niHSDIO_ReadWaveformU8
Specific Function
C Function Prototype
ViStatus niHSDIO_ReadWaveformU8 (ViSession vi, ViInt32 samplesToRead, ViInt32 maxTimeMilliseconds, ViInt32* numberOfSamplesRead, ViUInt8[] data);
Purpose
Initiates a waveform acquisition on channels enabled for dynamic acquisition, waits until it acquires the number of samples in samplesToRead, and returns the acquired binary data.
Parameters
| Name | Type | Description |
|---|---|---|
| vi | ViSession | This handle identifies your instrument session. vi was obtained from niHSDIO_InitAcquisitionSession. |
| samplesToRead | ViInt32 | Specifies the number of samples to fetch. |
| maxTimeMilliseconds | ViInt32 | Specifies in milliseconds how long to allow the function to
complete before returning a timeout error.
A value of 0 causes the function to return immediately with up to the number of samples specified in samplesToRead. If you set maxTimeMilliseconds to a value other than 0, and a timeout occurs before all the samples are acquired, you receive a timeout error. If you specify a value for samplesToRead that is greater than the number of samples in the device memory, NI-HSDIO returns the available samples after maxTimeMilliseconds. A value of -1 causes the function to never time out. |
| numberOfSamplesRead | ViInt32 | Returns the number of samples that were successfully fetched and transferred into data[]. |
| data | ViUInt8[] | Returns the preallocated array where samples are written. |