Synchronizing 3 cRIO-9045 with <1µs accuracy

[Deus_ex_Machina]

I need to ensure <1µs sync between my 3 cRIO chassis, and I want to go with IEEE 1588 with hardware support Technology.

I can not daisy chain multiple cRIOs, so I want to know if I can use Ring or Star Topology to make this work or use a different approach.

I need each cRIO to acquire data from 50 channels at a 10kHz sample rate and upload it to my database. I don't want to store all the data in a single controller and then upload to avoid bandwidth bottleneck, but I want each controller to upload independently.

[vacharya]

Hi Deus_ex_Machina,

You can not use the Ring topology for the same reason that you can not daisy chain multiple cRIOs. You can however use a star topology, if you introduced a PTP aware switch that supports transparent/boundary clock, you can achieve sub 1us synchronization with IEEE 1588 (PTP).

There are many switches available in the market, including the Cisco IE4000 switch recommended here.

A topology that comes to mind first is:

               database host

                     |

                     |

cRIO1 ---- switch ------ cRIO2

                     |

                     |

                  cRIO3