Using the Trigger SMB Connector on cRIO 9012/9014 Controllers as Digital I/O Pin

Updated Apr 17, 2019

Reported In


  • cRIO-9012
  • cRIO-9014


  • LabVIEW

Operating System

  • VxWorks

Issue Details

I want to use the Trigger SMB pin on some 901x cRIOs that supposedly can be used as a DIO pin. I am unsure how to configure the SMB trigger connector as digital I/O.
The cRIO-9012 / 9014 operating instructions and specifications simply states "You can use the SMB connector of the cRIO-9012/9014 to connect digital devices to the controller. For example, if you connect the pulse-per-second output of a GPS device to the SMB connector of the cRIO-9012/9014, you can use the GPS device to correct for drift of the system clock."
How can I achieve this?


Preparatory steps


Step-by-Step solution

  1. Download and extract the 901x SMB Pin linked below that contains the example project.
  2. Open the example project file cRIO-901x SMB DIO.lvproj
  3. Right-click the cRIO Target and select Properties
  4. Make sure the chassis IP is entered correctly (brightly lit green dot on icon)
  5. In the Project Explorer, open the cRIO-901x Read SMB
  1. In the Block Diagram window, right-click the Call Library Function Node and select Configure...
  2. As Library Path, select the path to the vx_exec.out file downloaded before and click OK.
  3. Ignore the warning window about wrong DLL type.
  4. Save and close the VI.
  5. In the Project Explorer, right-click the Read and select Run.

Expected Result

The VI should execute without errors and the Data boolean indicator on the Front Panel should now display true (green). When pulling the pin to low, it should turn off (black).


Additional Information

 The procedure involves calling the following VX works functions on the realtime target:
  • dio5200ReadPin(1) to set as input
  • dio5200WritePin(1, true/false) to set as HIGH / LOW digital output
Please observe that the input/output characteristics for the SMB connector specified in the manual still apply.