CYD PC Dashboard

A 2.8” panel (a board that costs about US$15) that sits next to the monitor and shows, at a glance, what would otherwise mean switching windows. The captures above were read straight from the display’s framebuffer.

What it shows

• Nine tabs: clock, PC (CPU, RAM, temperature, disks and network), processes, network, quotes (currencies, crypto, stocks, ETFs and indexes, with a 24h chart), YouTube, services (whether chosen hosts and sites are up, with latency), media and shortcuts.
• Controls the PC: the Media tab shows what’s playing (Spotify, browsers, players) with previous, play-pause, next and volume buttons. The Shortcuts tab has up to 8 buttons that lock the PC, turn the screen off, open apps or run scripts.
• Notifications from the PC: a command or a curl pops a card on the panel, handy for knowing when a build, a test run or a download finishes.
• Alerts: CPU, RAM and disk thresholds color the gauges and make the PC tab blink from any other tab.
• Uses what the board has: the RGB LED blinks on alerts and notifications, and the light sensor drives the brightness from the room light. At night the screen dims or turns off.

Firmware

• Web interface on the panel itself: a live screenshot you can click to “tap”, every setting editable on the spot, and firmware updates over WiFi (OTA) with automatic rollback.
• Zero-code setup: the web installer flashes the firmware from the browser and sets up WiFi right away. There is also a WiFi portal and automatic discovery of the agent on the network.
• Flicker-free: each dynamic value is drawn into an off-screen sprite and pushed to the display in a single transaction.
• Six color themes (Dracula, Nord, Gruvbox, Catppuccin and more), 100% vector icons and a UI in English and Portuguese.

Problems that took real work

• Corrupted SPI reads: the display and the touch controller shared the same ESP32 SPI peripheral. Writes worked, but display reads came back as zeros. The fix was moving them to separate peripherals.
• Shifted bits on readback: reading the framebuffer at the write clock shifted every byte by one bit. Reads now run at 6 MHz, while writes stay at 55 MHz.

Agent and distribution

• Python agent (psutil and the standard library only): each metric is collected by its own thread and served from cache. The ESP32 only speaks plain HTTP on the LAN, with no API keys or TLS on the microcontroller.
• The agent runs as a Windows executable with no Python required, starts automatically on Windows, Linux and macOS, and supports an optional authentication token.
• 94 tests with pytest running in CI on Windows, Linux and macOS.
• Automated releases: GitHub Actions builds on every tag, produces a single merged binary and publishes the release and the installer.