DAQmxWriteCtrFreqScalar
int32 DAQmxWriteCtrFreqScalar (TaskHandle taskHandle, bool32 autoStart, float64 timeout, float64 frequency, float64 dutyCycle, bool32 *reserved);
Purpose
Writes a new pulse frequency and duty cycle to a continuous counter output task that contains a single channel.
Parameters
| Input | ||
| Name | Type | Description |
|---|---|---|
| taskHandle | TaskHandle | The task to write the sample to. |
| autoStart | bool32 | Specifies whether or not this function automatically starts the task if you do not start it. |
| timeout | float64 | The amount of time, in seconds, to wait for this function to write all the samples. The default value is 10.0 seconds. To specify an infinite wait, pass -1 (DAQmx_Val_WaitInfinitely). This function returns an error if the timeout elapses. A value of 0 indicates to try once to write the submitted samples. If this function successfully writes all submitted samples, it does not return an error. Otherwise, the function returns a timeout error and returns the number of samples actually written. |
| frequency | float64 | Specifies at what frequency to generate pulses. |
| dutyCycle | float64 | The width of the pulse divided by the pulse period. NI-DAQmx uses this ratio, combined with frequency, to determine both pulse width and pulse delay. |
| reserved |
|
Reserved for future use. Pass NULL to this parameter. |
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. |