I have long wanted to use my Calcomp 18x12 DrawingBoard III digitizer on my linux desktop, but struggled to write my own driver using an obsolete driver as a template.

Claude has enabled me to implement a driver and tools over the course of a couple days to make that possible. The longest part was collecting measurements from the board itself, and then testing all the driver settings.

The intent initially was to create a device that would show up under the tablets tab in KDE settings, this proved to cause problems with this type of digitizer. It does not have a pressure sensitive pen, and also has a puck that could be used. When testing in Gimp with both, the pen and the puck, I found I could not get both tools to work using the most obvious buttons.

Since most of the features of the tablet KDE settings tab did not apply to this digitizer, it was decided to create the driver as an absolute position mouse instead. This meant that the logical button selection would work.

In addition, it was discovered that my tablet had areas where the tools did not work. A python user space tool was written to find dead-zones and set the screen input area accordingly. Further, it was desired to have regions of the board with printed macro buttons that could be clicked to execute some action. These tool pallets are setup using a *.toml markup file that defines the different buttons, their position on the tablet, and information such as a label, icon if desired, and an action to perform. The tool pallets can be placed in other areas of the digitizer that were isolated buy defects so as to maximize area usage.

A tool was devised to write the template to a PDF file to print and use on the surface of the tablet.

I was pleased with how quickly I was able to achieve this, and I've made the driver and tools available at:

Calcomp DrawingBoard III Linux Driver