RelativeTo

Data Type:	int32
Description:	Specifies the point in the buffer at which to begin a read operation. If you also specify an offset with Offset, the read operation begins at that offset relative to the point you select with this property. The default value is DAQmx_Val_CurrReadPos unless you configure a Reference Trigger for the task. If you configure a Reference Trigger, the default value is DAQmx_Val_FirstPretrigSamp.

Valid values

DAQmx_Val_FirstSample	10424	Start reading samples relative to the first sample acquired.
DAQmx_Val_CurrReadPos	10425	Start reading samples relative to the last sample returned by the previous read. For the first read operation, this position is the first sample acquired or the first pretrigger sample if you configured a reference trigger for the task.
DAQmx_Val_RefTrig	10426	Start reading samples relative to the first sample after the reference trigger occurred.
DAQmx_Val_FirstPretrigSamp	10427	Start reading samples relative to the first pretrigger sample. You specify the number of pretrigger samples to acquire when you configure a reference trigger.
DAQmx_Val_MostRecentSamp	10428	Start reading samples relative to the next sample acquired. For example, use this value and set Offset to -1 to read the last sample acquired.