Creates channel(s) that use a frequency-to-voltage converter to measure frequency.
task in specifies the task to which to add the virtual channels this node creates. If you do not specify a task, NI-DAQmx creates a task for you, and adds the virtual channels this node creates to that task.
error in describes error conditions that occur before this node runs. This input provides standard 'error in' functionality.
physical channels specifies the names of the physical channels to use to create virtual channels. The DAQmx physical channel constant lists all physical channels on devices and modules installed in the system.
You can also wire a string that contains a list, or range of physical channels, to this input. If you have an array of physical channels, use the DAQmx Flatten Channel String node to convert the array to a list.
name to assign specifies a name to assign to the virtual channel this node creates. If you do not wire a value to this input, NI-DAQmx uses the physical channel name as the virtual channel name.
If you use this input to provide your own names for the virtual channels, you must use the names when you refer to these channels in other NI-DAQmx nodes, such as the source input of the DAQmx Trigger node.
If you create multiple virtual channels with one DAQmx Create Virtual Channel node, you can specify a comma-separated list of names to assign to the virtual channels. If you provide fewer names than the number of virtual channels you create, NI-DAQmx automatically assigns names to the virtual channels.
units specifies the units to use to return frequency measurements.
|From Custom Scale||
Units a custom scale specifies. If you select this value, you must wire a custom scale name to the custom scale name input.
measurement range specifies the minimum and maximum values you expect to measure.
maximum value specifies in units the maximum value you expect to measure.
minimum value specifies in units the minimum value you expect to measure.
custom scale name specifies the name of a custom scale for the channel.
threshold level specifies in volts the level at which to recognize waveform repetitions. You should select a voltage level that occurs only once within the entire period of a waveform. You also can select a voltage that occurs only once while the voltage rises or falls.
hysteresis specifies in volts a window below level. The input voltage must pass below threshold level minus hysteresis before NI-DAQmx recognizes a waveform repetition. Hysteresis can improve measurement accuracy when the signal contains noise or jitter.
task out is a reference to the task after this node runs. The task contains any newly created virtual channels. If you did not wire a value to task in, NI-DAQmx automatically creates the task this output refers to.
error out contains error information. If error in indicates that an error occurred before this node ran, error out contains the same error information. Otherwise, error out describes the error status that this node produces.
Where This Node Can Run:
Desktop OS: Windows
FPGA: LabVIEW NXG does not support FPGA devices
Web Server: Not supported in VIs that run in a web application