Counter Output:General Properties:More:Auto Increment Count

When this value is greater than 0, NI-DAQmx generates progressively longer pulses until the count register rolls over. At that point, the generated pulses return to the original pulse width and grow progressively longer until the count register rolls over again.

Use this property to provide a clock to an analog input channel for equivalent time sampling (ETS). ETS is a data acquisition technique in which data on a periodic waveform with a frequency higher than the Nyquist frequency of the system is obtained by sampling the waveform at instants in time skewed in relation to the beginning of each period of the waveform.