Monitoring or Debugging Measurements

Use InstrumentStudio to monitor and debug measurements with measurement plug-ins that run in a TestStand sequence.

Overview

You can use InstrumentStudio to monitor a measurement while the measurement runs in a TestStand sequence.

The measurement runs as a measurement plug-in service. TestStand controls the execution of the measurement, and InstrumentStudio displays the measurement UI and results.

InstrumentStudio can monitor a running measurement, but only the calling application controls measurement execution.

You can also use InstrumentStudio to run a measurement interactively outside of TestStand.

For general debug behavior, see Debug Measurements from External Applications.

Enable Monitoring

Before InstrumentStudio can monitor a measurement that runs in the TestStand Sequence Editor, you must enable monitoring.

To enable monitoring:

  1. Open your sequence in the TestStand Sequence Editor.
  2. Locate the Variables pane.
  3. Go to FileGlobals » Measurement Plug‑In » EnableMonitoring.
  4. Set EnableMonitoring to True.

Monitoring enables InstrumentStudio to monitor the measurement service while the sequence runs.

Note Enabling monitoring can impact measurement performance.

Monitor a Running Measurement

To monitor a measurement from InstrumentStudio:

  1. Run the sequence in TestStand.
  2. Open the measurement in InstrumentStudio.

InstrumentStudio displays:

  • Current parameter values
  • Measurement results when available
  • Measurement UI updates

Measurement values update only when the measurement service returns results to TestStand.

The measurement UI indicates where active measurement data originates.

Debug Measurements

You can use TestStand and InstrumentStudio together to debug a measurement.

Use the following techniques:

  • Set breakpoints in TestStand to pause sequence execution.
  • Open the measurement in InstrumentStudio to observe measurement behavior.
  • Modify measurement parameters and compare results across runs.
  • Run the measurement interactively in InstrumentStudio and compare results with execution in TestStand.

While a measurement service runs, there are multiple ways to execute the associated measurement logic. The measurement UI toolbar indicates the source of the active measurement data.

Debugging Tools

You can use the buttons next to the Measurement list in TestStand to interact with measurement plug-ins while you debug.

Table 10. Buttons in the Monitoring and Debugging Toolbar
Icon Description

Icon depicting two black arrows pointing at one another in a circular arrangement.
 Reloads parameter values and updates the measurement UI. This action also refreshes the measurement list to display added or removed measurements.

Icon depicting three white lines on a turquoise background.
 Opens the measurement UI in InstrumentStudio. If the measurement is running in TestStand, InstrumentStudio opens the measurement with the current parameter values and pin map associations. If the measurement sequence is open but not running, you can enable monitoring, associate a pin map in InstrumentStudio, or synchronize parameter values by using the copy and paste controls.

Icon depicting a white square with a black outline and a black square partially overlapping. The white square is behind and to the southeast. The black square is in front and to the northwest.
 Copies measurement parameter values.

Icon depicting a white square with black outline and a black square partially overlapping. The white square is behind and to the northwest. The black square is in front and located to the southeast.
 Pastes measurement parameter values.

You can copy and paste parameter values between:

  • TestStand and InstrumentStudio
  • Multiple instances of the same measurement

Troubleshooting

If InstrumentStudio does not display expected measurement data, check the following items.

Table 11. Troubleshooting Monitoring
Possible Cause Action
Monitoring is not enabled Enable monitoring in TestStand.
  1. Go to FileGlobals » Measurement Plug-In » EnableMonitoring.
  2. Set EnableMonitoring to True.
Measurement is not running Run the sequence in TestStand.
Measurement service is not accessible Ensure the measurement service is installed and running.
Data does not update Ensure the measurement returns results during execution.

Performance Considerations

Monitoring a running measurement can affect performance.

  • Additional communication occurs between TestStand and InstrumentStudio.
  • Measurement execution can slow down when monitoring is enabled.
  • Frequent UI updates can increase overhead.

Use monitoring only when you need to inspect or debug behavior.

Displace a Statically Registered Measurement Service

You can temporarily replace a statically registered measurement service with a development instance for debugging.

When you start a measurement service from a development environment:

  • The Measurement Plug-Ins discovery service detects the new instance
  • The statically registered instance stops
  • The development instance handles requests

When the development instance stops:

  • The Measurement Plug-Ins discovery service restarts the statically registered instance as needed

Use unique service classes in production environments to avoid unintended conflicts.