Cannot Use Same Counter Physical Channel for Multiple NI-9474

Updated Sep 30, 2021

Issue Details

I have two NI-9474 which have 4 counter each, I need to use all 8 counters simultaneously. When creating a task in NI-MAX for both of the module, I am getting the error below :
 
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Solution

For majority of C-Series modules, the module do not contain their own counters. Instead, it will access the counters that are contained within the chassis. The modern cDAQ chassis have 4 counters within them, and this is what the DIO modules need to access.

When we try to access "ctr0" through any DIO module that supports this access, we are not accessing the module counter, we are accessing the chassis counter. We thus cannot have both modules using "ctr0" as this cannot be shared between the modules. Here are more information about cDAQ Module Support for Accessing On-board Counters.