a question about IMAQ PCI_1424

[astudent]

Thanks for your help.But it doesn't solve my problem.
I use IMAQ PCI_1424. There is a sample supplied by NI. The sample is in the directory "\NI-IMAQ\sample\msvc\ring\extractbuffer". I changed a little the sample. My programme gives
camera a pulse and the camera sends PCI_1424 50 frames in 2 seconds.
The question is that when I change the width of ROI(variable CanvasWidth) to more than 670,the PCI_1412 receive more or less frames other than 50 frames. Why?

My source code is in FIle Attachments.

[Kyle_V]

Astudent.

Which camera are you using? What is it's resolution?

If I understand you correctly, your frame rate fluctuates around 50 frames per second when you exceed an ROI of 670 horizontal pixels. Does the same thing happen in MAX when you adjust the acquisition window? What about with a simple grab program? If it works in MAX, then it's got to be a software issue, perhaps with the canvas itself.

Please give me some more details so I'll be better able to narrow down the culprit.

Kyle V
Applications Engineer
National Instruments
www.ni.com/ask

[astudent]

I posted my question a week ago.
The question was posted as following:
"I'm programming for IMAQ PCI-1424. Now I am confused for a problem:
IMAQ PCI-1424 created a pulse from extern_triger 1 to camera. When camera receives the pulse,it send IMAQ PCI-1424 50 frames image. But the frame number are not always 50. When the width of ROI is less than 670,IMAQ PCI-1424 can receive 50 frames. When the width of ROI is more than 670,IMAQ PCI-1424 can receive more or less frames."


I use a device to simulate Photobit MV13DSm camera.
Because PCI-1424 must send a pulse to camera before camera sends frame to PCI-1424, I can not use MAX to create a pulse to test camera.
Following your advice ,I use a grab programme to test my device. When I
set PCI-1424 width of ROI more than 680, the PCI-1424 will recieve more or less than 50 frames. It is very like the phenomenon when I use a ring mode programme.
I don't know why.
Can you help me ?

regards
astudent

[Kyle_V]

astudent. Could you please send me the camera file for the Photobit camera? I'd like to see how the 1424 is configured. From your first email, it sounds like the camera first receives a trigger and then outputs 25 frames/second for two seconds. Does it stop after that? Does the camera have a free run mode?
Last question, do you have any documenation on the camera that I could look through (website, manual, etc.)?

[astudent]

Yes,the camera first receives a trigger and then outputs 25 frames/second for two seconds. It stops after that. The camera runs this way.
I give you camera file for the Photobit camera and documents about the camera.