error 1074397150 in gated IMAQ acquisition

[jazeker]

Hi,

I have a SUI linescan camera which is read out with an NI 1427 framegrabber. I use an acquisition routine similar to LL ring acquisition. I want to gate the camera externally such that a fixed number of lines is acquired when the gate is high. So I put a TTL signal with duty cycle 50% on the gate of the camera. What should happen is that when I start grabbing the images from the camera, the buffer rate is half as high as without gating.

This is indeed the case SOMETIMES. In many cases labview doesn't start acquiring images and the acquisition 'while loop' is locked. The error is in IMAQ Extract Buffer->IMAQ Examine buffer->IMAQ img WaitForIMAQOccurence with error code 1074397150. Apparently the occurence is not made by the .dll imgSessionExamineBufferWithOccur This problem occurs even with a gating speed of >1 kHz, so it is no timeout issue I think. If I operate in a mode without gating, there is no problem and the acquisition rate is as expected.

Thanks in advance for the advise.

Sincerely,

Jeroen

[ninlmartijn]

Dear Jeroen,

Thank you for your post on our discussion forum. or some reason your video signal may be corrupt. If this is the case te following example may be suitable for you; http://sine.ni.com/devzone/cda/epd/p/id/3859 .

To test that your camera is returning valid images, try running some of the high level IMAQ examples that ship with LabVIEW by going to Help >> Find Examples.  In the middle folder list, browse to Hardware Input and Output, and select the IMAQ folder. Browse to the High Level folder, and try running some of the examples in this folder to verify that the camera is working properly with LabVIEW.

I hope this helps.

Best regards,

Martijn