Screen controller

DDCcontrol

We looked at a small command-line utility called ddcutil for controlling monitors a little while ago. It is an excellent tool for controlling various monitor settings exposed over a screen's I2C bus using the DDC/CI standard. The only problem was that ddcutil could be a little too limited, especially when it came to exploring a screen's more experimental or bespoke features and other parameters exposed over I2C from your monitor. DDCcontrol is a more comprehensive utility with the same goals. It works at a hardware level, rather than through user space, and can access manufacture-specific parameters not accessible with ddcutil. Like ddcutil, however, it does all this over the I2C bus, and this means there's always a risk you could mess with something you can't revert, so it's worth being cautious and to only experiment on hardware you're prepared to lose.

With that out of the way, DDCcontrol runs from the command line and can first conveniently scan your I2C bus for any screens. This is especially helpful because getting the wrong device can destroy more than just your monitor. As with dd, sending potentially destructive commands to other devices on your system will cause problems bigger than the wrong screen brightness, and with the correct device now added to the command, you can safely probe your screen for capabilities. This risk is mitigated in DDCcontrol by using a database of known screens and their features, allowing you to safely access parameters outside of the MCCS specification. They're typically options that might otherwise require a menu deep-dive or the activation of some engineering mode, such as refresh rates and color gamuts. It's still useful for switching inputs, but you might also find you can split the display and change the dark levels of your panel.

Project Website

https://github.com/ddccontrol/ddccontrol

If the command-line options in DDCcontrol are too much, there's an excellent GUI that provides the same options in a much more pleasant graphical window.

Process manager