Trigger frequency

[anarkie]

Hello?

I have a question about triggering with specific frequency settings. I have PCI-6025E and AI was controlled by a pretrigger clock on PFI0 and trigger frequency is selective from 25Hz, 50Hz and 100Hz. Where can I find DAQmx functions dealing with trigger frequency?

Also, about shipped example "200307_trigger_example" doesn't work with PFI0 as a start trigger. It only works with /Dev1/20MHzTimeBase. In DAQ, my application works with PFI0 as a start trigger.

The original DAQ code is Select_Signal( 1, ND_IN_START_TRIGGER, ND_PFI_0, ND_LOW_TO_HIGH ); 

Thanks,

Message Edited by anarkie on 06-30-2009 02:36 PM

[anarkie]

The trigger on PFI0 doesn't work. I tested DAQ code on my device; it works fine but DAQmx code with DAQmxCfgDigEdgeStartTrig() doesn't work

This is a main function.

This is a callback function.

And the bool32 done is coming from...

[ManLongAtNI]

DAQmx function properties dealing with trigger frequency can be found in the NI DAQmx C Reference Help, included when you install support along with the driver. Does your task start, or do you receive an error? Also what is being wired into the PFI line that is suppose to be causing the trigger?

Regards,

Glenn

Applications Engineer

National Instruments

[anarkie]

Thanks for reply. The device is working fine with DAQ code. It produces +5 V DC. And about DAQmx function, what is the exact function dealing with trigger frequency? There are trigger functions but their parameters are taskhandler and trigger type. I need a digital pre-trigger as a start trigger on PFI0 pin.

The device, the radar,  is working fine with the start trigger on PFI0. When I use function like above, the acquisition is holding for and infinite time and never returns anything. Besides the trigger frequency problem, why DAQmx can't handle start trigger on PFI0?

Is there any function ordering problem in my code?

Thanks,

Message Edited by anarkie on 07-02-2009 08:52 AM

[ManLongAtNI]

Can you clarify what you mean by the 'trigger frequency'? There isn't a specific property attributed to this since the frequency would be based on the rising edge of the pulse train of source. Are you receiving an error when you set the start trigger on PFI0? The start trigger "Configures the task to start acquiring or generating samples on a rising or falling edge of a digital signal" so as long as such a signal exists and is wired to the PFI0, it should work accordingly. 

Regards,

Glenn

[anarkie]

Thanks for comment. It is all about this function. Actually, the frequency was not the real matter.

I have wrote this problem today afternoon in new thread below.

http://forums.ni.com/ni/board/message?board.id=250&message.id=49957#M49957