Error -50400 at DMA FIFO Read on LabVIEW Real-Time or Host Program

Updated Sep 17, 2018

Reported In


  • CompactRIO Controller
  • PXI FPGA Module for FlexRIO


  • LabVIEW
  • LabVIEW FPGA Module
  • LabVIEW Real-Time Module

Issue Details

I am trying to read a DMA FIFO on my host program but I receive Error -50400: Invoke Method:FIFO Read:

Why is this happening?


This error is a timeout and occurs due to one of the following:
  • The FIFO is not getting written to. This might happen because you aren't actually acquiring data, or updating data in your FPGA program. You can check if data is properly received by wiring indicators to the inputs of your FIFO Write in the FPGA program. 
  • The host program is timing out before the FPGA program has a chance to write to the FIFO. Increase the timeout of the FIFO Read method on your host program.


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