Trigger on PFI1 (or PFI0) does not work with NI PCI-6733 on NI-DAQmx 8.0.1 on openSuse 8.2

[MartijnSm]

Hello all,

I have an application in C that needs to play 3 wavefiles simultaneously on 3 NI PCI-6733 cards.

I am implementing this on:

OpenSUSE 8.2

NI-DAQmx 8.0.1

Following the samples from the SDK.

For various applications, I need to provide a choice to play:

- externally triggered via PFI1 on all 3 cards, or play immediately

- externally synchronized via PFI0 on all 3 cards, or play using internal clock

What I find out is that:

- internal clock with no triggering works

- external synchronization with no triggering works (a TTL clock signal on PFI0). The signal plays normally if I connect the external clock signal, and playback hangs if I do not connect it. This is expected.

- external triggering does not work (a TTL triggr signal on PFI1). The signal playback hangs, whatever signal I put to PFI1, even if I connect the clock signal to PFI1 instead of PFI0.

The code that I use:

        if (extTrig)
        {
             res = DAQmxCfgDigEdgeStartTrig(analogTasks[card],
                                           DAQ_EXTERNALSAMPLETRIGGER,
                                           extTrigRising ? DAQmx_Val_Rising : DAQmx_Val_Falling);
            Check("Set External Trigger Analog", res);

        }

where:

extTrig = TRUE

extTrigRising = FALSE

DAQ_EXTERNALSAMPLETRIGGER = "PFI1"

Check() is a function that prints an error message from DAQmxGetErrorString if res isn't zero

No error message was printed.

Any ideas?

[gaving]

---

@MartijnSm wrote:

- externally triggered via PFI1 on all 3 cards, or play immediately

What I find out is that:

...

- external triggering does not work (a TTL triggr signal on PFI1). The signal playback hangs, whatever signal I put to PFI1, even if I connect the clock signal to PFI1 instead of PFI0.

---

Does the playback start on all three and hang later?

You could try triggering just one card and exporting the start trigger (DAQmx_Val_StartTrigger) to PFI2 and have the other two cards trigger off of PFI2

http://zone.ni.com/reference/en-XX/help/370471W-01/daqmxcfunc/daqmxexportsignal/

-gavin