Select_Signal is to DAQmxExportSignal or DAQmxCfgDigEdgeStartTrig?

[anarkie]

Hello?

My DAQ code is Select_Signal( 1, ND_IN_START_TRIGGER, ND_PFI_0, ND_LOW_TO_HIGH ). Is this code converted to DAQmxExportSignal or DAQmxCfgDigEdgeStartTrig?

We are using an external pre-trigger source on PFI0 pin. I searched this forum and the manual but their example is reversed to my case. The example is:

Select_Signal

In manual:

"To send the analog input start trigger on to RTSI line 3, use the following call:"

Select_Signal(deviceNum, ND_RTSI_3, ND_IN_START_TRIGGER, ND_LOW_TO_HIGH);

I tested DAQmxErrChk (DAQmxCfgDigEdgeStartTrig(taskHandle, "/Dev1/PFI0", DAQmx_Val_RisingSlope)); but it doesn't work with DAQmx. The device is working fine with old DAQ code. 

[anarkie]

In this example, it uses APFI0 pin; but my case is about digital trigger, not analog trigger. 

http://zone.ni.com/devzone/cda/tut/p/id/5958

When I set PFI0 as a trigger source in MAX as the example, it causes an error. I couldn't not select any analog trigger, for PCI-6025E doesn't support it.

[jschwartz]

Hi anarkie,

When you say that your device doesn't work, what do you mean?  Are you getting any errors?  What are you doing with your program? What did your old DAQ code do?

[anarkie]

The device well accepts AI with old DAQ code but hangs with DAQmx code. It just hangs and keeps waiting for AI if I enable external digital trigger on PFI0. I have +5 V producing TTL connected to pin PFI0.

[jschwartz]

Hi anarkie,

I think that this might be something with your syntax.  Your code is:

DAQmxErrChk (DAQmxCfgDigEdgeStartTrig(taskHandle, "/Dev1/PFI0", DAQmx_Val_RisingSlope));

From the help, the value for trigger edge should be DAQmx_Val_Rising not  DAQmx_Val_RisingSlope.