Pulse Measurement Channel Properties (CI)

Configure counter input (CI) channel properties to measure pulse specifications.

A pulse specification is a pairing of high time and low time values.
Note In addition to X Series DAQ devices, PXIe-6612 and PXIe-6614 devices also can perform a pulse measurement in VeriStand.
VeriStand returns measurements for pulse specifications as pairs of frequency and duty cycle values. You can access these values for each counter input channel that performs pulse measurements through two additional channels, Frequency and Duty Cycle, that appear under the counter channels in System Explorer.
Note If you assign this measurement type to one or more counter input channels, you cannot assign a different measurement type to other counter input channels on the same device.
Property/Section Description
Minimum Value The minimum value you expect to measure before VeriStand performs any scaling or calibration.
Maximum Value The maximum value you expect to measure before VeriStand performs any scaling or calibration.
Sample Clock Source Specifies the name of the source terminal of the sample clock. You can use an internal counter timebase when performing counter measurements or an external timebase. For more information, refer to Terminal Names in the NI-DAQmx Manual.
Sample Clock Rate Specifies in hertz the sampling rate in samples per channel per second. If you use an external source for the sample clock, set this input to the maximum expected rate of that clock.
Active Edge Specifies whether a timebase cycle is from rising edge to rising edge or from falling edge to falling edge:
  • Falling—Falling edge(s).
  • Rising—Rising edge(s).
Timeout Value

Specifies an amount of time to wait for the channel to return valid data. VeriStand considers invalid data to be repeated values, which might occur if the system attempts to read data faster than the Sample Clock Rate property.

When VeriStand reads invalid data, it continues to read from the channel while it counts until the Timeout Value. VeriStand will return values of NaN until the channel returns valid data again.
Note For device specific information about the default terminals used for counter measurements and generations, refer to Connecting Counter Signals.