Open-source sauna infrastructure
Prepare a sauna logger
SLOG is open source software for logging saunas. Install the firmware, verify the logger, and assign its eight temperature probes. Everything stays in this browser.
Stage 1 of 3
Stage 1 · Install firmware
Install SLOG firmware
Connect the XIAO ESP32-C3 normally and choose it in the browser. SLOG enters download mode automatically, then identifies the board before anything can be written.
- Connect USB normally. No button sequence is normally required, including on a new board.
- Free the serial port. Close other SLOG tabs, PlatformIO, and serial monitors.
- Choose the logger. SLOG switches it into ROM download mode and checks the target.
Manual connection recovery
Automatic download mode did not work. Use this physical fallback only for the same XIAO ESP32-C3 you intended to install.
- Disconnect USB and any other power from the board.
- Hold BOOT, reconnect USB, then release BOOT after the board appears.
- Choose the logger again. After flashing, press RESET or power-cycle it if the running logger does not appear.
If other power must remain connected, hold BOOT and press RESET once instead of reconnecting USB.
- Release
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- Target
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- Manifest
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- Image integrity
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- Validate manifest and image hashes
- Enter ROM download mode and identify the ESP32-C3
- Write firmware
- Verify the written image
SLOG accepts only its versioned release manifest and SHA-256-verified image set. There is no file picker or erase option.
Probe setup · Connect
Connect the running logger
Reset into the installed firmware, then choose the serial port that reappears.
- Logger
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- Firmware
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- Configuration
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- Sending eight positions
- Writing CRC-protected map
- Reading map back
- Restarting logger
- Verifying active generation
- Checking all eight probes
Only the device you select is shared with this page. Nothing is uploaded.
Fixed geometry
Probe order
0 of 8 identified
| Probe | Relative position | Status | Temperature | ROM address |
|---|
Technical details
Device and probe details for troubleshooting. The read-only USB transcript is in Diagnostics at the bottom of the page.
- Protocol
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- Source commit
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- OTA slot
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- Generation
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- Configuration CRC
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- USB device
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SLOG records
Stored sauna records
Download CRC-checked raw files from the logger. Save and verify is safest; if the browser cannot verify a saved file, an explicit removal override is available.
Logger
Storage status
Not connected
- Recording
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- Storage
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- 12-hour reserve
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- Retention
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SLOG checks the firmware before reading records. Downloads pause while a recording is active. Nothing is uploaded.
Files on logger
Sauna runs
No file list loaded
Connect a logger to inspect its records.
SLOG analysis
Analyze sauna sessions
Open one or more .slog files to view charts and export
session data. Time while the logger was powered off stays unknown.
Raw files
Open session files
Files are read locally and never uploaded.
- Segments
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- Observed duration
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- Start
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- Integrity
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Temperature timeline
Power-off gaps have unknown duration and are not included in the time axis.
Heating and cooling rate
Selected probe · centered 60-second trend · matched time axis.
| Probe | Height | Samples valid / missing | Peak | Mean | Time at peak | First reached 40 °C | Time ≥ 80 °C | Fastest heating |
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