DAQmxCreateAIFreqVoltageChan

int32 DAQmxCreateAIFreqVoltageChan (TaskHandle taskHandle, const char physicalChannel[], const char nameToAssignToChannel[], float64 minVal, float64 maxVal, int32 units, float64 thresholdLevel, float64 hysteresis, const char customScaleName[]);

Purpose

Creates channel(s) that use a frequency-to-voltage converter to measure frequency and adds the channel(s) to the task you specify with taskHandle.

Parameters

Input
Name	Type	Description
taskHandle	TaskHandle	The task to which to add the channels that this function creates.
physicalChannel	const char []	The names of the physical channels to use to create virtual channels. You can specify a list or range of physical channels.
nameToAssignToChannel	const char []	The name(s) to assign to the created virtual channel(s). If you do not specify a name, NI-DAQmx uses the physical channel name as the virtual channel name. If you specify your own names for nameToAssignToChannel, you must use the names when you refer to these channels in other NI-DAQmx functions. If you create multiple virtual channels with one call to this function, you can specify a list of names separated by commas. If you provide fewer names than the number of virtual channels you create, NI-DAQmx automatically assigns names to the virtual channels.
minVal	float64	The minimum value, in units, that you expect to measure.
maxVal	float64	The maximum value, in units, that you expect to measure.
units	int32	The units to use to return the measurement. Name Description DAQmx_Val_Hz hertz DAQmx_Val_FromCustomScale Units specified by a custom scale. Use customScaleName to specify a custom scale.
thresholdLevel	float64	The voltage level at which to recognize waveform repetitions.
hysteresis	float64	Specifies in volts a window below thresholdLevel. The input voltage must pass below thresholdLevel minus hysteresis before NI-DAQmx recognizes a waveform repetition. Hysteresis can improve measurement accuracy when the signal contains noise or jitter.
customScaleName	const char []	The name of a custom scale to apply to the channel. To use this parameter, you must set units to DAQmx_Val_FromCustomScale. If you do not set units to DAQmx_Val_FromCustomScale, you must set customScaleName to NULL.

Return Value

Name	Type	Description
status	int32	The error code returned by the function in the event of an error or warning. A value of 0 indicates success. A positive value indicates a warning. A negative value indicates an error.