> ## Documentation Index
> Fetch the complete documentation index at: https://docs.altnautica.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Telemetry

> Live sensor stream and the full flight-controller parameter editor.

# Telemetry

The Telemetry page exposes two surfaces: the live sensor stream pushed
by the flight controller, and the full FC parameter table.

<Frame caption="Drone Telemetry page: live sensors above, virtualized params table below.">
  <img src="https://mintcdn.com/altnautica/5zXPDtKnZ8vtFffN/images/dashboard/drone/telemetry-full.png?fit=max&auto=format&n=5zXPDtKnZ8vtFffN&q=85&s=54f54fb0f00a1816cb9e17a4e2c9043e" alt="Telemetry page" width="2880" height="1800" data-path="images/dashboard/drone/telemetry-full.png" />
</Frame>

## Live sensors

Streamed via the dashboard snapshot endpoint. Each entry has a stable
id, a current value, and a state badge. Sensors with no recent value
fall back to a dash placeholder.

## Parameters

The agent caches the FC parameter table on first connect and keeps a
local copy in sync as values are written. The dashboard renders the
table virtualized for the \~800-parameter ArduPilot surface.

### Common operations

<Steps>
  <Step title="Search">
    Type into the search box. Matches name + description. The list
    re-virtualizes on every keystroke.
  </Step>

  <Step title="Edit a value">
    Click the value, type the new number, press Enter. The edit goes to
    a pending bucket so you can stage multiple edits before pushing.
  </Step>

  <Step title="Push to FC">
    Click **Save to RAM**. The agent batches the writes, retries on
    `PARAM_ACK` timeouts, and surfaces per-param failures. ArduPilot
    auto-saves to EEPROM on every `PARAM_SET`, so no separate flash step
    is needed.
  </Step>

  <Step title="Commit to flash">
    Click **Commit to flash** if you want the belt-and-suspenders
    `MAV_CMD_PREFLIGHT_STORAGE` to fire. The agent treats this command
    as fire-and-forget because ArduPilot does not reliably ACK it.
  </Step>
</Steps>

## Profile gating

Telemetry is a drone-only page. On a ground-station profile this URL
renders the "Not available on this profile" panel.

## Backend endpoints

| Method | Path                         | Purpose                                     |
| ------ | ---------------------------- | ------------------------------------------- |
| GET    | `/api/params`                | Full parameter dump (cached)                |
| GET    | `/api/v1/dashboard/snapshot` | `sensors` array on every poll tick          |
| POST   | `/api/params/{name}`         | Single-parameter write (used by the editor) |

## Troubleshooting

<Accordion title="Params table is empty">
  The agent has not finished its initial dump from the FC. Wait for the
  header to flip from "Loading" to "Loaded N params". A stuck load usually
  means the MAVLink serial baud is wrong or the FC has not heartbeated
  yet. Check the Flight Controller card on Home.
</Accordion>

<Accordion title="Save to RAM reports per-param failures">
  ArduPilot rejects writes that are out-of-range or read-only. The error
  column shows the FC's response. Read the parameter's docs in
  [REST API reference](/drone-agent/rest-api) or the FC firmware
  documentation before retrying.
</Accordion>

## Related

* [Home (Flight Controller panel)](/drone-agent/dashboard-home)
* [MAVLink proxy](/drone-agent/mavlink-proxy)
* [REST API reference](/drone-agent/rest-api)