How accurate is the timing across multiple 6556 cards?

[joer1]

I need to have 42 high speed digital pins  to test a MRAM.  I have 2 PXIe 6556 cards but don't know how tight/accurate the syncronization of the two boards is. 

I didn't see any specs that talk about using multiple cards.  Anyone know what I can expect to achieve?

Thanks,

Joer1

[sunaenae]

Hi Joe,

It looks like William may have answered your question in your service request. However, I will reiterate the information again here:

When synchronizing two cards in one PXIe chassis, the most effective method is to use TClk. This will have both devices PLL to the 10 MHz reference clock, and share their start trigger. This would let you synchronize the devices to within 500 ps, which should work for your 35 ns read access time. Here is a resource on what NI-TClk is and how to use it: https://www.ni.com/en/shop/pxi/national-instruments-ni-tclk-technology-for-timing-and-synchroni.html

There is also a shipping example, Multi-Device Dynamic Generation (TCLK), under Hardware Input and Output>Modular Instruments>NI-HDSIO>Synchronization that might help get you started.

Hope that helps! 🙂

[joer1]

Yes,  William did a great job tracking it down for me.

Thanks All!

Joe Riordan