Digital o/p from 6221

Question

I hv LV 8.0 acedamic kit along with PCI-6221 (68 pin).
using the Daqmx i generated a task that gives out a digital pulse o/p.
I hv attched my task. this will trigger myinstrument.
is thr any way i can avoid pull down the tsk menu in front panel and when ever i run the vi that particular task is taken.
is thr any way by which i can specify the no of pulses , high and low time , possibly time be feeded from front pannel rather than going to Edit NI-DAQmx task.
thanks and waiting for the help.
Attachments:
meter trigger.vi ‏11 KB

Answer 1

Hello,
I am having a bit of trouble understanding your description of your application.  Please correct me if I am wrong: you would like to generate a pulse train of a specific frequency with N pulses.  You then would like to wait a specific amount of time before regenerating this same pulse train.  This same pattern is repeated as many times as the user specifies.
If this is indeed your goal, I would recommend a different implementation than the one you have attached here.  This program uses software timing rather than hardware timing.  Although software timing should be fast enough for your application, it is not deterministic and thus is not guaranteed to be accurate.  If you do not need determinism in your application and prefer to use software timing, you will need to change this VI so that the time delay VI occurs at the correct sequence in your code.  This could be done, for example, with a sequence structure.  Since the time delay VI and your DAQ tasks are totally independent, right now there is no way to know whether the time delay will execute before or after the pulse output on any given loop iteration. 
I would strongly recommend that you set up a retriggerable pulse train generation rather than using software timing.  For an example of how to generate a retriggerable finite pulse train, see the LabVIEW example entitled Gen Dig Pulse Train-Finite-Retriggerable.vi found in the Example Finder under Hardware Input and Output >> DAQmx >> Generating Digital Pulses.  This example would have to be modified slightly for your application.  Rather than using a PFI line to retrigger the pulse train, you could use your multifunction DAQ device's analog sample clock for the trigger source.  If you aren't sure how to do this and would like a more detailed explanation then please let me know.
I know this is a lot of information so I hope I haven't confused you.  Let me know if you have any questions!
Message Edited by ElizabethL on 06-13-2007 11:00 AM