pulse width measurement for continious trails of pulses of different width

[santosh1]

Dear all

           i am using labview 8.2 and cdaq analog and dio module.i am having one application that pendulum is moving to and fro motion in horizontaly.i would like to measure time taken by pendulum from one point to another point contioniously.i am using laser source and photo diode or laser sensor and generating train of pulses by elctronic circuit .i have attched photo of pulses and pendulum.can u recomend me which daq card is suitable for this and if any sample vi is there plz send to me as i am new for this.i want to acquire ,measure and data log for time period of pulse.i want to measure pulse duration of each oscilation and will avrage it

[Ray.R]

Santosh,

Please post all questions and discussions within this one thread.  You have started several other threads which are now pointing to this one.

Thanks,

R

[J_Thomas]

Hi santosh,

It sounds like what you what to do is a continuous buffered pulse width measurement.  I would begin by looking in the NI Example Finder. Open LabVIEW and then go to Help >> Find Examples.  Browse to Hardware Input and Output >> DAQmx >> Counter Measurements >> Period or Pulse Width.   Inside this folder you will find several pulse width examples like Meas Pulse Width-Buffered-Cont.vi.  This example uses a counter to perform a continuous pulse width measurement. This VI could be easily configured to work with an external pulse signal and your DIO cDAQ module by routing the external pulse signal through a PFI line to the counters located on the cDAQ chassis.  The DIO module needs to be in slot 5 or slot 6 in order to access the counters through a PFI line.

Hope this helps.

[santosh1]

Dear sir

             Thanks for ur suggestion.as per u told  i used continuous buffered pulse width measurement vi   from example and i used ni-9401 in slot no 5 then i conneced ttl output of function geneerator to  dio 0  and com of ni 9401.when i am running programme i got error attched here.plz help me.

with regards

santosh

[Ray.R]

Are you using an internal or external clock? You need a clock signal to acquire samples.

As mentionned near the bottom of the paragraph in the Possible Reason(s), you may have configured the task for external timing and no clock was supplied.  If that's the case, supply an external clock (or use the internal one).

R

Message Edited by JoeLabView on 07-28-2008 12:56 PM