TuringMonitor (Turing Smart Screen Linux)

A high-performance .NET 10 System Monitor for 3.5" Turing Smart Screens on Linux (Turing Smart Screen / Revision A). Features Native AOT for ultra-low memory footprint and a fully customizable JSON theme engine.

🚀 Key Features

• Native AOT: High-performance native binary with ultra-low memory footprint (< 20MB).
• Theme Engine: Fully customizable JSON-based layout system with real transparency support.
• Live Reload: Calibrate your layout in real-time—save the JSON and see changes on the LCD instantly.
• Delta Updates: Intelligent rendering that sends only modified pixels to the hardware for high responsiveness. Overlap-aware redraw ensures dependent elements are refreshed correctly.
• Full Telemetry: Real-time data for CPU, GPU (NVIDIA), RAM, Network, and Weather.
• Auto-Reconnect: Automatic serial port reconnection with exponential backoff and port re-detection. The LCD recovers on its own after USB disconnects/reconnects.
• Robust Error Handling: All failures are logged with appropriate severity (no silent exceptions). The service keeps running even if sensors or the LCD are unavailable.
• Non-Blocking Weather: Weather data is fetched in the background (every 30 min, continuous interval from the last successful fetch) and never stalls the telemetry loop. Includes exponential-backoff retry (5s → 10s → 20s → 40s → 80s, up to 5 retries) so it survives slow network bring-up at boot. The last successful reading is persisted to /var/lib/turing-monitor/weather.json and restored on startup, so the display never shows a stale 0°C after a reboot. Falls back gracefully if the API is unreachable.

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🛠️ Quick Installation

1. Prerequisites

• Nobara Linux / Fedora (Currently developed and tested on Nobara; other distros are not yet tested).
• .NET 10 SDK (required for building).
• Dependencies: libicu, libssl, libusb.
• A 3.5" Turing Smart Screen (Revision A).

2. Install using Script

We provide a simple installation script that builds the project and sets up a systemd daemon:

chmod +x install.sh
./install.sh

The script will:

1. Build the binary using Native AOT.
2. Install the application to /usr/local/bin/TuringMonitor.
3. Configure and start a systemd service (turing-monitor.service).
4. Add your user to the dialout group for serial port access.

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🎨 Theme Guide

Selection

To change the active theme, edit appsettings.json:

{
  "Theme": "MyCustomTheme"
}

Themes are located in Assets/Themes/.

Creating a Custom Theme

1. Create a new folder in Assets/Themes/[ThemeName].
2. Add a background.png (480x320).
3. Create a theme.json file.
4. (Optional) Add an Icons/ folder with weather icons (01d.png, etc).

Global Configuration (theme.json)

Field	Description
Background	Background image file name.
FontPath	Path to a .ttf font file (relative to root).
DebugMode	If true, draws red bounding boxes around elements.
Latitude / Longitude	Geographical coordinates for weather.
WeatherApi	Weather data provider. Default openmeteo (keyless). Optional: openweather or openweathermap (alias) — requires an API key.
WeatherIconsSource	Source for weather icons. Default local (uses Icons/{icon}.png from theme). Optional: online — downloads OWM icons to IconCache/ on first use; uses Icons/ only as fallback if the download fails.
OpenWeatherApiKey	API key for OpenWeather when WeatherApi=openweather. Recommended to put the key in appsettings.json (OpenWeatherApiKey) instead — it has priority over theme.json. See Weather Providers.

Element Types

• Text: Renders formatted strings.
• ProgressBar: Segmented horizontal bar.
• Gauge: 180° segmented arc.
• Icon: Dynamic PNG icons based on weather.

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📊 Data Sources

• CpuName, CpuLoad, CpuTemp, CpuClock, CpuPower
• GpuModel, GpuLoad, GpuTemp, GpuPower, VramString, VramPercent
• RamString, RamPercent
• NetInMbps, NetOutMbps, NetInString, NetOutString
• WeatherTemp, WeatherIcon
• DateTime

Weather Providers

TuringMonitor supports two weather data providers, selectable per theme via WeatherApi in theme.json:

Provider	WeatherApi value	API Key	Endpoint
Open-Meteo (default)	openmeteo	none	api.open-meteo.com/v1/forecast
OpenWeather (optional)	openweather (or alias openweathermap)	required	api.openweathermap.org/data/2.5/weather (Current Weather Data 2.5, free tier ~1000 calls/day)

API Key resolution: when WeatherApi=openweather, the key is resolved as appsettings.json:OpenWeatherApiKey (priority) ?? theme.json:OpenWeatherApiKey. To keep your key out of the theme folder (and out of any shared theme download), place it in appsettings.json or, preferably, appsettings.local.json (gitignored by default — see .gitignore):

{
  "OpenWeatherApiKey": "your-api-key-here"
}

Fallback behavior:

• If the key is missing or invalid (HTTP 401) with openweather configured → logs ERROR, falls back permanently to Open-Meteo for the current session.
• If the OpenWeather call fails transiently (timeout / 5xx / network) → logs WARNING, keeps openweather as the provider, and uses the last cached value. Does not mix providers within a session.
• If WeatherApi is an unknown value → logs ERROR, uses openmeteo.
• Open-Meteo (openmeteo, the default) keeps the existing behavior unchanged.

Refresh scheduling & retry: the cache TTL is 30 minutes continuous from the last successful fetch (not aligned to wall-clock slots like :00/:30 — both APIs return instantaneous conditions, so aligning to fixed slots would only discard valid recently-fetched data). On failure, FetchWithRetryAsync retries up to 5 times with exponential backoff (5s → 10s → 20s → 40s → 80s); if all attempts fail, the next fetch is gated for 80s to avoid hammering the API. The last successful reading (temp, icon, timestamp) is persisted to /var/lib/turing-monitor/weather.json (with a $HOME fallback when not running as a service) and restored on startup if it is less than 6 hours old — so after a reboot the display shows the last known value immediately instead of 0°C while the first fetch is in progress.

Icons: weather icon codes are native OpenWeather codes (01d, 04n, etc.). When WeatherIconsSource=online, icons are downloaded once to Assets/Themes/[Theme]/IconCache/{icon}.png and reused from cache. If a cached icon already exists it is used directly. If the download fails, the icon in Assets/Themes/[Theme]/Icons/{icon}.png is used as fallback; if neither exists, a geometric placeholder is drawn. In local mode (default), only Icons/{icon}.png is used (current behavior).

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⚖️ License

This project is licensed under the MIT License. Created by bendak.