The functional equivalent to the original firmware of "Digital Thermostat Module Model XH-W1209".
The F.A.Q. page is available at https://github.com/mister-grumbler/w1209-firmware/wiki/FAQ
Look at the list of issues to have an idea of what needs to be done for the initial release. https://github.com/mister-grumbler/w1209-firmware/issues