[werk_ag]

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Maybe extra precautions is add resistor on RX and TX signal. But this is only idea

Even simple! With the Wemos you may only need a simple resistor voltage divider on the RX line of the sensor. The 2.5V TX output level of the sensor will be read as logic 1 by RX on the Wemos.

Ok, my fault, i didn´t seen to datasheet of adum1201 for minimal voltage of logic. But i think, there isn´t problem with voltage level ESP8266 on WEMOS. Here is example with arduino, and there is 5V logic, and in another example with Raspberry is 3V3 logic.

I may be wrong, so double check:

S8 - I/O 3.3V
LP8 - I/O 2.5V