Error -1073807339 VISA Timeout Error When Trying to Communicate to ADAM I/O Modules

Updated Apr 8, 2023

Reported In


  • LabVIEW



Issue Details

I am trying to communicate with ADAM modules in LabVIEW. I can connect to them in AdamApax .NET Utility software and when I use the terminal for command testing in that software - I get a response. When running the same thing in LabVIEW I get the following error:

Error -1073807339 occurred at VISA Read or VISA Write.

Possible reason(s):

VISA:  (Hex 0xBFFF0015) Timeout expired before operation completed.


The device is still waiting for the termination character of the message, and therefore not transferring any data back.
  • In your VIs and the VISA Test Panel you have to use a stop character. Often, strings transferred on a serial connection need to be terminated with an extra termination character, mostly \t or \n. This termination character can be needed additionally to the stop bit and VISA termination character defined with the VISA Configure Serial Port node. Check your device's datasheet and documentation for the correct termination characters.

For ADAM Modules an example of the termination character needed can be HEX code "0D".

Additional Information

  • Alternatively, you could use a serial port sniffer software such as Eltima Sodtware to look at the data the Adam Utility sends and learn how the transfers should look like.
  • Keep in mind that VISA Configure Serial Port uses \n by default, which could be breaking your communication as well.