DAQ_Dynamic Digital Pattern Measurement Library

DAQ_Dynamic Digital Pattern Measurement Library VIs enable dynamic digital measurements on one or more digital channel lines or on an entire port in a digital module. This library is applicable for TestScale digital input modules or channels that support hardware-timed digital waveform characteristics.

Note This library supports both Port and Digital lines from a single module to measure dynamic digital patterns. Multi-module support is not applicable for this library and will produce errors.
  1. Use the DAQ_Dyn Dig Meas Initialize VI to initialize hardware and create a DAQmx Task for dynamic digital pattern measurement.
  2. Pass the dynamic digital pattern measurement DAQmx Task to the DAQ_Dyn Dig Meas Configure and Measure VI.
  3. Configure the DAQ_Dyn Dig Meas Configure and Measure VI.
    • Configuration Settings—Configure the timing related parameters for dynamic digital pattern measurement. The Timing setting configures sample clock source input, sampling rate, number of samples, and the sample timing engine used for the DAQmx Task.
      • Acquisition Time = Number of Samples/Sample Rate
      • Specify Auto to automatically select the timing engine.
      Note For NI 63xx (X Series) and other DAQ devices, use Auto mode only. The sample timing engine is only used for cDAQ and TestScale platforms, which support multiple timing engines.
      Note Refer to the relevant specifications document to identify the maximum sampling rate for your device. Values that exceed the maximum sampling rate generate errors.

      Configure triggers to start the source or measurement based on various trigger events. Trigger options include no trigger or digital start triggers.

    • Output Data—The VI outputs the following data.
    • Measured Digital Pattern—Displays the captured digital voltage waveforms.
    • Port Digital Data—Provides the derived post-analyzed port digital data in U32 format from the captured digital patterns.
  4. Wire the updated dynamic digital pattern measurement task from DAQmx Task Out.
  5. Close the dynamic digital pattern measurement task using DAQ_Dyn Dig Meas Close VI.

Best Practices

  • For faster measurements, set the maximum sampling rate possible for the given Sample Clock Source input and assign a smaller Number of Samples to capture.
  • For better resolution, increase the number of samples (for example, 1000 samples).
Figure 30. Connection Block Diagram