Reading sensor values from serial

[Mahko_Mahko]

Do you have some samples of the uart messages?

Have you tried just seeing what the ESPHome UART debugger shows up once connected? You should just need the Tx on the Arduino connected to an Rx on the ESP I think? Maybe GNDs too.

UART Bus

You could look into this technique to read uart without a custom component. I’ve used it a few times.

[How to] UART read without custom component

The UART Bus component provides a write action but no read actions. Typically the UART read is implemented in a custom component that also does the processing. The UART debug sequence can be exploited to act like a call back function whenever there is received data to process. So basically instead of creating a small custom component a large lambda call can be used in the UART debug yaml. This is shared to hopefully help make implementing UART devices a bit easier for average users. It seems t…

Are the Arduino serial pins 5v or 3.3V?