DAQmxReadCounterF64
- Updated2023-03-16
- 2 minute(s) read
int32 DAQmxReadCounterF64 (TaskHandle taskHandle, int32 numSampsPerChan, float64 timeout, float64 readArray[], uInt32 arraySizeInSamps, int32 *sampsPerChanRead, bool32 *reserved);
Purpose
Reads multiple floating-point samples from a counter task. Use this function when counter samples are interleaved, and are scaled to a floating-point value, such as for frequency and period measurements.
Parameters
| Input | ||
| Name | Type | Description |
|---|---|---|
| taskHandle | TaskHandle | The task to read samples from. |
| numSampsPerChan | int32 | The number of samples, per channel, to read. The default value of NI-DAQmx determines how many samples to read based on whether the task acquires samples continuously or acquires a finite number of samples. If the task acquires samples continuously and you set this parameter to If the task acquires a finite number of samples and you set this parameter to |
| timeout | float64 | The amount of time, in seconds, to wait for the function to read the sample(s). 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 read the requested samples. If all the requested samples are read, the function is successful. Otherwise, the function returns a timeout error and returns the samples that were actually read. |
| arraySizeInSamps | uInt32 | The size of the array, in samples, into which samples are read. |
| reserved | Reserved for future use. Pass NULL to this parameter. | |
| Output | ||
| Name | Type | Description |
| readArray | The array to read samples into. | |
| sampsPerChanRead | The actual number of samples read from each channel. |
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. |