Build a Configurable USB HID Launcher with LED Status Using the Waveshare RP2040 Tiny USB-C

Have you ever wanted a USB device that does more than just blink? What if your microcontroller could act like a keyboard, launch programs on your PC, and display status with built-in RGB lighting—all from a tiny board the size of a thumb drive?

In this article, we’ll walk through a fun and practical project using the Waveshare RP2040 Tiny USB-C development board to build a configurable USB HID launcher with LED feedback. This device can automatically launch commands (like URLs in kiosk mode), supports randomized intervals and run-once behavior, and uses its built-in RGB LED to visually indicate its status.

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🛠 What You’ll Need

• Waveshare RP2040 Tiny USB-C board
  A compact RP2040 board with built-in RGB LED and USB-C connector. Lightweight and ideal for HID projects. Available on Amazon:
  • Single unit: great for prototyping
  • 6-pack: cost-effective option at around $17
    (Useful if you want several devices for demos or different use cases.)
    https://www.amazon.com/Microcontroller-Development-Equipped-Processor-unsoldered/dp/B0DXL12W59
    [No Affiliate or Sponsor]

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🚀 What This Project Does

This microcontroller becomes a USB keyboard device. When plugged into a Windows PC it can:

• Press Win + R to open the Run dialog
• Type a configurable command (like launching a browser in kiosk mode)
• Press Enter to execute
• Wait a configurable amount of time between runs
• Show LED animations to indicate:
  • Waiting period
  • Execution
  • Idle state

All behavior is set via a simple config.txt, editable on the board’s CIRCUITPY drive.

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⚙️ Key Features

✅ Configurable Launch Behavior

Your config.txt controls:

• COMMAND – what gets typed and executed
• RUN_DELAY – delay before the first run
• MIN_DELAY / MAX_DELAY – random interval range between runs
• RUN_ONCE – whether to do it just one time or loop indefinitely

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💡 LED Status Indicator

The integrated RGB LED is not just for show. You get:

• Off – no activity
• Solid – fixed color
• Blink – on/off in a chosen color
• Breath – smooth fade in/out
• Rainbow – continuous color cycling
• Rainbow Blink – blink while cycling colors

You can also control:

• LED_COLOR – your base color (e.g., RED, BLUE, CYAN)
• LED_SPEED – how fast animations run
• LED_BRIGHTNESS – brightness level

All of this is controlled through the same config.txt file, which the board re-reads every few seconds so you can tweak behavior without reflashing.

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🧠 How It Works

At startup:

1. RP2040 enumerates as a HID keyboard
2. It reads the config file
3. The LED starts animating based on settings
4. It waits for the PC to recognize the keyboard
5. After an initial delay (if configured), it sends the hotkey combo (Win + R)
6. Types your command
7. Presses Enter
8. Waits a randomized interval (or just once if configured)
9. Repeats

All the while, the LED visually communicates what’s happening.

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📁 What Goes on the CIRCUITPY Drive

CIRCUITPY/
│
├── code.py          # Main program
├── config.txt       # User settings
└── lib/             # Required libraries
    ├── neopixel.mpy
    ├── adafruit_led_animation/
    └── adafruit_hid/

config.txt is structured like this:

COMMAND=msedge --kiosk https://example.com --edge-kiosk-type=fullscreen

RUN_DELAY=10       # Initial delay
MIN_DELAY=30       # After first run
MAX_DELAY=120
RUN_ONCE=false

LED_MODE=Rainbow Blink
LED_COLOR=GREEN
LED_SPEED=150
LED_BRIGHTNESS=255

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💻 Why It’s Useful

• Kiosk automation – automatically launch and cycle through URLs
• Testing workflows – automate app launch or command execution
• Indicator device – quick visual cues for task state
• HID emulation projects – explore creative automation

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🧫 Extending the Project

Here are some ideas you might consider:

• Add a small OLED to show status text
• Build a web interface to edit config via Wi-Fi
• Add buttons to cycle commands manually
• Store multiple commands and rotate through them
• Add sound feedback

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🧾 Final Thoughts

This project shows how powerful a tiny board can be when paired with thoughtful software design. Instead of just blinking, your Waveshare RP2040 Tiny USB-C board becomes a fully programmable automation tool with real-time feedback from its RGB LED.

Want to see more projects like this? Check out ConsultingJoe.com for tutorials, hacks, and real-world automation tips.