ESP32 as Converter between modbus and SDI

Hey

I've some SDI-12 Sensors : https://www.metergroup.com/environment/products/teros-12/
and a gateway that only communicate with RS485 RTU sensors

I'm planning to use an ESP-32 to collect the readings from the sensors using this library : GitHub - EnviroDIY/Arduino-SDI-12: An Arduino library for SDI-12 communication with a wide variety of environmental sensors. This library provides a general software solution, without requiring any additional hardware.

and then somehow i want to communicate between the ESP and the gateway with modbus to be able to forward the readings to the gateway

I have an idea about using MAX485 to communicate between the MCU and the gateway but i don't know what the steps i need to do it

note : also i may use arduino pro mini instead of ESP-32 to minimize the enclosure and make it productize it in a way as it will be in a real world project

Thanks

Bad idea, MAX485 is for 5V devices, ESP32 runs on 3.3V.

Many versions of the ESP32 are smaller than an Arduino Pro Mini so you might have to provide a link to the ESP32 board you're planning to use.

That's a mix of definitions. You probably meant Modbus RTU sensors. Modbus RTU runs over RS485 as the physical layer so many marketing departments lack the basic knowledge in these details and produce such mis-namings.

What exactly is your problem?