top-left of the block diagram before running the VI. This will show you how the data is flowing in your VI. Most probably, you are not timing the sequences of events and the display of the image properly. Could you include all the events in one structure? This would depend on when you want to display the images with respect to the occurence of the events.

I hope this helps. Please post if you have any questions.

[jerryguo]

Thank yo Vivek, I know it's a long question and I really appreciate you reading through it:D
Yes I did that already and found some problem with my code, it has some thing to do with the handle of the event structure. I may ask you more if I can't solve the problem.

Best

Jerry