2 Square signal to frequency with DAQCard ?

[Yvan]

Hello,

My configuration : PC portable P4 / 1.8GHz, Win 2000, Labview 7.0, DAQCard AI-16E-4, BNC 2110 and two magnetic speed sensors (6000rpm, 120 top/rotary)

1) I would like to recorde the two frequencies with the two counters of the DAQCard. Can I do it with my configuration (2 counters are enough ?) ?

2) Can I synchronize these two inputs with analog inputs ? If not, which configuration I need for ?

Thanks a lot,

Yvan

[Mathieu_R.]

You can make a frequency measure with only one counter. This method use the internal timebase as source and your input signal as gate: the process take the number of clock period in a period of your input to compute it's frequency.

Accuracy of this method is quite good if the input frequency is small compare to the internal timebase. So with the sensor you described:
    6000rpm => 100 rotary per second
    with 120 top per rotary => 12000 top per second
The AI-16E-4 use a 20MH internal timebase, so I think there is no problem

More information about frequency measurement...

For the synchornisation, I'm not sure to clearly understand what you need, but take a look to the DAQmx timming and DAQmx start trigger VIs.