The code is open source so you have access to it. You need the Windows software (see download below) that comes with the clock to change the code.
The software download provides you with a document that contains more information on the code and the hardware of the device. We are currently translating this document. People who have experience with using code should be able to work with the code and diagrams provided even though there is no translation available yet.
You can have a look at the document by downloading the software (pdf is included) or by checking out the pdf document that is available on the same site. They are identical.
Download “Basic-Editor” (freeware, open source, Windows, English is included):