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Publishing NetworkTables Data

AdvantageScope supports publishing NetworkTables data stored in a log file back to a NetworkTables server such as a simulator or robot. Possible use cases include:

  • Replaying matches in simulation for debugging.
  • Mimicking data from a coprocessor on a real robot.
  • Debugging driver dashboard applications using realistic match data.

This feature requires a log file with a full capture of NetworkTables data, which can be generated using WPILib's built-in data logger. Note that AdvantageKit does not support this feature as it instead enables more complete deterministic replay in simulation.

Getting Started​

To start publishing, a log file containing NetworkTables data must be open. Then, follow these steps:

  • Publish to Robot: Click File > Publish NT Data > Connect to Robot.
  • Publish to Simulator: Click File > Publish NT Data > Connect to Simulator.

The top of the window displays the text "Searching" or "Publishing" to indicate the status of data publishing. AdvantageScope attempts to reconnect automatically using the same settings after a disconnect.

All fields will be published using their stored values at the selected timestamp used by many AdvantageScope tabs. This allows for real-time network playback through the same mechanism as playback within AdvantageScope. See App Navigation for more details. If no timestamp is selected, fields are published using their stored values at the hovered timestamp.

To stop publishing, click File > Publish NT Data > Stop Publishing.

Filtering Fields​

By default, AdvantageScope publishes all NetworkTables fields stored in the log file (except server-published meta topics). Some use cases, like mimicking a coprocessor, require only publishing a limited set of fields or subtables. To adjust the set of allowed field prefixes, open the preferences window by clicking Help > Show Preferences... (Windows/Linux) or AdvantageScope > Settings... (macOS).

The "NT Publish Prefixes" option sets the allowable prefixes for fields published to NetworkTables. If left blank, all fields will be included. Otherwise, a command-separated list of prefixes or fields can be provided. See examples below.

  • "SmartDashboard": Include all fields in the "SmartDashboard" table.
  • "SmartDashboard/Auto Selector": Include only the "SmartDashboard/Auto Selector" table.
  • "limelight/tx,limelight/ty": Include only the "limelight/tx" and "limelight/ty" fields.

Limitations​

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  • Fields are published every 20ms, so NetworkTables data originally published at a higher frequency will skip samples.
  • The timestamps of published samples are not preserved. This would be impossible when scrubbing back and forth in time or playing back at different speeds.