Measure scan frequency using 2 e-series boards and an external clock.

I am setting up a data acquisition system in which the user has the ability to select between multiple sources for the scan frequency. The user can choose either hardware based and select the scan frequency or an external source, in this case, an encoder. When the user selects the external case, I would like to measure the scan frequency. I have a PXI chassis with 3 6071E DAQ boards. I have the encoder pulse train wired into the master board and would like to use one of the slave boards to count the pulses and measure the frequency. I based the code I developed on example code that shipped with LabView. However, when I drive the master board with a known frequency using its internal clock,
I measure 0 frequency on using the slave boards counter.
Attachments:
DAQ_3_Boards_-_State_Machine_-_Scaled_Array.llb ‏1525 KB

It sounds like you have your program setup to measure the frequency of the clock only when you are using an external source. The counter won't get an input if you are not using an external source, right? So, when you drive the master board with an internal clock, the counter will have nothing to count.

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Measure scan frequency using 2 e-series boards and an external clock.

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