Two counter inputs and counter output NI 9401

I am trying to configure two counter inputs and one counter output on one NI 9401. I have looked and found how to configure digital lines in booth directions but it seems like I can only do two counters in all on one module. Can someone verify this for me or let me know how to get all three on to one module?
Thank you

Hi mschoenwald,
The counters are actually located on the backplane of whatever chassis you are using--I'll assume you are using cDAQ and not cRIO.
If you have the older <link no longer exists>, then there are only 2 counters available in general. You can access both from a single parallel (8 lines or less) digital module in slot 5 or 6 of the chassis.
The 2nd generation Compact DAQ chassis (including 9174, 9178, 9181, 9188, etc.) includes 4 counters. You may access them from any slot with a parallel module. There is no restriction preventing you from accessing all 4 simultaneously from a single module.
The 9401 is bi-directional and configurable by nibble (line0:3 may be configured one direction, and line4:7 another). However, it is quirky in that it requires the line direction to be configured before any of the tasks are started. This is because the data lines themselves are used to set the line direction behind the scenes. The best way to work around the behavior is to use DAQmx Control Task to explicitly reserve your tasks before any of them are started (see here). Keep in mind that the counter output should use the opposite nibble from the two counter input tasks.
Best Regards,
John Passiak

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Attachments:
DIO simultaneously error.vi ‏31 KB

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Looks the same to me
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Attachments:
Galvo_Monitor_3.vi ‏43 KB

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Two counter inputs and counter output NI 9401

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