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

[Filipe A.]

Hello;

As your board only has two counters, you will be able to read only two sqaure waves at one time. You have two options at this point:
1) To acquire a PCI-6602 which has 8 counters
2) Do the measurement of the first two and then take the measurements of the last two square waves.
To do that, you can create a Labview sequence in which the first sequence does the first two square waves and the second sequence does the last two waves.
You can find a Labview example at Search Examples->I/O Interfaces->Data Acquisition->Counters->Pulse-Width Measurement->Measure Pulse (DAQ STC).vi, which does the width measurement. You can cheange that example to work with two pfi lines instead of only one, and create a sequence of events to do the same measurement on the last
two waves.
Hope this helps.
Filipe