Measurement Computing ADAC-LVi - Manual (Page 44)

Chapter 2 Utility Analog Input VIs
ADAC LabVIEW VI 38
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timeout limit in sec Time Limit in Seconds specifies the maximum length of time this
VI waits for a done buffer. You express time limit in seconds. If this VI does not receive
a completed buffer status prior to the timeout period, the VI returns an error.
error in (no error) Error in describes error conditions occurring before this VI executes.
This cluster defaults to no error.
Waveform Data Waveform Data is a two-dimensional array containing analog input
data in volts. The data appears in columns, where each column contains the data for a
single channel. The second (bottom) dimension selects the channel. The first (top)
dimension selects a single data point for that channel. This array is empty if convert to
volts is FALSE.
BUFFER STATUS ADAC-LVi buffers are not just arrays of data to a DAQ board's
subsystem data, but are structures that contains the buffer type, size, data array, current
sample count, hardware trigger points, completion flags, status flags, and error flags.
Some of these fields remain constant for the duration of the acquisition. Others contain
relevant information about the current condition of the buffer, and error conditions that
can occurred during the current acquisition.
The three structure variables that provide state/status/error information are the DoneFlag,
StatusFlag and ErrorFlags.
BufferType [U32] BufferType
Data Buffer type, DMA, Interrupt or Polling.
BufferSize [U32] BufferSize
Size of the buffer in bytes.
BufferWrite [U32] BufferWrite
Number of data samples in the buffer.
BufferRead [U32] BufferRead
Number of data samples obtained from a buffer.
TriggerPoint [U32] TriggerPoint
Buffer position number of the trigger point.
TiggerPointStart [U32] TriggerPointStart
Buffer position number of the pre-trigger data.