From what i've understood, the red is +, black - and yellow is dataline.

By using the Adapter you get only a change in color for dataline, this is green with the delivered cable from the picture.

I get my Adapter board in a couple of days, i'll let you know how i did it when mine is running.

How does the Rain Sensor behave? I have connected it, can read firmware and uptime of the sensor as the examples provide.

But when i use this method getRainfall() with or without any argument i get 0.00 back from the sensor.

I checked the getRawData() function and this does show the increased counts i made by testing it.

Does it only return a new value after an hour?

please reach out if you have a solution.