© National Instruments | 4-31M Series User ManualWhen the reference trigger occurs, the DAQ device continues to write samples to the buffer untilthe buffer contains the number of posttrigger samples desired. Figure 4-23 shows the finalbuffer.Figure 4-23. Reference Trigger Final BufferUsing a Digital SourceTo use AI Reference Trigger with a digital source, specify a source and an edge. The source canbe any of the following signals:• PFI <0..15>• RTSI <0..7>• PXI_STARThe source also can be one of several internal signals on your DAQ device. Refer to DeviceRouting in MAX in the NI-DAQmx Help or the LabVIEW Help for more information.You also can specify whether the measurement acquisition stops on the rising edge or fallingedge of AI Reference Trigger.Using an Analog SourceWhen you use an analog trigger source, the acquisition stops on the first rising edge of theAnalog Comparison Event signal.Routing AI Reference Trigger Signal to an Output TerminalYou can route AI Reference Trigger out to any PFI <0..15> or RTSI <0..7> terminal.All PFI terminals are configured as inputs by default.AI Pause Trigger SignalUse the AI Pause Trigger (ai/PauseTrigger) signal to pause and resume a measurementacquisition. The internal sample clock pauses while the external trigger signal is active andresumes when the signal is inactive. You can program the active level of the pause trigger to behigh or low.Reference TriggerPretrigger SamplesComplete BufferPosttrigger SamplesArtisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com
