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NetworkTables NT4

Use this guide if you are integrating HeliOS with an NT4 server (commonly the roboRIO).

Goal​

You are done when:

  • the device publishes under the expected prefix
  • the Explorer can list topics

Before You Start​

  • Your NT4 server must be reachable from the device.
  • Most teams use the roboRIO as the NT4 server.
  • If you use team addressing, the roboRIO is usually 10.TE.AM.2.

Example for team 6390:

  • roboRIO host: 10.63.90.2
  • NT4 port: 5810

Configure (UI)​

  1. Open Settings > Networking.
  2. Scroll to NetworkTables (NT4).
  3. Set:
    • Enable NT4 publishing
    • Enable NT4 subscriptions (required for Explorer)
    • Team number (optional) or server host override
    • Port (default 5810)

Derived values:

  • Host from team: 10.TE.AM.2
  • Publish prefix from hostname: /<hostname> (fallback /helios)

What each toggle actually changes:

  • Publishing: HeliOS can write topics.
  • Subscriptions: HeliOS can read topics, and the Explorer UI can query topics.

Explorer​

  1. Click Open Explorer.
  2. Search topics.
  3. Click a topic to read its value.

If Explorer is disabled:

  • enable subscriptions
  • set team number or server host override

Verify (Quick Checks)​

  1. In Explorer, confirm you can see a topic tree (even if it is mostly empty).
  2. Confirm you see your publish prefix and topics under it.
  3. If you have a pipeline that publishes outputs, confirm those topics appear while the stream is running.

Common Problems (And Fixes)​

  • Nothing shows in Explorer:
    • Enable subscriptions.
    • Confirm server host is correct.
    • Confirm the device is on the same robot network as the server.
  • Explorer works but your topics are missing:
    • Confirm the pipeline is running on a Live stream.
    • Confirm you are looking under the correct prefix.
  • Flaky NT4:
    • Avoid multiple NT servers on the same network unless you know which one you intend to use.