Sonoff Th10 with additional display

[Xfiles]

Hello, I have question about sonoff th10 and ds18b20 thermometer. I don't have any electronic experience so my question can be quite stupid... I connected ds18b20 to sonoff th10 with espmega and it works correctly. In addition I would like to add display that will show temperature. I have display powered by separate 12v power supply. This display is dedicated to ds18b20 and works correctly after connection. My idea was to have ds18b20 powered by sonoff, display powered by separate power supply and data cable shared by sonoff display. This idea does not work - sonoff after connection is down and display also does not work. Is there possibility to do so type of connection?

[grovkillen]

You need common ground for the ESP and the devices.

[Xfiles]

So I need only possibility to share data from one sensor between display and sonoff. Separately it works. I suspect that maybe voltage after sharing is not proper.

[TD-er]

Who is then the master on the bus?
If I understand correctly, you want to share the sensor among a Sonoff and a separate display?

[Xfiles]

So my idea is in a attachment. Yes I would like to share sensor (Sonoff is the master).