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Timestamped AInScan Measurements


domr001
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I'm using a USB-2637 to monitor multiple channels in the background while automatically activating a switch.

But I need to get the timing from switch activation until output signal.

Is it possible to get a timestamp with each measurement from AInScan?

Even a millisecond counter value - to get precise relative times of each measurement.

Thank you

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The USB-2637 does not generate time stamps.  With very few exceptions no MCC data acquisition device can generate time stamps.

However, when setup for hardware paced analog input scanning, the A/D is rigidly timed by the on board crystal oscillator and clocking circuitry.  For example, if the USB-2637 is set for a 1 KHz sample rate, you can be assured the A/D is sampling at 1 mS intervals or 1/SampleRate.

Knowing this, you can set your switch to be one of your analog inputs along with your other analog inputs. So that when the switch closure is detected (change in measured voltage from 0V to 5V or vice versa), you know that the next sample acquired in your list of channels will be 1/SamplingRate.  If you are looking for the difference in time from when the switch state changes and when something else is affected by it, all you need do is multiple the number of samples acquired between the 2 state changes by 1/SampleRate and you have your answer.

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