How to use counters of PCI 6251 to count the number of pulses

Hello,
I have inputs from an optical encoder {pulse train} and i need to count the number of pulses for a short period of time to estimate the speed of the DC motor. Could you please tell me how to use the counters in PCI 6251 DAQ. I found something on DAQ STC, whichs says the input pulse should be connected to PF0 {ctr source}, but i have query where do i get the output {number of pulses counted in a particular period of time}.
Looking for your reply.
Thanks & Regards,
bsnr

Hi bsnr,
Thanks for the post!
In MAX (Measurement and Automation Explorer), if you find the device (DAQmx devices) and right-click, you can select pinouts - which should contain a table telling you which pins are what PFI lines.
Then, in labVIEW, you need to generate some code to use the choosen coutner in a task to count digital edges. If your not sure on this, go to Help>>Find Examples>>Hardware I/O>>DAQmx>>Counters.. and take a look at some of the code provide.
ps. It seems (maybe just your wording), but your expecting the counter output pin to provide the number of counted edges - this isn't the case.
Please let me know what you think?
Kind Regards,
Kind Regards
James Hillman
Applications Engineer 2008 to 2009 National Instruments UK & Ireland
Loughborough University UK - 2006 to 2011
Remember Kudos those who help!

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How to use counters of PCI 6251 to count the number of pulses

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