NI PCI 6534 Digital I/O using SCB-68: PFI low resistance can't trigger

[mpeters]

Hi,

I am trying to trigger my NI PCI 6534 Digital I/O card (https://www.ni.com/pdf/manuals/371464d.pdf) and have used the SCB-68 breakout board (https://www.ni.com/pdf/manuals/371745c.pdf) for routing my wires.

I have set up this and my other NI cards such that when I send a digital high signal to their PFI ports, it triggers them to move to the next programmed value.

This approach works for the NI 6733, NI 6738, and NI 6602 cards I have. However, for the 6534, the PFI port 2 resistance is only 50 ohms, and my device that triggers the via the PFI ports is unable to drive enough current to trigger it. The PFI port 2 and 6 are the only ports that can be used for triggering. 

Does anyone have a suggestion for why this could be and how to fix it? Is it more likely to be a problem with the SCB-68 breakout board or the PCI card itself?

Thank you for your time

[santo_13]

Have you configured SCB-68 in direct feedthrough mode?

Refer compatibility of accessories in this article - https://www.ni.com/en-us/support/documentation/supplemental/17/digital-instrument-cable-and-accessor...

[mpeters]

Thanks for the response! I just checked and confirmed that the switches are in the correct positions.