<img src="images/main.JPG" alt="Starkpad" width="600"/> <h1 align="center">Starkpad</h1> A Linux-Powered Touchscreen Macro Deck & Virtual Input Device <a href="#-features">Features</a> • <a href="#-architecture">Architecture</a> • <a href="#-getting-started">Getting Started</a> • <a href="#-user-manual">User Manual</a> • <a href="#-license">License</a> <img src="https://img.shields.io/badge/Platform-Linux%20%7C%20Embedded-blue?style=flat-square" alt="Platform"/> <img src="https://img.shields.io/badge/License-MIT-green?style=flat-square" alt="License"/> <img src="https://img.shields.io/badge/Protocol-SHIDP%20v1.1-orange?style=flat-square" alt="Protocol"/> <img src="https://img.shields.io/badge/UI-LVGL-lightgrey?style=flat-square" alt="UI Framework"/> <a href="https://youtu.be/fDFRH98BEmM"> <img src="https://img.shields.io/badge/Watch–on–YouTube-red?style=flat-square" alt="Watch on YouTube"/> </a>

📖 Overview

Starkpad is a physical, open-source hardware interface that transforms a Linux-based touchscreen into a fully customizable virtual keyboard, precision touchpad, and programmable macro deck.

Built on the Arduino UNO Q running Yocto Linux, Starkpad renders its interface using the LVGL graphics library. It translates user input into a custom serial protocol (SHIDP) which is sent to a Seeed XIAO RP2040 dongle that emulates a standard USB HID device on the target computer.

💡 No drivers required — works with any PC, Mac, or Linux machine out of the box.

✨ Features

🏗️ Architecture

┌─────────────────┐      ┌─────────────────┐      ┌─────────────────┐      ┌──────────┐
│  Starkpad App   │      │   MCU Bridge    │      │  USB Receiver   │      │ Your PC  │
│  (Linux/LVGL)   │─────▶│  (ATmega4809)   │─────▶│ (Seeed RP2040)  │─────▶│          │
└─────────────────┘      └─────────────────┘      └─────────────────┘      └──────────┘
     /dev/ttyHS1              Passthrough            USB HID Output         Keyboard
      115200 baud             (transparent)           (TinyUSB)             Mouse

🚀 Getting Started

Prerequisites

Hardware: Arduino UNO Q, Seeed XIAO RP2040, Waveshare 12.3" Display
Software: Git, CMake, GCC, Python 3, Arduino IDE
Full parts list: BOM.md

Quick Start

# 1. Clone the repository
git clone https://github.com/BlommeJan/starkpad.git
cd starkpad

# 2. Follow the installation guide
# → installation-manual.md

📘 Full Installation Manual

Access the Web UI

Once running, open in any browser:

http://starkpad-uno-q.local/

📁 Repository Structure

starkpad/
├── Starkpad/
│   ├── lv_port_linux/          # Main LVGL application
│   │   ├── src/starkpad/       # Custom C modules
│   │   └── ui-config/          # JSON config files
│   ├── web-server/             # Python Flask backend
│   ├── shidp_receiver/         # RP2040 firmware
│   ├── uno-q-echo/             # MCU bridge firmware
│   └── scripts/                # Install scripts
│
├── images/                     # Schematics
├── docs/                       # Academic docs
├── starkpad-case-003.stl       # 3D printable case
├── BOM.md                      # Bill of Materials
├── installation-manual.md      # Setup guide
└── README.md                   # This file

📚 Documentation

🔌 The SHIDP Protocol

Serial Human Interface Device Protocol — a lightweight 8-byte frame protocol.

[SYNC] [TYPE] [ACTION] [P1] [P2] [P3] [P4] [CHECKSUM]
 0xAA   0x01   0x00    ...  ...  ...  ...   XOR(0-6)

📖 User Manual

⚡ Powering On

Connect Starkpad to power via USB-C
Plug the RP2040 receiver dongle into your target PC
Wait ~15-30 seconds for boot
Device is ready when the UI appears

⚠️ Important: Run sudo systemctl stop arduino-router on the UNO Q after each boot.

🖥️ The User Interface

┌───────────────────────────────────────────────┐
│  [Keyboard]   [Touchpad]   [Grid]    [Status] │  ← Top Bar
├───────────────────────────────────────────────┤
│                                               │
│              MAIN CONTENT AREA                │  ← Changes per mode
│                                               │
└───────────────────────────────────────────────┘

Tap any tab to switch modes.

⌨️ Keyboard Mode

A full virtual keyboard that sends keystrokes to your computer.

How to use:

Single key: Tap to send
Combo (e.g., Ctrl+C): Hold modifier → tap key → release

Layouts available: en-US, colemak, nl-BE

🖱️ Touchpad Mode

Turns the screen into a precision trackpad.

┌─────────────────────────────────┐
│                                 │
│        TOUCH SURFACE            │  ← Drag to move cursor
│                                 │
├────────────────┬────────────────┤
│  LEFT CLICK    │  RIGHT CLICK   │
└────────────────┴────────────────┘

🎛️ Macro Grid Mode

A grid of 60 programmable buttons per application.

How to use:

Select a Category (e.g., Design)
Select an App (e.g., Figma)
Tap any button to execute its shortcut

Action types:

🌐 Web Configuration

Access

http://starkpad-uno-q.local/

What you can do

Editing a button

Click any button in the grid
Modify: Name, Icon, Actions
Click Save
Click Apply Now to reload config

📄 Configuration File Reference

Location: Starkpad/lv_port_linux/ui-config/config.json

Structure Overview

{
  "settings": {
    "theme": { "bg": {...}, "text_color": "#303450", ... },
    "keyboard": { "language": "en-US", ... }
  },
  "categories": [
    {
      "id": "design",
      "label": "Design",
      "icon": "palette",
      "apps": [...]
    }
  ]
}

Key Object

{
  "name": "Copy",
  "icon": "copy",
  "shortcut": {
    "t": "key",
    "k": "C",
    "m": ["CTRL"]
  }
}

Common Keycodes

Media Keycodes

Examples

Save All (Ctrl+Shift+S):

{ "name": "SaveAll", "icon": "floppy-disk", "shortcut": { "t": "key", "k": "S", "m": ["CTRL", "SHIFT"] } }

Empty slot:

null

Media key:

{ "name": "Play", "icon": "play", "shortcut": { "t": "media", "k": "PLAY_PAUSE" } }

🔧 Troubleshooting

Input not working

Starkpad

Install / Use

README