MonitorBuddy — Cross-Platform Monitor Control

Monitorbuddy (mbuddy) is a command-line tool to read and change monitor settings via DDC/CI over the Realtek HID (as used by Gigabyte/AORUS OSD Sidekick and similar monitor software). It is open-source and extensible for other vendors.

Project Overview

• MonitorBuddy CLI (Open Source)
  Cross-platform monitor control for Linux, macOS, and Windows.
  Licensed under Apache 2.0, with portions under MIT (see NOTICE).

• MonitorBuddy Stream Deck Plugin (Paid)
  A polished Elgato Stream Deck plugin powered by the CLI backend.
  Allows one-click brightness, input switching, KVM toggles, and more.
  (coming soon)

Supported / Verified Monitors

• Gigabyte M32U (original target)
• Gigabyte M32Q (source)
• Gigabyte M32QC (source)
• Gigabyte M27Q (source)
• AORUS CO49DQ (verified; same HID protocol)
• Other brands coming soon (experimental)

Any Gigabyte display that exposes a Realtek HID device (usually VID 0x0BDA, PID 0x1100) is likely compatible.

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Installation / Building

Linux (Debian/Ubuntu)

sudo apt install libhidapi-dev libudev-dev
go install github.com/leovanalphen/monitorbuddy@latest

macOS (Homebrew)

brew install hidapi
CGO_CFLAGS="-I$(brew --prefix hidapi)/include" \
CGO_LDFLAGS="-L$(brew --prefix hidapi)/lib" \
go install github.com/leovanalphen/monitorbuddy@latest

Windows (MSYS2 ucrt64 toolchain)

1. Install MSYS2 from https://www.msys2.org/ and set up the ucrt64 environment (install the ucrt64 gcc packages if needed).

2. From PowerShell:

$env:Path = "C:\\msys64\\ucrt64\\bin;$env:Path"
$env:CGO_ENABLED = "1"
$env:CC  = "C:\\msys64\\ucrt64\\bin\\gcc.exe"
$env:CXX = "C:\\msys64\\ucrt64\\bin\\g++.exe"

go build -v -o mbuddy.exe ./cmd/monitorbuddy

If the linker later complains about SetupAPI, add:
setx CGO_LDFLAGS "-lsetupapi"

Makefile (Linux/macOS/Windows with MSYS2)

A Makefile is included for convenience with cross‑platform targets:

# Common
make build     # default (on Windows calls win-ucrt64)
make clean     # clean artifacts and cache

# Windows (MSYS2)
make win-ucrt64       # build with UCRT64 toolchain (recommended)
make win-mingw64      # build with MinGW64 toolchain (alternative)
make win-ucrt64-setupapi  # build with SetupAPI explicitly linked

# Linux
make linux

# macOS
make mac

On Windows you must have MSYS2 installed and use the correct gcc (ucrt64 recommended). On Linux/macOS, ensure hidapi development headers are installed.

Example:

# build and list devices
make build
./mbuddy.exe -list

Usage

Detailed usage is documented in docs/USAGE.md.

Quick examples:

# Default filters (Realtek 0x0BDA:0x1100)
mbuddy -list

# Read current brightness
mbuddy -get brightness -mon 0

# Set brightness to 75
mbuddy -set brightness -val 75 -mon 0

Property Reference

See docs/PROPERTIES.md for a full property reference, including:

• Standard VCP properties (DDC/CI)
• Gigabyte / AORUS vendor extensions

Stream Deck Plugin (Commercial)

A paid Stream Deck plugin built on MonitorBuddy is in the works. 👉 [Plugin page — coming soon]

This plugin uses MonitorBuddy as a backend to control monitors directly from your Stream Deck.

Troubleshooting

• No devices found: try -vid 0 -pid 0 and run -list.
• Windows build errors: use MSYS2 ucrt64 or mingw64 gcc; MSVC cl/link won’t work.
• Nothing changes on monitor: ensure the monitor’s USB upstream is connected.
• Parsing errors on read: some models are sensitive to timing; retries are included, try rerunning.

Contributing

PRs welcome! Especially:

• Confirming additional compatible models
• Filling in enumerations (per-model input maps, languages)
• New vendor-specific codes and descriptions

Acknowledgements

This project was originally inspired by and based on gbmonctl by Kelvie Wong, licensed under MIT.
See NOTICE for detailed attribution and licensing information.