Retriggerable Data Acquisition with NI DAQ Devices

Non X Series with no available counters: If you are not using an NI 63xx Multifunction I/O (X Series) DAQ board, analog input is not inherently retriggerable. However; you can retrigger a board by starting and stopping the DAQmx task each time a trigger is received. This will reconfigure the settings on the card and therefore re-arms the analog hardware trigger. This method, however, introduces significant hardware delays and hinders the ability to detect triggers that are close together. This may present issues where triggers are missed. One way to reduce the hardware delay is to explicitly set your task to be in the committed state before setting your task. Doing this eliminates the need to reconfigure the card with your analog input settings and can reduce some of the delay associated with this method, but there will still be an issue with delay involved in re-arming the trigger. See the NI-DAQmx help file linked for more information regarding the committed state. You can explicitly set your task to be committed by using the DAQmx Control Task VI under Functions Palette » Measurement I/O » NI-DAQmx » Task Config.