Maximum Array Size That Can Be Written from LabVIEW to a Digital I/O Module

Updated May 15, 2023

Reported In


  • PXI Digital I/O Module


  • LabVIEW


  • NI-DAQmx

Issue Details

I'm trying to determine the maximum array size that I can write from LabVIEW to my Digital I/O Module. The specifications for my device list an onboard memory size but it appears I can write an array larger than that memory from LabVIEW to the device. Why is this and how can I determine the maximum array size that can be written to the device?


Using the DAQmx Write VI in LabVIEW to write an array to a Digital I/O module will automatically buffer any results that cannot be immediately stored on the module into the PC's memory. The device driver will then transfer the data from the PC's memory buffer to the onboard memory of the module as the module's onboard memory space becomes available. Therefore, the only limiting factor for the maximum size of an array will be LabVIEW's memory limitations on the PC.