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Problems with external counter direction

I have a DAQPad-6015 attached to a SC-2345, in slot 19 of the SC-2345 I have a SCC-CTR01.  Within MAX I have created a task to retrieve the counter information but because there is no option of a SCC-CTR01 I have configured it as a SCC-FT01.  Attached to the "SCR" input of the SCC-CTR01 I have a signal generator and on the test pannel I can see the counter count the edges as I wanted.  My next step is to externally control the direction with the "GATE" input on the SCC-CTR01 and have had no luck.  I am able to see the TTL signals from the SCC-CTR01 on the green connector stack, I can see the signal generator out on PFI 8 and I can see the "GATE" switch on PFI 9.  I am also able to switch the count direction by tieing P0.6 to 5 volts when in the mode of "Count Direction, Externally Controlled" is selected.  I am not able to connect PFI9 to P0.6 as there appears to be another output tied to P0.6.  Where do I go from here?
 
Ken
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Hello Ken,

For information about configuring the SCC-CTR01 module in Measurement and Automation Explorer(MAX), take a look at the following knowledgebase:

KB 3PRGG488: Configuring the SCC-CTR01 in MAX

For more information about how to configure the count direction with different DAQ cards, take a look at the following knowledgebase:

KB 3PJGJ2RM: Can I Use the SCC-CTR01 Module With Quadrature Encoders and Up/Down Event Counting?

Let us know if you have any further questions about implementing this functionality.

Regards,
Travis Gorkin
Applications Engineering
National Instruments
www.ni.com/support
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Travis Gorkin

I still don't see how to make the connections work?  I am trying to get this done with the DAC-assistant and no matter what I do I can't get the signals from the gate or scr input of the SCC-CTR01 to connect to the counter direction controls.  I looked at Document, ID: 3PJGJ2RM and I see some sort of code with nothing to do with the SCC-CTR01?  Can this not be done with the DC-assistant?  If there was a way do tristate the output attached to the counter direction line on the build-out connector in the SC-2345 so I could wire the output of the SCC-CTR01 across to the counter direction input bit P0.6.  Is there a way to do this?

Ken

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Hi Ken-

The code snippet in that KB shows how to use a DAQmx Property Node to override the default direction terminal in case you need an isolated input terminal for your count direction and are using an M Series device (which features configurable counter terminals)

I'm assuming you are using an E Series device judging by your P0.6 query.  To answer your question, Yes- you can use pin 16 on the built-in breakout area of the SC-2345 carrier to externally control the count direction of your counter.  There is no need to tristate the line as long as you specify "Externally Controlled" for count direction in your DAQ Assistant settings.  If you still require an isolated input terminal for the count direction you could use an SCC-DI01 module to interface directly with P0.6.  All of this information is available in the KB you mentioned.  Please let me know if you need additional clarification.

Thanks-

Tom W
National Instruments
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