NetHID

Wi-Fi controlled virtual USB keyboard and mouse

This firmware turns the Pico W microcontroller board into a virtual keyboard and mouse, controllable over wireless network.

As a hardware solution, it appears as a normal USB input device and requires no extra software on the target system.

Features

• USB HID support with keyboard, mouse, and media keys (consumer control)
• Web interface with virtual keyboard, mouse and touch support
• HTTP API for automation
• UDP for low(ish) latency clients
• MQTT for home automation integration

Possible use cases

• Remote media controls (volume, playback)
• Use your laptop or mobile phone as a wireless keyboard
• Automation, e.g. scheduled sleep / wakeup from homeassistant

WiFi Setup

On first boot (or when no WiFi is configured), the device starts in AP mode:

1. Connect to the NetHID-XXXXXX WiFi network (password: nethid123)
2. Open http://192.168.4.1 in your browser
3. Select your WiFi network and enter the password
4. Device reboots and connects to your network

To return to AP mode later, hold the BOOTSEL button for 5+ seconds until the LED blinks rapidly, then release.

Usage

Once connected to your network, access the web interface at the device's IP address or hostname.

The web UI provides:

• Virtual keyboard (TKL layout for desktop, compact layout for mobile)
• Mouse control via trackpad area
• Media keys (play/pause, volume, etc.)

For programmatic control, see the API specification.

MQTT

Configure via Settings in the web UI. The device subscribes to {topic}/#.

Topics:

• {topic}/key - Keyboard: {"key": "a"} or {"key": "ENTER", "action": "press"}
• {topic}/mouse/move - Move: {"x": 10, "y": -5}
• {topic}/mouse/button - Click: {"button": "left", "down": true}
• {topic}/scroll - Scroll: {"x": 0, "y": -3}
• {topic}/release - Release all keys

Key names: a-z, 0-9, ENTER, ESCAPE, TAB, SPACE, BACKSPACE, DELETE, UP, DOWN, LEFT, RIGHT, F1-F12, CTRL, SHIFT, ALT, GUI, VOLUME_UP, VOLUME_DOWN, MUTE, PLAY_PAUSE, etc.

Omit action field for tap (press + release). Use "action": "press" for press, "action": "release" for release.

Building

./build.sh

To build with docker:

docker build -t nethiddev:latest .
USE_DOCKER=1 ./build.sh

After a successful build, the resulting binary is available at build/nethid.uf2.

Flashing

Hold the BOOTSEL button while connecting the Pico W via USB. It will appear as a USB drive. Copy build/nethid.uf2 to the drive.

License

MIT