C/C++ Model Parameter Values Do Not Update on VeriStand Screen

Updated Nov 15, 2022

Reported In

Software

  • VeriStand
  • VeriStand Model Framework

Operating System

  • Windows
  • LabVIEW Real-Time (NI Linux Real-Time)

Issue Details

  • Modifying parameter values as part of my C model code does not update on the VeriStand UI/Screen.
  • I can manually change parameter values on the VeriStand screen

Solution

Please note the following behaviours of parameters on a VeriStand screen:
  • Parameters displayed on a VeriStand screen only update when the user changes the value from VeriStand (whether that is manually or through automation).
  • Changes to parameter values from within the model are not read back out into Veristand until the screen controls are modified as above.
If you witness this behaviour:
  1. Verify your model is in the Running state using the Model Status channel. The value will be 0. Refer to the VeriStand help for details on other values.
  2. You can attempt a reset of your model by changing the Model Command channel to 2. The values are documented here.
  3. Monitor some signals within your model to determine the model is running as expected.
If the model is not running, recovering after a reset and/or not updating signals, debug your model code.
Refer to Common Issues with Models in VeriStand and if you have LabWindows/CVI, refer to the debug section here.

If the model is running as expected and signal values are updating correctly, use the following to view parameter values updating during model runtime.
  • Monitor a signal that already uses the parameter value.
  • Create a new signal in the model and map the desired parameter to this signal within the model.
. Signals will show the values as the model runs and give you the up to date value on a VeriStand screen.