How to Write Conditional Formula for Data Logging Control in NI VeriStand Workspace

Updated Dec 23, 2019

Reported In


  • VeriStand

Issue Details

I wanted to use the Data Logging controls on NI VeriStand workspace, however, I am unaware about the process to do so. What is the proper syntax that will be accepted by the Conditional Formula field in Data Logging control?

VeriStand is not able to parse the syntax written and marks it as invalid.


Follow the steps mentioned below to create a formula with an accepted syntax:

1) Type out a variable name of your choice along with the operators and limits in the Conditional Formula field, which evaluates to either TRUE or FALSE, as shown below:

You will notice that the expression is valid and a variable has been auto-populated in the Variable Mappings section.

2) Select the variable and click on Edit Mappings button.

3) Select the required channel in the System Definition File tree to map to the newly created variable:


Additional Information

The conditional formula must evaluate to either TRUE or FALSE, such as RPM<5000, and ensure that you use the correct operators/functions while writing the formula.

Refer Expression Syntax topic in NI VeriStand Help to get more information about the format of supported syntax in the field.