Jim,
Thanks for contacting National Instruments.
While it is possible to configure the VISA Write to append a termination character, this is not the default behavior.
Here is a link to the document which describes how to do this:
Adding a Termination Character to VISA Serial WritesThe VISA Configure Serial Port also has inputs which address the termination character. However, the Enable Termination Char input enables the termination character for VISA
Reads only. This means that the VISA Read will stop reading after it receives the termination character. To make the VISA Writes automatically append a termination character, follow the procedure
linked above. Also, the Line Feed character is the default termination character, but that can be modified using the Termination Char input. The value for a Line Feed is 10, and the value for a Carraige Return is 13.
I hope this explains your question, if you need further clarification feel free to reply.
Sincerely,
Ross C
National Instruments
Applications Engineer