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Downloading Logs

Log data is downloaded from the OnSpeed controller via WiFi.

Via WiFi Web Interface

  1. Connect to OnSpeed WiFi (OnSpeed / angleofattack)
  2. Navigate to http://192.168.0.1/logs
  3. The page lists each log with start time, duration, max IAS, max pressure altitude, and size
  4. Click a filename to download it

The metadata columns come from a small .meta sidecar file written next to each log_NNN.csv when the log closes. Older logs without a sidecar render with em-dashes for the metadata columns but still download and delete normally.

Logging pauses during download — don't download mid-flight

SD card logging is temporarily paused while a file is being downloaded so the SD writer mutex isn't fighting the download stream. It resumes automatically when the download completes, but every IMU sample that fires during the pause is lost (counted as paused_drops in the dbg-log PERF telemetry — typically ~5–20 samples per small file, more for larger downloads).

On the ground that's harmless. In flight, avoid downloading. Pull logs after the flight when the box is on the ground. The same applies to bulk-delete operations.

The /logs page itself does NOT pause logging — only file downloads do. Reloading /logs to check the active log size is safe at any time. If the SD is briefly too busy to list, the page shows "SD card busy, retrying (attempt N of 4)..." and recovers within a few seconds.

Download Speed

WiFi transfers are not fast — the ESP32's WiFi bandwidth is limited. A large log file (50–100 MB) may take several minutes to download. Stay close to the controller for the best signal.

Managing Logs

Deleting Logs

Via the web interface:

  • Navigate to /logs
  • Click the trash icon next to a single log to delete it, or check several rows and click Delete selected to remove them in one pass. Either action shows a confirmation page before files are removed. The log currently being written is protected from deletion.
  • Deleting a log also removes its .meta sidecar.

Via console:

LIST            # See all files
DELETE log_001.csv  # Delete a specific file

Formatting the SD Card

To erase all data and start fresh:

  • Via web interface: /format
  • Via console: FORMAT

FORMAT deletes everything

This permanently erases all log files and configuration on the SD card.