07-17-2002 06:55 PM
07-19-2002
09:24 AM
- last edited on
11-21-2025
10:12 PM
by
Content Cleaner
I'm not surprised at the behavior that you are seeing. When the acquisition is started the board is programmed with the acquisition size and when you change that it has to reprogram the board while it is acquiring, so either it will timeout or it just won't do it and you will only see the first size. I'm not sure why the diagnostics are failing but it sounds like you can reboot and that resolves the issue. I would recommend looking into a couple of alternatives. Variable Height Acquistion uses a hardware signal to indicate how many lines should be in an image. If you didn't have a signal you could generate one with a DAQ card or you could programmatically assert
and deassert one of the trigger lines on the 1424 but that would not be the most accurate depending on your line rate. The other alternative would be to set the image size to the largest size and then just crop the images.
Regards,
JR A.
Application Engineer
National Instruments
07-19-2002 12:06 PM