Measurement Computing ADAC-LVi - Manual (Page 35)

Chapter 2 Intermediate Analog Input VIs
ADAC LabVIEW VI 29
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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.
DoneFlag [U32] DoneFlag:
The Done Flag specifies the current state of a buffer. This flag can be set to any
of the three following conditions.
BUFFER_IDLE = 0 The buffer is available for use, but acquisition has not
started on this buffer.
BUFFER_DONE = 1 The buffer has been filled with samples and is available
for use in the user application.
BUFFER_INUSE = 2 The buffer is currently being filled with samples