Selecting Built In cRIO Serial COM Port Name In Real-Time VI

Updated Jan 19, 2023

Reported In


  • cRIO-9030
  • cRIO-9031
  • cRIO-9032
  • cRIO-9033
  • cRIO-9034
  • cRIO-9035
  • cRIO-9036
  • cRIO-9037
  • cRIO-9038
  • cRIO-9039
  • cRIO-9068
  • cRIO-9063
  • cRIO-9064
  • cRIO-9065
  • cRIO-9066
  • cRIO-9067



Issue Details

I am trying to do serial communication through VISA on my CompactRIO (cRIO) device that has a built-in serial port.  However, when I look in my VISA resources, I do not see the usual COM0, COM1, etc... that I am expecting.  The only options that I see are ASRL1:INSTRASRL2:INSTR, ... with the number of entries corresponding to the number of built in serial ports.


The built in serial ports on a CompactRIO (cRIO) will show up under VISA resources as ASRL1:INSTR, ASRL2:INSTR, ... by default.  This is the correct behavior, and if you select the corresponding port, it will use that port as the VISA resource.  You can see the serial port naming under Remote Systems >> Name-of-your-cRIO >> Devices and Interfaces and you can give a name to the serial port under Settings as shown in the image below.  This is where you can give the port a name of COM0 or COM1 if you would rather refer to your serial ports with those names.