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To set the sample rate of a DAQmx Task, use the DAQmx timing VI and connect a Control to the "rate" input. If you want to be able to change the rate while the task is running (which on E Series & AO Devices cannot be done for analog input, only for analog output), you can use the DAQmx Timing Property Node and connect a control to the "Sample Clock:Rate" property.
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Michael P
National Instruments
