How to measure two frequency simultaniously in a PCI 6014

[balajikasthuri]

Hi I am measuring RPM of two gear drives by measuring the pulse/second(Measure frequency.vi). I have interlinked the gate of counter1 to the output of counter2. Similarly I have connected the gate of counter2 to output of counter1. to measure frequency.
This way in a cycle one counter acts as gate counter while the other counter counts and later the counters changes their role.But my problem is that I have to measure the two counters frequencies simultaniously.

I cannot do period measurement becasue I have several irregular pulse widths generated in each cycle.

I am currrently experimenting with mesure period(DAQ-STC).vi. I have the following doubts in this VI.

1)Can I replaced source configuration fr
om internal timebase to external PFI source signal.

2)If I replace my source signal from internal timebase to the pulse generated from my gear drive then would at the end of 1 sec (when the counter is disarmed due to change of trigger signal state and hence end of while loop) will the count attribute contain the count of my ttl edges?

3) Would this be a accurate method for measuring frequency simultanuiously without using two counters?

Thanks.

[Bill B]

Hello,

Here is a link to example program which measures the frequencies of two signals simultaneously, by using Analog Output 1 as the gating signal.

http://venus.ni.com/stage/we/niepd_web_display.DISPLAY_EPD4?p_guid=B45EACE3E8E556A4E034080020E74861&p_node=DZ52329&p_submitted=N&p_rank=&p_answer=&p_source=Internal

Simply connect Analog Output 1 to the gate of both counters and then connect your signals to the sources of each counter. Make sure you specify counter 0 and counter 1 on the front panel before you run the VI, otherwise you will receive an error.

Regards,
Bill B
Applications Engineer
National Instruments

[balajikasthuri]

Thanks Bill.

I sopke to one of NI engineers after I posted my message and he suggested some thing similar. I was able to write a crude code of some thing similar. The code you directed me will further refine my current code.
Thanks,

Balaji

[balajikasthuri]

Hi Bill,

My computer recently failed and I am again in need of the example program you directed me in the below link
Can you kindly reprovide me this example. I am not able to currently accesses it in this link.kindly do the needful.
Thanks.

http://venus.ni.com/stage/we/ niepd_web_display. DISPLAY_EPD4?p_guid=B45EACE3E8E556A4E034 080020E74861&p_node=DZ52329& p_submitted=N&p_rank=&p_answer=& p_source=Internal