All the files you can download from this page have been written or created by myself and you are free to use them. You can use them in any type of project in part or complete if not mentioned otherwise. Use the information on your own risk there is no guarantee it works and the likelihood that it still has bugs or errors is about 100%. Though the code works in my projects and the circuits and PCBs I have designed are in use and work for me. YMMV
Here is the source code of a collection of my projects. Currently I have just included a ZIP file for each project folder and there is not much documentation for the time being and is work in progress.