IMAQ Error -1074397151 When Changing an Analog Attribute During a Grab Primary Software: Driver Software>>NI-IMAQPrimary Software Version: 3.5.1 Primary Software Fixed Version: N/A Secondary Software: LabVIEW Development Systems Hardware: Image Acquisition (IMAQ)>>Analog Image Devices
Problem: I have an analog NI-IMAQ frame grabber that I am acquiring images from in LabVIEW, and I would like to change an Analog Attribute while grabbing my images. For example I would like to be able to change my White Reference Voltage while acquiring my images so that I can adjust the reference voltage before I start my main acquisition. I am getting the error -1074397151, which says “can’t perform request – acquisition in progress.” Can I change an analog attribute while acquiring images? Solution: Unfortunately, you can not change the analog attributes while the Grab is in the middle of acquiring images. You will have to stop the acquisition, change the attribute, and then start the acquisition up again. You can refer to the HL Analog Attributes.VI example program that ships with the NI-IMAQ driver to see how to change analog attributes. For example, you can use this example inside of a loop until you choose the White Reference Level that works for you. Then you can keep the IMAQ Session open, and then set up a normal Grab in the next part of your program, in order to acquire at faster rates. When you change the Voltage Level in the Measurement and Automation Explorer, what really happens in the background is that the Grab actually stops the acquisition and then starts up again when the attribute has changed. Related Links: Vision Home Machine Vision Hardware: Analog Attachments:
Report Date: 03/16/2007 Last Updated: 03/22/2007 Document ID: 47FFPKHB |
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