Using NTP and IEEE 1588 Synchronization Simultaneously on a cRIO Network

Updated Dec 7, 2020

Reported In


  • NI-TimeSync

Issue Details

I have a network of cRIOs and need to synchronize them with independent DUTs. I would like to use NTP to synchronize my cRIO network to the independent DUTs with Simple Network Time Protocol (NTP), and use NI-TimeSync to synchronize my cRIO network together using software-supported IEEE-1588 synchronization. Is this possible?


This is possible, but there are a few limitations on your network you will need to take into account:
  • Only one of your cRIOs will be able to run NTP software, and that cRIO will need to always be the master device in your IEEE-1588 synchronization network. This cRIO will communicate and synchronize with your DUTs.
  • NTP will act as an accuracy bottleneck in this situation - the IEEE-1588 synchronization will only be distributing NTP time to the rest of your devices, and you will not be able to take advantage of the potentially tighter synchronization offered by IEEE-1588. If it's reasonable, synchronizing your entire network of DUTs and cRIOs to NTP would reduce the complexity of your application.
Additionally, installing NI-TimeSync to allow the IEEE-1588 synchronization will disable the NTP software installed on the device, so you will need to reinstall and reconfigure NTP software on your master cRIO using this guide.