AIChannelCollection.CreateFrequencyVoltageChannel Method (String, String, Double, Double, Double, Double, String)
- Updated2023-02-21
- 2 minute(s) read
Namespace: NationalInstruments.DAQmx
Assembly: NationalInstruments.DAQmx (in NationalInstruments.DAQmx.dll) Version: 20.7.40.49302
Syntax
public AIChannel CreateFrequencyVoltageChannel( string physicalChannelName, string nameToAssignChannel, double minimumValue, double maximumValue, double thresholdVoltage, double hysteresis, string customScaleName )
Public Function CreateFrequencyVoltageChannel ( physicalChannelName As String, nameToAssignChannel As String, minimumValue As Double, maximumValue As Double, thresholdVoltage As Double, hysteresis As Double, customScaleName As String ) As AIChannel
Parameters
- physicalChannelName
- Type: SystemString
The names of one or more physical channels to use to create one or more local virtual channels. - nameToAssignChannel
- Type: SystemString
One or more names to assign to the created local virtual channels. To use the physical channel name as the local virtual channel name, set this value to Empty. - minimumValue
- Type: SystemDouble
The minimum value expected from the measurement, in units. - maximumValue
- Type: SystemDouble
The maximum value expected from the measurement, in units. - thresholdVoltage
- Type: SystemDouble
The voltage 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
- Type: SystemDouble
A window, in volts, below thresholdVoltage. The input voltage must pass below thresholdVoltage minus hysteresis before NI-DAQmx recognizes a waveform repetition. Hysteresis can improve the measurement accuracy when the signal contains noise or jitter. - customScaleName
- Type: SystemString
The name of the custom scale to apply to the local virtual channel.
Return Value
Type: AIChannelThe newly created AIChannel.
Exceptions
| Exception | Condition |
|---|---|
| DaqException | The NI-DAQmx driver returned an error. |
Remarks
This method creates a local virtual channel for every physical channel name you specify. If you create multiple local virtual channels with one call to this method, you can specify a comma-delimited list of names for nameToAssignChannel. If you provide fewer local virtual channel names in nameToAssignChannel than you create, NI-DAQmx automatically assigns names to the local virtual channels.
If you do not provide a value for nameToAssignChannel, NI-DAQmx uses the physicalChannelName as the local virtual channel name. If you use nameToAssignChannel to create a name for the local virtual channel, you must use this name in other properties and methods.
The NI-DAQmx driver does not determine if the requested settings are possible until the task is verified. CreateFrequencyVoltageChannel(String, String, Double, Double, Double, Double, String) does not throw an exception for parameter values that are not compatible with your hardware or other settings in your task. To determine if all of the settings for a Task are valid, you must verify the task by starting the task, either with Start or by reading from or writing to the task, or by calling Control(TaskAction) with Verify.