How do I take longer samples and my control my tick count?

[relative0]

I have a few questions imbedded in my attachments, they go with graphs so that one can understand. How do I reset the time clock, I am trying to graph an indexed row of image pixels against the clock, it works but every time I run the VI, the clock jumps because it seems to have been counting even when I wasn't running the VI. I tried to create a subtraction function for this but all I get is an empty graph, the graph auto scales when the other graphs do but I don't see anything on it. How do I change this? How do I take longer samples (refer to graphs I sent), and also how do I make sure that my PCI-1424 IMAQ board is handshaking at the same rate as my KLI-2113 Kodak Imaging board?

Thanks much for A
NY help,

Brian

[BB_Phil]

Brian,

I have taken a look at your attachments, but I am still confused about the specifics of your application. It may help if you ask specific questions about "how something is done" instead of pointing to your program's results.

As for the PCI-1424 acquiring all of the images, you have to make sure that the grab function is looped fast enough to get all of the incoming frames from the camera. If you have a lot of code that must execute in the loop, you may miss frames (this can be seen if you add a large wait in the loop). One thing you can do is a ring acquisition because the IMAQ Extract.vi tells you how many buffers are acquired. This will tel you if you're missing images or not within a certain time. If you need total control of you timing, then
I suggest you use a trigger to trigger your camera at certain rates.

[relative0]

One of the questions I had about the graphs is how to get those super large time values out of there and just have normal time intervals like 100ms (0 to 100ms) not 100ms (9853800 to 9853900). How do I cut out all the extra time that has been added up since I started the VI the first time?


Brian

[BB_Phil]

It looks like you are using an XY graph. If that is the case, the extra time you want to get rid of is in your array. You need to cut that information out of your array so it doesn't show up on a graph. If you were using a chart, then you would you a property node to clear the old information out each time you run.

BB_Phil