two edge separation on 6110

[wdkeller]

Just trying to do a simple stimulus-response time mesurement on PCI-6110 board. Apparently it doesn't support the two-edge separation function. Measurement would be from ctr0 pulse out to one of the ai's. What would be the quickest, easiest way to do that?

[John_P1]

Could you please elaborate on this:

    Measurement would be from ctr0 pulse out to one of the ai's

What exactly are you trying to measure between?  It sounds like you're outputting a TTL pulse from a counter, then routing it through a circuit, and measuring the amount of time it takes to complete the propagation. 

If this is the case, I would use one AI channel hooked up directly to the CO, and another AI channel hooked up to the TTL signal at the end of your circuit.  Sampling at max rate (5 MHz) would give a 200 ns resolution.

Best Regards,

[wdkeller]

Right, it's just a simple response time measurement. We apply the TTL pulse output of the counter to the input of the circuit and measure the time it takes to respond at the output of the circuit. Readings should be in the neighborhood of 100-200 mS.

I tried to use "DAQmxCreateCITwoEdgeSepChan" to create the counter input channel, but apparently the PCI-6110 doesn't support that function. What function should I use?

[John_P1]

The way I would do this would be to acquire the analog data (with AI channels) and use software to determine how many samples have elapsed between pulses.  You can use the Threshold 1D Array function in LabVIEW to get the index of where your input signal exceeds a given threshhold.

You're correct that the 6110 does not support the Two Edge Separation method on its counters.

Best Regards,