winddcutil_rs

A Rust implementation of the ddcutil Linux program for Windows. Uses the VESA Monitor Control Command Set (MCCS) over the Display Data Channel Command Interface Standard (DDC-CI) to query and change monitor settings, such as brightness, color levels, input switching and power modes.

Features

• Detect connected monitors
• Query monitor capabilities
• Get VCP feature values
• Set VCP feature values

Installation

From Source

git clone https://github.com/cyb0rg56/winddcutil_rs.git
cd winddcutil_rs
cargo build --release

The executable will be located at target/release/winddcutil_rs.exe.

Usage

winddcutil_rs [COMMAND]

Commands

• detect: Lists all connected monitors with DDC/CI support
• capabilities <display>: Shows the capabilities of the specified monitor
• getvcp <display> <feature_code>: Gets the current value of a VCP feature
• setvcp <display> <feature_code> <new_value>: Sets a VCP feature to a specific value

Examples

# List all monitors
winddcutil_rs detect

# Get monitor capabilities
winddcutil_rs capabilities 1

# Get brightness (feature code 0x10)
winddcutil_rs getvcp 1 0x10

# Set brightness to 75
winddcutil_rs setvcp 1 0x10 75

# Toggle input source between HDMI1 (0x11) and HDMI2 (0x12)
winddcutil_rs setvcp 1 0x60 0x11

Common VCP Feature Codes

• 0x10: Brightness
• 0x12: Contrast
• 0x60: Input Source
• 0xD6: Power Mode

Troubleshooting

No Monitors Found

If you receive a "No monitors with DDC/CI support found" error:

1. Ensure your monitor supports DDC/CI
2. Enable DDC/CI in your monitor's OSD menu
3. Try using a different connection type (HDMI, DisplayPort, etc.)
4. Some monitors require specific drivers to be installed

Invalid Feature Code

If you receive an "Invalid feature code" error:

1. Ensure the feature code is valid (between 0x00 and 0xFF)
2. Check if your monitor supports the specific feature code
3. Use capabilities command to check supported features