DAQmxCreateCIPulseWidthChan
int32 DAQmxCreateCIPulseWidthChan (TaskHandle taskHandle, const char counter[], const char nameToAssignToChannel[], float64 minVal, float64 maxVal, int32 units, int32 startingEdge, const char customScaleName[]);
Purpose
Creates a channel to measure the width of a digital pulse and adds the channel to the task you specify with taskHandle. startingEdge determines whether to measure a high pulse or a low pulse. You can create only one counter input channel at a time with this function because a task can include only one counter input channel. To read from multiple counters simultaneously, use a separate task for each counter. Connect the input signal to the default input terminal of the counter unless you select a different input terminal.
Parameters
|
Input
|
| Name |
Type |
Description |
|
taskHandle
|
TaskHandle |
The task to which to add the channels that this function creates. |
|
counter
|
const char []
|
The name of the counter to use to create virtual 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.
| Value |
|
Description |
|
DAQmx_Val_Seconds
|
|
seconds |
|
DAQmx_Val_Ticks
|
|
Timebase ticks |
|
DAQmx_Val_FromCustomScale
|
|
Units a custom scale specifies. Use customScaleName to specify a custom scale. |
|
|
startingEdge
|
int32 |
Specifies on which edge to begin measuring pulse width.
| Value |
|
Description |
|
DAQmx_Val_Rising
|
|
Rising edge(s). |
|
DAQmx_Val_Falling
|
|
Falling edge(s). |
|
|
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. |