Why are the triggering options in the DAQ Assistant grayed out?

[PartaCles]

Hello all,

I need to make a program that synchronously outputs and inputs signals. I've looked at many examples that use a programmatic approach and tried most of them, but to no avail (tons of errors and they never end up working, at all!). The DAQ assistant has been included in my last attempts (to simplify the overall program as well), but there is an issue; everytime I setup an analog input or output task I cannot choose my "Task Triggering" options in the DAQ assistant; all options under Start and Reference Trigger are grayed out except for "<None>". Is there something I am missing? I am using Labview 8.0 on Windows XP with a USB NI cDAQ-9172; my AI and AO devices are NI 9215 and 9263, respectively. Are these devices at all compatible with triggering in DAQ Assistant?

I'm guessing that there might be some greater error (maybe software?), any ideas?

Thanks

[Brian_R]

You must have a digital module in slots 5 or 6 of the cDAQ-9172 in order to perform digital triggering.  Then it will show up in MAX and the DAQ Express VI. 

Based on the description of what you are trying to accomplish ("synchronously outputs and inputs signals"), I believe there is a great example program that will work for you .  I have attached the code from our example finder.  It uses the AI start trigger to trigger the AO, resulting in synchronus I/O.  I hope this helps!

[PartaCles]

You were right, my modules were placed on the 1 and 2 slots, so I switched them to the 5 and 6, but it still didn't work. I tried to open the file you attached, but an error comes up saying that the file is of a newer LabView version (8.5, I've got 8.0). I looked on the example finder and found one that does simultaneous AI and AO (does it programmatically), but that one didn't work saying:

"Error -89136 occurred at DAQmx Write (Analog Wfm 1Chan NSamp).vi:1
Possible reason(s):

Specified route cannot be satisfied, because the hardware does not support it.

Property: SampClk.Src
Property: SampClk.ActiveEdge
Source Device: cDAQ1Mod6
Source Terminal: ai/SampleClock

Task Name: _unnamedTask<0>"

Now I am really confused! I thought this hardware DID support it... I tried rebooting, swapping 5 and 6, then rebooting again. I've tested each device and they seem to be doing AI and AO just fine, but without trigger. Also, after I switched them to 5 and 6, the trigger options were still grayed out.

[Brian_R]

To perform triggering, you will need your two AI and AO modules plus a DIO module (i.e NI-9401).  The 9401 would have to be in slots 5 or 6 because those are the only two slots that have access to the digital and counter lines.  However, you can trigger off of the PFI line in other slots.

If you just want to use synchronus I/O, you can have your AI and AO modules in slots one and two and it will work. 

The cDAQ-9172 User Manual contains more information regarding triggering and the slots you can use for specific functionality.

[PartaCles]

So, just to make sure I am understanding this; the DIO (NI 9401, for example) will set the triggering and timing for the AI and AO (NI 9215 and NI 9263). I am guessing that I will have to have the NI 9401 output a triggered signal for the AI and AO  to trigger from simultaneously? Meanwhile the NI cDAQ-9172 will have in slot 1 and 2 the 9215 and 9263 and in slot 5 or 6 (which support timing operations) the NI 9401?

[Brian_R]

That is correct.  In the example above, you see that the second task uses the sample clock of the first task to provide a start trigger.  To trigger the entire system from an external source, you would then provide a start trigger to the first task.  Include a start trigger that triggers of an edge of a DI line coming from a DIO module in slot 5 or 6.  This will cause the first task to wait for an external trigger while the second task is waiting for the first task to start.

I hope this helps!

[PartaCles]

The NI 9401 actually seems to suit my experiment just fine so my advisor has chosen to go ahead and order it, I will update you on how it works out. Thanks for your help!