Olimex Support Forum

Microcontrollers => ESP32 => Topic started by: stephanino on June 13, 2023, 06:02:28 PM

Title: ESP32-POE multiple BME280
Post by: stephanino on June 13, 2023, 06:02:28 PM
Dear all,
we are using the ESP32-POE to control a BME280 sensor (standard cable 15cm long) through the UEXT connector.
We would like to add another BME280 sensor with a longer cable: do you have any experience about the maximum acceptable cable length between the board and the sensor, please? In any case we are talking about 3-4m for our application.

For the connection this interface (https://www.olimex.com/Products/Modules/Interface/UEXTx5/open-source-hardware) would be enough (with address changing on second sensor)?

Thanks a lot in advance
Title: Re: ESP32-POE multiple BME280
Post by: LubOlimex on June 14, 2023, 09:08:17 AM
In practice I2C is used up to 2 meter of distance between devices. It is short-distance interface. But theory and reality are different things so best idea is to just test empirically.