measuring duty cyclse of the signals at PFI through counter

[saqib]

I have NI PCI-6052E-DAQ card. I have four square waves at PFI lines. I want to calculate the high time of each signal picking the signals one by one from PFI lines using triggering concept for counter to start with rising edge and stop with falling edge and then . This concept is already used in measring-9-frequencies.vi
Please Email me with plain explaination for your answer.
My Email: s_saqib_2000@yahoo.com

[Joe acquisition]

From bsukpraphrute@yahoo.com

PCI-6052E-DAQ card is a very nice piece you have.
LabVIEW got the time function. It is very easy to find. But you are about to measure the mSec(1/1000 of sec), Or even uSec (1/1000000 of sec).
First case IF you want to measure in mSec. You can use a tick count function. When you detect the rising edge, then you call this function as a starting time and put it to a variable. And in the same maner, when you detech the falling edge you call the same function and put it to a stopping time variable. Then you can calculate the triggering time and put it to the triggering time variable. However you only write to this variable when the previous value is smaller than the current value. If you wonder how to create variable. you migh
t concider to create a indicator in labview. Indicator can be use as a variable and it is good for debug too. And you can go from there.

Second case what if I want to measure in uSec. I would consider to use the Osiloscope to do the job. You might have to invest in GPIB card and find a Osiloscope that have GPIB outlet. That what I would prefer to do so. But you can get away with the Serial Osiloscope. The DLL option to calculate the time in uSec. I would not recommend you to do so. It is not very precise.

Good Luck 🙂
If you want more help, Please e-mail me at bsukpraphrute@yahoo.com