IviCounterBase Capability Group
To measure frequency, the counter counts the number of crossings of the measured signal through a given level at a given slope. Built-in hysteresis rejects signal noise. Some counters provide autotrigger, which enables them to measure frequency without specifying the level and direction of the crossing.
The counter takes the measurement for a specific amount of time, called the gating time.
The most general triggering scheme for frequency or period measurement is shown in the following figure.
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Typical Counter Timer Diagram
IviCounterBase VIs
IviCounter Configure Channel Filter Enabled
IviCounter Configure Channel Level
IviCounter Configure Channel Slope
IviCounter Configure Continuous Totalize
IviCounter Configure Duty Cycle
IviCounter Configure Edge Time
IviCounter Configure Edge Time Reference Levels
IviCounter Configure External Start Arm
IviCounter Configure External Stop Arm
IviCounter Configure Frequency
IviCounter Configure Frequency Manual
IviCounter Configure Frequency Ratio
IviCounter Configure Frequency With Aperture Time
IviCounter Configure Gated Totalize
IviCounter Configure Period With Aperture Time
IviCounter Configure Pulse Width
IviCounter Configure Start Arm
IviCounter Configure Timed Totalize
IviCounter Configure Time Interval
IviCounter Fetch Continuous Totalize Count
IviCounter Start Continuous Totalize
IviCounter Stop Continuous Totalize
IviCounter Is Measurement Complete
IviCounterBase Properties
IviCounter Measurement Function
IviCounter Channel Attenuation
IviCounter Channel Filter Enabled
IviCounter Frequency Resolution
IviCounter Frequency Aperture Time
IviCounter Frequency Estimate Auto
IviCounter Frequency Resolution Auto
IviCounter Period Aperture Time
IviCounter Pulse Width Channel
IviCounter Pulse Width Estimate
IviCounter Pulse Width Resolution
IviCounter Duty Cycle Frequency Estimate
IviCounter Duty Cycle Resolution
IviCounter Edge Time Reference Type
IviCounter Edge Time Resolution
IviCounter Edge Time High Reference
IviCounter Edge Time Low Reference
IviCounter Frequency Ratio Numerator Channel
IviCounter Frequency Ratio Denominator Channel
IviCounter Frequency Ratio Numerator Frequency Estimate
IviCounter Frequency Ratio Estimate
IviCounter Frequency Ratio Resolution
IviCounter Time Interval Start Channel
IviCounter Time Interval Stop Channel
IviCounter Time Interval Estimate
IviCounter Time Interval Resolution
IviCounter Phase Input Channel
IviCounter Phase Reference Channel
IviCounter Phase Frequency Estimate
IviCounter Continuous Totalize Channel
IviCounter Gated Totalize Channel
IviCounter Gated Totalize Gate Source
IviCounter Gated Totalize Gate Slope
IviCounter Timed Totalize Channel
IviCounter Timed Totalize Gate Time
IviCounter External Start Arm Source
IviCounter External Start Arm Level
IviCounter External Start Arm Slope
IviCounter External Start Arm Delay
IviCounter External Stop Arm Source
IviCounter External Stop Arm Level
IviCounter External Stop Arm Slope
IviCounter External Stop Arm Delay